A circuit for controlling at least two power switches that are series connected between a source of electrical power and an electrical load, for energizing the load in response to a signal at a control input. The circuit includes a programmed controller having an input as the control input and a voltage sensor circuit connected to sense the voltage between the power switches and apply a voltage signal to a controller input. It may also have a sensor for sensing the current through the switches and applying a current signal to the controller. The controller inputs the voltage between the switches or the current through the switches to provide a sensed first value. It compares the sensed first value to an expected first value that exists if both switches are turned off. One of the two switches is turned on if the sensed first value is equal to the expected first value. If the first switch was turned on, the voltage at the node between the switches or the current through the switches is sensed to provide a sensed second value. The sensed second value is compared to an expected second value that exists if the first switch is turned on and the second switch is turned off. If the sensed second value is equal to the expected second value, the second switch is turned on. At any of these stages, if a sensed value is unequal to the expected value, turning on of the switches is aborted and both switches are turned off.

1. Field of the Invention
This invention relates generally to the fail safe switching of electrical power to an electric load, such as an electric motor driving a hydraulic pump of a wheel chair lift, through a pair of series connected power switches or contactors and more particularly relates to both the control of the sequential switching of such switches as well as the monitoring of the switch operating conditions in association with the sequential switching process in order to detect switch malfunctions.
2. Description of the Related Art
There are many types of machines that transport people or move mechanical apparatus in the vicinity of people or otherwise require reliable control so they do not malfunction and cause personal injury or property damage. One of the most common electrical loads associated with such machines is an electric motor that is or drives a prime mover to move the mechanical apparatus. Such machines should not only operate when they are signaled or otherwise commanded to operate, but of more critical importance to safety is that they stop operating when they are signaled or otherwise commanded to stop. Although the invention is applicable to a broad variety of machines with electrical loads that have such control and safety requirements, it is illustrated in connection with one such machine, a wheelchair lift having an electric motor driven hydraulic pump as its prime mover.
Many buses and vans are equipped with hydraulic wheelchair lift systems. In wheelchair lift systems, safety is probably the single most important factor. These lifts transport people who have a physical disability and it is particularly desirable to avoid jeopardizing them with apparatus that has the possibility of failing and causing personal injury.
Typically, these lift systems consist of a platform that can be folded and unfolded between a vertically oriented, stowed position in the vehicle and an unstowed, transporting position horizontally extending from the vehicle floor. From its unfolded or unstowed position, the platform can be raised and lowered between the vehicle's floor level and the ground level like an elevator. The lift of FIG. 1 is a typical wheel chair lift system. Most such prior art lift systems use essentially the general principles that are illustrated. The lift allows a person in a wheelchair to roll along the ground and onto the lift platform to be raised into the vehicle. The platform is then raised from ground level up to the vehicle's floor level. After reaching the floor level, the person rolls from the platform into the vehicle. Then the person operates the mechanism to cause the platform to pivot into the vehicle and stow the lift in the vehicle.
To minimize the cost and complexity of a wheelchair lift system, it is advantageous to perform the platform lifting function and the stowing function utilizing a single hydraulic cylinder or two or more cylinders 1 operated hydraulically in parallel, such as illustrated in FIG. 1.
FIG. 2 shows the fundamental mechanical structures of a typical wheel chair lift system that incorporates a hydraulic cylinder 1 to perform both the wheelchair lowering and lift functions and the platform deployment and stow functions. The system includes a first fixed vertical pillar 2 that is securely attached to the vehicle. A lifting platform 3 is attached to a second, vertically movable, vertical pillar 4 at a hinging pivot 5. A brace 9 is attached between the vertical pillar 4 and the platform 3 in such a fashion as to limit the range of motion of platform 3 around hinging point 5 so that it can pivot to no more than a 90° angle to the vertical pillar 4. The vertical pillars 2 and 4 are mechanically coupled to each other with two parallel equal length arms 6 and 7 that are hinged at their attachment points to the vertical pillars 2 and 4. The hydraulic cylinder 1, when operated, raises the platform 3 from ground level up to vehicle floor level. Whenever the platform 3 is raised above floor level, a stop 8 engages a platform protrusion 3a which directs the motion of the platform 3 around its hinging point 5 causing the platform 3 to fold, that is to pivot upwardly about its pivot axis 5 near its innermost edge until it reaches a substantially vertical orientation.
This operation is illustrated in more detail in FIG. 3 but the hydraulic cylinder is not illustrated in order to simplify the drawing and because it can be located in multiple optional positions. As known to those skilled in the art, the hydraulic cylinder or cylinders can be located to either push or pull in order to raise the lift, depending upon which obliquely opposite pivots for the arms 6 and 7 that it is connected to in the parallelogram arrangement that supports the platform. A hydraulic cylinder can also be attached separately from the pivots for the arms 6 and 7 since the purpose of a hydraulic cylinder is to raise and allow lowering of the vertical pillar 4 relative to the vertical pillar 2.
A wheelchair lifting cycle begins, as illustrated in FIG. 3A, with the wheelchair lift system fully deployed so that the platform 3 is resting at ground level. In this position a wheelchair can easily be rolled on to or off of the platform. Pumping fluid into the hydraulic lifting cylinder causes the second vertical pillar 4 and platform 3 to rise with respect to vertical pillar 2 from ground level towards the vehicle floor level as shown in FIG. 3B. The lifting cycle is completed when platform 3 reaches the vehicle's floor level as shown in FIG. 3C. In this position a wheelchair can easily be rolled between the pillars into or out of the vehicle.
Once the lift has served its purpose to raise the user to the vehicle floor level, the lift needs to be stowed. A stow cycle begins with platform 3 at vehicle floor level as illustrated in FIG. 3D. The mechanical structures are so arranged that after the platform reaches floor level, application of more force from the hydraulic cylinder causes the platform to pivot around its pivot point 5 because further vertical movement of the platform is limited by the floor level stop 8. Pumping fluid into the hydraulic cylinder causes the second vertical pillar 4 to rise with respect to vertical pillar 2 in turn forcing platform 3 to fold around pivot 5 as shown in FIG. 3E because the protruding part 3a of the platform 3 engages the stop 8, causing the platform to fold in against the pillars as the pillars 2 and 4 are driven together by the hydraulic cylinder, as shown in FIGS. 3D-3F. The stowing cycle is complete when platform 3 is fully recovered to its vertical stowed position as shown in FIG. 3F.
These operations are reversible. Releasing fluid from hydraulic cylinder when platform 3 is in the fully stowed position, as shown in FIG. 3F, allows the force of gravity to first cause the second vertical pillar 4 to descend with respect to the first vertical pillar 2 allowing platform 3 to unfold around pivot 5. The unstow operation is complete when platform 3 is fully deployed and is parallel to and level with the vehicle's floor as shown in FIG. 3C. From this position a wheelchair can easily be moved from the vehicle onto the platform. Releasing additional fluid from the hydraulic cylinder causes the second vertical pillar 4 and platform 3 to descend with respect to the first vertical pillar 2 from vehicle floor level to ground level. The platform lowering operation is complete when platform 3 reaches ground level as shown in FIG. 3A.
Turning now to the electrical and hydraulic circuitry, FIG. 4 illustrates a basic prior art hydraulic circuit and electrical controlling circuit for a wheelchair lift system described above although some conventional, prior art components and options are not included.
The hydraulic circuit includes a hydraulic lifting cylinder 11, an electric motor driven hydraulic pump 12, a normally closed, electrically energized, hydraulic fluid bypass valve 13 and a hydraulic fluid reservoir tank 14. A battery BAT is connected to a contactor 15 that operates as a power switch to control electrical current through the electric motor of the electric motor driven hydraulic pump 12. The electric motor is not directly switched on and off by a mechanical, hand-held switch because the motor currents are too large and would require an excessively large electrical cable in the user's hand to control the lift. So the separate contactor or power switch 15 is used. When electric power is applied to the hydraulic pump 12, fluid is pumped from the reservoir tank 14 to the lifting cylinder 11. Check valves internal to the hydraulic pump 12 prevent reverse hydraulic fluid flow through the pump. When power is applied to the bypass valve 13 and if the hydraulic lifting cylinder 11 is under pressure from a force applied to it, such as gravity, hydraulic fluid will return from the lifting cylinder 11 through the bypass valve 13 to the reservoir tank 14.
Low current switches 16, 17, 18, 19 and 20 control the power contactor 15. These include four separate hand control switches 17, 18, 19 and 20. Two of these switches, 17 and 18 can apply power to the contactor, closing its high current circuit and thereby applying current to the electrical motor to cause the motor to operate and develop hydraulic pressure for raising the lift. Two other switches 19 and 20 operate the bypass valve 13 causing fluid to drain from the hydraulic cylinder for its lowering movement. Each of the two sets of hand control switches is controlled by a fifth switch 16, and that fifth switch is mounted to the lift as a limit switch to be engaged and change state when the platform reaches the vehicle's floor level. Consequently, when the platform 3 is at ground level or at any intermediate position between the positions of FIGS. 3A and 3C, switch 16 is in the state illustrated in FIG. 5. When the platform is rising and arrives at the position of FIG. 3C, the switch 16 switches to the opposite state and is in that state at every position above that.
There are four distinct functions performed by the wheelchair lift system described above which are:
1. Raising the platform
2. Stowing the platform
3. Deploying the platform
4. Lowering the platform
When the platform 3 is at ground level, switch 16 can supply power to switches 18 and 19. Switch 18 controls raising the platform. If platform 3 is below floor level, switch 16 connects the battery positive terminal to switch 18. Manually closing switch 18 connects the battery positive terminal to power contactor 15 in turn switching battery positive to apply battery voltage to the hydraulic pump 12. Unless switch 18 is opened, the hydraulic pump continues to operate until the platform reaches floor level at which time switch 16 changes state and removes battery power from switch 18 and the power contactor 15. When it does, the circuit to the contactor 15 through switch 18 is opened which interrupts the motor current and automatically stops the ramp at that level. At that point the user gets off the lift platform and then wants to stow the lift.
The user initiates stowing of the lift by pushing the stow button, to close switch 17 which controls stowing the platform. Manually closing switch 17 connects the battery positive terminal to power contactor 15 in turn switching battery positive to the electric motor of the hydraulic pump 12. The hydraulic pump operates raising the platform 3 from the vehicle floor level position to the fully stowed position at which time the switch 17 is manually released by the user. Of course a limit switch can be included to assure that the electric motor ceases operation.
Switch 20 controls deploying the platform. If platform 3 is above floor level, switch 16 connects the battery positive terminal to switch 20. Manually closing switch 20 connects battery positive to the hydraulic bypass valve 13 operating it to cause hydraulic fluid to drain from hydraulic cylinder 11 to reservoir tank 14. The hydraulic cylinder 11 retracts until the platform reaches floor level at which time switch 16 changes state and removes battery power from switch 20 and the hydraulic bypass valve 13.
Switch 19 controls lowering the platform from the vehicle floor level. Switch 16 connects the battery positive terminal to switch 19. Manually closing switch 19 connects battery positive to the hydraulic bypass valve 13 operating the valve 13 causing hydraulic fluid to drain from hydraulic cylinder 11 to the reservoir tank 14. The hydraulic cylinder 11 retracts until platform 3 reaches ground level or switch 19 is released.
Safety is the first consideration in the operation of any wheelchair lift system. The failure of any single component, switch, sensor or control should not affect safe operation. Examining the electrical schematic of the typical wheelchair lift system depicted in FIG. 4 reveals several intrinsically unsafe design problems. First, the electrical contacts of power switch 15 could fail. Unlike low current control switches that can reliably operate for tens of thousands of cycles, high current power switches historically are much less reliable. Typically, in power switches the electrical contacts fail long before the mechanical actuating apparatus because of the relatively high currents they carry and the reactive loads to which they are connected. If the wheelchair platform were occupied during a lift cycle and the contacts in power switch 15 were to weld closed or shorted, the electric motor could not be de-energized and the platform would transition from the lift cycle directly to the stow cycle. In other words, the lift platform 3 with the occupant still on it would just keep moving past the vehicle floor level and begin to pivot to its stowed, vertical orientation.
Some wheelchair lift manufacturers have recognized the safety problem of the welded contacts and have added a second, series-connected power switch to circuits controlling hydraulic motors. Referring to FIG. 5, a first power switch 21 is shown in series with a second power switch 22 and having their respective control windings connected in parallel so both are opened and closed simultaneously. Except for the use of the dual power switches 21 and 22, the circuit of FIG. 5 is the same as the circuit of FIG. 4. The theory is that, if one contactor fails to open, it is probable that the other will open. That does reduce the probability of such a failure. As known to those in the electrical arts, the power switches can be interposed anywhere in the circuit extending from the power source to the electric motor and its return loop. Thus, they can be on the positive or negative side of a DC power circuit.
However, examining the electrical schematic shown in FIG. 5 reveals remaining safety problems. The dual contactor solution does not eliminate the possibility of an eventual failure because the second contactor is also likely to eventually fail. The predominant failure mode in the industry is stuck or welded contacts in these high power switches. If both power switches fail in a shorted mode, the result is the same cause of serious injury. In one scenario, a first switch would fail in a contact shorted mode at a time near the end of its normal life cycle. Lift operation would continue without any apparent problem until the second switch failed. Since both power switches are operated simultaneously, they both see the same number of mechanical cycles and they both see the same electrical loads and therefore both switches experience the same mechanical and electrical wear. After a first switch failure there is a higher probability of a second switch failure. Although using two series switches statistically increases the probable time to circuit failure, it does not prevent ultimate circuit failure and the resulting hazard.
It is therefore an object and feature of the invention to provide a failsafe improvement in the way these switches are controlled and operated to eliminate the possibility of having two switches fail at the same time, potentially causing the lift to fail and pass through to full stow mode causing injury.
Another object and feature of the invention is to provide a control method and circuit that is equally applicable to semiconductor power switches, and other mechanical switches for supplying power to an electrical load.
Yet another object and feature of the invention is to provide a method and circuit for controlling such power switches in other types of apparatus in which dual series connected switches supply electrical power to an electrical load.

