A system and method are provided for controlling a display unit of a mobile terminal which allows for enhanced display capabilities. A controller of the mobile terminal includes an output buffer region allocated within an external memory of the controller to receive and store screen data, and a display interface to transmit the screen data directly to the display unit. Screen data is stored and transmitted based on a clock cycle associated with an internal bus of the controller, thereby increasing display speed and maximizing the capabilities of a high performance, high speed display unit.

1. Field of the Invention
The invention relates to a mobile terminal and, more particularly, to a system and method for controlling a display unit of a mobile terminal.
2. Background of the Related Art
In general, screen information (data) to be displayed on a display unit of a mobile terminal is configured and stored in an external memory such as a Random Access Memory (RAM). There are two methods typically used to display the screen information stored in the external memory.
A first related art display method is shown in FIG. 1. In this first method, a controller, such as a central processing unit (CPU) is used to configure and output the screen information. More specifically, as shown in FIG. 1, a controller 13 records screen data in a screen output buffer (not shown) of an external memory 12, reads the screen data from the screen output buffer, and outputs the data to a display unit 11.
However, this reading/writing of display data from/into the external memory 12 and outputting data to the display unit 11 requires multiple clock cycles, thus restricting performance of the display unit 11. More specifically, by using this first display method, the reading/writing time associated with the external memory 12 and the controller 13, as well as a transfer rate between the external memory 12 and the controller 13, limit the display speed, and thus the type of display unit that can be used with the related art mobile terminal.
A second related art display method is shown in FIG. 2. In this second method, screen data is configured by a controller and output by an external memory. More specifically, as shown in FIG. 2, a controller 23 configures screen data in a screen output buffer (not shown) of an external memory 22, and the external memory 22 outputs the configured screen data directly to the display unit 21.
This second related art display method is advantageous in that a lesser number of clock cycles are required for the transfer of screen information, and display data can be output to the display unit 21 more quickly than in the first related art display method.
However, this second related display method suffers deficiencies similar to this first method, in that performance of the display unit is still somewhat limited by the reading/writing time required by the external memory 22, a transfer rate between the external memory 22 and the controller 23, and a transfer rate between the external memory 22 and the display unit 21.
Thus, when screen data is configured in an external memory in accordance with these related art display methods, performance of the display unit is limited by the performance of the external memory and the interface speed. That is, since the output speed of the display unit is limited by a reading/writing time from/into the external memory by the controller, a data transfer rate between the external memory and the controller, and a data transfer rate between the external memory and the display unit, the related art mobile terminal cannot take advantage of the enhanced display capabilities associated with a high performance display unit.

System and method for controlling display of mobile terminal


A video camera capable of recording and/or reproducing multiple channel audio signals and video signals simultaneously in a single recording medium in such a manner as to reproduce omnidirectional ambient sounds as surround sound. The video camera includes a number of microphones and records first multiple audio signals obtained by processing the audio signals outputted from the microphones to generate the multiple channel audio signals and also records a second audio signal obtained by processing all of the audio signals outputted from the microphones in the recording medium simultaneously with the video signals, so that the first multiple audio signals and the second audio signal can be reproduced independently of each other.

The present invention relates to a video camera capable of recording and/or reproducing audio signals and video signals simultaneously, and more particularly to a portable video camera of such type.
It is general that a video camera is customary adapted for recording both video and audio signals simultaneously in a recording medium such as a magnetic tape for example, and with regard to sounds, improved devices having a stereophonic audio recording function with two microphones are currently popularized. Therefore, when the sounds and images recorded by a video camera are reproduced by the use of, for example, a home television receiver equipped with a color cathode ray tube as a monitor, it may be said that stereo recording is superior to monaural one in achieving enhanced vivid reproduction with the live-performance reality.
However, in any of the conventional video cameras known heretofore, even a type employing a plurality of microphones for stereophonic audio recording is capable of executing merely two-channel sound reproduction, and it is becoming difficult to comply with the predicted demand for improvements relative to attaining the live-performance reality.
Apart from a conventional large-sized theater where images and sounds shot and recorded in a silver chloride film are reproduced by means of a projector, there has been contrived a mini-theater where a magnetic tape is used for shooting and recording by a video camera, and reproduction is executed by a video projector with a video tape recorder or the like, and the latter is currently on the increase. It is observed now that such mini-theater system tends to be popular for home use as well, and the demand for enjoying the reproduced images with the enhanced live-performance reality of the sounds is also coming to be high in general homes.
More particularly, it is becoming possible that images and sounds recorded in a magnetic tape or the like by an ordinary portable video camera can be enjoyed by the use of a deluxe acoustic apparatus with a video projector including a video tape recorder and so forth and a screen or a large-sized monitor (e.g., a display unit employing a plasma liquid crystal device).
Even if the image is reproduced to be dimensionally great on a screen or a large-sized monitor, in case the stereophonic sound reproduction is executed merely in two channels, lack of the live-performance reality is unavoidable and therefore complete satisfaction is not attained. For example, if the sport activity of a user's child in a children's athletic meeting or the like has been shot dynamically, in case the actual sound recording is merely stereophonic, it is impossible to vividly reproduce the back or ambient cheering shout, hurrah, roar and so forth with actual feeling of the live-performance reality. Consequently, it is difficult to completely utilize the full function of at least the sound reproduction line in a home video/audio reproducing apparatus, hence causing some restriction in attainment of sufficient enjoyment.

Video camera with multiple microphones and audio processor producing one signal for recording


An originator device allows for a unique passphrase to be communicated to a service system. The originator device has a fixed token in which a unique platform identifier is recorded and a processor to generate a representation of the platform configuration. This representation is communicated to the registry service as a unique, platform-specific passphrase associated with the originator.

Most services require user identification. The method for proving the identity is authentication. The typical ways to provide authentication include but are not limited to authentication protocols and transmitted stored or user entered passphrase. This result of the authentication protocol or transmission of a passphrase serves as a credential proving identity. Examples of services that use these authentication methods are: LDAP, HTML documents, UDDI, etc.
For example, the Universal Description, Discovery and Integration (UDDI) architecture provides a service with which businesses can register and then utilize to publish their information as well as seek information about other businesses. LDAP stands for the Lightweight Directory Access Protocol that specifies how global directories should be structured. Directories using LDAP typically require the user to enter a user id and passphrase.
A possible pitfall for clients using these services is their vulnerability to attacks by hackers and impostors. Impostors could insert themselves into the process and usurp information, possibly sensitive, from both the client and the service. This could lead to such problems as theft of monies involved in transactions, identity theft and others.

Originator authentication using platform attestation


According to an embodiment of the invention, a method for processing a plurality of service requests in a client-server system includes server steps of receiving at least one request for service from a client and providing a level of service based on a trust level provided in the at least one request. According to another embodiment, a method of authenticating messages includes steps of: embedding authentication information into a message at the application level; downloading a script from a computer for sending the message; running said script to send said message to a server; and checking said message by said server at the network level.

Recently, we have seen increasing activities of denial of service (DoS) attacks against online services and web applications to extort, disable or impair servers. Sophisticated DoS attacks are increasingly focusing not only on low level network flooding, but also on application level attacks that flood victims with requests that mimic flash crowds. Application level DoS attacks refer to those attacks that exploit application specific semantics and domain knowledge to launch a DoS attack such that it is very hard for any DoS filter to distinguish a sequence of attack requests from a sequence of legitimate requests. Two characteristics make application level DoS attacks particularly damaging. First, application level DoS attacks emulate the same request syntax and network level traffic characteristics as that of the legitimate clients, thereby making them much harder to detect. Second, an attacker can choose to send expensive requests targeting higher layer server resources like sockets, disk bandwidth, database bandwidth and worker processes.
There are two major problems in protecting an online e-Commerce website from application level DoS attacks. First, application level DoS attacks could be very subtle, making it very difficult for a DoS filter to distinguish between a stream of requests from a DoS attacker and a legitimate client. It would be very hard to distinguish DoS attack requests from the legitimate requests even if a DoS filter were to examine any statistics (mean, variance, etc.) on the request rate, the contents of the request packet headers (IP, TCP, HTTP, etc.) and even the entire content of the request packet itself. Further, the subtle nature of application level DoS attacks make it very hard to exhaustively enumerate all possible attacks that could be launched by an adversary. Hence, there is a need to defend against application level DoS attacks without knowing their precise nature of operation.
One way to defend from DoS attacks is to permit only preauthorized clients to access the web server. Preauthorization can be implemented using SSL (secure sockets layer) or IPSec (IP security or IPSEC) with an out-of-band mechanism to establish a shared key between a preauthorized client and the web server. Now, any packets from a non-preauthorized client can be filtered at a firewall. However, requiring preauthorization may deter clients from using the online service. Also, for an open e-Commerce website like eBay or Amazon, it may not be feasible to make an exhaustive list of all clients that should be authorized to access the service. Further, it would be very hard to ensure all authorized clients will behave benignly. A DoS attack from a small subset of preauthorized clients may render the server unusable.
Challenge-based mechanisms provide an alternative solution for DoS protection without requiring preauthorization. A challenge is an elegant way to throttle the intensity of a DoS attack. For example, an image-based challenge (Turing test) may be used to determine whether the client is a real human being or an automated script. A cryptographic challenge [see X. Wang and M. Reiter, "Mitigating Bandwidth Exhaustion Attacks Using Congestion Puzzles," Proceedings of ACM CCS, 2004] may be used to ensure that the client pays for the service using its computing power. However, most challenge mechanisms make both the good and the bad clients pay for the service, thereby reducing the throughput and introducing inconvenience for the good clients as well. For instance, an image-based challenge does not distinguish between a legitimate automated client script and a DoS attack script.
An effective solution to defend against DoS attacks is to filter attack requests at the earliest point (say, the website's firewall), before it consumes much of the server's resources. The attack requests arrive from a large number of geographically distributed machines, and thus cannot be filtered on the IP prefix. Some websites require password and login information before a client can access the website. However, checking the site-specific password requires establishing a connection and allowing unauthenticated clients to access socket buffers and worker processes, making it easy to mount an attack on the authentication mechanism itself. Some sites use strong digital signature based transport level authentication mechanisms [e.g., secure sockets layer, SSL]; however, the complex server-side computations required for verifying a digital certificate allow an adversary to target the handshake protocol for launching DoS attacks. In general, authentication mechanisms that operate at a higher layer in the networking stack allow an attacker to target lower layers.
Some websites may use message authentication codes (MAC) based IP level authentication mechanisms like IPSec. IPSec with preconfigured keys allows packets from unauthenticated clients to be dropped by the firewall. Hence, unauthenticated clients cannot access even low level server resources like socket buffers and transmission control blocks (TCBs). However, IPSec breaks client transparency in several ways: (i) Installing IPSec requires changes to the client-side networking stack, (ii) Installing IPSec requires superuser privileges at the client, (iii) IPSec permits both manual key set up and key exchange using the Internet key exchange protocol (IKE). The IKE protocol uses the Diffie-Hellman key exchange protocol. Similar to digital signatures, this protocol imposes a heavy computational load on the server, thereby allowing an adversary to target the IKE protocol for launching DoS attacks. (iv) Manually setting up shared keys circumvents the expensive IKE protocol. However, manual IPSec key setup requires superuser privileges at the client.
There is an inherent conflict between using client authentication for defending against DoS attacks and client transparency. It appears that an effective defense against DoS attacks must operate at lower layers in the networking stack so that the firewall can filter a packet before it can consume much resources at the server. On the other hand, introducing an authentication header at lower layers in the networking stack annuls client transparency, usually by requiring changes to the client-side network stack and by requiring superuser privileges at the client. Therefore, there is a need for a solution that overcomes the aforementioned shortcomings.

