The present invention provides a method and system for quickly deallocating packet traffic channels. According to exemplary embodiments of the present invention, the capability of performing point-to-multipoint communications is provided on the PTCH by defining a multicast address that all mobiles read. Through the use of a multicast address, a plurality of mobile stations can simultaneously be notified of the termination of PTCH services. As a result, the network can reallocate PTCH resources in a minimum amount of time.

The present invention relates generally to radiocommunication systems and, more particularly, to techniques and structures for reassigning packet traffic channels in a radiocommunication system.
In North America, digital communication and multiple access techniques such as TDMA are currently provided by a digital cellular radiotelephone system called the digital advanced mobile phone service (D-AMPS), some of the characteristics of which are specified in the interim standard TIA/EIA/IS-54, xe2x80x9cDual-Mode Mobile Station-Base Station Compatibility Standardxe2x80x9d, published by the Telecommunications Industry Association and Electronic Industries Association (TIA/EIA), which is expressly incorporated herein by reference. Because of a large existing consumer base of equipment operating only in the analog domain with frequency-division multiple access (FDMA), TIA/EIA/IS-54 is a dual-mode (analog and digital) standard, providing for analog compatibility together with digital communication capability. For example, the TIA/EIA/IS-54 standard provides for both FDMA analog voice channels (AVC) and TDMA digital traffic channels (DTC). The AVCs and DTCs are implemented by frequency modulating radio carrier signals, which have frequencies near 800 megahertz (MHz) such that each radio channel has a spectral width of 30 kilohertz (KHz).
In a TDMA cellular radiotelephone system, each radio channel is divided into a series of time slots, each of which contains a burst of information from a data source, e.g., a digitally encoded portion of a voice conversation. The time slots are grouped into successive TDMA frames having a predetermined duration. The number of time slots in each TDMA frame is related to the number of different users that can simultaneously share the radio channel. If each slot in a TDMA frame is assigned to a different user, the duration of a TDMA frame is the minimum amount of time between successive time slots assigned to the same user.
The successive time slots assigned to the same user, which are usually not consecutive time slots on the radio carrier, constitute the user""s digital traffic channel, which may be considered a logical channel assigned to the user. As described in more detail below, digital control channels (DCCHs) can also be provided for communicating control signals, and such a DCCH is a logical channel formed by a succession of usually non-consecutive time slots on the radio carrier.
In only one of many possible embodiments of a TDMA system as described above, the TIA/EIA/IS-54 standard provided that each TDMA frame consists of six consecutive time slots and has a duration of 40 milliseconds (msec). Thus, each radio channel can carry from three to six DTCs (e.g., three to six telephone conversations), depending on the source rates of the speech coder/decoders (codecs) used to digitally encode the conversations. Such speech codecs can operate at either full-rate or half-rate. A full-rate DTC requires twice as many time slots in a given time period as a half-rate DTC, and in TIA/EIA/IS-54, each full-rate DTC uses two slots of each TDMA frame, i.e., the first and fourth, second and fifth, or third and sixth of a TDMA frame""s six slots. Each half-rate DTC uses one time slot of each TDMA frame. During each DTC time slot, 324 bits are transmitted, of which the major portion, 260 bits, is due to the speech output of the codec, including bits due to error correction coding of the speech output, and the remaining bits are used for guard times and overhead signalling for purposes such as synchronization.
It can be seen that the TDMA cellular system operates in a buffer-and-burst, or discontinuous-transmission, mode: each mobile station transmits (and receives) only during its assigned time slots. At full rate, for example, a mobile station might transmit during slot 1, receive during slot 2, idle during slot 3, transmit during slot 4, receive during slot 5, and idle during slot 6, and then repeat the cycle during succeeding TDMA frames. Therefore, the mobile station, which may be battery-powered, can be switched off, or sleep, to save power during the time slots when it is neither transmitting nor receiving.
In addition to voice or traffic channels, cellular radio communication systems also provide paging/access, or control, channels for carrying call-setup messages between base stations and mobile stations. According to TIA/EIA/IS-54, for example, there are twenty-one dedicated analog control channels (ACCs), which have predetermined fixed frequencies for transmission and reception located near 800 MHz. Since these ACCs are always found at the same frequencies, they can be readily located and monitored by the mobile stations.
For example, when in an idle state (i.e., switched on but not making or receiving a call), a mobile station in a TIA/EIA/IS-54 system tunes to and then regularly monitors the strongest control channel (generally, the control channel of the cell in which the mobile station is located at that moment) and may receive or initiate a call through the corresponding base station. When moving between cells while in the idle state, the mobile station will eventually xe2x80x9closexe2x80x9d radio connection on the control channel of the xe2x80x9coldxe2x80x9d cell and tune to the control channel of the xe2x80x9cnewxe2x80x9d cell. The initial tuning and subsequent re-tuning to control channels are both accomplished automatically by scanning all the available control channels at their known frequencies to find the xe2x80x9cbestxe2x80x9d control channel. When a control channel with good reception quality is found, the mobile station remains tuned to this channel until the quality deteriorates again. In this way, mobile stations stay xe2x80x9cin touchxe2x80x9d with the system.
While in the idle state, a mobile station must monitor the control channel for paging messages addressed to it. For example, when an ordinary telephone (land-line) subscriber calls a mobile subscriber, the call is directed from the public switched telephone network (PSTN) to a mobile switching center (MSC) that analyzes the dialed number. If the dialed number is validated, the MSC requests some or all of a number of radio base stations to page the called mobile station by transmitting over their respective control channels paging messages that contain the mobile identification number (MIN) of the called mobile station. Each idle mobile station receiving a paging message compares the received MIN with its own stored MIN. The mobile station with the matching stored MIN transmits a page response over the particular control channel to the base station, which forwards the page response to the MSC.
Upon receiving the page response, the MSC selects an AVC or a DTC available to the base station that received the page response, switches on a corresponding radio transceiver in that base station, and causes that base station to send a message via the control channel to the called mobile station that instructs the called mobile station to tune to the selected voice or traffic channel. A through-connection for the call is established once the mobile station has tuned to the selected AVC or DTC.
The performance of the system having ACCs that is specified by TIA/EIA/IS-54 has been improved in a system having digital control channels (DCCHs) that is specified in TIA/EIA/IS-136, which is expressly incorporated by reference herein. One example of such a system having DCCHs with new formats and processes is described in U.S. patent application Ser. No. 07/956,640 entitled xe2x80x9cDigital Control Channelxe2x80x9d, which was filed on Oct. 5, 1992, and which is incorporated in this application by reference. Using such DCCHs, each TIA/EIA/IS-54 radio channel can carry DTCs only, DCCHs only, or a mixture of both DTCs and DCCHs. Within the TIA/EIA/IS-136 framework, each radio carrier frequency can have up to three full-rate DTCs/DCCHs, or six half-rate DTCs/DCCHs, or any combination in between, for example, one full-rate and four half-rate DTCs/DCCHs.
In general, however, the transmission rate of the DCCH need not coincide with the half-rate and full-rate specified in TIA/EIA/IS-54, and the length of the DCCH slots may not be uniform and may not coincide with the length of the DTC slots. The DCCH may be defined on an TIA/EIA/IS-54 radio channel and may consist, for example, of every n-th slot in the stream of consecutive TDMA slots. In this case, the length of each DCCH slot may or may not be equal to 6.67 msec, which is the length of a DTC slot according to TIA/EIA/IS-54. Alternatively (and without limitation on other possible alternatives), these DCCH slots may be defined in other ways known to one skilled in the art.
In cellular telephone systems, an air link protocol is required in order to allow a mobile station to communicate with the base stations and MSC. The communications link protocol is used to initiate and to receive cellular telephone calls. As described in U.S. patent application Ser. No. 08/477,574 entitled xe2x80x9cLayer 2 Protocol for the Random Access Channel and the Access Response Channel,xe2x80x9d which was filed on Jun. 7, 1995, and which is incorporated in this application by reference, the communications link protocol is commonly referred to within the communications industry as a Layer 2 protocol, and its functionality includes the delimiting, or framing, of Layer 3 messages. These Layer 3 messages may be sent between communicating Layer 3 peer entities residing within mobile stations and cellular switching systems. The physical layer (Layer 1) defines the parameters of the physical communications channel, e.g., radio frequency spacing, modulation characteristics, etc. Layer 2 defines the techniques necessary for the accurate transmission of information within the constraints of the physical channel, e.g., error correction and detection, etc. Layer 3 defines the procedures for reception and processing of information transmitted over the physical channel.
Communications between mobile stations and the cellular switching system (the base stations and the MSC) can be described in general with reference to FIGS. 1 and 2. FIG. 1 schematically illustrates pluralities of Layer 3 messages 11, Layer 2 frames 13, and Layer 1 channel bursts, or time slots, 15. In FIG. 1, each group of channel bursts corresponding to each Layer 3 message may constitute a logical channel, and as described above, the channel bursts for a given Layer 3 message would usually not be consecutive slots on an TIA/EIA/136 carrier. On the other hand, the channel bursts could be consecutive; as soon as one time slot ends, the next time slot could begin.
Each Layer 1 channel burst 15 contains a complete Layer 2 frame as well as other information such as, for example, error correction information and other overhead information used for Layer 1 operation. Each Layer 2 frame contains at least a portion of a Layer 3 message as well as overhead information used for Layer 2 operation. Although not indicated in FIG. 1, each Layer 3 message would include various information elements that can be considered the payload of the message, a header portion for identifying the respective message""s type, and possibly padding.