Control and operating condition monitoring of dual series switch contactors for electric motor or other electrical load


A vertical-type electric contactor connected to a bump of an electric contactor is provided. The vertical-type electric contactor includes a support beam, vertically bonded with the bump, in which at least two elastic parts are spaced apart from each other; a fixed part disposed at the bottom end of the support beam for fixing the support beam; and a tip part disposed at the bottom end of the fixed part, the tip part and the fixed part being a single body. According to the vertical-type electric contactor, a reaction force generated at a tip part is effectively distributed to test electric devices without damage of the vertical-type electric contactor.

In recent years, capacity of semiconductor devices is advancing to 255 MDRAM and 1 GDRAM. With the advance in capacity of semiconductor devices, package technologies adopt C4 (controlled collapse chip connection) rather than SOC (system on chip). Hence, WaferLevel package technologies are widely used to package semiconductor devices.
Such WaferLevel package technologies require development of vertical-type electric contactor of a probe card for testing ball-shaped pads arranged in a matrix.
As illustrated in FIG. 1(a), conventional vertical-type electric contactor includes a body 2 having a square-column shape and a plurality of protrusive tips 1 formed on the bottom of the body 2. Each of the tips 1 has a pyramid shape or a truncated pyramid shape, and the tips 1 and the body 2 is a single body. The body 2 and the tips 1 are each made of conductive material such as nickel or nickel alloy. As illustrated in FIG. 1(b), a cylindrical body 3 may be provided.
FIG. 2 shows the example where such a conventional vertical-type electric contactor is used. Generally, a vertical-type electric contactor is vertically fixed to a probe card by a predetermined physical force, contacting a test portion of a to-be-tested substance such as a ball-shaped pad 4 of a semiconductor device. Thereafter, an electrical signal is applied to the pad 4 to test whether the semiconductor device is normal.
In the event that the semiconductor device is tested by means of the conventional vertical-type electric contactor, the body 2 or 3 is inelastic or fragile. A sufficient overdrive (OID) value may not be obtained with the shape of the body 2 or 3. Moreover, it is difficult to efficiently distribute a reaction force generated at a probe tip 1 when the probe tip 1 contacts the pad 4 to secure a sufficient OID value that a probe card needs.

Vertical-type electric contactor and manufacture method thereof


A fuel cell hydrogen recovery system comprises a primary hydrogen absorbing tank adapted for storing hydrogen discharged from a fuel cell and a secondary hydrogen absorbing tank adapted for storing part of hydrogen that is supplied to the fuel cell. The primary hydrogen absorbing tank and the secondary hydrogen absorbing tank are provided so that heat can be exchanged therebetween. Part of hydrogen that is supplied to the fuel cell is supplied to the secondary hydrogen absorbing tank, so that the primary hydrogen absorbing tank is heated by hydrogen absorbing heat generated when hydrogen is absorbed therein, whereby hydrogen absorbed in the primary hydrogen absorbing tank can be re-supplied to the fuel cell.