Method for protecting against denial of service attacks using trust, quality of service, personalization, and hide port messages

International Business Machines Corporation


An optical pickup device includes a light source to emit light, an objective lens to focus the light on a recording medium to form a light spot, an optical path changer on an optical path between the light source and the objective lens to change the path of incident light, a chromatic aberration correction lens disposed on an optical path between the light source and the objective lens, and a photodetector to receive light which is reflected from the recording medium and is then incident thereon through the optical path changer. The chromatic aberration correction lens corrects a chromatic aberration occurring due to a change in the wavelength and/or due to an increase in a wavelength bandwidth of the light. The chromatic aberration correction lens includes at least two lenses such that a lens having a positive power and a lens having a negative power are adjacent to each other.

1. Field of the Invention
The present invention relates to an optical pickup device, and more particularly, to an optical pickup device having a chromatic aberration correction lens to correct a chromatic aberration caused by a change in a wavelength and/or an increase in a wavelength bandwidth of light emitted from a light source, occurring when changing a recording/reproducing power output.
2. Description of the Related Art
The recording capacity of an optical recording and reproducing apparatus is determined by the size S of a light spot formed on an optical disc by the objective lens of an optical pickup device. Generally, the size S of the light spot is proportional to a wavelength λ and is inversely proportional to a numerical aperture (NA). Accordingly, to obtain a higher information recording density than that obtained on conventional optical discs such as CDs or DVDs, an optical pickup device (hereinafter, referred to as a high density optical pickup device) used for next generation DVDs (hereinafter, referred to as HD-DVDs) under development is anticipated to use a light source emitting blue light and an objective lens having a NA of at least 0.6, to reduce the size of the light spot formed on the optical disc.
However, an optical material such as glass or plastic used as the material of the objective lens in the conventional optical pickup device has a very steep change in refractivity in a wavelength band shorter than 650 nm. Table 1 shows changes in refractivity of M-BaCD5N, which is manufactured by Hoya and is used as a glass material for molding the objective lens, according to a wavelength.
TABLE 1Change in refractivity of M-BaCD5NChange in wavelengthglass manufactured by Hoya650 nm → 651 nm0.000038405 nm → 406 nm0.000154
As seen from Table 1, an optical material has a change in refractivity with respect to a small wavelength change of about 1 nm in a short blue wavelength band, for example, a 405 nm wavelength band, four times larger than in a 650 nm wavelength used in a conventional DVD optical pickup device. Such a steep change in refractivity of the optical material with respect to blue light causes a high density optical recording and reproducing apparatus using a blue light source to be defocused, thereby degrading performance.
In other words, an optical recording and reproducing apparatus uses different recording light power and reproducing light power. This change in the light output power between recording and reproduction causes the wavelength change. For example, in the case of the blue light source, the change in the wavelength is about 0.5-1 nm. Usually, when the output of the light source increases, the wavelength of light emitted from the light source is longer. Accordingly, the high density optical pickup device using blue light has a large chromatic aberration in the objective lens designed for a reference wavelength due to the change in the wavelength during switching between recording light output power and reproducing light output power, causing defocus.
For example, as shown in FIGS. 1 through 3, an objective lens, which has a numerical aperture of 0.65 and is designed for a wavelength of 405 nm, has a large wavefront aberration (also referred to as an optical path difference (OPD)) and defocus with respect to a fine change of about 1 nm in wavelength. FIG. 1 is a graph illustrating intensities of light spots formed on an optical disc according to defocus resulting from a change in light output power between recording and reproduction. FIGS. 2 and 3 are graphs illustrating the amount of the OPD and the amount of defocus, respectively, of the objective lens having a numerical aperture of 0.65, according to the change in the wavelength.
Although defocus caused by the change in the wavelength can be corrected by adjusting the objective lens, it takes a relatively long time to actuate the objective lens using an actuator and to follow the change in the wavelength, and during this time, the quality of a recorded or reproduced signal is degraded. Defocus occurring when output power increases for recording results in a lack of recording light power, and defocus occurring when output power decreases for reproduction increases jitter.
In other words, when the output power of the light source increases when recording information on the optical disc, the wavelength of light emitted from the light source is relatively long, for example, 406 nm, so that the light spot formed on the optical disc is defocused. Until the actuator is adjusted in response to the defocus, recording cannot be performed. Then, when the output power of the light source decreases for reproduction, the wavelength of light emitted from the light source is relatively short, for example, 405 nm. Since the actuator has been adjusted with respect to the lengthened wavelength, the light spot is defocused again. As shown in FIG. 4, the jitter increases in the reproduced signal due to defocus. FIG. 4 is a graph illustrating the amount of jitter in the reproduced signal according to the amount of defocus when the objective lens designed with respect to a reference wavelength of 405 nm and having a numerical aperture of 0.65 is used.
Moreover, when the light source is actuated at a high frequency (HF) to reduce feedback noise of the light source due to light reflected from the optical disc to the light source, a wavelength bandwidth of the light source increases, resulting in chromatic aberration, and this chromatic aberration degrades the reproduced signal.
Accordingly, a high density recordable optical pickup device capable of recording and reproducing repeatedly is required to have an optical system capable of suppressing or correcting chromatic aberration resulting from a change in the wavelength of light emitted from the light source due to the change in output power between recording and reproduction. Japanese Patent Publication No. hei 9-311271 discloses a structure employing a refraction/diffraction-monolithic-type objective lens to correct chromatic aberration resulting from a change in wavelength. A conventional refraction/diffraction-monolithic-type objective lens is an aspheric lens whose surface receiving or emitting light is aspheric. Diffraction patterns are integrally formed on this aspheric surface so that a refractive lens and a diffraction lens are integrated into a single lens.
The refraction/diffraction-monolithic-type objective lens is designed to satisfy (1+VHOE/V)(n2−1)>0.572 when it is assumed that refractivities of the lens at a central wavelength λ1, a minimum wavelength λ2 and a maximum wavelength λ3 of light emitted from a semiconductor laser are n1, n2 and n3, and that the Abbe numbers of the refractive lens and the diffraction lens are V=(n2−1)/(n1−n3) and VHOE=λ2(λ1−λ3), respectiv conventional refraction/diffraction-monolithic-type objective lens has a numerical aperture of at least 0.7 and can remove chromatic aberration due to the change in the wavelength of light emitted from the semiconductor laser. However, an optical pickup device employing the conventional refraction/diffraction-monolithic-type objective lens cannot obtain sufficient output power necessary for recording since optical efficiency is lowered to about 70-85% due to the properties of the diffraction lens.

Optical pickup device having chromatic aberration correction lens


In a method of vacuum packaging a MEMS device, at least one MEMS device is attached on a substrate. A solder preform is printed on the substrate at the perimeter surrounding the substrate. A lid is attached to the solder preform wherein the lid provides a cavity enclosing the at least one MEMS device. A first reflowing step reflows the solder at a first temperature, partially sealing the lid/substrate interface and at the same time does the outgassing and baking procedure for the packaging. Flux is applied onto an outer ring of the solder preform and a second step reflows the solder at a second temperature, completely sealing the lid/substrate interface and providing a vacuum cavity enclosing the at least one MEMS device.