Each Layer 1 burst and each Layer 2 frame is divided into a plurality of different fields. In particular, a limited-length DATA field in each Layer 2 frame contains the Layer 3 message 11. Since Layer 3 messages have variable lengths depending upon the amount of information contained in the Layer 3 message, a plurality of Layer 2 frames may be needed for transmission of a single Layer 3 message. As a result, a plurality of Layer 1 channel bursts may also be needed to transmit the entire Layer 3 message as there is a one-to-one correspondence between channel bursts and Layer 2 frames.
As noted above, when more than one channel burst is required to send a Layer 3 message, the several bursts are not usually consecutive bursts on the radio channel. Moreover, the several bursts are not even usually successive bursts devoted to the particular logical channel used for carrying the Layer 3 message. Since time is required to receive, process, and react to each received burst, the bursts required for transmission of a Layer 3 message are usually sent in a staggered format, as schematically illustrated in FIG. 2(a) and as described above in connection with the TIA/EIA/IS-136 standard.
FIG. 2(a) shows a general example of a forward (or downlink) DCCH configured as a succession of time slots 1, 2, . . . , N, . . . included in the consecutive time slots 1, 2, . . . sent on a carrier frequency. These DCCH slots may be defined on a radio channel such as that specified by TIA/EIA/IS-136, and may consist, as seen in FIG. 2(a) for example, of every n-th slot in a series of consecutive slots. Each DCCH slot has a duration that may or may not be 6.67 msec, which is the length of a DTC slot according to the TIA/EIA/IS-136 standard.
As shown in FIG. 2(a), the DCCH slots may be organized into superframes (SF), and each superframe includes a number of logical channels that carry different kinds of information. One or more DCCH slots may be allocated to each logical channel in the superframe. The exemplary downlink superframe in FIG. 2(a) includes three logical channels: a broadcast control channel (BCCH) including six successive slots for overhead messages; a paging channel (PCH) including one slot for paging messages; and an access response channel (ARCH) including one slot for channel assignment and other messages. The remaining time slots in the exemplary superframe of FIG. 2 may be dedicated to other logical channels, such as additional paging channels PCH or other channels. Since the number of mobile stations is usually much greater than the number of slots in the superframe, each paging slot is used for paging several mobile stations that share some unique characteristic, e.g., the last digit of the MIN.
FIG. 2(b) illustrates an exemplary information format for the slots of a forward DCCH. FIG. 2(b) indicates the number of bits in each field above that field. The bits sent in the SYNC information are used in a conventional way to help ensure accurate reception of the coded superframe phase (CSFP) and DATA fields. The SYNC information carries a predetermined bit pattern used by the base stations to find the start of the slot. The shared channel feedback (SCF) information is used to control a random access channel (RACH), which is used by the mobile to request access to the system. The CSFP information conveys a coded superframe phase value that enables the mobile stations to find the start of each superframe. This is just one example for the information format in the slots of the forward DCCH.
For purposes of efficient sleep mode operation and fast cell selection, the BCCH may be divided into a number of sub-channels. U.S. patent application Ser. No. 07/956,640 discloses a BCCH structure that allows the mobile station to read a minimum amount of information when it is switched on (when it locks onto a DCCH) before being able to access the system (place or receive a call). After being switched on, an idle mobile station needs to regularly monitor only its assigned PCH slots (usually one in each superframe); the mobile can sleep during other slots. The ratio of the mobile""s time spent reading paging messages and its time spent asleep is controllable and represents a tradeoff between call-set-up delay and power consumption.
Since each TDMA time slot has a certain fixed information carrying capacity, each burst typically carries only a portion of a Layer 3 message as noted above. In the uplink direction, multiple mobile stations attempt to communicate with the system on a contention basis, while multiple mobile stations listen for Layer 3 messages sent from the system in the downlink direction. In known systems, any given Layer 3 message is carried using as many TDMA channel bursts as required to send the entire Layer 3 message.
Digital control and traffic channels are desirable for these and other reasons described in U.S. patent application Ser. No. 08/147,254, entitled xe2x80x9cA Method for Communicating in a Wireless Communication Systemxe2x80x9d, which was filed on Nov. 1, 1993, and which is incorporated herein by reference. For example, they support longer sleep periods for the mobile units, which results in longer battery life.
Digital traffic channels and digital control channels have expanded functionality for optimizing system capacity and supporting hierarchical cell structures, i.e., structures of macrocells, microcells, picocells, etc. The term xe2x80x9cmacrocelxe2x80x9d generally refers to a cell having a size comparable to the sizes of cells in a conventional cellular telephone system (e.g., a radius of at least about 1 kilometer), and the terms xe2x80x9cmicrocellxe2x80x9d and xe2x80x9cpicocellxe2x80x9d generally refer to progressively smaller cells. For example, a microcell might cover a public indoor or outdoor area, e.g., a convention center or a busy street, and a picocell might cover an office corridor or a floor of a high-rise building. From a radio coverage perspective, macrocells, microcells, and picocells may be distinct from one another or may overlap one another to handle different traffic patterns or radio environments.
The systems specified by the TIA/EIA/IS-54 and TIA/EIA/IS-136 standards are circuit-switched technology, which is a type of xe2x80x9cconnection-orientedxe2x80x9d communication that establishes a physical call connection and maintains that connection for as long as the communicating end-systems have data to exchange. The direct connection of a circuit switch serves as an open pipeline, permitting the end-systems to use the circuit for whatever they deem appropriate. While circuit-switched data communication may be well suited to constant-bandwidth applications, it is relatively inefficient for low-bandwidth and xe2x80x9cburstyxe2x80x9d applications.
Packet-switched technology, which may be connection-oriented (e.g., X.25) or xe2x80x9cconnectionlessxe2x80x9d (e.g., the Internet Protocol, xe2x80x9cIPxe2x80x9d), does not require the set-up and tear-down of a physical connection, which is in marked contrast to circuit-switched technology. This reduces the data latency and increases the efficiency of a channel in handling relatively short, bursty, or interactive transactions. A connectionless packet-switched network distributes the routing functions to multiple routing sites, thereby avoiding possible traffic bottlenecks that could occur when using a central switching hub. Data is xe2x80x9cpacketizedxe2x80x9d with the appropriate end-system addressing and then transmitted in independent units along the data path. Intermediate systems, sometimes called xe2x80x9croutersxe2x80x9d, stationed between the communicating end-systems make decisions about the most appropriate route to take on a per packet basis. Routing decisions are based on a number of characteristics, including: least-cost route or cost metric; capacity of the link; number of packets waiting for transmission; security requirements for the link; and intermediate system (node) operational status.
Packet transmission along a route that takes into consideration path metrics, as opposed to a single circuit set up, offers application and communications flexibility. It is also how most standard local area networks (LANs) and wide area networks (WANs) have evolved in the corporate environment. Packet switching is appropriate for data communications because many of the applications and devices used, such as keyboard terminals, are interactive and transmit data in bursts. Instead of a channel being idle while a user inputs more data into the terminal or pauses to think about a problem, packet switching interleaves multiple transmissions from several terminals onto the channel.
Packet data provides more network robustness due to path independence and the routers"" ability to select alternative paths in the event of network node failure. Packet switching, therefore, allows for more efficient use of the network lines. Packet technology offers the option of billing the end user based on amount of data transmitted instead of connection time. If the end user""s application has been designed to make efficient use of the air link, then the number of packets transmitted will be minimal. If each individual user""s traffic is held to a minimum, then the service provider has effectively increased network capacity.
Packet networks are usually designed and based on industry-wide data standards such as the open system interface (OSI) model or the TCP/IP protocol stack. These standards have been developed, whether formally or de facto, for many years, and the applications that use these protocols are readily available. The main objective of standards-based networks is to achieve interconnectivity with other networks. The Internet is today""s most obvious example of such a standards-based network pursuit of this goal.
Packet networks, like the Internet or a corporate LAN, are integral parts of today""s business and communications environments. As mobile computing becomes pervasive in these environments, wireless service providers such as those using TIA/EIA/IS-136 are best positioned to provide access to these networks. Nevertheless, the data services provided by or proposed for cellular systems are generally based on the circuit-switched mode of operation, using a dedicated radio channel for each active mobile user.
FIG. 3 shows representative architecture used for communicating across an air link that comprises the protocols which provide connectivity between a mobile end system (M-ES), a mobile data base station (MDBS), and a mobile data intermediate system (MD-IS). An exemplary description of the elements in FIG. 3 and a recommended approach for each element when considering alternative RF technologies follows.
The Internet Protocol/Connectionless Network Protocol (IP/CLNP) are network protocols that are connectionless and widely supported throughout the traditional data network community. These protocols are independent of the physical layer and preferably are not modified as the RF technologies change.
The Security Management Protocol (SMP) provides security services across the air link interface. The services furnished include data link confidentiality, M-ES authentication, key management, access control, and algorithm upgradability/replacement. The SMP should remain unchanged when implementing alternative RF technologies.