1. Field of the Invention
The present invention relates to a fuel cell hydrogen recovery system which utilizes a hydrogen absorbing alloy adapted for recovering hydrogen (purged hydrogen) which is discharged from a fuel cell.
2. Description of the Related Art
A proton exchange membrane fuel cell (PEFC) has an MEA (membrane-electrode assembly) in which a solid polymer membrane (an electrolyte membrane) is held between an anode and a cathode so that electricity can be generated even at normal temperatures, and therefore, the proton exchange membrane fuel cell can be expected to be used for various applications including an application to a power supply for electric vehicles.
Raised as a method for supplying hydrogen for use as a fuel for the proton exchange membrane fuel cell are a method (of pure hydrogen type) in which hydrogen in the form of pure hydrogen is supplied to a fuel cell from a liquid hydrogen tank which stores therein liquid hydrogen, a high pressure hydrogen tank which stores therein hydrogen under high pressure or a hydrogen absorbing tank which stores therein hydrogen supplied to a hydrogen storage material such as a hydrogen absorbing alloy which absorbs and retains hydrogen in the interior thereof and a method (of reforming type) in which hydrogen rich gas generated from hydrocarbon such as a methanol aqueous solution through a steam reforming process is refined and hydrogen rich gas so refined is then supplied to a fuel cell.
Among automobiles provided with fuel cells to which hydrogen is supplied using the method of pure hydrogen type (hereinafter, referred to as fuel cell vehicles), in a fuel cell vehicle of a highly pressurized hydrogen storage type which has a high pressure hydrogen tank, hydrogen stored in the high pressure hydrogen tank is normally regulated with respect to its pressure in a few steps down to a predetermined pressure before it is supplied to the fuel cell in order to prevent a damage to a fuel cell stack.
In addition, in the fuel cell vehicle constructed as described above, except for a case where the amount of hydrogen stored in the high pressure hydrogen tank is nearly zero, the pressure of hydrogen is reduced from a high pressure condition via a medium pressure condition to a low pressure condition by regulators along a hydrogen supply line which supplies hydrogen from the high pressure hydrogen tank to the fuel cell, and the hydrogen so regulated is further regulated with respect to its pressure down to a lower pressure condition suitable for operation of the fuel cell. A fuel cell system of highly pressurized hydrogen storage type which is adapted for domestic use also has substantially the same construction.
Furthermore, in the proton exchange membrane fuel cell, when a gas containing hydrogen (a fuel gas) is supplied to an anode, whereas an oxidizing agent gas (air) is supplied to a cathode, electrons discharged from the hydrogen gas at the anode to thereby produce protons (ionized hydrogen). Protons produced at the anode pass through the proton exchange membrane (the electrolyte membrane) to reach the cathode together with water, where the protons are oxidized by oxygen in the air to thereby produce water.
Note that since the proton exchange membrane (the electrolyte membrane) always needs to be humidified in order to facilitate the movement of protons through the membrane, the gas containing hydrogen (the fuel gas) and the oxidizing agent gas (air) are humidified before they are supplied to the fuel cell.
While the proton exchange membrane fuel cell is kept at a high temperature by virtue of heat generated through a chemical reaction (thermal reaction) between hydrogen and oxygen in the air when electricity is generated, an electricity generating location of the fuel cell which is closed to an outer peripheral part of the fuel cell is cooled more than a central part thereof. As a result, water in the humidified fuel gas causes a moisture condensation or water produced at the time of generating electricity causes an aggregation along a flow path of hydrogen supplied to the proton exchange membrane fuel cell, and an occlusion of the flow path is caused by water which has so condensed or aggregated to thereby reduce the area of the electricity generating location, leading to a risk that the function of the fuel cell is deteriorated.
In addition, at a cold time such as in winter, there occurs a case where the temperature of the fuel cell lowers below 0° C. while the operation of the fuel cell is stopped. As this occurs, reaction-generated water remaining in the fuel cell gets frozen and then blocks the hydrogen flow path, whereby the fuel cell is not allowed to generate electricity, or such blocking occurs partially along the hydrogen flow path, whereby only portions of the fuel cell is allowed to generate electricity, and the electricity generating portions of the fuel cell are excessively heated relative to the total power output of the fuel cell, leading to a risk of inducing a damage to the electrolyte membrane.
As has been described heretofore, in the event that the hydrogen flow path gets blocked due to water so frozen within the fuel cell, since an unfavorable thing such as a decrease in electricity generating efficiency or power output occurs, there exists, for example, an operating method for feeding an excessive amount of hydrogen which exceeds an amount of hydrogen required for generating electricity to the anode side so as to purge the fuel cell of the excess water which is blocking the flow path together with the excess hydrogen so fed.
After having been used as the means for eliminating the blockage of the hydrogen flow path, hydrogen so discharged from the fuel cell (hereinafter, referred to as purged hydrogen) is desirably recovered for reuse as fuel. To this end, making use of, for example, hydrogen absorbing alloys (hereinafter, referred to as MH) which can store a relatively large amount of hydrogen has been studied as a method for recovering and reusing the purged hydrogen.
There is a technique such as disclosed in, for example, JP-A-5-225996(Pages 1 to 5, FIG. 2) as a fuel cell hydrogen recovery system which utilizes the MH.
As shown in FIG. 7, this fuel cell hydrogen recovery system includes a hydrogen absorbing/discharge means 100 for absorbing and discharging hydrogen substantially continuously under a desired pressure, and this hydrogen absorbing/discharge means 100 includes, in turn, two MH's 101, 102 which are adapted for absorbing or discharging hydrogen, an absorbing changeover means 103 and a discharge changeover means 104 which are adapted for implementing a changeover between a destination to which hydrogen is absorbed and an origin from which hydrogen is discharged as required and mixing means 105, 106 which are adapted for mixing heating water with cooling water at a predetermined ratio which allows the respective MH's 101, 102 to be set to a temperature corresponding to the desired pressure when the heating water and cooling water so mixed together is supplied to the MH's 101, 102.
According to this construction, there can be provided a fuel cell electricity generation system which can enable the stable and economic supply of hydrogen to the fuel cell and which can make the fuel cell smaller in size.
With the fuel cell hydrogen recovery system, however, in order to heat and cool the MH's 101, 102, there are provided the mixing means 105, 106 for mixing heating water with cooling water at the predetermined ratio which allows the respective MH's 101, 102 to be set to the temperature corresponding to the desired pressure, and moreover, special equipment such as a heater or a burner needs to be provided additionally as a heating device for causing recovered hydrogen to be discharged from the MH's.
In addition, since piping is required for supplying and discharging heating water and cooling water, the amount of heat that is dissipated to the outside of the system from the piping so provided becomes large, and this has been not preferable from the viewpoint of energy efficiency.


An antenna apparatus includes a horizontal polarization antenna element, and the horizontal polarization antenna element includes a radiation conductor that includes two conductor plates subjected to bending work and arranged to be opposite to each other with a specific interval therebetween and has a tube shape extending in a vertical direction in whole, a ground conductor that is arranged in an inner space surrounded by the two conductor plates of the radiation conductor and is electrically grounded, and a feeding element that is arranged in the inner space, is arranged along inner walls of the conductor plates in a top view, operates as a reverse L antenna when electrical power is fed between one end thereof and the ground conductor, and feeds power to the radiation conductor by electromagnetic coupling.

1. Field of the Invention
The present invention relates to an antenna apparatus.
2. Description of Related Art
In a base station of mobile communication such as a cellular phone or a PHS (Personal Handyphone System), since a service area is formed on a concentric circle whose center is the base station, an antenna apparatus with uniform directivity in the horizontal plane is used.
In general, in the antenna apparatus for the base station, it is desired that the antenna apparatus is made small in diameter and a construction for installing the antenna apparatus is made simple. An antenna element is desired which has a compact structure and enables the antenna apparatus to be made small in diameter.
A horizontal polarization antenna element (horizontal polarization omni element) shown in FIG. 20A and FIG. 20B is known to be used for an antenna apparatus (horizontal polarization omni antenna) in which the directivity of horizontal polarization in the horizontal plane is uniform.
In a horizontal polarization antenna element 200 shown in FIG. 20A, an arm portion (conductor portion) of a dipole antenna 201 horizontal to the ground is bent to form a compact structure.
A horizontal polarization antenna element 202 shown in FIG. 20B has a structure in which a patch antenna 203 bent in a rectangular shape is surrounded by parasitic elements 204. In the horizontal polarization antenna element 202, an electric wave radiated by the patch antenna 203 is shaped by the parasitic elements 204 and the directivity in the horizontal plane is uniformed.
When the horizontal polarization antenna element as shown in FIG. 20A or 20B and a vertical polarization antenna element having uniform directivity in the horizontal plane are arranged side by side and are disposed in an array shape, a polarization diversity omnidirectional antenna can be achieved.
An example of the related art includes JP-A-2010-62979.


The invention discloses a device for putting a sock or a shoe on or off. The device includes a long rigid arm with a distal end and a proximal end. The device includes a sleeve with its proximal end coupled to the distal end of the arm and a distal end of the sleeve including one or more tongues spaced apart by valleys that define sides of each tongue. At the proximal end of the arm is a right angle handle being broadly curved in a partly hooked shape, followed by a reverse bend to provide a short reverse end hook.

It has been recognized that clothes dressing activities, particularly actions of putting on or taking off socks and shoes which require articulation of back, spine, or other joints may be difficult for some persons. For example, people who are obese or who suffer from spine, back, hip, knee or any other lower body disorder/problem find it difficult to articulate their problem joint(s). This affects their ability to dress themselves with shoes or socks or any other accessory that requires articulation of a body part such as back or knee.
Various types of devices and apparatuses have become available to facilitate dressing of such as socks. However, those devices lack the comfort and easy to use component. Some of them facilitate dressing of socks but do not provide a way for removal of the socks from the body because of which a person may have difficulty during removal or pulling the socks off.
In light of the above, there is a need for a device that is simple and easy to use for pulling on as well pulling off the socks. In addition, the device may facilitate in several other usual tasks.


A method and system for a handoff in a broadcast communication system is disclosed. A subscriber assisted handoff is impractical in a broadcast communication system due to e.g., a high signaling load, a difficulty to synchronize the broadcast transmission. On the other hand, the small number of broadcast channels enables the subscriber station to perform the handoff autonomously. To streamline the autonomous handoff decision process, several distinct sets of pilot identifiers and rules for transitioning among the sets are defined. To fully integrate broadcast services with the services provided by the cellular telephone systems in a subscriber environment, a methods for various handoff scenarios are analyzed.