(1) Field of the Invention
This invention is related to MEMS devices, and more particularly, to methods of packaging MEMS devices in a vacuum cavity.
(2) Description of the Related Art
Micro-electro-mechanical systems (MEMS), the smallest functional machines that can be manufactured currently, are made up of components ranging from a few micrometers to several millimeters in size. MEMS, a rapidly growing semiconductor field, has many important practical and potential commercial applications. There are a range of commercially available MEMS products including gyroscopes, pressure sensors, fluid regulators, optical switches, displays, mass data storage, biological sensors and chemical controllers, and so on.
A scanning mirror type of MEMS device usually relies on the mechanical oscillation of a suspended microstructure via one or pairs of torsion beams. The structure is electrostatically deflected by energizing at least one actuation electrode in interdigital comb or parallel plate configuration. In order to minimize any air damping or random disturbance during operation, such optical MEMS devices are preferred to be vacuum packaged. Vacuum packaging also provides a benefit of minimizing contamination adsorption.
Device level vacuum packaging involves a complicated package design and sealing process. Commonly, the vacuum package using a lid seal method requires a through hole on the lid, a collapsible sealing gap, or expensive machines having the capability of manipulating assembly parts in a vacuum so the package cavities can be evacuated through the venting hole or the sealing gap or when the parts are not in an intimate contact position. The vacuum sealing is closed by a final solder reflow sealing process. Furthermore, before vacuum seal, the package materials usually require extended hours of bake out at an elevated temperature in order to prevent significant outgassing.
<<Wafer-level hermetic cavity packaging>> by George A. Riley, Advanced Packaging Magazine, May 2004, discusses various types of packaging including vacuum packaging for MEMS devices. U.S. Pat. No. 6,297,072 to Tilmans et al discloses a vacuum packaging method for a MEMS device comprising making an indent in a solder ring, forming the vacuum cavity, then reflowing the solder to close the indent and seal the package.
A number of patents discuss MEMS packaging. U.S. Pat. No. 6,852,926 to Ma et al describes a seal ring contacting a bond ring to form a hermetic seal around a MEMS device in a cavity that may contain a vacuum. U.S. Pat. No. 7,491,567 to DCamp et al discloses a solder preform between the MEMS die and the seal ring. The preform is melted and then the package is sealed by soldering. U.S. Pat. No. 6,844,606 to Logsdon et al teaches first reflowing solder to attach a chip to a carrier, then using a solder alloy as a seal ring having a lower reflow temperature than the first solder. U.S. Pat. No. 7,517,712 to Stark shows a solder preform heated to form a solder joint. U.S. Pat. No. 7,298,030 to McWilliams et al describes a sealed chip package using a solder preform. U.S. Pat. No. 7,259,449 to Floyd teaches forming a metal seal, such as solder.

MEMS device package with vacuum cavity by two-step solder reflow method


A traffic control device that controls traffic of data transmitted from mobile units that belong to different groups, includes a memory, and a processor coupled to the memory, configured to switch an output destination for the data in accordance with a group and a type of the data, store the data to a plurality of data storage sections on a first-in-first-out basis, adjust an output timing for the stored data in accordance with the group and the type of the data, and attach an identifier to the data output from the plurality of data storage sections in accordance with the group and the type of the data.

In communication networks such as stationary communication networks and mobile communication networks, the number of network configurations is proportional to the number of communication carriers. Communication carriers such as public service businesses and public business system operating organizations possess a communication network for providing their services and applications.
The communication carriers provide services on the communication network, and the services are roughly divided into real-time data communication such as voice communication and non-real-time communication such as data packet communication. These services are not necessarily provided through individual networks.
Although the communication carriers provide a diversity of services and applications, there is not a significant difference among the communication carriers as to how to use the communication network system. Therefore, the network is occasionally commonly used at the application level to provide certain services, of the same kind, for example, by mobile virtual network operators (MVNOs), for example. Technologies for common use of a network through packet control are known in the art. Such technologies are disclosed, for example, in Japanese Laid-open Patent Publication No. 2007-184988, Japanese Laid-open Patent Publication No. 2010-219655, Japanese Laid-open Patent Publication No. 2004-364150, and Japanese Laid-open Patent Publication No. 2006-222592.

Traffic control device, traffic control method, and communication system


The brightness of a TIR-based display is enhanced with a registered reflective element by recycling and reflecting light that passes through the dark pupil region of each hemi-spherical protrusion in the hemi-spherical surface back to the viewer. A method to fabricate a brightness enhanced TIR display comprising an apertured membrane with a thin conductive reflective metal layer facing and registered with the pupils of the hemi-spherical surface.

FIG. 1 depicts a portion of a prior art reflective (i.e. front-lit) frustrated total internal reflection (TIR) modulated display 10 of the type described in U.S. Pat. Nos. 6,885,496; 6,891,658; 7,760,417 and 8,040,591. These patents describe an entirely new design of the outward sheet that was previously described in U.S. Pat. Nos. 5,959,777; 5,999,307; 6,064,784; 6,215,920; 6,304,365; 6,384,979; 6,437,921; 6,452,734 and 6,574,025 which comprised of, for example, various spatially uniform prism structures, dielectric light fibers, parallel, and perpendicular and interleaved structures. As a result of the closely packed, spherical or hemi-spherical beaded, outward sheet design first described in patents '496' and '658', the practical angular viewing range of frustrated TIR or other reflective display methods was increased. The new design offers semi-retro-reflective gain, whereby light rays which are incident on the surface of the convex protrusions in the shape of hemispherical beads are reflected back (but not exactly retro-reflected) toward the light source; which means that the reflection is enhanced when the light source is overhead and slightly behind the viewer, and that the reflected light has a diffuse characteristic giving it a white appearance, which is desirable in reflective display applications.
Display 10 in FIG. 1 includes a transparent outward sheet 12 formed by partially embedding a large plurality of high refractive index (e.g. η1>˜1.90) transparent spherical or approximately spherical beads (it is noted that said spherical or approximately spherical beads may also be "hemi-spherical beads" or "hemi-beads" or "beads" or "hemi-spherical protrusions" or "hemi-spheres" or "convex protrusions" and these terms may be used interchangeably) 14 in the inward surface of a high refractive index (e.g. η2≈η1) polymeric material 16 having a flat outward viewing surface 17 which viewer V observes through an angular range of viewing directions Y. The "inward" and "outward" directions are indicated by double-headed arrow Z. Beads 14 are packed closely together to form an inwardly projecting monolayer 18 having a thickness approximately equal to the diameter of one of beads 14. Ideally, each one of beads 14 touches all of the beads immediately adjacent to that one bead. Minimal interstitial gaps (ideally, no gaps) remain between adjacent beads.
An electro-active TIR-frustrating medium 20 is maintained adjacent the portions of beads 14 which protrude inwardly from material 16 by containment of medium 20 within a reservoir 22 defined by lower sheet 24. An inert, low refractive index (i.e. less than about 1.35), low viscosity, electrically insulating liquid such as, but not limited to, Fluorinert™ perfluorinated hydrocarbon liquid (η3˜1.27) available from 3M, St. Paul, Minn. is a suitable fluid for the medium 20. Other liquids such as Novec™ also available from 3M may also be used as the fluid for medium 20. A bead:liquid TIR interface is thus formed. Medium 20 contains a finely dispersed suspension of light scattering and/or absorptive particles 26 such as inorganic or organic pigments, dyes, dyed or otherwise scattering/absorptive silica or latex particles, etc. Sheet 24's optical characteristics are relatively unimportant as sheet 24 need only form a reservoir for containment of electro-active TIR-frustrating medium 20 and particles 26, and serve as a support for backplane electrode 48.
In the absence of TIR-frustrating activity, as is illustrated to the right of dashed line 28 in FIG. 1, a substantial fraction of the light rays passing through sheet 12 and beads 14 undergoes TIR at the inward side of beads 14. For example, representative incident light rays 30 and 32 are refracted through material 16 and beads 14. The light rays undergo TIR two or more times at the bead:liquid TIR interface, as indicated at points 34 and 36 in the case of ray 30; and indicated at points 38 and 40 in the case of ray 32. The totally internally reflected rays are then reflected back through beads 14 and material 16 and emerge as rays 42 and 44 respectively, achieving a "white" appearance in each reflection region or pixel.
A voltage can be applied across medium 20 via electrodes 46 and 48 which can for example be applied by, for example, vapor-deposition to the inwardly protruding surface portion of beads 14 and to the outward surface of sheet 24. Electrode 46 is transparent and substantially thin to minimize its interference with light rays at the bead:liquid TIR interface. Backplane electrode 48 need not be transparent. If TIR-frustrating medium 20 is activated by actuating voltage source 50 to apply a voltage between electrodes 46 and 48 as illustrated to the left of dashed line 28, suspended particles 26 are electrophoretically moved into the region where the evanescent wave is relatively intense (i.e. within about 0.25 micron of the inward surfaces of inwardly protruding beads 14, or closer). When electrophoretically moved as aforesaid, particles 26 scatter or absorb light, thus frustrating or modulating TIR by modifying the imaginary and possibly the real component of the effective refractive index at the bead:liquid TIR interface. This is illustrated by light rays 52 and 54 which are scattered and/or absorbed as they strike particles 26 inside the thin evanescent wave region at the bead:liquid TIR interface, as indicated at points 56 and 58 respectively, thus achieving a "dark" appearance in each TIR-frustrated non-reflective absorption region or pixel. Particles 26 need only be moved outside the thin evanescent wave region, by suitably actuating voltage source 50, in order to restore the TIR capability of the bead:liquid TIR interface and convert each "dark" non-reflective absorption region or pixel to a "white" reflection region or pixel.
As described above, the net optical characteristics of outward sheet 12 can be controlled by controlling the voltage applied across medium 20 via electrodes 46 and 48. The electrodes can be segmented to electrophoretically control the particles suspended in the TIR frustrating, low refractive index medium 20 across separate regions or pixels of sheet 12, thus forming an image.
As shown in FIGS. 2A-2G of a closer examination of an individual hemi-bead 60, reflectance of a the hemi-bead 60 is maintained over a broad range of incidence angles, thus enhancing display 10's wide angular viewing characteristic and its apparent brightness. For example, FIG. 2A shows hemi-bead 60 as seen from perpendicular incidence—that is, from an incidence angle offset 0° from the perpendicular and r is the radius of the hemispherical bead. In this case, the portion 80 of hemi-bead 60 appears as an annulus. The annulus is depicted as white, corresponding to the fact that this is the region of hemi-bead 60 which reflects incident light rays by TIR, as aforesaid. The annulus surrounds a circular region 82 which is depicted as dark, also referred to as the "pupil", corresponding to the fact that this is the non-reflective region of hemi-bead 60 within which incident rays pass through and may be absorbed and do not undergo TIR. FIGS. 2B-2G show hemi-bead 60 as seen from incident angles which are respectively offset 15°, 30°, 45°, 60°, 75°, and 90° from the perpendicular. Comparison of FIGS. 2B-2G with FIG. 2A reveals that the observed area of reflective portion 80 of hemi-bead 60 decreases only gradually as the incidence angle increases. Even at near glancing incidence angles (e.g. FIG. 2F) an observer will still see a substantial part of reflective portion 80, thus giving display 10 shown in FIG. 1 a wide angular viewing range over which high apparent brightness is maintained.