The Radio Resource Management Protocol (RRMP) provides management and control over the mobile unit""s use of the RF resources. The RRMP and its associated procedures are specific to the AMPS RF infrastructure and require change based on the RF technology implemented.
The Mobile Network Registration Protocol (MNRP) is used in tandem with a Mobile Network Location Protocol (MNLP) to allow proper registration and authentication of the mobile end system. The MNRP should be unchanged when using alternative RF technologies.
The Mobile Data Link Protocol (MDLP) provides efficient data transfer between the MD-IS and the M-ES. The MDLP supports efficient mobile system movement, mobile system power conservation, RF channel resources sharing, and efficient error recovery. The MDLP should be unchanged when using alternative RF technologies.
The Medium Access Control (MAC) protocol and associated procedures control the methodology M-ESs use to manage shared access to the RF channel. This protocol and its functionality must be supplied by alternative RF technologies.
Modulation and encoding schemes are used at the physical layer. These schemes are specific to the RF technology employed, and therefore should be replaced with schemes appropriate for the alternative RF technology. The adoption of alternative RF technologies can be implemented with a minimum amount of change to the CDPD system architecture. The required changes are limited to the radio resource management protocol, the MAC, and physical layers; all other network services and support services remain unchanged.
A few exceptions to data services for cellular systems based on the circuit-switched mode of operation are described in the following documents, which include the packet data concepts.
U.S. Pat. No. 4,887,265 and xe2x80x9cPacket Switching in Digital Cellular Systemsxe2x80x9d, Proc. 38th IEEE Vehicular Technology Conf., pp. 414-418 (June 1988) describe a cellular system providing shared packet data radio channels, each one capable of accommodating multiple data calls. A mobile station requesting packet data service is assigned to a particular packet data channel using essentially regular cellular signalling. The system may include packet access points (PAPS) for interfacing with packet data networks. Each packet data radio channel is connected to one particular PAP and is thus capable of multiplexing data calls associated with that PAP. Handovers are initiated by the system in a manner that is largely similar to the handover used in the same system for voice calls. A new type of handover is added for those situations when the capacity of a packet channel is insufficient.
These documents are data-call oriented and based on using system-initiated handover in a similar way as for regular voice calls. Applying these principles for providing general purpose packet data services in a TDMA cellular system would result in spectrum inefficiency and performance disadvantages.
U.S. Pat. No. 4,916,691 describes a new packet mode cellular radio system architecture and a new procedure for routing (voice and/or data) packets to a mobile station. Base stations, public switches via trunk interface units, and a cellular control unit are linked together via a WAN. The routing procedure is based on mobile station-initiated handovers and on adding to the header of any packet transmitted from a mobile station (during a call) an identifier of the base station through which the packet passes. In case of an extended period of time between subsequent user information packets from a mobile station, the mobile station may transmit extra control packets for the purpose of conveying cell location information.
The cellular control unit is primarily involved at call establishment, when it assigns to the call a call control number. It then notifies the mobile station of the call control number and the trunk interface unit of the call control number and the identifier of the initial base station. During a call, packets are then routed directly between the trunk interface unit and the currently serving base station.
The system described in U.S. Pat. No. 4,916,691 is not directly related to the specific problems of providing packet data services in TDMA cellular systems.
xe2x80x9cPacket Radio in GSMxe2x80x9d, European Telecommunications Standards Institute (ETSI) T Doc SMG 4 58/93 (Feb. 12, 1993) and xe2x80x9cA General Packet Radio Service Proposed for GSMxe2x80x9d presented during a seminar entitled xe2x80x9cGSM in a Future Competitive Environmentxe2x80x9d, Helsinki, Finland (Oct. 13, 1993) outline a possible packet access protocol for voice and data in GSM. These documents directly relate to TDMA cellular systems, i.e., GSM, and although they outline a possible organization of an optimized shared packet data channel, they do not deal with the aspects of integrating packet data channels in a total system solution.
xe2x80x9cPacket Data over GSM Networkxe2x80x9d, T Doc SMG 1 238/93, ETSI (Sep. 28, 1993) describes a concept of providing packet data services in GSM based on first using regular GSM signalling and authentication to establish a virtual channel between a packet mobile station and an xe2x80x9cagentxe2x80x9d handling access to packet data services. With regular signalling modified for fast channel setup and release, regular traffic channels are then used for packet transfer. This document directly relates to TDMA cellular systems, but since the concept is based on using a xe2x80x9cfast switchingxe2x80x9d version of existing GSM traffic channels, it has disadvantages in terms of spectrum efficiency and packet transfer delays (especially for short messages) compared to a concept based on optimized shared packet data channels.
New standards are currently being settled for integrated voice and packet data services in ANSI-136 systems. A forthcoming version of the standard will provide the ability to create an effective radio resource utilization for the voice and packet data services supplied. One such attempt to provide an effective radio resource for voice and packet data services is described in U.S. Pat. No. 5,790,551 to Chan. A dynamic channel assignment technique is disclosed therein where the network provides to a mobile user, in response to a request from the mobile for assignment of a channel on which to transmit data, a particular channel and particular time slots on which the mobile may transmit. As such, no channels are specifically dedicated to data transmissions; rather, the network determines a channel that is free for a specific time period and assigns it to a specific mobile for data transmission. This document does not, however, disclose how to efficiently deallocate a packet traffic channel which is to be used for other services.
The new ANSI-136 standards will likely support two types of channels for packet data transmissions: a packet control channel (PCCH) and a packet traffic channel (PTCH). The PCCH may be either a point-to-point or point-to-multipoint channel. It is this channel on which a mobile station camps (i.e., where the mobile reads broadcast and paging information and where the mobile has random access and reserved access opportunities). The PTCH, on the other hand, is a point-to-point, reserved access only, channel. As will be appreciated by those skilled in the art, a physical channel can provide either packet data services or voice services or can simultaneously provide both packet data and voice services. Neither broadcast nor paging capabilities are included in the PTCH concept.
Upon activation, a mobile station selects a PCCH on which to camp. If multiple PCCHs exist in a cell, then the mobile station selects one depending, for example, on the mobile station""s identification. For instance, if the least significant bit of the mobile station""s identification is 00, the mobile station will choose one PCCH; if the least significant bit is 01, it will choose another PCCH, etc. By selecting a PCCH in the above-described manner, paging traffic is spread out over the available PCCHs.
Upon a contention-based access from the mobile station or upon receiving mobile termination data from the network, the network may direct the mobile station to tune to a specific PTCH for its packet transmission. Once on a PTCH, the network (e.g., the base station) schedules resources for the specific mobile. When the mobile has completed the transaction and a configurable inactivity timer in the mobile station expires (generally after 1 second of inactivity), the mobile station returns to camp on the original PCCH.
Once a PTCH has been assigned for packet data communications, certain situations may arise in which the PTCH is to be reassigned for voice communications. For example, if a cell has three channels which have been allotted for packet data or voice communications and no voice activity is occurring, then all three channels can be assigned for packet data communications. Thereafter, if a voice communication is requested, the resource manager notifies the packet data manager that one full channel is to be provided for the voice communications. In such an event, the packet data manager deallocates one channel from packet data communications and reallocates the channel for voice communications. A delay of 100 ms is acceptable to switch a traffic channel over from providing packet data services to providing voice services; therefore, the amount of time for deallocating an active PTCH should be minimized.
Another situation arises when, for example, the radio quality of a PTCH, which has been assigned to packet data communications, decreases below an acceptable level. In such an event, the packet data manager may decide to switch those mobile stations which are active on that PTCH to another PTCH in order to maintain end user required quality of service.
Due to the point-to-point communication aspect of the PTCH, problems arise in how best to deallocate the PTCH (i.e., how to notify the mobile stations which are currently using the PTCH that the PTCH services are being removed) so as to minimize the amount of delay to the voice users and active packet data users. One method of providing this notification is to directly send a redirect order to one mobile station at a time. When many active mobiles exist on a PTCH, the time to force all mobiles to leave the channel will be long. Another approach would be to simply turn off the packet traffic channel without informing the active mobile stations. In such an event, the mobile stations, upon receiving no more data from the network and upon the expiration of the one second activity timer, will fall back to the PCCH on which they were camped. Such a deallocation process, however, increases the time for the packet data end users to regain access to the network.
Therefore, there exists the need to be able to quickly and efficiently deallocate data packet services based on an end users"" current demand or other criteria.
The present invention overcomes the above-identified deficiencies in the art by providing a method and system for quickly deallocating packet traffic channels. According to exemplary embodiments of the present invention, the capability of performing point-to-multipoint communications is provided on the PTCH by defining a multicast address that all mobiles read. Through the use of a multicast address, a plurality of mobile stations can simultaneously be notified of the termination of PTCH services. As a result, the network can reallocate PTCH resources in a minimum amount of time.