1. Field
The present invention relates to broadcast communications, otherwise known as point-to-multipoint, in a wireline or a wireless communication system. More particularly, the present invention relates to a system and method for a handoff in such a broadcast communication system.
2. Background
Communication systems have been developed to allow transmission of information signals from an origination station to a physically distinct destination station. In transmitting information signal from the origination station over a communication channel, the information signal is first converted into a form suitable for efficient transmission over the communication channel. Conversion, or modulation, of the information signal involves varying a parameter of a carrier wave in accordance with the information signal in such a way that the spectrum of the resulting modulated carrier is confined within the communication channel bandwidth. At the destination station the original information signal is replicated from the modulated carrier wave received over the communication channel. Such a replication is generally achieved by using an inverse of the modulation process employed by the origination station.
Modulation also facilitates multiple-access, i.e., simultaneous transmission and/or reception, of several signals over a common communication channel. Multiple-access communication systems often include a plurality of subscriber units requiring intermittent service of relatively short duration rather than continuous access to the common communication channel. Several multiple-access techniques are known in the art, such as time division multiple-access (TDMA), frequency division multiple-access (FDMA), and amplitude modulation multiple-access (AM). Another type of a multiple-access technique is a code division multiple-access (CDMA) spread spectrum system that conforms to the "TIA/EIA/IS-95 Mobile Station-Base Station Compatibility Standard for Dual-Mode Wide-Band Spread Spectrum Cellular System," hereinafter referred to as the IS-95 standard. The use of CDMA techniques in a multiple-access communication system is disclosed in U.S. Pat. No. 4,901,307, entitled "SPREAD SPECTRUM MULTIPLE-ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS," and U.S. Pat. No. 5,103,459, entitled "SYSTEM AND METHOD FOR GENERATING WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM," both assigned to the assignee of the present invention.
A multiple-access communication system may be a wireless or wire-line and may carry voice and/or data. An example of a communication system carrying both voice and data is a system in accordance with the IS-95 standard, which specifies transmitting voice and data over the communication channel. A method for transmitting data in code channel frames of fixed size is described in detail in U.S. Pat. No. 5,504,773, entitled "METHOD AND APPARATUS FOR THE FORMATTING OF DATA FOR TRANSMISSION," assigned to the assignee of the present invention. In accordance with the IS-95 standard, the data or voice is partitioned into code channel frames that are 20 milliseconds wide with data rates as high as 14.4 Kbps. Additional examples of a communication systems carrying both voice and data comprise communication systems conforming to the "3rd Generation Partnership Project" (3GPP), embodied in a set of documents including Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214 (the W-CDMA standard), or "TR-45.5 Physical Layer Standard for cdma2000 Spread Spectrum Systems" (the IS-2000 standard).
An example of a data only communication system is a high data rate (HDR) communication system that conforms to the TIA/EIA/IS-856 industry standard, hereinafter referred to as the IS-856 standard. This HDR system is based on a communication system disclosed in application Ser. No. 08/963,386, entitled "METHOD AND APPARATUS FOR HIGH RATE PACKET DATA TRANSMISSION," filed Nov. 3, 1997, now U.S. Pat. No. 6,574,211, issued on Jun. 3, 2003, assigned to the assignee of the present invention. The HDR communication system defines a set of data rates, ranging from 38.4 kbps to 2.4 Mbps, at which an access point (AP) may send data to a subscriber station (access terminal, AT). Because the AP is analogous to a base station, the terminology with respect to cells and sectors is the same as with respect to voice systems.
In a multiple-access communication system, communications between users are conducted through one or more base stations. A first user on one subscriber station communicates to a second user on a second subscriber station by transmitting data on a reverse link to a base station. The base station receives the data and can route the data to another base station. The data is transmitted on a forward link of the same base station, or the other base station, to the second subscriber station. The forward link refers to transmission from a base station to a subscriber station and the reverse link refers to transmission from a subscriber station to a base station. Likewise, the communication can be conducted between a first user on one subscriber station and a second user on a landline station. A base station receives the data from the user on a reverse link, and routes the data through a public switched telephone network (PSTN) to the second user. In many communication systems, e.g., IS-95, W-CDMA, IS-2000, the forward link and the reverse link are allocated separate frequencies.
When a subscriber station travels outside the boundary of the base station with which the subscriber station currently communicates, it is desirable to maintain the communication link by transferring the call to a different subscriber station. The method and system for providing a communication with a subscriber station through more than one base station during the soft handoff process are disclosed in U.S. Pat. No. 5,267,261, entitled "MOBILE ASSISTED SOFT HANDOFF IN A CDMA CELLULAR TELEPHONE SYSTEM," assigned to the assignee of the present invention. The method and system for providing a softer handoff is described in detail in U.S. Pat. No. 5,933,787, entitled "METHOD AND APPARATUS FOR PERFORMING HANDOFF BETWEEN SECTORS OF A COMMON BASE STATION," assigned to the assignee of the present invention. Using these methods, communication between the subscriber stations is uninterrupted by the eventual handoff from an original base station to a subsequent base station. This type of handoff may be considered a "soft" handoff in that communication with the subsequent base station is established before communication with the original base station is terminated. When the subscriber unit is in communication with two base stations, the subscriber unit combines the signals received from each base station in the same manner that multipath signals from a common base station are combined.
In accordance with the above-cited inventions, each base station transmits a pilot signal of a common PN spreading code offset in code phase from pilot signals of other base stations. A subscriber station assisted soft handoff operates based on the pilot signal strength detected by the subscriber station. To streamline the process of searching for pilots, four distinct sets of pilot offsets are defined: the Active Set, the Candidate Set, the Neighbor Set, and the Remaining Set. The Active Set identifies the base station(s) or sector(s) through which the subscriber station is communicating. The Candidate Set identifies the base station(s) or sector(s) for which the pilots have been received at the subscriber station with sufficient signal strength to make them members of the Active Set, but have not been placed in the Active Set by the base station(s). The Neighbor Set identifies the base station(s) or sector(s), which are likely candidates for the establishment of communication with the subscriber station. The Remaining Set identifies the base station(s) or sector(s) having all other possible pilot offsets in the current system, excluding those pilot offsets currently in the Active, the Candidate and Neighbor sets.
The subscriber station is provided with a list of PN offsets corresponding to base stations of neighboring cells. In addition, the subscriber station is provided with a message which identifies at least one pilot corresponding to a base station to which the subscriber station is to communicate through. These lists are stored at the subscriber station as a Neighbor Set and an Active Set of pilots, and are updated as conditions change.
When communication is initially established, a subscriber unit communicates through a first base station and the Active Set contains only a pilot signal of the first base station. The subscriber unit monitors pilot signal strength of the base stations of the Active Set, the Candidate Set, the Neighbor Set, and the Remaining Set. When a pilot signal of a base station in the Neighbor Set or Remaining Set exceeds a predetermined threshold level (T_ADD), the pilot signal identifier is added to the Candidate Set. The subscriber unit communicates a Power Strength Measurement Message (PSMM) to the first base station identifying the new base station. A system controller decides whether to establish communication between the new base station and the subscriber unit, and communicates the decision in a Handoff Direction Message (HDM). The message identifies the pilots of the Active Set which correspond to base stations through which the subscriber station is to communicate. The system controller also communicates information to each base station corresponding to a new pilot in the Active Set which instructs each of these base stations to establish communications with the subscriber station. The subscriber station communications are thus routed through all base stations identified by pilots in the subscriber station Active Set.
When the subscriber unit is communicating through multiple base stations, it continues to monitor the signal strength of the base stations of the Active Set, the Candidate Set, the Neighbor Set, and the Remaining Set. Should the signal strength corresponding to a base station of the Active Set drop below a predetermined threshold (T_DROP) for a predetermined period of time (T_TDROP), the subscriber unit generates and transmits a message to report the event. The system controller receives this message through at least one of the base stations with which the subscriber unit is communicating. The system controller may then decide to terminate communications through the base station whose pilot signal strength as measured at the subscriber station is below the T_DROP.
The system controller upon deciding to terminate communications through a base station generates a new message identifying the pilots of the Active Set to which the subscriber station is to communicate through. In this message, which identifies pilots of the Active Set, the pilot of the base station to which communications with the subscriber station are to be terminated is not identified. The system controller also communicates information to the base station not identified in the Active Set to terminate communications with the subscriber station. The subscriber station, upon receiving the message identifying pilots of the Active Set, discontinues processing signals from the base station whose pilot is no longer in the Active Set. The subscriber station communications are thus routed only through base stations identified by pilots in the subscriber station Active Set. In the case where there were previously more than one pilot identified in the Active Set and now only one, the subscriber station communicates only to the one base station corresponding to the pilot identified in the subscriber station Active Set.
The above-described wireless communication service is an example of a point-to-point communication service. In contrast, broadcast services provide central station-to-multipoint communication service. The basic model of a broadcast system consists of a broadcast net of users served by one or more central stations, which transmit information with a certain contents, e.g., news, movies, sports events and the like to the users. Each broadcast net user's subscriber station monitors a common broadcast forward link signal. Because the central station fixedly determines the content, the users are generally not communicating back. Examples of common usage of broadcast services communication systems are TV broadcast, radio broadcast, and the like. Such communication systems are generally highly specialized purpose-build communication systems. With the recent, advancements in wireless cellular telephone systems there has been an interest of utilizing the existing infrastructure of the mainly point-to-point cellular telephone systems for broadcast services. (As used herein, the term "cellular" systems encompasses communication system utilizing both cellular and PCS frequencies.)
Although the described handoff method for subscriber units acting as point-to-point units described above could be applied to broadcast systems, because in a broadcast system, large number of subscribers monitor a common broadcast forward channel, a handoff based on base station-subscriber station signaling message exchange would result in a high signaling load. Furthermore, as described in the above-cited U.S. Pat. Nos. 5,267,261, and 5,933,787, the transmissions received simultaneously by a subscriber station during handoff are synchronized at the transmitting base stations. Because broadcast transmission is intended for many subscriber stations, the base station cannot synchronize transmission for each subscriber station desiring to handoff. Based on the foregoing, there is a need in the art for a system and method for handoff in such a broadcast communication system.

This patent is subject to a terminal disclaimer.

Method and system for a handoff in a broadcast communication system


The present invention provides a novel process for the preparation of sorafenib tosylate polymorph III.

Sorafenib, chemically 4-{4-[({[4-chloro-3-(trifluoromethyl)phenyl]amino}-carbonyl)amino]phenoxy}-N-methyl-2-pyridinecarboxamide and has the structural formula:

Sorafenib tosylate is a well-known antineoplastic agent, and was useful for the treatment of primary kidney cancer (advanced renal cell carcinoma) and advanced primary liver cancer (hepatocellular carcinoma). The generic name sorafenib tosylate is marketed by Bayer Healthcare under the brand name NEXAVAR®.
Sorafenib was disclosed in International application publication no. WO 2000/042012.
Sorafenib tosylate was disclosed in International application publication nos. WO 2003/068228 and WO 2003/047579.
International application publication no. WO 2006/034797 described Polymorph I, Polymorph II, Polymorph III, methanol solvate and ethanol solvate of sorafenib tosylate. According to the publication, sorafenib tosylate polymorph III can be prepared by suspending sorafenib tosylate in methanol at room temperature, maintained for one week and then filtered to obtain a residual solid. The residual solid was heat-treated at 150° C. for 30 minutes to obtain sorafenib tosylate polymorph III.
Process for the preparation of sorafenib tosylate polymorph III was disclosed in International application publication no. WO 2009/092070. According to the publication, sorafenib tosylate polymorph III can be prepared by providing a suspension comprising sorafenib tosylate and a solvent selected from methanol, a mixture of methanol and N-methyl-2-pyrrolidone, a mixture of methanol and dimethyl sulfoxide to obtain sorafenib tosylate methanol solvate and then drying the sorafenib tosylate methanol solvate at 80 to 90° C.
We have found a novel process for the preparation of sorafenib tosylate polymorph III.
Thus, an object of the present invention is to provide a novel process for the preparation of sorafenib tosylate polymorph III.
Powder X-ray diffraction spectrum was measured on a bruker AXS D8 advance powder X-ray diffractometer having a copper-Kα radiation. Approximately 500 mg of sample was gently flattered on a sample holder and scanned from 2 to 50 degrees two-theta, at 0.020 degrees two theta per step and a step time of 1 second. The sample was simply placed on the sample holder. The sample was rotated at 30 rpm at a voltage 40 kV and current 35 mA.