Registered reflective element for a brightness enhanced TIR display


An immunoassay method that integrates a sample processing component that enables the testing of a variety of environmental matrixes and the components for performing the method, wherein the immunoassay utilizes a monoclonal anti-PCB antibody to detect the presence or absence of PCB based contamination in a sample when tested in a field or laboratory location.

1. Field of the Invention
The present invention relates to methods, compositions and kits for performing PCB immunoassays.
2. Discussion of the Background
Testing is an essential, and integral, component of all environmental protection and restoration activities. It is the rate limiting element that influences the time, cost, and overall efficiency of project management.
The management of toxic waste sites usually involves a progression through the stages of identification, characterization, remediation and monitoring, with testing being performed during each phase. Reference laboratory methods can effectively identify and quantify unknown compounds in a sample, but become relatively inefficient when used to rapidly locate contamination (i.e., mapping), and assist in remediation and monitoring activities. The complexity of laboratory protocols, and the proximity of the labs to the test site, delays the availability of information and increases the cost of data. The ultimate cost is in the time required by the field crews. Effective field screening methods can increase the efficiency of the clean-up process by providing an on-site, high-throughput, and cost-effective way to locate contamination and manage its remediation.
The Environmental Protection Agency (EPA) has long promoted and supported the concept of screening methods to supplement laboratory analysis and increase overall efficiency. The need for more effective methods has been recognized in the Superfund Amendments and Reauthorization Act of 1986 which specifies the development and evaluation of alternative time and cost-saving methods that will assist in the eventual remediation of the nations Superfund sites.
Effective field screening methods can increase the efficiency of site management and improve overall data quality when used to supplement the services of regional laboratories. The development of these methods, however, requires a technology that will be compatible with numerous compounds and matrixes and yet be simple, effective and rugged enough to be incorporated into a protocol for use in the field.
Screening methods need to provide fast, simple, cost-effective and reliable information when operated under field conditions. The reagents and equipment should be portable and stable at ambient conditions, and the claims relating to performance should accurately reflect anticipated field use. The methods should be able to rapidly provide an ample quantity of data, and the protocol should be simple to perform and safe to use. Performance characteristics relative to sensitivity, freedom from matrix interferences and cross-reacting compounds, and correlation to an acceptable reference method should be carefully evaluated. Developers must maintain high, and consistent, quality standards relative to the consistency of their manufacturing protocols, the adequacy of in-process and pre-release quality control methods, and the reliability of their product claims. A necessary characteristic of particular significance for screening methods, is that they exhibit a very low frequency of false negative results.
Screening methods detect contamination at specified concentrations. The concentration may relate to a hazardous threshold, a clean-up target, or a process-control parameter. The potential implications of false negative data far outweigh those of false positive results. The consequence of a false positive, while a costly problem that needs to be minimized, results in additional testing or treatment. False negative data, however, provides an erroneous perception of a clean site, and may have serious environmental and legal consequences. Safeguards that minimize the incidence of false negative results are imperative. Appropriate control over the frequency of false positive data needs to be established and maintained.
The field of immunochemistry,, and the development of immunoassay technology, has been evolving since the late 19th century. However, the majority of these methods have been developed for use by the medical community. These methods have achieved a reputation for reliability and cost-effectiveness. Literally hundreds of immunoassays have been developed for such applications as drug testing, Therapeutic Drug Monitoring (e.g. digitalis derivatives, anti-asthma formulations, anti-epileptic regents, antibiotics), pregnancy testing, hormone testing (e.g., thyroxine, thyroid stimulating hormone), tests for pathological markers (e.g. lactic dehydrogenase isozymes, creatine kinase isozymes), tests for acute phase proteins (e.g., carcinoembryonic antigen, alpha fetoprotein) and tests for tumor marker proteins.
Environmental applications have been explored for the better part of a decade and a number of immunoassay methods have been developed. Most have been used for the detection of herbicides and pesticides in aqueous matrixes. The application of immunoassay technology to the testing of solid waste, complex matrixes, and highly lipophilic compounds, has provided unique challenges for the chemist. The feasibility of developing such methods, however, has been demonstrated with immunoassays for single compounds such as Dioxin (see, for example, Vanderlaan et al, Environmental Toxicology and Chemistry, 7:859-870, 1988; and Stanker et al, Toxicology, 45:229-243, 1987).
The history of immunoassay technology can be traced to 1900 when Karl Landsteiner described the A, B and Zero (0) blood types after observing the agglutination reaction (i.e., aggregation) that resulted when he mixed the erythrocytes and serum for several of his co-workers on a slide. His observation became the basis for present day blood typing methods. Landsteiner remained a dominant figure in immunology for the next 40 years performing numerous experiments that demonstrated the extraordinary specificity of the antibody binding reaction. He introduced the term "hapten" to define compounds that are unable to directly stimulate antibody production when injected into an animal, but are capable of binding to an antibody if they are produced by an alternate means. Most environmental chemicals are haptens, and although potentially toxic, will not stimulate the immune system to respond.
For 50 years following Landsteiner's discovery, immunoassay technology continued to rely upon the binding and cross-linking ability of an antibody to cause agglutination, cell lysis, and protein flocculation reactions. These methods were relatively insensitive when compared to the immunoassay methods of today, and better suited to the analysis of larger compounds and organisms (e.g. bacteria, proteins). A major advance occurred in the 1950's when Drs. Berson and Yalow, while investigating the metabolism of radio-labelled insulin administered to diabetic patients, observed the production of anti-insulin antibodies in the serum of these patients (see Principles of Competitive Protein Binding Assays, Second Ed., Odell, W. D. and Franchismont, P. (Eds.); Wiley and Sons, New York). They described a radioimmunoassay (RIA) method in 1959 that used anti-insulin antibody molecules and radio-labelled insulin in a highly sensitive procedure to quantify insulin levels in the serum. The RIA method used a competitive antibody binding reaction, where radio-labelled insulin and sample insulin compete for a limited number of antibody binding sites. In 1977, Rosalyn Yalow was awarded the Nobel Prize in Medicine for her work on the development of the radioimmunoassay method for peptide hormones (see Basic and Clinical Immunology, 7th Ed. Stites, D. P. and Ten, A. I. editors; Appleton and Lange, Conn., 1991). RIA rapidly became a universally accepted method that demonstrated exceptional specificity, sensitivity, and simplicity.
A simpler, safer, and more convenient immunoassay was reported in 1971, when two independent research teams, Engvall and Perlmann, and Van Weeman and Shuurs, simultaneously disclosed a competitive immunoassay method that used an enzyme-labelled conjugate instead of a radio-labelled-conjugate to produce a test that generated a visible end-point signal (see Engvall et al, Immunochem. 8:871-874, 1971 and Van Weeman et al, FEBS Letters, 15:232-236, 1971). The new ELISA (i.e., enzyme linked immunosorbent assay) method eliminated the problems associated with the safety, disposal and detection of radioactive reagents. The method offered long term stability, the opportunity to generate quantifiable data using instruments commonly available in most laboratories, and a mechanism to develop separation-free (homogeneous) procedures and simple qualitative screening tests.
Current immunoassay technology benefits from the diversity of detection systems developed that use enzyme-catalyzed chromogenic reactions, radionuclides, chemiluminescence, fluorescence, fluorescence polarization and a variety of potentiometric and optical biosensor techniques. Improvements in the sensitivity achieved has necessitated the generation of new descriptive nomenclature for methods that can now detect "zeptomolar" (10.sup.-21, 600 molecules) concentrations.
Immunoassay methods combine the specific binding characteristics of an antibody molecule with a read-out system that is used to detect and quantify compounds. Antibodies are binding proteins that are produced by the immune system of vertebrates in response to substances that are perceived to be foreign.
The physiological role of antibody, or immunoglobulin, molecules is to bind, and thereby label for destruction, the perceived foreign substance. Antibody molecules are synthesized by a subset of lymphocytes, termed B lymphocytes, that become activated to produce antibody after exposure to substances having prerequisite size, complexity and "foreignness" to the host organism. Antibodies are large, polymeric proteins (i.e. .gtoreq.1.5.times.10.sup.5 d), that can be classified into sub-populations on the basis of their sequence, size and number of subunits. Five major populations, or isotypes, exist carrying the designations of IgM, IgA, IgD, IgG and IgE, with immunoglobulin G (IgG) usually found in the highest concentration.
Immunochemical assays are reliable when used in the screening of soil for contamination and have been used commercially for the rapid analysis of a variety of compounds (see Nqo, in Enzyme-Mediated Immunoassay, eds., Debtor et al, Plenum Press: New York, 3 (1985); Odell, in Principles of Competitive Protein-binding Assays; eds., Odell et al, J. Wiley & Sons, New York, 1 (1971); Quantitative Enzyme Immunoassay; Blackwell Scientifid, Oxford (1978); Engvall, in Enzyme Immunoassay, eds., E. Ishikawa et al, Igaku-Shoin, New York, 1 (1981); Jaklitsch, in Enzyme-Mediated Immunoassay, eds., Debtor et al, Plenum Press, New York, 33 (1985)), and have been developed to detect a number of different compounds of environmental concern (see Immunochemical Methods for Environmental Analysis; ACS Symposium Series 442; Amer. Chem. Soc., Washington, DC (1990); Mapes et al, Bull. Environ. Contam. Toxicol. 49, in press (1992); Immunoassays for Trace Chemical Analysis; ACS Symposium Series 451, Amer. Chem. Soc., Washington, DC (1990); Harrison et al, in Biotechnology for Crop Production, Hedin et al, eds., ACS Symposium Series 379; Amer. Chem. Soc.: Washington, DC, 316 (1988); Hammock et al, in Recent Advances in Pesticide Analytical Methodology; Harvey et: al, eds., ACS Symposium Series 136; Amer. Chem. Soc.: Washington, DC, 321 (1980); Van Emon et al, in Analytical Methods for Pesticide and Plant Growth Regulators Vol. XXII, 217 (1989); Albro et al, Tox. & Appl. Pharm. 50:137 (1979); Blewett et al, Bull. Environ. Contam. Toxicol. 45:120 (1990); Bushway et al, Bull. Environ. Contam. Toxicol. 40:647 (1988); Fleeker et al, in Immunoassays for Monitoring Human Exposure to Toxic Chemicals; Vanderlaan et al, eds., ACS Symposium Series #451 (1991); Gee et al, J. Agric. Food Chem. 36:863 (1988); Goh et al, Bull. Environ. Contam. Toxicol. 46:30 (1991); Harrison et al, Agric. Food Chem. 37:958 (1989); Jung et al, J. Agric. Food Chem. 37:1183 (1989); Jung et al, Pesticide Science 26:303 (1989); Thurman et al, Anal. Chem. 62:2043 (1990)).
One of the most serious problems in environmental contamination is the presence of polychlorinated biphenyls (PCBs). PCBs, as commercially available, exist as mixtures of PCB congenors containing various mixtures of 209 different isomeric forms. These mixtures were distributed commercially under the commercial name AROCLOR. A number assigned to the AROCLOR designation indicates average percent chlorination of the PCB congenors in the product. Thus, AROCLOR 1260 contains PCBs with an average chlorination of 60%, AROCLOR 1254 has an average chlorination of 54%, AROCLOR 1248 has an average chlorination of 48%, AROCLOR 1242 has an average chlorination of 42%, and AROCLOR 1232 has an average chlorination of 32%. The only one of the important toxic AROCLORs which does not follow the above rule is AROCLOR 1016, which has an average chlorination of 41%. Toxicological data has indicated that the highly chlorinated PCBs are the most toxic to human health. The most frequently encountered toxic AROCLORs are AROCLOR 1260, AROCLOR 1254, AROCLOR 1016, AROCLOR 1232, AROCLOR 1242 and AROCLOR 1248. However, since the composition of PCB products varies from individual product to individual product, from manufacturer to manufacturer within the same product, and even from lot to lot within the same product, immunoassay test development is difficult.
Mattingly et al, U.S. Pat. No. 5,145,790, disclose an immunoassay based method for detecting polychlorinated biphenyls. However, the Mattingly et al method requires the use of a combination of antibodies in order to detect both the highly chlorinated biphenyls, such as AROCLORs 1260 and 1254, as well as the lower chlorinated biphenyls, including AROCLORs 1016, 1221, 1232, 1242, and 1248. Thus, in order to use Mattingly et al in a screening program at a contamination site, one would be required to either test each sample multiple times with different antibodies, or to use mixtures of antibodies in a test.
Under the Toxic Substances Control Act, the U.S. Environmental Protection Agency (EPA) requires the cleanup of all spills and discharges where the spilled material contains more than 50 ppm of PCBS. Contaminated surfaces are required to be cleaned to 10 .mu.g/100 cm.sup.2 or 100 .mu.g/100 cm.sup.2, depending on the nature of the surface. To determine (1) if a cleanup is necessary and (2) whether such a cleanup has been effective, the EPA requires that standard wipe tests be performed on the surface. In 40 CFR 761.123 the EPA defines a "standard wipe test":
. . "Standard wipe test" means, for spills of high concentration PCBs on solid surfaces, a cleanup to numerical surface standards and sampling by a standard wipe test to verify that the numerical standards have been met. This definition constitutes the minimum requirements for an appropriate wipe testing protocol. A standard size template (10 centimeters (cm).times.10 cm) will be used to delineate the area of cleanup; the wiping medium will be a gauze pad or glass wool of known size which has been saturated with hexane. It is very important that the wipe be performed very quickly after the hexane is exposed to air. EPA strongly recommends that the gauze (or glass wool) be prepared with hexane in the laboratory and that the wiping medium be stored in sealed glass vials until it is used for the wipe test. Further, EPA requires the collection and testing of field blanks and replicates.
In 40 CFR 761.130(e) the EPA also recommends a study by the Midwest Research Institute (MRI) which describes a standard wipe test in more detail. The report proposal leaves a considerable amount of latitude to the analyst as to how the sampling and analysis are to be performed ("Verification of PCB Spill Cleanup by Sampling and Analysis", pp. 41-42).
Thus, an immunoassay method is needed which will provide reliable, accurate and fast results in the field for a wide range of PCB contaminants in a single test using a single antibody, regardless of manufacturer, exact composition or matrix. Such an assay would increase the efficiency of environmental site management activities such as characterization (mapping), remediation monitoring, and regulatory compliance.
In addition, a standard PCB wipe test is needed which will provide reliable, accurate and fast field results in accordance with EPA guidelines.