A semiconductor integrated circuit includes an output circuit driven by a power voltage across a first and a second node. A control circuit is driven by the power voltage to control output a digital signal at a pad terminal, a logic value of the signal being set by a core circuit connected to the output circuit. The digital signal causes a voltage at the first node to be high and a voltage at the second node to low when a predetermined power voltage higher than a withstanding voltage of the output circuit is applied across the first and second nodes. The control circuit controls voltages across terminals of switching elements in the output circuit to be less than their withstanding voltages and to prevent current flowing from the pad terminal to the output circuit when the first power node is in a high impedance state.

When a voltage is applied to a signal pin of an IC (Integrated Circuit) when a power source of the IC is in a cut off state, a large amount of current may flow into the IC. Therefore, the IC may be damaged or degraded in reliability. A structure for avoiding this problem is called a "Hot Swap" (hot swap) design or may be referred to as a "hot swappable" component.
A withstanding voltage of a device element, such as a MOSFET, mounted in an LSI (Large-Scale Integration) product of a state-of-the-art design process (e.g., the smallest semiconductor features) will often be lowered to 1.8 V, for example, to enable a higher speed operation and lower power consumption. However, there are mounted components for some LSI products that still are using older generation design processes that might be mounted on the same board with components using the state-of-the-art design processes. In interfacing between the different generation LSI products, data is generally exchanged at a standard signal level (for example, 3.3 V) used by the older generation LSI components. From such a circumstance, the LSI product using the state-of-the-art process employs a circuit design that requires the element to be able handle a signal at a voltage level equal to or greater than the withstanding voltage level of the element. Such a circuit design is called a "tolerant design."
When a tolerant design is implemented, the overall operation of the circuit typically becomes slower in general. In addition, there is no proposed integrated circuit design in which a tolerant design is implemented in a hot swap design of an IC.


At least some example embodiments disclose a method and device for displaying a background image that may change an arrangement of an object based on image information associated with the background image and change a visual effect with respect to an adjacent region of the object.

1. Field
At least some example embodiments of the following description relate to a method and device for displaying a background image.
2. Description of the Related Art
Recent electronic devices may provide an option to display a background image. For example, a user may select a desired image and may use the desired image as a background image to be displayed in the background of a portable electronic device.
The image used as the background image may be an image that a user photographs through a camera attached to an electronic device, or may be an externally acquired image that the user stores on the electronic device. For example, the electronic device may provide a function through which the user freely changes background images using existing images or images photographed by the user. When the user uses the photographed images, many electronic devices may provide a function to select a specific image and a specific region in the image to be designated as a background image.
Also, the electronic device may display objects, such as an icon and a widget, on a background image. Here, a region that the user desires to reveal in the photographed image may be obscured by the icon or the widget. Thus, the user may relocate the objects randomly with respect to the background image.

Method and device for displaying background image


The present invention pertains to an optical shutter comprising a photon-absorbing layer and a surface layer in a transparent state on at least one side of the photon-absorbing layer, wherein the optical shutter is characterized by the absorption of photons to change the photon-absorbing layer to an opaque state and to change the surface layer to a reflective state. The optical shutter is reversibly imageable between these transparent and reflective states. The optical shutter may comprise a metallized layer on at least one side of the photon-absorbing layer. Preferably, the optical shutter comprises an organic free radical compound, such as a salt of an aminium radical cation, in the photon-absorbing layer. Also provided are optical switch devices and optical buffers comprising such optical shutters and methods of switching an optical signal utilizing such optical shutters and switch devices.