Process for sorafenib tosylate polymorph III


A cooling cap (1) made up with knitted net fabric of polyester yarn comprises an outer open-meshed fabric (3) for covering the front half part of the hemispheric part of the cap to receive the human head, an inner fine linen fabric (4) for lining the outer open-meshed fabric, a water absorbent fiber layer (5) for bearing water or absorbing sweat, and a plurality of eyelets or loopholes (6). The head is cooled owing to the vaporization of the water borne in the water absorbent fiber layer by absorbing the heat.

The present invention concens a summer cap made of open-meshed fabric of polyester yarn. There have been developed many varieties of the cap; one of which is the summer cap having a large visor to shield the summer daylight or made of open-meshed fabric to make ventilation. However, such summer cap has no positive means to effectively cool the head of a person working in the field, so that the worker must suffer the heat of the sun or other high temperature environment (e.g. steel mill) or where the user generates heat by exertion, e.g. exercise, manual labor.

Apku Jong-dong, Kangnam-Ku, Seoul 135-112


A wear-resistant tool insert for machines used in the manufacture of nails, screws, rivets and similar items from a wire starting material. The tool insert is of divided design in the axial direction of the supplied wire. Thus, during application of the tool insert it can "flex" in a controlled manner thereby reducing tensile stress in the tool insert, and reducing the possibility of fracture or breakage of the tool insert, when employed in an overload condition with unacceptably large tensile loads.

1. Field of the Invention
This invention pertains to a wear-resistant tool insert for machines used in the production of nails, screws, rivets and similar objects starting with wire material.
2. Description of Related Art
Wear-resistant tool inserts of this type are employed in pairs in machines and are called impact or clamping jaws and pincer jaws. The clamping jaws are often used as inserts in toolholders. The inserts have elongated, prism-like trapezoidal cross-section base elements corresponding to similar recesses in the toolholders. One working surface of the clamping jaws has one or more clamping grooves for tightly clamping the supplied wire, and also a recess for forming the desired head shape of the object to be produced. The clamping jaws are arranged in the machine so that the clamping grooves are located opposite the paired inserts. In the course of the machine operation, the clamping jaws are closed or opened. In the closed state, the supplied wire is tightly clamped in the clamping grooves. In the clamped state, the head of the nail, screw or rivet is formed. For better clamping of the supplied wire, the clamping grooves are preferably transverse and semicircular in form.
After completion of the head, the part is elongated by closing two opposing pincer jaws. The pincer jaws are clamped tightly in toolholders or directly in the machine. They have a symmetrical profile with several cuts, through which, on the one hand, the end of the finished part is shaped and the part is elongated, and on the other at the same time, the initial geometry is created to shape the head of the next part.
A distinction is made, between single-wire and dual-wire clamping jaws, where either one or two clamping grooves are provided side by side.
The dual-wire form makes possible a simultaneous production of two nails, screws or rivets, that is, the production capacity is doubled. The pincer jaws are, as a rule, always of single-wire design, so that four pincer jaws are used in association with two-wire clamping jaws.
The tool inserts are often manufactured of hard metal to reduce wear. If the wear on the clamping grooves or on the cutters is excessive, then the inserts must be replaced.
Hard metal and other hard, wear-resistant materials indeed have a high compression strength and a very great hardness and thus a great wear resistance, but they can withstand only moderate tensile and bending loads. Based on irregularities in wire quality in connection with varying dimensions or different strengths in the manufacture of nails, screws, or rivets, very large tensile loads, and thus over stressing of the inserts of wear-resistant material may occur, which often is associated with fracturing of the inserts.


A new substance BPC; the process for its preparation from human and animal gastric juice comprising purifications steps: centrifugalization, dialysis, ion-exchange, chromotagraphy, gal chromatography and lyophilisation; a drug for human and veterinary use and a process for the treatment of stress-induced diseases and disorders, inflammation and edemas, diseases and disorders of dopaminergic etiology, for treatment of diabetes mellitus, diseases and disorders of gastrointestinal tract, heart, kidney, pancreas, liver, testis, hematopoetic, skeletal and nervous, system, dementias, wound, burns, fracture, viral diseases, malignancy; in surgery; some disorders of fertility and immune system; protection against ionizing radiation; for veterinary use in commercial breeding.

1. Field of the Invention
The present invention relates to a new substance BPC, the process for its preparation from human or animal gastric juice and its use in the therapy.
2. Description of the Prior Art
Gastric juice, considered as a secretion of the parietal as well as other cells, contains a number of electrolyte components, hydrochloric acid, a number of enzymes, namely, pepsin, other proteinases, rennin, lipase, urease and lysozyme. There are present many peptides and peptide fragments, e.g. peptide hormones gastrins, a highly potent gastric secretion stimulants, first discovered by J. S.Edkins, Proc.Roy.Soc.L., 76B, 376 (1905).
In normal gastric juice are present glycoproteins (mucins), desribed by F.Hanrowitz, Chem. and Biology of Proteins, 1950, p.199., and Intrinsic Factor (IF), which is a thermolabile mucoprotein with M.W. about 60.000. This factor promotes vitamin B.sub.12 absorption, Castle et al, Am.J.Med Sci. 178, 748 (1929).
Till now, a substance having very strong antistress actions and other body-protection activities was not found in gastric juice.

Pharmacologically active substance BPC, the process for its preparation and its use in the therapy


A toner consumption amount identifying unit identifies a toner consumption amount of toner consumed in a printing process from the print data. A toner residual amount identifying unit identifies a toner residual amount in a toner container from the toner consumption amount. A toner residual amount data managing unit stores order-timing toner residual amount data into a non volatile memory device at a timing when an ordering process of the toner container succeeds, and deletes the order-timing toner residual amount data in the non volatile memory device if the value of the toner residual amount is larger than a value of the order-timing toner residual amount data. An order processing unit performs the ordering process if the order-timing toner residual amount data is not stored in the non volatile memory device and the value of the toner residual amount is either equal to or less than a predetermined value.

1. Field of Present Disclosure
The present disclosure relates to an image forming apparatus and a toner container ordering method.
2. Description of the Related Art
In an image forming apparatus, a development is performed with toner provided from a toner container for printing. In an image forming apparatus, a toner residual amount in a toner container is estimated from an output of a physical sensor, and if the toner residual amount reaches a predetermined value or less, then a near empty status of the toner residual amount is informed and an order of a toner container is placed.
When the toner residual amount is estimated from an output of a physical sensor as mentioned, an estimation error at a low toner residual amount is large due to uneven distribution of toner in a toner container and so forth.
Usually, when the near empty status is informed, a user prepares a new toner container. However, when the near empty status is informed of a toner container, in order to fully use residual toner, some users detach and shake the toner container, and then reattach the toner container to the apparatus. This operation may cancel the uneven distribution of toner in the toner container and consequently may increase the toner residual amount value estimated from the sensor output and may temporarily cancel the near empty status. In such a case, the near empty status is detected afterward, the near empty status is informed again.
Therefore, if at the near empty status the toner container is detached and reattached, then the near empty status is detected plural times, and consequently for one toner container, plural orders of toner containers are redundantly placed.

Image forming apparatus and toner container ordering method


A mold and a method for molding high strength, non-metallic fiber reinforced composite parts having a variety of (e.g., cylindrical) shapes that are lighter in weight than similar parts manufactured from metal. An unmolded non-metallic pre-form having long continuous fibers is placed around a mandrel, and a segmented, adjustable diameter compression ring is disposed in surrounding engagement with the pre-form at an upper position within an inwardly tapered compression ring support. The compression ring is formed from a plurality of loose compression ring segments that are initially spaced circumferentially from one another at the upper position of the compression ring support. The mandrel and the pre-form are first heated and then located in a press. The press is closed to push the compression ring and the heated mandrel from the upper position of the compression ring support, at which the compression ring has an open configuration and a wide diameter, to a lower position, at which the compression ring has a closed configuration and a narrow diameter. As the compression ring is pushed to the lower position, the compression ring segments slide along the inwardly tapered compression ring support so as to be moved end-to-end one another to apply a compressive force for consolidating and shaping the heated pre-form into the molded part.

1. Field of the Invention
This invention relates to a mold including a segmented adjustable diameter compression ring and a tapered compression ring support and to a method for molding high strength, non-metallic fiber reinforced composite parts having a variety of different shapes to be substituted for heavier metal parts.
2. Background Art
Parts such as fasteners, connectors, couplers, and the like, have long been manufactured from metal. Such metal parts have been used in aircraft and similar applications because of their high strength characteristics. However, these same metal parts are known to be relatively heavy. Consequently, in cases where a very large number of metal parts are used, the overall weight of the aircraft will be increased with the result that the performance (e.g., fuel consumption and speed) of the aircraft may be adversely affected.
To overcome this problem, designers have been making the same parts from non-metallic fiber reinforced material. In this case, an injection molding process is commonly used to manufacture relatively lightweight parts that are reinforced with short milled fibers. Nevertheless, it has been found that such short milled fiber reinforced parts lack the tensile and shear strength that is required to withstand extreme physical forces that are typically encountered by aircraft traveling at high speeds and high altitudes. Conventional injection molding techniques are not applicable to making non-metallic parts that are reinforced with long and continuous fibers which would advantageously increase the ultimate strength of the final parts.

Method and mold for making non-metallic fiber reinforced parts


The invention provides a vacuum gate valve for closing off an opening. The vacuum gate valve can have a valve plate that can be turned so that the alignment of the valve plate will adapt to a valve seat when the valve plate is pressed against the valve seat.