Polychlorinated biphenyls (PCB) immunoassay method, its components and a kit for use in performing the same


Systems, methods and articles of manufacture for GPS coordinate determination for images are described herein. Embodiments of the present disclosure relate to equipping an image with GPS coordinates where the image is uploaded onto a mapping site without GPS coordinates. The mapping site is able to equip the image with GPS coordinates by identifying a recognizable structure in the image and then comparing the recognizable structure with stored structures in the mapping site. The stored structures in the mapping site have GPS coordinates for each. The mapping site compares the recognizable structure of the image without GPS coordinates to a structure stored in the mapping site with GPS coordinates. The mapping site then tags the image without GPS coordinates with the GPS coordinates associated with the stored structure that matches the structure of the image.

Mapping sites provide virtual maps of the Earth by the superimposition of images obtained from but not limited to satellite imagery, aerial photography, and geographic information system data. Image sharing sites provide users with the capability to upload images to be viewed by the public on the image sharing sites. Mapping sites may also provide image sharing capabilities to users where users may upload images into the mapping site to be viewed by the public on the mapping site. Mapping sites with image sharing services display the uploaded images in the geographic location of the image on the mapping site.
For example, an uploaded image of the Eiffel Tower located in Paris, France would be displayed on the mapping site in the geographic location of the Eiffel Tower in Paris, France. Mapping sites require that the images uploaded have embedded global positioning system (GPS) coordinates so that the mapping site may display the uploaded image in the proper geographic location of the image on the mapping site.

This patent is subject to a terminal disclaimer.


An apparatus for cutting a suture is provided. The apparatus comprises a housing having at least one groove therein; and a knife moveable between retracted and extended positions, and positioned within the housing such that the knife passes through the groove as it is moved from the retracted position to the extended position, thereby cutting a suture positioned within the groove. A suture retainer for preventing a suture from escaping the groove prior to the cutting step is also provided. A method of cutting a pair of suture tails extending from a knot is also provided.

1. Field of the Invention
This invention relates to a suture cutter, as well as a method of cutting a pair of suture tails using this suture cutter. More particularly, the present invention provides a suture cutter which may be employed to safely cut one or more suture tails which are positioned at a location which is not easily accessible to traditional suture cutting means.
2. Description of Related Art
The majority of surgical procedures rely upon various types of sutures for not only closing incisions, but also for connecting and/or supporting structures within the body. The use of sutures also usually requires the tying of one or more knots in order to secure the suture in place. After these knots are tied, the pair of suture tails extending from the knot normally must be cut. If the tails are cut too short or unevenly, the knot may become untied. Alternatively, if the tails are left too long, the suture tails may be irritating to the patient or become entangled with other structures.
The cutting of suture tails can often be accomplished merely by employing surgical scissors, particularly when the knot is located outside of the patient's body. Many times, however, the knot and accompanying suture tails are located within the patient's body, or within an orifice of the patient's body. For example, sutures may be tied within the abdomen of a patient during a surgical procedure. In these instances, it may be difficult for medical personnel to safely employ standard surgical scissors to cut the sutures after tying. Thus, various types of suture-cutting devices have been developed which enable the medical personnel to cut the sutures in a location which normally would not be accessible to a pair of conventional scissors. These devices of the prior art suffer from many drawbacks, however, including the risk of the cutting blade inadvertently injuring the patient or physician. In addition, vision is often impaired during these procedures, and thus it can be difficult for the medical personnel to insure that the suture tails are left at the proper length. Most of these devices are also unable to simultaneously cut both tails.
One particular surgical procedure where cutting suture tails can be problematic is laparoscopic urethropexy for treating stress urinary incontinence in women. This procedure is described in U.S. patent application Ser. No. 08/519,606, which is herein incorporated by reference. In this procedure, one or more bone anchors are laparoscopically secured to the pubic bone of the patient, preferably adjacent to the space of Retzius. A suture extends from each anchor, and is preferably looped through an aperture in the anchor such that a pair of suture tails extend from the anchor. The suture tails are then pulled into the vagina, preferably by a suture-retrieving device which passes through the vaginal mucosa and enters the abdominal cavity to grasp the suture tails. The suture tails are brought through the entire thickness of the periurethral fascia and vaginal mucosa such that each tail penetrates the tissue at a predetermined distance from the other tail, and from the urethra. These tails may then be tied to one another in order to elevate the urethra and thereby eliminate the incontinence.
Once the suture tails are tied to one another within the vagina, the tails must be cut. If the tails are cut too close to the knot or unevenly, the knot is likely to become untied, thereby eliminating the correction provided by the surgery. If the tails are left too long, on the other hand, the excess suture material will cause irritation to the patient and may not be fully epithelialized. Properly cutting the suture tails within the vagina can be difficult, however, due not only to the confined space, but also due to the lack of operative vision. Surgical scissors and the like may not only cut the tails at an improper or uneven length, but may also damage vaginal tissue during the process. It is also difficult to simultaneously cut more than one suture tail with conventional scissors.
The present invention offers a unique suture cutter designed to easily cut sutures located within a body cavity or orifice. This suture cutter is particularly suited for simultaneously cutting suture tails to their proper length during the above-described laparoscopic urethropexy procedure.