The present invention relates generally to the field of optical shutters and switches, and particularly, pertains to optical shutters and switches which operate in the near-infrared and/or visible wavelength regions. More specifically, this invention pertains to optical shutters and switches comprising a reversible transparent-to-reflective optical shutter. This invention also pertains to methods of switching an optical signal from one input path to a selected one of a plurality of different output paths by utilizing the optical sutters and switches of this invention.
Throughout this application, various publications, patents, and published patent applications are referred to by an identifying citation. The disclosures of the publications, patents, and published patent specifications referenced in this application are hereby incorporated by reference into the present disclosure to more fully describe the state of the art to which this invention pertains.
As the quantity and speed of data communications over fiber optics systems rapidly increases due to the growing demand from Internet usage and other communications, improved all-optical switching systems are of increased interest to overcome the high cost and slow switching speeds of conventional switches. These conventional switches include, for example, various mechanical switches, electro-optic switches, and thermo-optic switches, such as, for example, described in U.S. Pat. Nos. 5,732,168 and 5,828,799, both to Donald. In particular, the increased complexity and cost of switching systems which involve switching from an optical signal to an electrical signal and then back to an optical signal have increased the level of interest in all-optical switches.
An all-optical switch provides switching of an optical signal from one input path to a selected one of a plurality of different output paths without any intermediate conversion of the optical signal to an electrical signal. This is typically accomplished by applying an electrical signal to a switchable element to cause the optical signal to be selectively switched. These electro-optic switches are responsive to the electrical signal to selectively switch the light of the optical signal from the input path to the selected one of the output paths.
A variety of approaches are known for making all-optical or hybrid optical switches, such as, for example, described in U.S. Pat. Nos. 5,905,587 to Maeno, et al.; 5,923,798 to Aksyuk, et al.; 5,970,185 to Baker, et al.; 5,841,912 to Mueller-Fiedl al.; 5,091,984 to Kobayashi, et al.; 5,406,407 to Wolff; 5,740,287 to Scalora, et al.; 5,960,133 to Tomlinson; U.S. Pat. No. 5,539,100 to Wasielewski et al.; and 5,943,453 to Hodgson.
The need for improved optical switches is increased by the use of wavelength multiplexing which converts the optical signal in the optical fiber into, for example, 16 signals at 16 different wavelengths in a near-infrared range of about 1540 to 1560 nm, as, for example, described in Bell Labs Technical Journal, January-March 1999, pages 207 to 229, and references therein, by Giles et al.; and in U.S. Pat. No. 5,959,749 to Danagher et al. The primary function of the optical switch is to add and/or drop optical signals from the multiple wavelengths traveling through the optical fiber. It would be highly desirable to have arrays of optical switches to handle the optical signals from multiple wavelengths per optical fiber and from multiple optical fibers, such as up to 100xc3x97100 or greater optical switch arrays. Also, it would be highly desirable if the response time for the optical switch is ultrafast, such as 1 nanosecond or less.
It would be advantageous if an all-optical switching system were available which avoided the complexity and cost of hybrid electro-optic and other switching systems while increasing the speed of the switching times from the millisecond range to the nanosecond or picosecond ranges.
One aspect of the present invention pertains to an optical shutter comprising an organic free radical compound in which the free radical compound is characterized by forming an oxidized or reduced product having a change in absorption in a near-infrared wavelength region as a result of a photo-induced electron transfer reaction of the free radical compound, wherein the change in absorption is reversible. In one embodiment, the reversible change in absorption is induced by heat. In one embodiment, the reversible change in absorption is induced by radiation selected from the group consisting of ultraviolet radiation, visible radiation, and infrared radiation; and, preferably, the reversible change in absorption is further induced by the presence of oxygen.
In one embodiment of the optical shutter of this invention, the optical shutter further comprises a metallized layer on at least one side of a photon-absorbing layer comprising the free radical compound of the optical shutter. In one embodiment, the metallized layer comprises aluminum.
Another aspect of the present invention pertains to an optical shutter comprising an organic free radical compound, preferably a radical cation compound or a radical anion compound, in which the free radical compound is characterized by forming an oxidized or a reduced product having a change in absorption in a visible and/or a near-infrared region as a result of a photo-induced electron transfer reaction of the free radical compound, wherein the change in absorption is reversible. In one embodiment, the optical shutter is utilized in an optical switch device for a fiber optics communications channel.
Still another aspect of this invention pertains to an optical shutter imageable by photons and having a first state of a low absorption and low reflection at a wavelength and a second state of a high absorption and high reflection at the wavelength, which shutter comprises a photon-absorbing layer, wherein the photon-absorbing layer comprises an organic free radical compound, as described herein, and the photon-absorbing layer is characterized by absorption of the photons by the free radical compound to form a reaction product having a change in absorption at the wavelength and by a reverse reaction of the reaction product to regenerate the free radical compound; and wherein the shutter is characterized by being reversibly imageable between the first and second states. The unique properties of the optical shutter of the present invention may be utilized to prepare a wide variety of extremely compact, picosecond speed optical devices including, but not limited to, optical switches in various arrays comprising one or more of the optical shutters.
Another aspect of the present invention relates to an optical shutter having a first state of transparency and of a low reflectivity at a range of wavelengths and a second state of opacity and of a high reflectivity at a range of wavelengths, which shutter comprises a photon-absorbing layer and a surface layer on at least one side of said photon-absorbing layer, wherein the photon-absorbing layer comprises an organic free radical compound in at least one of the first and second states and is characterized by absorption of photons to form a reaction product having a change in absorption at the range of wavelengths; and wherein the shutter is characterized by being reversibly imageable between the first and second states. In one embodiment, the optical shutter comprises a metallized layer on at least one side of said of said photon-absorbing layer. In one embodiment, the metallized layer comprises aluminum. In one embodiment, the absorption of photons images the shutter from the first state to second state, and preferably, wherein the reaction product is the free radical compound. In one embodiment, the absorption of photons images the shutter from the second state to the first state, and preferably, wherein the reaction product is formed from the free radical compound. In one embodiment, absorption of photons reversibly images the shutter between the first and second states.
In one embodiment of the optical shutter of this invention, the free radical compound is a salt of an aminium radical cation. In a preferred embodiment, the free radical compound is a salt of a tetrakis[4-(dialkylamino)phenyl]-1,4-benzenediamine radical cation. In more preferred embodiment, the free radical compound is a salt of a N,N-dialkyl-Nxe2x80x2,Nxe2x80x2-bis[4-(dialkylamino)phenyl]-1,4-benzenediamine radical cation. In one embodiment, the free radical compound is a salt of an anthrasemiquinone radical anion.
In one embodiment of the optical shutter of the present invention, the wavelength range of photons imaging the shutter from the first state to the second state is different from the wavelength range of photons imaging the shutter from the second state to the first state. In one embodiment, the range of wavelengths where the change in absorption occurs is from 400 to 2000 nm.
Still another aspect of this invention pertains to an optical shutter having a first state of transparency and of low reflectivity at a range of wavelengths and a second state of opacity and of high reflectivity at the range of wavelengths, the shutter comprising a first surface layer in a transparent state, a second surface layer in a transparent state, and a photon-absorbing layer in a transparent state and interposed between the first and second surface layers, wherein the optical shutter is characterized by the absorption of photons to change at least one of the first and second surface layers to a state of high reflectivity and to change the photon-absorbing layer to a state of opacity; and wherein the shutter is characterized by being reversibly imageable between the first and second states. In one embodiment, the optical shutter is characterized by the absorption of photons to change both of the first and second surface layers to a state of high reflectivity. In one embodiment, the changes in reflectivity of the first and second surface layers occur reversibly at the same time. In one embodiment, the optical shutter comprises a metallized layer on at least one side of the photon-absorbing layer. In one embodiment, the metallized layer comprises aluminum.
In one embodiment of the optical shutter of this invention, the reversible imaging from the second state to the first state occurs with no external energy. In one embodiment, the reversible imaging from the second state to the first state is induced by heat. In one embodiment, the reversible imaging from the second state to the first state is induced by absorption of photons from one or more wavelength ranges selected from the group consisting of ultraviolet wavelength ranges, visible wavelength ranges, and infrared wavelength ranges.
Another aspect of the present invention pertains to an optical switch device comprising one or more optical input paths, two or more optical output paths, and one or more optical shutters, as described herein, the one or more shutters having a first state of transparency and of low reflectivity at a range of wavelengths and a second state of opacity and of high reflectivity at the range of wavelengths, and at least one of the one or more shutters comprises a photon-absorbing layer and a surface layer on at least one side of the photon-absorbing layer, wherein the photon-absorbing layer comprises an organic free radical compound and is characterized by absorption of photons to form a reaction product having a change in absorption at the range of wavelengths; and wherein the at least one of the one or more shutters comprising the photon-absorbing and surface layers is characterized by being reversibly imageable between the first and second states; and wherein the switch device is characterized by being capable of switching an optical signal entering the switch device from one of the one or more input paths to a selected one of the two or more output paths. In one embodiment, the switch device further comprises an optical wavelength conversion element to convert the optical signal having a first wavelength to an optical signal of a second different wavelength. In one embodiment, the optical wavelength conversion element comprises an organic free radical compound as an active material for converting the wavelength of the optical signal having the first wavelength.
Still another aspect of this invention pertains to an optical switch device comprising one or more optical input paths, two or more optical output paths, and one or more optical shutters, the one or more shutters having a first state of transparency and of low reflectivity at a range of wavelengths and a second state of opacity and of high reflectivity at the range of wavelengths, and at least one of the one or more shutters comprising a first surface layer in a transparent state, a second surface layer in a transparent state, and a photon-absorbing layer in a transparent state and interposed between the first and second surface layers, wherein the at least one of the one or more optical shutters, as described herein, that comprise the photon-absorbing and surface layers, is characterized by absorption of photons to change at least one of the first and second surface layers to a state of high reflectivity and to change the photon-absorbing layer to a state of opacity, and further is characterized by being reversibly imageable between the first and second states; and wherein the switch device is characterized by being capable of switching an optical signal entering the switch device from one of the one or more input paths to a selected one of the two or more output paths. In one embodiment, the at least one of the one or more optical shutters comprising the photon-absorbing and surface layers comprises a metallized layer on at least one side of the photon-absorbing layer. In one embodiment, the metallized layer comprises aluminum. In one embodiment, the photon-absorbing layer comprises an organic free radical compound and is characterized by an absorption of photons to form a reaction product having a change in absorption at the range of wavelengths.
In one embodiment of the optical switch device of the present invention, optical signals in the one or more input paths and the two or more output paths are bi-directional, and the switch device is characterized by the ability to switch optical signals traveling in opposite directions through the switch device. In one embodiment, the switch device comprises one or more external energy source elements to provide energy to switch the optical shutter comprising the photon-absorbing and surface layers, wherein the one or more external energy source elements are selected from the group consisting of electrical current source elements, heating source elements, ultraviolet light source elements, visible light source elements, and infrared radiation source elements. In one embodiment, the one or more external source elements are connected to an optical switch control circuit device that monitors the desired timing for providing the energy and delivers a signal to the one or more external sources of energy to provide the energy to the at least one of the one or more optical shutters comprising the photon-absorbing and surface layers.
In one embodiment of the optical switch device of this invention, the optical signal is traveling in free space in the one or more input paths and in the two or more output paths immediately prior to and immediately after the optical signal reaches the at least one of the one or more optical shutters comprising the photon-absorbing and surface layers. In one embodiment, the switch device comprises a lens in the two or more output paths to focus the optical signal. In one embodiment, the optical signal is traveling in a waveguide in the one or more input paths and in the two or more output paths immediately prior to and immediately after the optical signal reaches the at least one of the one or more optical shutters comprising the photon-absorbing and surface layers. In one embodiment, the waveguide in the two or more output paths is tapered from a larger dimension in contact to at least one of the first and second surface layers to a smaller dimension at a distance from the at least one of the first and second surface layers.
Another aspect of the present invention pertain to an optical cross-bar switch device, comprising (a) an array of optical shutters arranged in a plurality of columns and rows, each optical shutter having a first state of transparency and of low reflectivity in a range of wavelengths and a second state of opacity and of high reflectivity in the range of wavelengths, the shutter comprising a first surface layer in a transparent state, a second surface layer in a transparent state, and a photon-absorbing layer in a transparent state and interposed between the first and second layers, wherein the optical shutter is characterized by the absorption of photons to change at least one of the first and second surface layers to a state of high reflectivity and to change the photon-absorbing layer to a state of opacity; wherein the optical shutter is characterized by being reversibly imageable between the first and second states; and (b) a plurality of fiber optic ports, each fiber optic port disposed at a respective one of the columns and rows and capable of emitting and receiving a light beam so that when the light beam from a light emitting fiber optic port located at a selected one of the columns and rows is transmitted to a selected light receiving fiber optic port located at a selected remaining one of the columns and rows, the optical shutter located at an intersection formed by the selected column and row is switched to change from the non-reflective state to the reflective state to reflect the light beam from the light emitting fiber optic port to the selected light receiving fiber optic port. In one embodiment, the switch device further comprises a plurality of collimator elements, each collimator element being disposed adjacent to respective ones of each fiber optic port and between each fiber optic port and the optical shutters. In one embodiment, when the optical shutter located at the intersection formed by the selected column and row is in said second state, remaining ones of the optical shutters located in the selected column and row are in said first state. In one embodiment, a plurality of light beams from a plurality of light emitting fiber optic ports located at selected ones of the columns and rows are transmitted to a plurality of selected light receiving fiber optic ports located at selected remaining ones of the rows and columns through a plurality of optical shutters located at respective intersections formed by the selected columns and rows in the respective reflective states.
Still another aspect of this invention pertains to a method for switching an optical signal from one optical input path to a predetermined one of a plurality of different optical output paths, which method comprises the steps of (a) providing a free-space optical switch device, comprising an optical shutter disposed between an optical input path and a first and second optical output paths, the optical shutter being switchable between a transparent state in which the light from the input path is transmitted through the optical shutter to the first output path, and a reflective state in which the light from the input path is reflected from the optical shutter to the second output path; (b) inputting an optical signal into the input path; and (c) providing photons to switch the optical shutter reversibly between the transparent state and the reflective state in order to selectively direct the optical signal to a predetermined one of the output paths. In one embodiment, the optical shutter comprises a first surface layer in a transparent state, a second surface layer in a transparent state, and a photon-absorbing layer in a transparent state and interposed between the first and second surface layers, wherein the optical shutter is characterized by the absorption of photons to change at least one of the first and second surface layers to a state of high reflectivity and to change the photon-absorbing layer to a state of opacity; and wherein the optical shutter is characterized by being reversibly imageable between the first and second states. In one embodiment, the photon-absorbing layer comprises an organic free radical compound in at least one of the first and second states.
Another aspect of this invention pertains to a method for switching an optical signal from one optical input path to a predetermined one of a plurality of different optical output paths, which method comprises the steps of (a) providing a optical switch device, comprising an optical shutter disposed between an optical input port in a first input waveguide and both a first optical output port in a first waveguide and a second optical output port in a second output waveguide, the optical shutter being switchable between a transparent state in which the light from the input port is transmitted through the optical shutter to said first output port, and a reflective state in which the light from the input port is reflected from said optical shutter to said second output port; (b) inputting an optical signal into the input port; and (c) providing photons to switch the optical shutter reversibly between the transparent state and the reflective state in order to selectively direct the optical signal to a predetermined one of the output ports. In one embodiment, the optical shutter comprises a first surface layer in a transparent state, a second surface layer in a transparent state, and a photon-absorbing layer in a transparent state and interposed between the first and second surface layers, wherein the optical shutter is characterized by the absorption of photons to change at least one of the first and second surface layers to a state of high reflectivity and to change the photon-absorbing layer to a state of opacity; and wherein the optical shutter is characterized by being reversibly imageable between the first and second states. In one embodiment, the photon-absorbing layer comprises an organic free radical compound in at least one of first and second states.
Still another aspect of the present invention pertains to a method for switching an optical signal from one or more optical input paths to a predetermined one of two or more optical output paths, which method comprises the steps of (a) providing an optical switch device, as described herein; (b) inputting an optical signal into the one or more input paths; and (c) providing photons to switch the optical shutter from the first state and the second state in order to selectively direct the optical signal to a predetermined one of the two or more output paths.
As will be appreciated by one of skill in the art, features of one aspect or embodiment of the invention are also applicable to other aspects or embodiments of the invention.