Vacuum gate valves are used to close off an opening in a container or pipeline. Vacuum gate valves primarily of the L-type are utilized in IC and semiconductor manufacturing to exclude, to a large extent in a protected atmosphere, the presence of contaminating particles. For instance, in a production unit for semiconductor wafers or liquid-crystal substrates, the highly sensitive semiconductor or liquid-crystal elements pass through a number of production chambers each of which can be connected to the next via a connecting passage. These passages are opened via vacuum gate valves so that the elements can be transferred from one production chamber to the next and then closed again in gas-tight fashion so that continuing production steps can be performed.
A general schematic of a related art vacuum gate valve is illustrated in FIGS. 1a, 1b and 1c.
FIG. 1a shows the vacuum gate valve in its opened initial position. The vacuum gate valve can have a valve housing 1 with a wall 2 having an opening 3 (e.g. of rectangular shape). A valve seat 4 formed as a flat surface or a surface of special shape, with or without a seal, surrounds the opening 3. A valve plate 5, which in the opened initial position of the vacuum gate valve is positioned in a lateral position to the opening 3, close to the wall 2, is shown in FIG. 1a. The valve plate 5 has a shape, more particularly rectangular, which overlaps the opening 3 in such a way that the opening can be closed off entirely with a sealing face 7 of the valve plate 5. The valve plate 5 is mounted on a valve rod 8 defining a valve rod axis 11. Instead of one single valve rod 8, two parallel valve rods can be can utilized.
The valve rod 8 can essentially be controlled along two degrees of freedom by control organs 10, for instance by a hydraulic-cylinder and swivel-gear unit, as will subsequently be shown in FIGS. 1b and 1c. More particularly the valve rode 8 can be shifted linearly along the valve rod axis 11 and swivelled in a plane normal to wall 2.
In related art systems, closing off the opening 3 is done in two steps. In a first step, occurring between the situations shown in FIGS. 1a and 1b, the valve rod 8 is extended by means of the control organs 10 along the valve rod axis 11, which is shown by two arrows 28a and 28b. The valve plate 5 is moved over the opening 3 along a path essentially parallel to the wall 2 while avoiding contact between the valve plate 5 and the wall 2 or the valve seat 4 of the valve housing 1.
In a second step, occurring between the situations of FIGS. 1b and 1c and symbolically represented by the arrow 28c, the valve rod 8 is swivelled toward the wall 2 by the control organs 10, so that the sealing face 7 of the valve plate 5 (which may for instance hold a sealing ring) is pressed against the valve seat 4 and the opening is closed off firmly, where applicable in a gas-tight fashion. Sealing can be realized, for instance, either via a sealing ring disposed on the sealing face 7 of valve plate 5 and pressed against the valve seat 4 surrounding the opening 3, or via a sealing ring disposed on valve seat 4 against which the sealing face 7 of the valve plate 5 is pressed. The valve seat 4 is generally defined as the opposing face on wall 2 onto which the sealing face 7 of valve plate 5 is pressed, and which thus causes the sealing.
Different sealing devices are known from the related art, for instance from U.S. Pat. No. 6,629,682 B2. The elastic sealing material known under the trade name of Viton®, for instance, is a suitable material for sealing rings. In view of the closing operation occurring in two steps, the sealing ring will hardly be subjected to any shear forces that might destroy it, since the swivelling motion of the valve rod 8 causes an essentially straight-line movement of the valve plate 5 normal to the valve seat 4. From the related art, various kinds of control organs 10 are known which each may give rise to a slightly different direction of control of valve rod 8 and thus of the valve plate 5. Thus, instead of an arched swivel path of valve plate 5 toward valve seat 4, an absolutely linear motion of the valve plate 5 normal to wall 2 can be initiated. Diverse embodiments of vacuum gate valves of the kind cited above are known, for instance, from U.S. Pat. Nos. 6,431,518 B1, 5,415,376 A, 5,641,149 A, 6,045,117 A, 5,934,646 A, 5,755,255 A, 6,082,706, 6,095,180 and 6,629,682 B2.
A particular problem in the related art is the alignment of valve plate 5 relative to valve housing 1. In the first step, moving the valve plate 5 over the opening 3, contact of the sealing face 7 with wall 2 or valve seat 4 can lead to injury to a sealing surface or to the sealing ring. Additionally, in the second step, where pressure is applied, the valve plate 5 should have a precise alignment relative to the valve seat 4, since otherwise the sealing face 7 of the valve plate 5 may not reach its precise position on the valve seat 4.
In related art systems the planes of sealing face 7 and valve seat 4 should be parallel while the pressure is applied, since otherwise the sealing surface along the valve seat would be stressed non-uniformly, which could give rise to poor tightness and to a degradation of the sealing material. Moreover, the valve plate 5 and the valve rod 8 would be subjected to bending and torsional forces. For this reason, control organs 10 in the related art attempt to precisely align the valve rod 8, and thus the valve plate 5.
The joint between valve rod 8 and valve plate 5 is formed for instance by means of a connecting segment 9 on valve rod 8 which is guided into and fastened inside a receptacle 6 formed in valve plate 5. The fastening occurs for instance as described in U.S. Pat. Nos. 6,068,180 and 6,619,618, namely by means of at least one screw inserted from the side opposite to the sealing face.
U.S. Pat. No. 6,619,618 illustrates a vacuum gate valve which has a valve plate of non-uniform wall thickness, viz., thicker in the middle than in the two lateral zones. In the central, thick-walled zone, a semicircular receptacle for a valve rod is formed, the wall thickness between the receptacle and the sealing face being large relative to the wall thickness between the receptacle and the face opposite to the sealing face. The valve rod, at its end, has a connecting segment which also is semicircular, and is introduced into the receptacle. The valve plate is solidly mounted onto the valve rod by means of a screw, screwed in from the side opposite to the sealing face. With the design of valve plate, receptacle and connecting segment, as described in U.S. Pat. No. 6,619,618, it is intended to avoid excessive bending of the valve plate when pressed onto the valve seat, particularly in the lateral zones of an elongated valve plate, without the need for more than a single shaft or larger overall thickness of the valve plate.
In related art systems, the valve plate 5 is subjected to controls or maintenance at certain time intervals, particularly for checking or replacing the sealing ring, in order to attempt to increase the lasting tightness of the vacuum gate valve. With the vacuum gate valves known from the related art, the demounting and re-mounting of the valve plate is found to be difficult, since an intervention from several sides of the valve plate is required to detach the valve plate from the valve rod, e.g. in order to unfasten any mounting screw and take off the valve plate from the valve rod. A safe demounting is not readily achieved without injury to the valve plate 5 or valve housing 1, and particularly the valve seat 4, because of poor ergonomic possibilities for handling the valve plate.


A package for providing electromagnetic shielding for microwave circuits. The package includes a top board having an upper surface, a lower surface opposite to the upper surface and a side surface joining the upper surface and the lower surface, and a bottom board having an upper surface attached to the lower surface of the top board, a lower surface opposite to the upper surface and an outer side surface joining the upper surface and the lower surface. The top board further includes at least one ground layer formed therein and a first metal coating formed on at least part of the side surface of the top board. The bottom board includes an inner side surface extending from the upper surface of the bottom board toward the lower surface of the bottom board and an inner lower surface joining the inner side surface, thereby providing an inner space for accommodating the microwave circuit. The bottom board further includes a second metal coating formed on at least part of the outer side surface of the bottom board and a third metal coating formed on at least part of the lower surface of the bottom board. The ground layer, the first metal coating, the second metal coating and the third metal coating are electrically coupled to provide an electric shield for the microwave circuit.

Microwave and millimeter-wave products, such as motion detectors, are commonplace in home and industry applications. Microwave energy has many other types of applications. For instance, microwave energy is used for radar, broadcast radio and television, meteorology, satellite communications, distance measuring, and mobile phones, to name a few.
In the process of manufacturing microwave and millimeter-wave products using planar circuit approaches, the packaging process is critical because it affects the properties of the products, such as the cost of products, the performances of the products, the weight of the products and the applicability of the products.
Traditionally, due to the sensitive characteristics of microwave and millimeter-wave signals, it is necessary to mount the circuit boards into a shielded cavity during packaging the microwave or millimeter-wave circuits, in order to prevent the signals from being interfered by environmental signals or noises, such as signals transmitted from nearby electronic devices, e.g., a cordless telephone utilizing the same or similar frequency band for the transmission of communication information. This step renders the entire structure of the microwave or millimeter-wave module including the circuit boards and the cavity housing the circuit boards complex and, accordingly, increases the costs of manufacturing.
Thus, it would be advantageous to provide a package for providing an electromagnetic shielding for a microwave circuit, which is capable of avoiding interferences with the environment signals and noises within the vicinity of the microwave circuit as well as simplifying the manufacturing procedures, and a method for manufacturing the package.

Package for electronic component and method for manufacturing the same


Bond pad lift problems encountered during bonding are alleviated by providing an upper bond pad, a lower bond pad and an insulating component between the upper and lower bond pads. At least one opening is provided through the insulating component, extending from the bottom bond pad to the upper bond pad. The at least one opening is aligned with a peripheral region of the bottom bond pad. Conductive material fills the at least one opening, and electrically connects the top and bottom bond pads. In one embodiment, the at least one opening is a plurality of conductive vias. In another embodiment, the at least one opening is a ring-like opening extending around the peripheral region. In yet another embodiment, the at least one opening is one or more elongated slit-like openings.