The present invention is an imaged photographic element having a protective overcoat thereon. The protective overcoat formed by the steps of providing a photographic element having at least one silver halide light-sensitive emulsion layer; applying a coating comprising hydrophobic polymer particles having an average size of 0.01 to 1 microns, a melting temperature of from 55.degree. to 200.degree. C. at a weight percent of 30 to 95, and gelatin at a weight percent of 5 to 70 over the at least one silver halide light-sensitive emulsion layer. The silver halide light sensitive emulsion layer is developed to provide an imaged photographic element. The hydrophobic polymer particles are then fused to form a protective overcoat. In an alternate embodiment the coating further includes water soluble polymer materials at a weight percent of from 5 to 45.

Silver halide photographic elements contain light sensitive silver halide in a hydrophilic emulsion. An image is formed in the element by exposing the silver halide to light, or to other actinic radiation, and developing the exposed silver halide to reduce it to elemental silver.
In color photographic elements a dye image is formed as a consequence of silver halide development by one of several different processes. The most common is to allow a by-product of silver halide development, oxidized silver halide developing agent, to react with a dye forming compound called a coupler. The silver and unreacted silver halide are then removed from the photographic element, leaving a dye image.
In either case, formation of the image commonly involves liquid processing with aqueous solutions that must penetrate the surface of the element to come into contact with silver halide and coupler. Thus, gelatin, and similar natural or synthetic hydrophilic polymers, have proven to be the binders of choice for silver halide photographic elements. Unfortunately, when gelatin, and similar polymers, are formulated so as to facilitate contact between the silver halide crystal and aqueous processing solutions, they are not as tough and mar-resistant as would be desired for something that is handled in the way that an imaged photographic element may be handled. Thus, the imaged element can be easily marked by fingerprints, it can be scratched or torn and it can swell or otherwise deform when it is contacted with liquids.
There have been attempts over the years to provide protective layers for gelatin based photographic systems that will protect the images from damages by water or aqueous solutions. U.S. Pat. No. 2,173,480 describes a method of applying a colloidal suspension to moist film as the last step of photographic processing before drying. A series of patents describes methods of solvent coating a protective layer on the image after photographic processing is completed and are described in U.S. Pat. Nos. 2,259,009, 2,331,746, 2,798,004, 3,113,867, 3,190,197, 3,415,670 and 3,733,293. The application of UV-polymerizable monomers and oligomers on processed image followed by radiation exposure to form crosslinked protective layer is described U.S. Pat. Nos. 4,092,173, 4,171,979, 4,333,998 and 4,426,431. One drawback for the solvent coating method and the radiation cure method is the health and environmental concern of those chemicals to the coating operator. U.S. Pat. Nos. 3,397,980, 3,697,277 and 4,999,266 describe methods of laminating polymeric sheet film on the processed image as the protective layer. U.S. Pat. No. 5,447,832 describes the use of a protective layer containing mixture of high and low Tg latices as the water-resistance layer to preserve the antistat property of the V.sub.2 O.sub.5 layer through photographic processing. This protective layer is not applicable to the image formation layers since it will detrimentally inhibit the photographic processing. U.S. Pat. No. 2,706,686 describes the formation of a lacquer finish for photographic emulsions, with the aim of providing water- and fingerprint-resistance by coating the emulsion, prior to exposure, with a porous layer that has a high degree of water permeability to the processing solutions. After processing, the lacquer layer is fused and coalesced into a continuous, impervious coating. The porous layer is achieved by coating a mixture of a lacquer and a solid removable extender (ammonium carbonate), and removing the extender by sublimation or dissolution during processing. The overcoat as described is coated as a suspension in an organic solvent, and thus is not desirable for large-scale application. U.S. Pat. No. 3,443,946 provides a roughened (matte) scratch-protective layer, but not a water-impermeable one. U.S. Pat. No. 3,502,501 provides protection against mechanical damage only; the layer in question contains a majority of hydrophilic polymeric materials, and must be permeable to water in order to maintain processability. U.S. Pat. No. 5,179,147 likewise provides a layer that is not water-protective.
There remains a need for an aqueous coatable, water-resistant protective overcoat that can be incorporated into the photographic product, allows for appropriate diffusion of photographic processing solutions, and does not require coating operation after exposure and processing.

Water-resistant protective overcoat for AgX photographic system


A distributed data storage system that includes endpoint nodes, gateway nodes, and one or more gateway name servers. A gateway name server receives from clients resolution requests to resolve to a gateway node and resolves the resolution requests to a gateway node address of a gateway node. A gateway node receives client requests to access an endpoint node and redirects the requests to endpoint nodes identified by a gateway node whose address was resolved to by a gateway name server. An endpoint node receives from a client a retrieval request to retrieve data based on being redirected to the endpoint node. When a retrieval request is received and the endpoint node stores the data, the endpoint node sends the data to the client. When a retrieval request is received and the endpoint node does not store the data, the endpoint node forwards the retrieval request to another endpoint node.

The modern computing world is increasingly moving from organizations storing their electronic data on their own computer equipment to storing data and performing computations on computers owned by data center operators referred to as cloud computing. Cloud computing is growing rapidly and dominated by a limited number of large companies. Although these companies are generally reliable as centralized entities, they present a single point of failure for any company that relies on their services. The centralization of these computing resources also presents other potential exploits with undesirable outcomes for most stakeholders. For example, a server in a data center may be infected with ransomware (e.g., a type of malware) that exploits a security flaw in the supervisory software that provides overall control of the data center. The ransomware may propagate to other servers and encrypt data that is accessible to those servers using an encryption key. The encrypted data cannot be used by the server until a ransom is paid in exchange for a decryption key that can be used to decrypt the encrypted data.
One approach to removing the single point of failure presented by centralized cloud computing data repositories is decentralized data storage. Decentralized data storage stores data on different computers distributed across geographic areas and organizations so that no one entity presents a single point of control either for the availability of data or for the integrity of their contents. One open source software project that has sought to provide decentralized data storage is the Inter-Planetary File System (IPFS).
Although IPFS is considered by many to be an improvement over prior decentralized data storage, implementations of IPFS have had problems. One problem is that access times are unpredictable because an access request may be routed to indeterminable number of data storage servers. Another problem is the inability to provide asynchronous forward replication of data to ensure data availability against failures.


A TDMA RF received signal is demodulated by first being filtered with a fixed transversal filter having a characteristic selected for matching a fixed square root raised cosine pulse characteristic of the received signal. The filtered signal is then adaptively filtered for compensating for a time varying impulse response of the channel. The adaptive filtering is performed initially during a synchronizing portion (preamble) of the filtered signal in accordance with a fast recursive least squares algorithm. Subsequent filter adaptation to a data portion of the filtered signal is accomplished in accordance with a computationally less expensive normalized least mean square procedure. The adaptive filter repetitively applies a modified Viterbi algorithm to blocks of 2D symbols, such that D symbols are released for adapting the adaptive filter means during the data portion of the filtered signal and the signal. The released symbols are also employed for adapting elements required in computing a metric for the modified Viterbi algorithm and the reconstructed signal used to form an error signal that drives the adaptation algorithms.