An apparatus and a method for creating a database wherein the data entry, such as a journal entry in accounting, is the canonical record can be implemented utilizing a microcomputer. A plurality of data entries to be classified are separate records each comprised of one or more items having associated quantities and an entry number serving as a pointer to the record. Each item contains information including at least an item number or label and a quantity. At least two item indicators are then generated for each of the item numbers. A mapping function is applied to each data entry to assign the item indicators for the item numbers based upon the associated quantities. The item indicators for the data entry are sorted into ascending numerical sequence and an n-dimension sparse matrix is selected where "n" is the number of items in the data entry. If the present combination of item indicators is new, a design record is created for the database based upon the sparse matrix and including the item indicators, the associated quantity sums, the total number of data entries summarized in the design record and a pointer (a chain of entry numbers) to the records of the data entry detail. The quantities for the present data entry are added to the quantity sums and the entry number is stored in the pointer chain. After all the data entries have been processed, a search routine can be utilized to review the various design records as desired.

The present invention relates generally to a system for classifying large volumes of raw data and, in particular, to a method and apparatus for optimally summarizing a plurality of data entries for efficient review, inspection, sorting, summarizing and reporting.
Many enterprises generate large volumes of data entries, each such entry having associated with it one or more items representing important information. Typically, larger enterprises are computerized and the data entries are inputted into a computer and then transferred to a mass storage device such as a magnetic tape for later use in various data analysis and report generating programs. For example, a receiving department or a stock room accepts a delivery of parts to be placed into inventory. At least the part number and quantity must be inputted into the computer for later use in inventory, manufacturing and accounting programs.
Various specialized computer programs have been written to organize large volumes of data entries. For example, U.S. Pat. No. 4,346,442 shows a program for processing data entries related to a securities brokerage/cash management system. In U.S. Pat. No. 4,694,397, there is shown a computer system for interfacing a banking system and a brokerage system. U.S. Pat. No. 4,506,326 discloses an apparatus and method for synthesizing a query for accessing a relational database. Of course, there are also many commercial database management programs available today. However, many specific applications have not been addressed.
For example, there appear to be few, if any, formal reports of the journal in the history of accounting. The first level of accounting data, the journal, has received little research attention. To many observers, the journal is merely a log of activity, i.e. the input data from which a ledger is derived. Other than the "debit-credit balance test" and the "does-the-account-exist test", computer systems often leave the completeness and correctness of accounting matters to auditors and accounting supervisors.
Nevertheless, journals have been an important part of auditing because the environment of accounting, internal control, is evaluated at this point. Auditors have struggled with the need for classification of the journal. They have used procedures of "read the journal" for manual systems and various scan and cross-reference techniques in computer systems. Many auditors feel that an "inspection of data" function has been lost in the volumes of data handled by computer accounting systems.
Leech, in his review of matrix accounting literature ("The Theory and Development of a Matrix-Based Accounting System", 1986), suggested that databases might overcome the problems associated with recording transactions in matrix accounting systems. Amer, Bailey and De ("A Review of the Computer Information Systems Research Related to Accounting and Auditing", 1987) reviewed computer audit literature and noted the lack of direction of research in accounting and auditing information systems. Most academic thought toward accounting-oriented databases is found in the "events accounting" literature, which seeks to expand the measurements made by accounting. The present invention involves the design and programming of a database which is expected to be useful to both the auditing and matrix schools of thought.

Method and electronic apparatus for the classification of combinatorial data for the summarization and/or tabulation thereof


Absorbent articles comprising odor control compositions that are not visible from the outside of the article due to placement on or next to the absorbent core wrap.