Integrated circuit devices comprise a semiconductor die having a variety of diffusions and overlying layers forming circuit elements, gates and the like. Generally, the penultimate layers fabricated on the die are conductive metal layers ("M") having patterns of conductive lines. Two or more metal layers ("M1", "M2", etc.) are separated by a dielectric layer of inter-layer dielectric (ILD). For purposes of this discussion, it is assumed that there are two conductive layers, a layer designated "M1", and a layer designated "M2". An ILD layer overlies the M1 layer, and the M2 layer overlies the ILD. Typically, a topmost passivation layer is applied over the M2 layer. Openings through this passivation layer expose areas of the M2 layer. These exposed areas are termed "bond sites". Connections to the die, hence to the circuitry contained on the die, are effected with these exposed areas. For example, bond wires may be bonded directly to the bond sites, or gold bumps may be formed on the bond sites for tape-automated bonding to the die, or gold balls may be formed on the exposed areas for flip-chipping the die to a substrate. This is all well known.
FIGS. 1A and 1B illustrate the structure of a prior art "composite bond pad" 100. Typically, a plurality of such bond pads would be disposed on a die. A partially-fabricated semiconductor die 102, having various diffusions and depositions (not shown), has a top surface 103. A layer 104 of insulating material (e.g., silicon dioxide) is formed on the surface 103. A patterned layer 106 of "barrier metal" is applied over the oxide 104. A patterned conductive layer 108 of "first" metal ("M1") is applied over the barrier metal 106, and is connected (not shown) to circuit elements (not shown) contained on the die. A layer 110 of inter-layer dielectric ("ILD"; e.g., silicon dioxide) is applied over the first metal layer 108, and is provided with an opening 112 extending through the layer 110 to the top surface (as viewed in the Figure) of the underlying M1 layer. A patterned conductive layer 114 of "second" metal ("M2") is applied over the ILD 110, and a portion 116 of this layer 114 forms a conductive "plug" filling the opening 112. A topmost "passivation" layer 118 (e.g., Borophosphosilicate Glass, or BPSG) is applied over the M2 and ILD layers, and is provided with an opening 120 extending through the passivation layer 118 to the top surface (as viewed in the Figure) of the underlying M2 layer. This leaves an area 120 of the top surface of the M2 layer exposed. The area 120 is termed the "contact area" ("bond site"). It is in this contact area that external connections to the die will be made, by any suitable means such as bond wires. Alternatively, gold bumps (not shown) or gold balls (not shown) can be formed atop the area 120, for tape-automated (TAB) bonding or flip-chip bonding to the die.
In aggregate, the elements 114, 116 and 108 comprise the "composite bond pad" 100. For purposes of this discussion, the portion of the metal layer 114 above dashed line 115 is termed "upper bond pad", and the portion of the lower metal layer 108 underlying the upper bond pad is termed "lower bond pad". The use of a barrier metal layer (106) underneath the bond pad (i.e., underneath the M1 layer) is optional, and offers certain protection against diffusion into the M1 layer of "fugitive" species (contaminants, vis-a-vis the M1 layer) from underlying layers in the die.
As best viewed in FIG. 1B, the (composite) bond pad 100 is generally square (it is shown in the Figure as a slightly elongated rectangle), and has dimensions on the order of 100.times.100 .mu.m (microns). Further, the upper bond pad may be larger than the "plug" 114. For example, if the upper bond pad measures 100 .mu.m across, the plug may measure only 80-90 .mu.m across. As is evident, only the outer peripheral region (for example the outermost 10% of the upper bond pad) of the upper bond pad rests on the ILD 110.
In practice, the lower bond pad element 108 may be a defined portion (shown as a slightly elongated rectangle) of a conductive line of the M1 layer.
In practice, a plurality of bond pads (100) are disposed on the top surface of the die, for making a plurality of input/output (I/O) connections to the die.
As mentioned above, ultimately the contact area 120 is bonded to, whether with a bond wire, or by the mechanism of gold bumps/balls. These various processes typically impart mechanical and or thermal energy directly onto the bond pad, especially in the contact area. It has been observed that these bonding processes, can cause the bond pad to delaminate (lift) from the underlying surfaces of multiple metal layers (e.g., 106) and oxide (e.g., 104). This bond pad lift problem can happen in all different kinds of bonding technology, such as aluminum wire bond, gold ball bonding, gold bump bonding, and others. This bond pad lift problem can become exacerbated when using an underlying layer of barrier metal (106), such as titanium (Ti), titanium nitride (TiN), Titanium-Tungsten (TiW), and the like, under the bond pads. Bond pad lift is very undesirable, and can result in potential problems in both assembly (packaging) yield and device reliability.
In the past, efforts to alleviate bond pad lift have been directed to: (1) adjusting bonding process parameters to minimize the thermal and/or mechanical shock to the bond pad; and (2) optimizing the barrier metal layer materials and deposition technology. These efforts have met with only partial success, and impose undesirable constraints (i.e., a narrow window of process parameters) on the bonding process.


A drive force control method for a four-wheel drive vehicle having front wheels as main drive wheels always connected to a driving source, rear wheels as auxiliary drive wheels whose drive torque is adjustable, and a mechanism capable of adjusting a torque distribution ratio between the front wheels and the rear wheels so that the torque distribution ratio of the rear wheels to the front wheels is increased in turning and also capable of adjusting a torque distribution ratio between the right and left rear wheels in turning. The drive force control method includes the steps of detecting a vehicle speed, and gently decreasing the torque distribution ratio of a turning outer wheel to a turning inner wheel with an increase in the vehicle speed. When the transmission shift position is a low-speed position or a high-speed position or the vehicle is in reverse running, the torque distribution ratio of the turning outer wheel to the turning inner wheel is decreased.

1. Field of the Invention
The present invention relates to a drive force control method for a four-wheel drive vehicle.
2. Description of the Related Art
In the case of turning a corner having a small turning radius in a four-wheel drive mode of a four-wheel drive vehicle in a low to medium vehicle speed range, a difference in rotational speed due to a difference in turning radius is generated between the front and rear wheels of the vehicle, causing a tight corner braking phenomenon. As the prior art for eliminating such a tight corner braking phenomenon, front and rear wheels driving devices are disclosed in Japanese Patent Publication Nos. 7-61779 and 7-64219.
The front and rear wheels driving devices disclosed in these publications have such a structure that a speed increasing device is provided between main drive wheels and auxiliary drive wheels to thereby adjust an average rotational speed of the auxiliary drive wheels to an average rotational speed of the main drive wheels. This speed increasing device includes a lockup clutch and a speed increasing clutch, which are selectively switched between ON and OFF states to thereby obtain a lockup condition or same speed condition where the average rotational speed of the main drive wheels and the average rotational speed of the auxiliary drive wheels are substantially equal to each other or an increasing speed condition where the average rotational speed of the auxiliary drive wheels is greater than the average rotational speed of the main drive wheels.
Particularly in the front and rear wheels driving device disclosed in Japanese Patent Publication No. 7-61779, a torque distribution ratio between right and left rear wheels are controlled according to a vehicle speed and a steering angle so that the rear wheel torque is larger than the front wheel torque and the turning outer wheel torque is larger than the turning inner wheel torque. In this front and rear wheels driving device, the auxiliary drive wheels are increased in rotational speed by the speed increasing device in turning a corner having a small turning radius in the four-wheel drive mode, thereby preventing the tight corner braking phenomenon.
The object of distributing a drive force between right and left wheels in turning is to give a larger drive force to the outer wheel as compared with the inner wheel, thereby generating a turning moment to suppress understeer occurring at acceleration during turning. However, the expectable effect of the drive force distribution between right and left wheels may vary according to a vehicle speed. For example, there is a tendency to desire stabilization of a vehicle body rather than improvement in maneuverability by giving a large turning moment at high vehicle speeds. However, minute control of the drive force distribution between right and left wheels according to a vehicle speed is not sufficiently disclosed in the above publications.
By distributing a driving/braking force generated by an engine in a four-wheel drive vehicle between front wheels and rear wheels, the load on each wheel can be controlled to maximize the utilization of tire performance. Particularly at acceleration of a two-wheel drive vehicle, a drive force so large as to cause skid of the wheels is generated. It is therefore very effective to make the two-wheel drive vehicle into a four-wheel drive vehicle.
In also taking a turning performance into consideration, the performance can be improved by changing the drive force distribution ratio between front and rear wheels so that the drive force distributed to the rear wheels is greater than that to the front wheels. However, when a vehicle speed is increased, a drive force and an engine brake force generated by a vehicle body are decreased in general, so that the effect of changing the drive force distribution ratio between front and rear wheels is small. Changing the torque distribution ratio of rear wheels to front wheels according to a vehicle speed, accelerator opening, transmission shift position, etc. is not sufficiently described in the above publications.

Drive force control method for four-wheel drive vehicle


A security checkpoint includes a personal scanning portal, a parcel scanning portal and a controller for ensuring substantially simultaneous scanning of a person and the parcel associated with the person. The controller also adjusts the level of scrutiny at each portal based on scanned data received at the other portal and based on information in a database relating to the specific person at the security checkpoint.

