Abstract: System and method for optimally updating a neighbor set for use by a mobile unit during soft handoff of the mobile unit in a CDMA cellular telephone environment is disclosed. A two-step process is used to ensure that the individual neighbor sets of active set members are combined in a manner such that only pilots representing the more important sectors are included in the updated neighbor set and pilots representing the less important sectors are excluded therefrom. In the first step, active set members whose RTD is more than twice as great as an OWD threshold are eliminated from consideration. In the second step, the neighbor set of the mobile unit is updated using the sectors included in the individual neighbor sets of the active set members that were not excluded by the first step, wherein those sectors are included in the updated neighbor set according to the number of individual sets in which they are found and their priority within those sets.

Abstract: A mean optical power controller that controls power using a voltage controlled optical attenuator (VCOA) is disclosed. This controller uses a control loop in which a signal indicative of the present optical power level is compared to a signal indicative of the desired optical power level, with the difference then being used as input into the VCOA. This controller generates the required variety of signals indicative of the desired optical power level, or reference signals, without having to rely on a CPU. It does this by storing in a local storage means the voltage-values of the reference signals required to realize each supported user-defined optical power level. During the operation of the controller, the voltage-value corresponding to each selected power-level is passed to one or more DACs, where it is converted into a reference signal.

Abstract: A method and apparatus for notifying a user of a call waiting while a telephone is on hold. A transmit signal path and a receive path between a central office line and transmitter and receiver elements in the telephone are muted to place a call on hold. A customer premise equipment alerting signal is received from the central office while the transmit signal path and receive path are muted. The receive path is un-muted after the customer premise equipment alerting signal is received and an audible message signal is generated and inserted into the receive path in response to the customer premise equipment alerting signal to notify a user that the customer premise equipment alerting signal has been received. The receive path is then re-muted.

Abstract: The present invention relates to a device for both-way transposition between optical signals and electrical signals, for a communications system, said device comprising a vertically integrated component comprising an optically driven oscillator based on a negative differential conductance mechanism, for performing optical-to-millimetric conversion on the down path, and an asymmetric Fabry-Perot cavity modulator for performing the electrical-to-optical conversion function on the up path.

Abstract: This network, intended for the transmission of information in optical form, wavelength multiplexed, comprises nodes (N1, N2) linked to each other by at least one optical fiber (F1), at least one wavelength being treated in each node. The system comprises unit (OF1, OF2, OS1, OS2) for superimposing on the information, for at least one wavelength per node, a surveillance signal whose frequency is outside the transmission band and, in each node, a surveillance circuit (CS1, CS2) for sampling at least one part of the surveillance signals, elaborating surveillance information in function of this part and sending this information to the processing units of the network. Application in optical telecommunications.

Abstract: An apparatus for interfacing a data processing system with n.times.N number of data communications network(s) includes N number of interface units, a pair of control units, and linking units, both n and N being positive integer, respectively. The interface units coordinate a data exchange between the data communications network(s) and the control unit in response to control signals, wherein each interface unit includes n communications ports. Each in the pair of control units generates the control signals and coordinates a data exchange between the data processing system and the interfacing units, wherein each control unit is identical to each other, operates alternately in active/stand-by mode and shares data by using a path therebetween. The linking unit is for use in exchanging data between the data processing system and the control units, between the control units and the interfacing units, and between the interfacing units and the data communications network(s).

Abstract: In a switched telecommunication network (PSTN or ISDN) between a calling party connected to an ISDN switched digital network and a destination called party whose call number is written "Z", the number "Z" of the destination called party is automatically replaced by a number "Y" for an intermediate site which is connected to the ISDN, and the number "Z" of the destination called party is conveyed to the intermediate site, via the ISDN D channel. This substitution process is extended to interconnections between competing ISDN networks and creates a new kind of signaling for use between public exchanges, intermediate between protocol D and ITU-T semaphore channel number 7.

Abstract: A content addressable memory employs a word-sliced architecture, in order to localize word match logic, and a global data bus, to convey data between the memory input/output circuitry and the plurality of word slices. Timing information is embedded in the global data bus in the form of a model global data signal. This signal interacts with two major control signals to self-time the memory. The number of major control signals is such that all possible memory states are uniquely represented, but the memory cannot power-up in an invalid or unrecoverable state. Three model timing paths are used to match the delay of the self-timing loop with that of the actual operation: one each for READ, WRITE and SEARCH.

Abstract: The present invention provides a layered antenna (otherwise known as a flat-plate antenna) having a number of radiating elements (201), each radiating element comprising a first substantially rectilinear aperture (210), having a first pair of oppositely directed probes (220,222) extending into an area defined by the aperture with secondary apertures (212,214) arranged coextensive with and on opposite sides of the primary aperture, adjacent said first pair of probes, said secondary apertures operable to modify the beamwidth in a plane coextensive with said first pair of probes. There is also provided a method of receiving and transmitting signals by means of a layered antenna of this construction.

Abstract: A process of transferring a message transferred by a TTY call from a calling party to a called party comprising the following steps: (a) receiving the TTY call in a port adapted to receive the TTY call; (b) recognizing the TTY call as conforming to TTY standards and translating the TTY call to ASCII; (c) initiating a request for the calling party provide identification information to identify the called party and to leave a message and converting the request to conform to the TTY standards to create a converted response, and sending the converted response to the calling party, (d) receiving the identification information to identify the called party and the message, converting the identification information and the message to ASCII to create a converted message; identifying a voice mail box accessible by the called party with the identification information in a voice mail system; (e) converting the message into an audio message; and storing the audio message in the voice mail box.