A requirement for increased capacity in the U.S. cellular radio system has resulted in adoption of digital technology. The digital system employs time division multiple access (TDMA) as a channel access method in conjunction with a digital modulation scheme. A proposed standard (IS-54) for digital cellular communication specifies a particular frame and slot structure. Under this standard, three to six users share a common 30 KHz radio frequency (RF) channel. Each user transmits data in an assigned time slot which is part of a larger frame. The gross bit rate of data transmitted over the channel is 48.6 Kbits/sec. The transmitted digital data is first mapped onto pi/4-shifted differentially encoded quadrature phase shift keying (DQPSK) symbols and then pulse shaped using a square root raised cosine filter. The pulse shaped signal is subsequently modulated onto an RF carrier.
Data transmission in this digital cellular system is adversely affected by multipath propagation which causes delay spread and consequent inter-symbol interference (ISI), where a symbol is comprised of a pair of binary bits. Delay spread is expressed in terms of a quantity called delay interval, which is measured as the time interval between the first ray and last significant ray arriving at the receiver. Delay spreads exceeding one third of the symbol duration cause a significant increase in bit error rate (BER), necessitating use of an equalizer in the receiver. Typical delay spreads encountered in urban and rural areas in the U.S. are less than 40 microseconds, implying a need for equalization of one symbol of interference (40 microseconds) for a data rate of 48.6 Kbits/sec. Mobile receivers also experience rapid channel variations and Doppler induced frequency shifts that are proportional to vehicle speed.
The channel impairments described above require that nonlinear adaptive equalizers be incorporated in cellular radios. Two suitable equalizers are the decision feedback equalizer (DFE) and an equalizer based on a maximum likelihood sequence estimator (MLSE). The MLSE method employs the well known Viterbi algorithm and is referred to in the art as a Viterbi equalizer or an MLSE-VA equalizer.
Both the MLSE and DFE techniques have been researched in some detail for the European CEPT/GSM cellular radio system. Results of this research are reported by, for example, R. D'Avella et al. "An Adaptive MLSE Receiver for TDMA Digital Mobile Radio", IEEE Journal on Selected Areas in Communications, Vol. 7, No. 1, pp. 122-129, Jan. 1989, G. D'Aria et al. "Design and Performance of Synchronization Techniques and Viterbi Adaptive Equalizers for Narrowband TDMA Mobile Radio", proceedings of 3rd Nordic Seminar on Digital Land Mobile Radio Comm., Copenhagen, Denmark, Sep. 13-15, 1988 and A. Baier et al., "Bit Synchronization and Timing Sensitivity in Adaptive Viterbi Equalizers for Narrowband TDMA Digital Mobile Radio Systems", proceedings of IEEE Vehicular Technology Conference, Philadelphia, pp. 377-384, 1988.
The CEPT/GSM system, however, is quite different from the system proposed for the U.S. in that it employs a narrower time slot, partial response modulation Gaussian Minimum Shift Keying (GMSK), a wider bandwidth (200 KHz) and a higher data rate (270.8 Kbits/sec.). The narrower time slot typically permits the channel to be treated as being time invariant while the wider bandwidth implies a reduced fade depth. The higher data rate results in increased ISI. As a result, the channel equalization requirements of the European and the proposed U.S. cellular systems are different.
A fractionally spaced DFE (FS-DFE) technique is disclosed by the present inventors S. Chennakeshu, A. Narasimhan and J. B. Anderson in copending and commonly assigned U.S. patent application Ser. No. 07/754.105, filed Sep. 3, 1991, entitled "Decision Feedback Equalization for Digital Cellular Radio". This DFE technique employs a complex fast Kalman algorithm to track channel variations. The fast Kalman algorithm described therein is an extension of a type taught by D. Falconer et al. in "Application of Fast Kalman Estimation to Adaptive Equalization", IEEE Trans. Comm., Vol. COM-26, No. 10, pp. 1439-1446, Oct. 1978. The extensions provide for the use of a complex form without matrix inversions and stabilization of the algorithm, for finite precision implementation, through the addition of appropriate dither signals.
An alternative technique employs an equalizer based on a lattice structure and is disclosed by the present inventors S. Chennakeshu, A. Narasimhan and J. B. Anderson in copending and commonly assigned U.S. patent application Ser. No. 07/753,579, filed Sep. 3, 1991, entitled "Order Recursive Lattice Decision Feedback Equalization For Digital Cellular Radio". This DFE method employs a least squares (LS) adaptive algorithm to achieve convergence and tracking properties similar to that of the complex fast Kalman algorithm.
Another technique achieves equalization through MLSE demodulation. There are two fundamental approaches to realizing a MLSE demodulator. One of these approaches is described by G. D. Forney in "Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence of Intersymbol Interference", IEEE Trans. Info. Theory, Vol. IT18, pp. 363-378, May 1972. Forney's approach uses a Viterbi algorithm to realize the maximum likelihood sequence estimator, with a squared metric that is derived based on the assumption that the additive noise in the received signal, at the input of the maximum likelihood sequence estimator, is white and Guassian. This is accomplished through use of a whitening filter at the input of the maximum likelihood sequence estimator.
The other MLSE approach is described by Gottfried Ungerboeck in "Adaptive Maximum Likelihood Receiver for Carrier Modulated Data Transmission Systems", IEEE Trans. Comm., Vol. COM22, No. 5, pp. 624-636, May 1974. This MLSE approach employs a matched filter followed by a MLSE algorithm and an auxiliary channel estimation scheme.
The technique of Ungerboeck is currently favored, primarily to circumvent stability problems associated with use of the whitening filter. The Ungerboeck MLSE demodulator includes a transversal filter to approximate a matched filter, use of the Viterbi algorithm to implement the MLSE and a set of LMS or gradient algorithms to perform adaptation functions for the channel estimation. Differences in design of the matched filter and channel estimation algorithm account for range complexity and performance differences in various implementations of this demodulator. The equalization approach used in the CEPT/GSM system (as described by R. D'Avella et al. in "An Adaptive MLSE Receiver for TDMA Digital Mobile Radio", IEEE Journal on Selected Areas in Communications, Vol. 7, No. 1, pp. 122-129, January 1989) is similar to Ungerboeck's approach, except that the initial estimate of the channel impulse response is acquired through a correlation based search.
As was previously stated, however, the significant differences between the CEPT/GSM and the proposed U.S. digital cellular systems preclude the adaptation, without significant and non-trivial modification, of the CEPT/GSM equalization technique in the U.S.
It is thus an object of the invention to provide an adaptive MLSE-VA receiver for a digital cellular radio system that is suitable for use with the proposed U.S. cellular signalling standard.

Adaptive MLSE-VA receiver for digital cellular radio


Pharmaceutical compositions for the topical treatment of androgen-related conditions, e.g., acne in humans containing an amount of the compound represented by formula II effective for the topical treatment of the androgen-related conditions, e.g., acne ##STR1## dissolved in an alcohol-water solvent system, such as ethanol-water 97.6:2.4(w/w)! and having an apparent pH in the range of about 3.5 to 4.5, and containing a gelling agent are disclosed.

This invention relates to stable pharmaceutical compositions in the form of a gel which are suitable for treating acne and other androgen-related conditions, including seborrhea, hirsutism, and androgenic alopecia, in humans and which contain an antiandrogen compound dissolved or suspended in an alcohol-water solvent system and having an apparent pH value of no more than about 5 and a gelling agent
International Publication No. WO 94126767, published Nov. 24, 1994 discloses antiandrogens represented by the formula I ##STR2## wherein n is an integer of 2 to 3, pharmaceutical compositions containing such antiandrogens and methods of using such antiandrogens to treat androgen-dependent diseases including acne.
In the course of development of a pharmaceutical composition containing one of the antiandrogenic compounds of formula I, it was discovered that this compound is unstable and decomposes over time even at 25.degree. C.
Thus, there is a need for a stable pharmaceutical composition containing an antiandrogen useful for topical treatment of androgen-dependent diseases including acne and having an extended shelf life suitable for commercial use.


A drive apparatus for a hybrid vehicle equipped with an engine and a motor, heats the engine or a catalytic converter using the regenerated electricity of the motor. As the temperature of the engine or the catalyst thus rises, air polluting components in an exhaust gas discharged via the motor or the catalyst converter are reduced. Typical air polluting components are NC, NOx and CO.

1. Field of the Invention:
This invention relates to a drive apparatus for a hybrid vehicle having an engine and a driving motor, and more particularly to the treatment of exhaust gas produced when the engine is activated.
2. Description of the Related Art:
In recent years, for the purposes of air environment protection and noise reduction, a so-called electric vehicle equipped with an electric motor as a drive source has commanded a lot of attention. However, a battery to activate the electric motor has only a limited capacity so that the electric vehicle can travel only a limited distance on one battery charging, compared to gasoline vehicles. Further, unlike filling up with gasoline, it takes a long time to charge up the battery of the electric vehicle so that it is impossible to increase uninterrupted mileage to a considerable extent.
To this end, a hybrid vehicle has been proposed which suppresses the exhaust gas and noise problems of the conventional gasoline vehicles and complements the disadvantage of the electric vehicles. In this hybrid vehicle, a generator is activated by the engine to supply electricity to a motor for driving the vehicle and also to accumulate electricity in a battery. In the hybrid vehicle, like the conventional electric vehicle, the battery can supply electricity to the motor for driving the vehicle. Further, since variance in output torque can be damped by the battery, it is possible to operate the engine in a constant condition, irrespective of the travelling conditions of the vehicle. It is therefore possible to operate the engine so as to cause less noise and less noxious substances to be contained in the exhaust gas.
FIG. 5 of the accompanying drawings shows, of the prior hybrid vehicles, a so-called series hybrid vehicle. The series hybrid vehicle comprises an engine 1 to be driven by fuel such as gasoline, a generator 2 to be activated by the engine 1 to generate d.c. electricity, a battery 3 for accumulating the electricity generated by the generator 2, an inverter 4 for converting the d.c. electricity from the generator 2 and the battery 3 into a needed value of a.c. electricity, an induction motor 6 to be activated by the a.c. electricity from the inverter 4, and a transmission or gearbox 7 for transmitting the driving force of the motor 6 to tires 8.
During power running, fuel such as gasoline is supplied to the engine 1 for rotation at a predetermined r.p.m. The torque of the engine 1 is transmitted to the generator 2 for conversion into d.c. electricity. Of the thus obtained electricity, an amount sufficient to drive the motor 6 is sent to the motor 6 via the inverter 4 and the surplus electricity is accumulated in the battery 3. On the other hand, the torque of the motor 6 is transmitted to the tires 8 via the transmission 7 to cause the hybrid vehicle to travel. When the electricity sent to the motor 6 from the generator 2 is short, the battery 3 supplies the shortage. The supply of electricity to the motor 6 is varied by controlling a built-in switching device of the inverter 4 to react accordingly to the extent of stepping on the accelerator or gas pedal.
On the other hand, to lower the speed of the hybrid vehicle, regenerative braking is used as a counterpart to engine braking. Regenerative braking is performed as the switching device built into the inverter 4 is controlled. During this regeneration, rotational energy is given to the motor 6 from the tires 8 via the transmission 7. Regenerated electricity is produced from the motor 6. This regenerated electricity is converted into d.c. electricity by the inverter 4, and is then accumulated in the battery 3.
As mentioned above, the hybrid vehicle carries the engine 1. Whenever the engine 1 is operated, it produces exhaust gas; consequently the most important subject currently is to realize low environmental pollution by minimizing air polluting substances in the exhaust gas.
The emission of air polluting substances in the exhaust varies sharply as the operating condition of the engine 1 is changed. For example, if the engine 1 is started at the beginning of operation when it is low in temperature (cold starting), the emission of air polluting substances is increased very much. Usually the vehicle is equipped with an exhaust gas cleaner called a catalytic converter; if this catalytic converter works adequately, the exhaust gas contains only a very small amount of air polluting substances. If it is low in temperature, however, the catalytic converter works inadequately so that the emission of air polluting substances such as hydrocarbon (HC) is increased. Thus if an engine-related part or element, such as the engine body or the catalytic converter, is low in temperature, air polluting substances in the exhaust gas are increased.
Japanese Utility Model Publication No. SHO 56-17724 discloses a concept of warming up the engine using the electricity from the battery. In this prior art, since a heater dedicated for warming-up is used, it is impossible to use regenerated electricity efficiently.