Unscented or low scented products are desired by consumers as they may be considered more natural and discreet than scented products. Manufacturers of unscented or low scented products for controlling odors rely on odor reduction ingredients or other technologies (e.g. filters) to reduce malodors. But some of the odor control compositions, while known to be effective, may not be visually attractive when incorporated into the product. Therefore, there is a continuing need for ways to control or reduce unwanted odors while maintaining an attractive appearance of the product.

Article comprising odor control composition


An aesthetically pleasing decorative cover for a water cooler or water cooler reservoir bottle helps to transform the bottle from a bottle into a likeness of a person or animal without completely covering the water cooler or water cooler reservoir bottle. The decorative cover may be a three dimensional simulation of sports headgear and can include a cap to allow the user to wear the cover in a “bobble head” fashion through a cap with elastic straps. Additional features include a liner bowl for use as a chip and/or ice bowl, and may include a pivoted handle/simulated face mask.

1. Field of the Invention
The present invention relates generally to covers for water coolers, water bottles, and water cooler reservoir bottles.
2. Background Information
German Patent DE 202004007752U1 published in 2004 discloses a drink container lamp which combines a conventional drink container with a light source and the functions of the light source are controlled by operating the opening and closing mechanism of the drink container. The light source can be arranged inside or outside the drink container. The light source can be enclosed by a transparent body outside the container.
U.S. Design Pat. No. 539,588 from 2007 discloses an ornamental cover for a water cooler. U.S. Design Pat. No. 438,425 from 2001 discloses an ornamental windowed and zippered cover for a water dispensing bottle. U.S. Design Pat. No. 479,426 from 2003 discloses an ornamental water cooler bottle cover.
U.S. Pat. No. 5,454,492 issued in 1995 discloses a decorative cover which easily fits over a water bottle mounted on a water dispenser. This cover provides a variably changeable decor that can fit different tastes and environments. Further, this cover includes accessory features such as a handle for easy removal of the cover, a cup dispenser, and a pouch for storing water delivery schedules, bills and the like. In one embodiment the cover is constructed of a loose fitting material and includes a top portion and a side portion. In an alternate embodiment the cover is constructed of a rigid material designed to stand on its own around the water bottle. In this embodiment the cover can include a top portion or can leave the water bottle exposed on the top. This rigid material can be foam rubber coated with plastic for writing and erasing messages or metallic for attaching messages by magnetic means. Both the loose-fitting and the rigid embodiments of the cover can be made with strategically positioned viewing ports in them for determining the water level in the water bottle and allowing light to reach the interior of the water bottle. The viewing ports can be made from the absence of any material or can be constructed of a Nylon mesh material. The cover can also include an interior liner which is used to absorb moisture away from the water bottle.
United States Patent No. 2003-0071068 published in 2003 discloses an illuminated water cooler. The bottled water cooler includes at least one and preferably a plurality of lights for illuminating a transparent water bottle mounted onto a cooler housing in an inverted orientation. The lights are mounted on the cooler housing for illuminating the bottle generally at a bottle shoulder along an annular contact zone supported on the cooler housing. The lights shine generally upwardly through the transparent bottle wall and into the bottle interior to illuminate the bottle and its contents, resulting in an attractive and refreshing appearance.
All of the above identified patents and publications are hereby incorporated by reference in their entireties. It is an object of the present invention to address these deficiencies of the existing prior art.

Cover for a water cooler reservoir bottle


A one-directional captive screw attachable to a panel that is hand tightenable, but requires a tool to loosen once hand tightened. The captive screw includes a screw having a head with a recess and a threaded portion, a knob having a central longitudinal axis coaxial with the screw, a one-directional ratchet between the knob and the screw. The ratchet engages to allow the screw to be tightened in a clockwise direction using the knob, and disengages when rotated in a counterclockwise direction, such that a tool is required to loosen the screw by use of the recess.

This invention relates to captive screws of the type generally used to attach an upper panel to a lower panel or frame wherein it is desired to keep the fastener in position without loose items of hardware. The captive screw is mounted on the upper panel, such that the screw stays attached to the panel even when the threads of the screw shaft are fully disengaged from a second panel to which the upper panel is attached. The present invention is particularly useful in the electronics industry. In certain applications, when doors or covers are opened or removed and a hazardous voltage exists behind these doors or covers, it is often required or desirable that the door or cover be opened or removed by using a tool. Regulations in the United States often merely require a simple screw driver. In Europe however, a Phillips driver or other tool often must be used. The present invention has the unique ability to provide for hand tightening when closing the door or panel, but requires a tool, such as a screw driver to effect removal.


A method for implementing the media gateway function is disclosed by the embodiment of the present invention, including: receiving a first signaling message; determining to perform a processing of a base station application layer or a processing of a media gateway control application layer according to a Simple Control Transmission Protocol (SCTP) link, wherein the SCTP link is indicated by the first signaling message; if determine to perform the processing of the media gateway control application layer, routing traffic data to a destination device. A radio access control device and a radio access system according to the above mentioned method are further disclosed. According to the embodiment of the present invention, the exchange number of an IP packet is reduced, and the bearer is separated from the control.

In the mobile communication network including Wideband Code Division Multiple Access (WCDMA) network and Code Division Multiple Access 2000 (CDMA 2000) network, the core network of circuit domain adopts an architecture separating bearer from control; Mobile Switching Center (MSC) has been divided into a Mobile Soft-switch device and a Media Gateway (MGW); and IP bearer network is generally used for a bearer between network entities in the mobile communication network. All IP network has become a trend in the industry.
In the CDMA2000 network, the MSC is divided into a Mobile Switching Center emulation (MSCe) and the MGW; In the WCDMA network, the MSC is divided into an MSC server and the MGW. And in the CDMA2000 network, the network radio access control device is a Base Station Controller (BSC); in the WCDMA network, the network radio access control device is a BSC or Radio Network Controller (RNC).
In the following, the CDMA2000 network is hereinafter described as an example, which is the same as the WCDMA network apart from the different entity names.
FIG. 1 is a schematic diagram illustrating the physical architecture of CDMA2000 network. A Media Resource Function Processor (MRFP) and an MGW are generally combined within one physical entity; an MSCe, MGW, BSC and MRFP/MGW generally access the IP bearer network via routers to implement the interworking between each other.
FIG. 2 is a schematic diagram illustrating the logical architecture of CDMA2000 network. In FIG. 2, the dashed line represents a signaling connection and the solid line represents a traffic data connection.
In FIG. 2, the signaling connection is mainly located between MSCes, between MSCe and MGW, and between MSCe and BSC; the traffic data connection is mainly located between BSC and MGW, and between MGWs, and the data connection between BSCs is implemented via the MGW.
A procedure of transmitting traffic data in FIG. 2 is hereinafter described. MS1 within the coverage area of BTS11 communicates with MS2 within the coverage area of BTS22. After a signaling interaction, BSC1 teams that the traffic data received from BTS11 will be transmitted to MGW1; then MGW1 learns that the traffic data received from BSC1 will be transmitted to MGW2; and MGW2 learns that the traffic data received from MGW1 will be transmitted to BSC2. As a result, in the traffic plane, after receiving the traffic data sent by MS1, BSC1 sends the traffic data to MGW1 after adding the IP address of MGW1 to the traffic data; MGW1 sends the traffic data to MOW2 after modifying the IP address of MGW1 into the IP address of MGW2; MGW2 sends the traffic data to BSC2 after modifying the IP address of MGW into the IP address of BSC2; at last, BSC2 delivers the traffic data from BTS22 to MS2.
As shown in the above description, signaling and traffic data of CDMA2000 system are all carried by IP. For the traffic data transmitted by IP between BSC and MGW, and between MGWs, the destination IP of traffic data may be directly designated in BSC and the traffic data may be routed according to the IP, since each entity takes IP as its bearer and the media access method is simple. Therefore, the forwarding function of media gateway is of no particular significance, but increases the switch number of an IP packet and wastes the system resource.
At present, a manufacturer of industry provides architecture for combining MSC with BSC device and setting an IP interface, which is shown in FIG. 3. FIG. 3 is a schematic diagram illustrating the physical architecture for combining MSC with BSC. Referring to FIG. 3, although this architecture embodies IP bearer, reduces the switch number of an IP packet and has the advantage of low cost, the operator is unable to select the device of manufacturer having the service advantage and the device of manufacturer having the radio advantage to implement the design with optimization, because the MSC and the BSC device are combined into one device and A-Interface between MSC and BSC is unable to be open.
In addition, combining MSC with BSC device is unable to embody the advantage of separating bearer from control. For example, when bearer is separated from control, an MSCe may manage multiple MGWs, and it is only necessary for upgrading a few site MSCe to add service support; however, it is necessary for upgrading all MSC/BSC combination devices in the case of combining MSC with BSC device, which improves the complexity for maintaining a system and increases the cost for maintaining a system.