Abstract: In methods and apparatus for computing measures of echo of a far end signal in a near end signal, the evolution over time of frequency spectra of the near end and far end signals are compared to compute a measure of the echo. A far end spectrum of the far end signal and a near end spectrum of the near end signal are determined for each of a plurality of successive time intervals. A respective measure of correlation is determined for each of a plurality of spectrum pairs, each spectrum pair comprising a respective near end spectrum and a respective far end spectrum, the far end spectrum corresponding to a time interval which lags a time interval corresponding to the near end spectrum by a respective time lag. The measures of correlation are compared to determine a maximum measure of correlation which can be used as a measure of echo. The echo measure computation technique is particularly suitable for use in echo suppressors for digital cellular telephony systems, but has other applications.

Abstract: In an ATM network a flexible AAL1 processor is connected to a similar AAL1 processor by a virtual circuit. This virtual circuit has n.times.64 kb/s capacity wherein each 64 kb/s channel or a P.times.64 kb/s subset of the capacity can be used for a separate call. The virtual circuit behaves similarly to trunk groups within present day digital networks and it is therefore termed a Virtual Trunk Group. Many Virtual Trunk Groups can be connected between the same two endpoints and contained within a virtual path thus forming a Virtual Route. The network is provided with a mechanism which allows the n.times.64 kb/s capacity to be changed by a managed process which ensures that established calls are not affected by the change of capacity. This change of capacity is performed in such a way that the clock systems of the two AAL1 processors are able to behave in the normal manner for synchronised or plesiochronous switching networks without incurring additional frame slips in the AAL1 data stream.

Abstract: In methods and apparatus for providing communications to a telecommunications terminal, a request for a page of data is received at a data service node, the request specifying at least one particular terminal. A terminal status request is sent from the data service node to a communications system which serves the particular terminal, the terminal status request specifying the particular terminal. The data service node receives from the communications system a terminal status message containing information indicating a current status of the particular terminal. The data service node sends to the data terminal a page of data indicating the current status of the particular terminal. The page of data comprises a communications request icon when the particular terminal is in a state in which it can communications.

Abstract: A system facilitates use of a corporate dialing plan by authorized remote callers. The system includes a receiving element, a sending element, a detecting element, and an establishing element. The receiving element receives a telephone call signal and a telephone number from a remote caller indicating a desire to use the corporate dialing plan for placing a telephone call to a called party using the telephone number. The sending element sends a telephone calling signal to the called party at the telephone number using the corporate dialing plan. The detecting element detects an answer signal from the called party in response to the sending element sending the telephone calling signal. The establishing element establishes a connection between the remote caller and the called party when the detecting element detects the answer signal.

Abstract: A method and apparatus in a communications system for tracking mobile stations. The length and identify of the path of the mobile station is tracked at the mobile station. The path is monitored for a presence of a loop. In response in identifying the presence of a loop, the loop is removed from the path, wherein the length of the path is reduced. Additionally, the length of the path is compared to a threshold and a location update is performed in response to the length of the path being greater than the threshold. The threshold may also be updated at a MSC and then sent to the mobile station.

Abstract: This camera comprises an electron tube with a photosensitive target (6) made of single-crystalline semiconducting material, lens (10) for forming the image of a scene on the target, an electron gun (14) to supply an electron beam to read the target, and scanning and focusing portion (18) designed to force the target to be scanned by this electron beam and to focus this electron beam on the target. The target then outputs a signal representative of this image. The camera also includes an electronic processing circuit (20) for controlling the electron gun and scanning and focusing of the camera and receiving and storing circuits (22) for receiving and storing the signal. Application to the analysis of very fast movements.

Abstract: A discrete phase shifter and a method for discrete phase shifting in which an input signal is split into two signals. One of the split signals is phase shifted by a first fixed amount by a first fixed phase shifter cell, and the other split signal is phase shifted by a second fixed amount by a second fixed phase shifter cell. A selector is utilized to select at least one of the two split phase shifted signals and to input these to a vector summer. The vector summer synthesizes an output signal that is phase shifted with respect to the input signal. In this manner, the output signal is discretely phase shifted either by the first fixed amount, the second fixed amount, or, by selecting both of the split signals prior to vector summing, the sum of these amounts.

Abstract: This invention relates to an integrating circuit and finds application in high time constant low bandwidth feedback loop arrangements, e.g. in phase locked loop circuits. A well-known form of integrator is the Miller integrator, as used in Phase Lock Loop circuits (PLL) which are frequently used in communication systems, and are employed, for example, in clock extraction circuits in optical fiber receivers. With the advent of Passive Optical Networks (PON) becoming a means of providing fiber to the home very accurate timing information is required, to allow the outstation optical transmitter to send data within its designated time slot. The timing source at the base station needs to have a narrow jitter bandwidth of no more than, typically, 0.1 Hz, which cannot be realized with known phase lock loop circuits. The present invention seeks to provide an improved integrator which allows the fabrication of such timing circuits using standard components.

Abstract: An electronic phase shifter splits an input signal into two signals whose amplitudes are set by a weighting circuit controlled by a phase shift control signal. Each of the two outputs of the weighting circuit is loaded with an RLC resonator, one tuned to a frequency lower than that of the input signal and one tuned to a frequency higher than that of the input signal. The loaded outputs are recombined in a vector summing network to synthesize the required phase shifted output signal. This technique permits implementation on a monolithic integrated circuit (MIC) with high gain at high frequencies (e.g. 10 GHz). It also allows a large dynamic range of operation and a large (i.e., greater than 90 degrees) controllable phase shift. This is accomplished without the use of variable reactance elements or any other components external to the MIC.