Provided is a portable communication device including a first housing, a second housing rotatably coupled with the first housing, and a hinge portion provided between the first housing and the second housing to stepwise rotate the second housing toward or away from the first housing, in which display units are disposed on inner and outer sides of the first housing and the second housing, respectively, such that the display units on the inner and outer surfaces of the housings may be used independently or in conjunction to provide for larger display screens.

1. Field of the Invention
The present invention relates to the field of portable devices and more particularly to a hinged operated portable device including a plurality of display units.
2. Description of the Related Art
Generally, "portable communication devices" as the term is used herein refers to devices that allow for a form of communication, while the devices are being carried. Various applications or types of communications may be performed by the portable device. For example, voice communication, short message service, mobile banking, television (TV) watching, on-line game service, and on-demand video service are communications or applications that may be provided to users using portable communication devices.
The portable communication devices may include devices such as a hand-held phone (HHP), a cordless telephone (CT-)2 cellular phone, a digital phone, a personal communications systems (PCS) phone, and a personal digital assistant (PDA) and are sorted into various types according to their appearances. For example, wireless terminals are sorted into a bar type, a flip type, a folder type, a sliding type, and a pop-up type according to their appearances. The above-mentioned portable communication devices always include an antenna apparatus, a data input/output device, and a data transceiver. For the data output device, a display unit is generally used. Recently, some terminals include a touch screen that allow the user to input data by touching a display screen on the display unit
However, a display unit of a conventional portable communication device generally has a screen size of about 320×240 pixels, and such a small screen size of the display unit is too small for a user to comfortably access a public network, such as the Internet, or watch television or operate an on-line game service, or watch a multimedia presentation (e.g., moving or motion pictures)
In addition, the conventional portable communication device needs a separate cradling device that may hold the device in place. Generally, the cradling device allows the user to position the portable device at an angle convenient for viewing. Otherwise, it is inconvenient for the user to see the (display) screen of the display unit that is placed on a desk without a cradling device.
As a result, there is a need for a portable communication device in which a plurality of display units may be used together or positioned to allow convenient viewing of the display screen.

Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do


A carrier is formed with a circular cylindrical supporting part 4a. This supporting part 4a is formed with a receiving hole 4b. A planetary gear 5 is rotatably received in the receiving hole 4. One side part inner peripheral surface and the other side part inner peripheral surface of the receiving hole 4a in the peripheral direction of the supporting part 4a are each formed of a circular arcuate face having a same radius of curvature as the radius of the planetary gear 5. The centers of curvature of the circular arcuate faces forming the one side part inner peripheral surface and the other side part inner peripheral surface, respectively, are spacedly arranged from each other in the peripheral direction of the supporting part 4a. Owing to this arrangement, the interval between the one side part inner peripheral surface and the other side part inner peripheral surface of the receiving hole 4a can be made larger by a portion equal to the distance between the centers of curvature than the outside diameter of the planetary gear.

In general, a differential gear apparatus for vehicles includes a plurality of planetary gears which can rotate and revolve. Each planetary gear is rotatably (about its own axis) received in a receiving hole formed in a carrier (see Official Gazettes of Japanese Patent Application Laid-Open Nos. H04-312247, H09-112657 and 2002-89659).
Since the planetary gear rotates about its own axis, its outer peripheral surface slide-contacts the inner peripheral surface of the receiving hole. Moreover, the end face of the planetary gear slide-contacts the bottom surface of the receiving hole or a member for axially supporting the planetary gear. Owing to this arrangement, in the conventional differential gear apparatus, there is such a problem that the planetary gear is easily worn out early.
One example of such a problem will now be described in more detail. FIG. 4 is a sectional view showing a state in which a planetary gear P is received in a receiving hole Q1 of a carrier Q. The inside diameter of the receiving hole Q1 is set to be larger than the outside diameter of the planetary gear P so that the planetary gear P can rotate about its own axis and a lubricant can be received between the inner peripheral surface of the receiving hole Q1 and the outer peripheral surface of the planetary gear P. When the outer peripheral surface of the planetary gear P is pressed against the inner peripheral surface of the receiving hole Q1, in a case wherein the inside diameter of the receiving hole Q1 is set to be larger than the outside diameter of the planetary gear Q, the contact area between the inner peripheral surface of the receiving hole Q1 and the outer peripheral surface of the planetary gear P is reduced compared with a case wherein the inside diameter of the receiving hole Q1 is set to be equal to the outside diameter of the planetary gear P. For this reason, the outer peripheral surface of the planetary gear P is easily worn out early.


A personal information manager or other software program, preferably residing within a palmtop computer, uses a time of day profile to establish a default data category. When the user wishes to enter or edit data or retrieve data, the personal information manager or other software program inspects a real-time clock to determine the time of day. The personal information manager or other software program then establishes a default category based upon the time of day profile established by the user. The user is given the opportunity to modify the default category at any time. In this manner, for example, the user can establish a default business category during business times in days and a personal category during personal times in days. This provides the advantage of correctly categorizing data in an automated manner under most circumstances.

As the components required to build a computer system have reduced in size, new categories of computer systems have emerged. One of the new categories of computer systems is the "palmtop" computer system. A palmtop computer system is a computer that is small enough to be held in the hand of a user and can be "palm-sized." Most palmtop computer systems are used to implement various Personal Information Management (PIM) applications such as an address book, a daily organizer, a to-do list and an electronic notepad, to name a few.
Palmtop computer users generally use their palmtop computers for both business and personal use. As such, various functions carried out by the palmtop computer (e.g. PIM functions) serve both business and personal purposes. For example, a calendar management program used as a daily organizer may serve to provide records of appointments for both personal and business use. Similarly, an address book can carry both business contacts and personal contacts, and a to-do list can have personal tasks as well as business tasks. The palmtop computer user can currently segregate some of these tasks by designating a category at the time of entry, and at the time of retrieval, selectively retrieve only certain categories. But, the additional steps involved in categorizing entries and data being retrieved is often too cumbersome to encourage the user to fully utilize the palmtop computer's categorization features. Thus, entries are often left uncategorized and retrieval of data generally is done globally to retrieve all entries without bothering to look only for a particular category. As a result, the calendar viewed is typically filled with both personal and business appointments, all entries are generally viewed in the address book and a mixed business/personal to-do list is generally viewed. Identifying the data of interest can thus be encumbered with irrelevant data.

Time based profile management on palmtop computer


The present invention discloses a method for estimating DOA of a terminal in multiple co-frequency cells, including the steps of: A. obtaining a channel estimation result of at least one terminal expecting a calculation of DOA in an expecting co-frequency cell; B. performing a Direction-of-Arrival estimation for the expecting terminal in the expecting cell based on the channel estimation result through a DOA estimating method with a wave beam scan, a DOA estimating method with a maximum power path, or a DOA estimating method with a primary eigenvector. With the channel estimations of the multiple cells in the invention, accurate channel estimation results of the respective cells may be provided, from which the channel estimation result of the expecting terminal is selected.

In a Code Division Multiple Access (CDMA) mobile communication system, signals of multiple users are overlapped in the time and frequency domains, and the signals of the respective users upon reception have to be separated from each other with a signal separation method in the digital domain. In the case of co-frequency networking, there is serious multiple-access interference and intersymbol interference, and there is also relatively strong mutual interference between signals of co-frequency neighbor cells. In the prior art, a joint detection technology is used to eliminate the multiple-access interference and the intersymbol interference, in which the co-frequency interference is treated simply as part of background noise.
For a slot CDMA system using array antennas, since information provided from an interference signals of a co-frequency neighbor cell is not available, the co-frequency interference is treated simply as part of the background noise, thus a Direction-of-Arrival (DOA) estimation only for the local cell, i.e. a DOA estimation for a single cell at a single base station, can be performed, and DOA estimations for multiple co-frequency cells at a single base station can not be performed.

Method for estimating direction-of-arrival of terminal in multiple co-frequency cells

Shanghai Ultimate Power Communications Technology Co., Ltd.