Method for implementing media gateway function, radio access control device and radio access system


A fuel vapor recovery system is disclosed wherein fuel supplied to the fuel filler pipe of a vehicle is cooled by a container of a coolable phase change material. The phase change material is cooled by a thermoelectric cooling element powered by the vehicle electrical system. A heat exchange member is disposed in the filler pipe in heat conducting relation to the container containing the phase change material. The heat exchanger and container are preferably retained in the filler pipe by thermally insulative supporting members to minimize heat transfer between the container phase change material and the filler pipe.

Vehicles are refueled by dispensing fuel from underground storage tanks into a vehicle fuel tank. A small but measurable amount of fuel vapor is emitted during refueling due to the displacement of vapors from the vehicle fuel tank and release of vapors due to turbulently dispensing fuel from the refilling nozzle into the fuel filler pipe. The amount of vapor emissions varies in part based upon the temperature of the fuel dispensed into the fuel tank and the temperature of fuel within the fuel tank. The temperature of fuel obtained from underground storage tanks is approximately 65.degree.-70.degree. F. Temperature of fuel within the fuel tank which is heated by warm air flowing underneath the car from the engine and vehicle cooling systems can exceed 80.degree. F. The warmer the fuel the more volatile and greater the quantity of vapor emissions can be expected during refueling.
Prior art attempts to overcome the problem of vapor recovery during refueling have generally focused on adaptation of fuel dispensing nozzles to include vapor recovery systems. In particular, U.S. Pat. No. 3,921,412 to Heath et al. discloses a refrigeration system for fuel dispensing nozzles which condense vapors emitted from a fuel filler pipe.
Recently, environmental regulations requiring reduction of emissions during refueling have been promulgated that will necessitate on-board systems for reducing vapor emission during refueling. One approach to meeting these requirements is to provide a carbon canister at the inlet of the fuel filler pipe as proposed in U.S. Pat. No. 4,572,394 to Tanahashi et al. Carbon canister systems are expensive and add weight to vehicles which is counterproductive to fuel efficiency requirements.
The above problems have failed to provide a solution as proposed in the present invention as summarized below.

Heat exchanger for fuel filler pipe for on-board fuel vapor recovery


The present invention provides a lancet (X1) which includes a case (1) including an internal space (10), and a lancing unit (2) which includes a lancing needle (20) and which is movable within the internal space (10) in an advancing direction from a wait position to an advanced position. The case (1) includes a main body (11) accommodating the lancing unit (2), and a cap (12) which is molded integral with the main body (11) and detachable from the main body (11). The lancing unit (2) includes a cover portion (22) for covering a portion of the lancing needle (20) on the advancing side, for example. The cover portion (22) is detachable together with the cap (12) by exerting a rotational force for rotating the cap (12) and a pulling force for causing relative movement of the cap (12) in the advancing direction for exposing a front end of the lancing needle (20).

A portable blood glucose level measuring device has been put to practical use for checking the blood glucose level by an individual who stays at home or away from home. To measure the blood glucose level using such a measuring device, a biosensor may be set to the measuring device for providing an enzyme reaction field, to which blood is supplied. In doing this, a lancing apparatus having a skin-lancing needle may be used for facilitating the bleeding from the skin. From a sanitary point of view, the skin-lancing needle is provided as a disposable lancet. An example of lancet is disclosed in the gazette of JP-U-5-88503. The lancet disclosed in the gazette, suitable for reducing the manufacturing cost due to the reduced number of parts, has a structure shown in FIGS. 27A and 28A of the present application.
The lancet 8 of FIG. 27A includes a needle hub 82 supported by a housing 80 via a breakable portion 81. The needle hub 82 holds a lancing needle 83. The housing 80 is formed with a first opening 80a for allowing access to the rear end 82a of the needle hub 82 to push it, and with a second opening 80b for allowing the projection of the lancing needle 81. At the second opening 80b, a cap 84 is provided for closure. The cap 84 includes a breakable portion 84a so that the front portion 84b of the cap 84 can be removed, as shown in FIG. 27B. The front portion 84b of the cap 84 includes a needle tip accommodation space 84c.
In using the lancet 8, the front portion 84b of the cap 84 is removed, and then the rear end 82a of the needle hub 82 is fitted to a pushing member 85 of the lancing apparatus not shown in the figure. By operating the pushing member 85, the breakable portion 81 is broken, thereby permitting the needle hub 82 to move in the pushing direction (the direction indicated by the arrow A in FIG. 27). As a result, the tip of the lancing needle 83 projects forward from the second opening 80b, so that the lancing needle 83 can lance the skin. After the lancing is finished, the front portion 84b of the cap 84 is turned over, as shown in FIG. 27C, to be attached to the rear portion of the cap 84. Thus, the needle tip is accommodated in the accommodation space 84c.
The lancet 9 shown in FIG. 28A includes a housing 92 in which a needle hub 90 is held via a resilient portion 91. The housing 92 has an opening 92b to which a cap 94 is attached. The cap 94 includes a breakable portion 94a and an accommodation space 94c.
In the lancet 9 again, after the front end 94b of the cap 94 is removed, the front end of a lancing needle 93 is caused to project from the housing 92, as the rear end 90a of the needle hub 90 is pushed in the direction of the illustrated arrow A in FIG. 28B. Then, when the pushing force is removed, the restoring force of the resilient member 91 brings the needle hub 90 back to the initial position, so that the lancing needle 93 is accommodated in the housing 92.
In the lancets 8, 9 shown in FIGS. 27 and 28, the lancing needles 83, 93 are left projecting from the needle hubs 82, 90. Specifically, the lancing needles 83, 93 are embedded in the needle hubs 82, 90 by insert molding except for the front ends. However, in insert molding the lancing needles 83, 93 with the needle tips 83, 93 exposed, care should be taken so as not to bend the needle tips, which makes the manufacture difficult. Further, the needle hubs 82, 90 are formed integral with the housings 80, 90 via the breakable portion 81 or the resilient portion 91, and the molding for such an integral configuration is difficult. Moreover, in attaching the caps 84, 94 to the housing 80, 92 via the breakable portion 81 or the resilient portion 91, care should be taken so as not to bend the needle tips, which causes the operation efficiency to deteriorate. In summary, the lancets 8, 9 shown in FIGS. 27 and 28 are disadvantageous in terms of production cost because of the poor operation efficiency and difficult manufacturing process.
Further, in the lancet 8 shown in FIG. 27, the needle hub 82 and the lancing needle 83 are freely movable relative to the housing 80 after the breakable portion 81 is broken. This allows the lancing needle 83 to project from the housing 80 when the lancet 8 is detached from the lancing apparatus for disposal. Thus, there may be a danger that the lancing needle 83 may stick into a finger, for example.


A servomotor type control system for a railroad track model includes a CPU, a key unit, and multiple servos; a player of the model achieves control operating status of those servos as desired by operating the key unit in conjunction with programming pre-installed in the CPU; accordingly, multiple point rails can be easily controlled and adjusted; the servo relates to a servomotor to allow rail switching highly imitating life situation as a breakthrough of conventional restriction to significantly upgrade delicate sense and precision of a railroad track model.

(a) Field of the Invention
The present invention is related to an integrated system operated in a railroad track model for switching point rail, switch signal, or level crossing, and more particularly, to one achieving the control by a servomotor.
(b) Description of the Prior Art
Train railroad track models generally available in the market involve making real traffic facilities into imitating miniature models including track, train on the track driven by electric energy, and point rail, crossing, related signals and environments to deliver sense of real situation for meeting imitation requirements. In a railroad track model of the prior as illustrated in FIG. 1 of the accompanying drawings, point rail controlling always operate by means of a stepping motor or an EM structure. The stepping motor or the EM structure usually is in a large size, which prevents easy installation and summary speed regulation, and involves complicate wiring. Even a player has to design on own efforts associate electronic devices; other players who do not command a certain level of electrics are unable to complete the installation of the railroad track model. Furthermore, existing control systems are found with poor coordination making operating set up extremely tedious and strenuous.

Railroad track model servomotor type control system