1. Field of the Invention
The invention relates to apparatus for coordinated screening of passengers and packages at security checkpoints.
2. Description of the Related Art
Many different types of devices have been developed for screening both people and parcels for weapons and other contraband. These are used at airports, government buildings and other high security locations. Additionally, security personnel employed at these locations have been trained to identify certain personal characteristics that may trigger a more detailed security investigation. For example, airline passengers may be subjected to a visual screening at the ticket check-in counter. The visual screening will assess the demeanor and nervous state of the passenger, the itinerary of the passenger, the method of payment for the ticket and in some instances the ethnicity of the passenger. A ticket agent may mark a boarding pass with a code that requests additional screening at a later checkpoint if the preliminary screening by the ticket agent suggests that a more detailed security review is appropriate.
The passenger then moves from the ticket counter to a security checkpoint between the ticket counter and the boarding gate. The typical security checkpoint requires the passenger to walk through a metal detector. Some airports also have a walk through detector that checks for the presence of trace amounts of substances of interest. One such detector is disclosed in U.S. Pat. No. 6,073,499 and is effective to determine whether the passenger is carrying or has recently handled explosives or narcotics. The passenger then proceeds towards the gate. All airlines require the passenger to show a boarding pass at the gate and perhaps some other form of identification. The boarding pass may have been marked by the ticket agent in a manner to indicate a need for further searching. In such cases, the passenger may be subject to increased scrutiny by being directed down a separate "selectee" lane at the checkpoint.
At the security checkpoint, carry-on luggage is placed on a conveyor belt and passed through an X-ray inspection apparatus shortly before the passenger walks through the metal detector. The conveyor belt of the X-ray inspection apparatus operates continuously unless stopped by the security personnel viewing the screen of the X-ray inspection apparatus. If necessary, the conveyor may be operated in reverse so that a piece of luggage can be re-inspected if the security personnel think they have seen an object that requires more than the initial passing glance. Many passengers have several items of carry-on luggage that are subject to X-ray inspection. The movement of these personal items of luggage through the X-ray inspection apparatus is performed entirely independently of the movement of the passenger through the metal detector. For example, a person will be delayed from entering the metal detector if a previous passenger has triggered the alarm of the metal detector. In such situations, the previous passenger will be asked to check pockets for metal objects, will deposit those objects in a tray for passage through the X-ray apparatus and then will be asked to walk through the metal detector again. This process can be repeated more than once and eventually that previous passenger may be subjected to a more direct screening by a handheld metal detector. During this time, the luggage of passengers who are delayed continues through the X-ray scanning apparatus. In many instances, a person's carry-on luggage will have been waiting at the outlet end of the X-ray scanning apparatus by the time the person has passed through the metal detector. In other situations, the passenger will have proceeded through the metal detector and must wait while the security personnel checks and rechecks images produced by the X-ray screening of a previous passenger's luggage. Thus, the movement of carry-on luggage and passengers through the security checkpoint occurs at approximately the same time, but entirely independent of one another. Furthermore, the checking of carry-on luggage by the X-ray apparatus and the security personnel who monitor the X-ray screen is carried out entirely independently of observations made by the ticket agent at the check-in counter.
Some carry-on luggage is subject to screening for explosives, narcotics or other contraband. These devices typically operate by wiping a soft flexible porous trap over the carry-on luggage. The trap is formed from a material that will entrain microscopic particles of interest. The trap then is placed in a detector that checks for the presence of explosives or narcotics. An apparatus of this type is disclosed, for example, in U.S. Pat. No. 5,491,337. The screening of luggage in this manner may be carried out randomly or based on observations by security personnel at the security checkpoint. Additionally, confusion at the outlet end of the X-ray screening apparatus often results in missed opportunities for more detailed screening.
In view of the above, it is an object of the subject invention to provide apparatus for a more coordinated screening of passengers and luggage at security checkpoints, and to improve security, reduce the average inspection time and reduce the cost of manning the checkpoint.


Circuits and methods for modulators that receive symbols, and provide I (incident, or in-phase) and Q (quadrature) component values from a look-up table for subsequent filtering and digital-to-analog conversion. The I and Q component values depend on frequency correction and time index signals such that operating frequency differences between a handset and base station are compensated for, and the transmitted symbols are continuously phase shifted by 3π/8 radians.

This application relates to modulators for wireless transmitters, and more particularly to modulators for wireless transmitters consistent with the EDGE standard.
Wireless handsets or terminals communicate with each other through the air using base stations or cell antennas as intermediaries. Each handset or terminal includes a transmitter and a receiver. Transmitters receive binary data and convert this data to symbols, forming a signal that is transmitted. Receivers receive the transmitted symbols, and convert them to binary data. The base stations are capable of receiving and transmitting several signals simultaneously.
The frequency at which a handset transmits symbols is determined by a clock signal that is generated locally, that is, in the handset. This clock signal is typically generated using a crystal or other periodic clock source. These crystals are highly accurate, for example, they may be accurate to within a few parts per million. But a base station has its own locally generated clock source, which is, typically, extremely accurate, and does not necessarily match the frequency of the clock signal in a particular handset. Also, to reduce costs of the handsets, it is desirable to use rower costs crystals having higher tolerances, leading to larger frequency differences between a handset and a base station.
Accordingly, a frequency correction may be used to correct for differences in frequency between the handset crystal and the base station clock. A base station typically communicates with several handsets. Thus it is desirable for the frequency correction to occur at the handset—it would be very difficult for the base station to adjust to several handsets simultaneously. Instead, a frequency offset may be determined by comparing the frequency of symbols received from a base station to the handset clock signal. This frequency offset may then be used to correct the frequency of symbols transmitted from the handset to the base station.
Also, the EDGE standard provides for a 3π/8 phase shift to each transmitted symbol. This phase shift reduces zero crossings seen at the transmitter power amplifier, and the fluctuations in the output envelope are reduced.
Thus, it is desirable to have a modulator that provides frequency correction, a 3π/8 phase shift, and converts symbols to I and Q component values for transmission.


A continuous-time band-pass ΔΣ AD modulator subtracts an analog signal from a DA converter from an inputted analog signal, outputs an analog signal having a subtraction result to an AD converter via a continuous-time analog band-pass filter, outputs a digital signal from the AD converter to the DA converter, and outputs the same digital signal as a digital signal subjected to a band-pass ΔΣ AD modulation processing. The highest input frequency “fin” of the inputted analog signal is substantially set to three-fourths of a sampling frequency “fs”. The DA converter is configured to convert the inputted digital signal into the analog signal, and outputs the analog signal, which is inverted or not in response to a value of the inputted digital signal and has an amplitude of substantially zero and a gradient of substantially zero at a timing k/(2fs).

1. Field of the Invention
The present invention relates to a band-pass ΔΣ AD modulator for AD-converting a high frequency narrow-band signal with higher precision and lower power consumption which is provided in an analog front-end of a receiver such as a radio LAN or a portable telephone, and a digital radio receiver using the same band-pass ΔΣ AD modulator.
2. Description of the Prior Art
The use of a band-pass ΔΣ AD modulator has been examined for AD-converting a high frequency narrow-band signal with higher precision and lower power consumption which is provided in an analog front-end of a receiver such as a radio LAN or a portable telephone (See first to sixth non-patent documents described later, for example).
Prior art documents related to the present invention are as follows:
(1) first patent document: Japanese patent laid-open publication No. JP-2000-244323-A;
(2) second patent document: Japanese patent laid-open publication No. JP-2002-100992-A;
(3) first non-patent document: F. Munoz et al., "A 4.7 mW 89.5 dB DR CT Complex ΔΣ ADC with Built-in LPF", ISSCC Digest of Technical Papers, Vol. 47, pp. 500–501, February 2005;
(4) second non-patent document: R. Schreier et al., "A 10–300 MHz IF-digitizing IC with 90–105-d B dynamic range and 15–333-kHz band width", IEEE Journal of Solid-State Circuits, Vol. 37 No 12, pp. 1636–1644, December 2002;
(5) third non-patent document: T. Salo et al., "A Dual-Mode 80 MHz Bandpass ΔΣ Modulator for a GSM/WCDMA IF-receiver", ISSCC Digest of Technical Papers, Vol. 45, pp. 218–219, February 2002;
(6) fourth non-patent document: U. V. Kack et al., "Direct RF Sampling continuous-Time Bandpass ΔΣ A/D Converter Design for 3G Wireless Applications", Proceedings of IEEE ISCA, pp. I-409–J-412, Vancouver, Canada, May 2004;
(7) fifth non-patent document: P. Fontaine et al., "A Low-Noise Low-Voltage CT ΔΣ Modulator with Digital Compensation of Excess Loop Delay", ISSCC Digest of Technical Papers, Vol. 47, pp. 498–499, February 2004;
(8) sixth non-patent document: H. San et al., "A noise-shaping algorithm of multi-bit DAC nonlinearities in complex bandpass ΔΣ AD modulators", IEICE Transactions on Fundamentals, Vol. E87-A, N. 4, pp. 792–800, April 2004;
(9) seventh non-patent document S. R. Norsworthy et al. (editors), "Delta-Sigma Data Converters,-Theory, Design and Simulation", IEEE Press, pp. 244–245, 1997;
(10) eighth non-patent document: S. Luschs et al., "Radio Frequency Digital-to-Analog Converter", IEEE Journal of Solid-State Circuits, Vol. 39, No. 9, pp. 1462–1467, September 2004; and
(11) ninth non-patent document: H. Kobayashi et al., "Sampling Jitter and Finite Aperture Time Effects in Wideband Data Acquisition Systems", IEICE Transactions on Fundamentals, Vol. E85-A, No. 2, pp. 335–346, February 2002.
Various kind of examinations have been made for realizing a software radio system according to a prior art having a minimum-analog and rich-digital circuit configuration, from which a frequency converter circuit for converting an RF signal into a baseband is eliminated so as to directly AD-convert the RF signal (See FIG. 1A). A digital radio receiver according to the prior art of FIG. 1A is constituted by including an antenna 1, a band-pass filter 2, a low-noise amplifier 3, a frequency converter unit 4 for converting an inputted signal into a baseband, a pair of low-pass ΔΣ AD modulators 5a and 5b, and a digital signal processor (DSP) 6. In all the drawings including FIG. 1A and being subsequent to FIG. 1A, an AD converter (analog-to-digital converter) will be abbreviated as an ADC, and a DA converter (digital-to-analog converter) will be abbreviated as a DAC.
Referring to FIG. 1A, conventionally, a configuration of a discrete-time circuit (FIG. 3) has been often used which utilizes a switched capacitor circuit capable of performing AD conversion with higher precision. However, recently, a configuration of a continuous-time circuit (FIG. 4) is studied which utilizes a continuous-time analog filter in the continuous-time circuit, because of the possibility of the operation at a higher rate and with lower power consumption. In this case, an influence of a clock jitter of the internal AD converter is relatively small because of noise-shaping, however, such a problem occurs that an influence of a jitter of an internal DA converter leads to deterioration in precision of the entire AD modulator.

Band-pass Δ-Σ AD modulator for AD-converting high frequency narrow-band signal with higher precision and lower power consumption

Semiconductor Technology Academic Research Center