Abstract: The invention is a system for providing virtual connections through an ATM interworking multiplexer on a call-by-call basis. A signaling processor receives signaling for a call and selects the virtual connection for the call. The signaling processor generates control messages that identify the selection and transfers the control messages to the ATM interworking multiplexer that accepted the access connection for the call. The multiplexer converts user information from the access connection into ATM cells for transmission over the virtual connection in accord with the control messages.

Abstract: A resource reservation for a file transfer at an ingress node, core nodes, and an egress node on a file transfer route in a packet switching network is realized by sequentially carrying out a control processing for determining a reserved rate function rrsv(t) indicating an output bandwidth at each node as a function of time t according to an input rate function rin(t) indicating an input bandwidth at each node as a function of time t and a vacant rate function r&phgr;(t) indicating a vacant bandwidth at each node as a function of time t, and judging whether it is possible to accept the reservation request at each node or not according to whether a difference between the input rate function and the output rate function exceeds a buffer capacity available at each node or not.

Abstract: A format programmable hardware packetizer (110) receives real-time raw input data (125) from a multimedia data source (103) via an analog to digital converter (105) and a data encoder (120) gated by encoder interrupts (127). The real-time raw input data is buffered in an internal byte collector of the packetizer (110). A main CPU interrupt (117) is issued to the main processor (130) when a packet boundary code is received. The packetizer (110) formats the data according to a desired format selected on line (115) for dump to the main memory (140) while providing a managed, much lower level of interrupts to the main processor (130) on the CPU interrupt line (117). A plurality of hardware packetizers (110) can be deployed according to alternative constructions for efficient real time packetizing in various selected formats.

Abstract: A SONET/SDH architecture is disclosed that enables the multiplexing of STS-1's from different SONET/SDH rings into a single STS-N for transmission via a single optical fiber, but while maintaining the association of each of the STS-1's with its respective SONET/SDH ring. For example, when an STS-48 carries 12 STS-1's from a first SONET/SDH ring and 12 STS-1's from a second SONET/SDH ring, the STS-48 carries: the automatic protection switching channel for the 12 STS-1's from the first SONET/SDH ring (with addresses specified in the address space of the first SONET/SDH ring); and the automatic protection switching channel for the 12 STS-1's from the second SONET/SDH ring (with addresses specified in the address space of the second SONET/SDH ring).

Abstract: A modem for use in Digital Subscriber Line communications transmits and receives data over the local subscriber loop in common with voice information over the loop, while avoiding the need for voice/data splitters. The modem responds to disruptions associated with “disturbance events” such as on-hook to off-hook transitions and the like by rapidly switching between pre-stored channel parameter control sets defining communications over the loop under varying conditions. In addition to changing parameter control sets responsive to a disturbance event, the modem may also change transmission power levels and other system parameters such as frequency domain equalizer characteristics. Further, provisions are made for reduced bandwidth communications under selected conditions.

Abstract: A system for detecting collisions in a shared communications medium, such as a TDMA medium, includes a receive path adapted to generate a first intermediate signal, a second intermediate signal, and a data symbol sequence from an input signal. A preamble detection module generates a correlation metric from the first intermediate signal. A power measurement module generates a power indication signal from the second intermediate signal. A noise measurement module generates a noise indication signal from the second intermediate signal and the data symbol sequence. A processing module is adapted to characterize the input signal as a collision for certain values of correlation metric, power indication signal, and noise indication signal.

Abstract: Transmission system for the transmission of digital signals, present in the form of time-division multiplex channels, between an exchange termination (ET) and a line termination (LT). Both the exchange termination (ET) and the line termination (LT) is respectively connected to a user interface (UNI) of an ATM network (ATMN) via a means (IWF) for converting time-division multiplex data into ATM cells or, respectively, from ATM cells into time-division multiplex data, whereby a virtual ATM channel is allocated to each time-division multiplex channel using this means.

Abstract: A time division multiplex link is used with successive frames each having a specified number of transmission timeslots. A first unit inserts ATM cells into a part of the timeslots which is allotted to the ATM flow intended for a second unit and other data into other timeslots allotted to the transport of at least one non-ATM flow intended for a third unit. The signals received are analyzed so as to search for synchronization with the cells of the ATM flow and to identify that part of the timeslots which is allotted to the ATM flow. This analysis comprises a synchronization test executed successively on subsets of timeslots within the frames until good synchronization is observed. The cells extracted from the timeslots of the identified part are then directed to the second unit, while the other data are directed to the third unit.

Abstract: When channel allocation is scheduled in a dynamic TDMA frame for communications with a plurality of terminals and then the scheduling results are reflected in a frame table, a shift register is used as the frame table. The shift register comprises a plurality of register units coupled in tandem. Each of the register units is allocable to a channel for one of the plurality of terminals. A shift controller is coupled to the shift register, and controls the shift register such as to write a new channel defining data at a given register unit and collectively shift a plurality of channel defining data respectively stored in a plurality of register units so as to make space for said new channel defining data at said given shift register.

Abstract: A system and method for managing the allocation of Time Division Multiplexing (TDM) timeslots in a network switch. The network switch may use a TDM cycle comprising multiple timeslots to manage shared resources and to schedule data ingress and egress through the ports of the current configuration, wherein each port is assigned one or more timeslots. The network switch may be reprogrammed to support one of multiple timeslot assignment schemes for one of multiple port configurations. The network switch may support configurations with varying numbers of ports, e.g. 8- and 16-port configurations. A network switch may also support configurations where two or more ports are combined to form one port, for example, a 2 Gbs Fibre Channel port. To meet the requirements of the various configurations, the timeslot assignment scheme may be reprogrammed to meet the scheduling requirements of each of the possible port configurations.

Abstract: In a communications network wherein a central station (CS) is coupled to a plurality of network terminals (T1, T2, T3, T4) via the cascade connection of a common link (L) and respective individual links (L1, L2, L3, L4), and wherein the network terminals (T1, T2, T3, T4) transmit information in a time multiplexed way towards the central station (CS), the central station (CS) assigns timeslots for the upstream transmission to the network terminals (T1, T2, T3, T4) by broadcasting group identifiers (GI1, GI2, GI3, GI4). Each group identifier (GI2) identifies a precomposed group (G2) of network terminals (T2, T3) which respect a predetermined order for occupying upstream timeslots. In this way, the central station (CS) can assign a plurality of timeslots to a plurality of network terminals (T2, T3) by transmission of only one single group identifier (GI2).

Abstract: A communication gateway for communicating presence information between a connectionless packet-switched signaling network and an Internet Protocol (IP) network includes a message bearer configured to receive and send messages over a connectionless packet-switched signaling network and a translator, in communication with the message bearer, operable to translate messages received from the connectionless packet-switched signaling network into messages suitable for transport over an IP network and operable to translate messages received from the IP network into messages suitable for transport over the connectionless packet-switched signaling network.

Abstract: A node in an asynchronous transfer mode exchange network comprises a bandwidth monitor circuit for calculating a bandwidth used for a virtual path by measuring a cell amount entered into each virtual path, cell stored buffers for respectively storing an input cell for every virtual path, a bandwidth allocation control circuit for deciding a bandwidth allocation ratio, in accordance with a used bandwidth ratio obtained by reference to each bandwidth used for every virtual path from the bandwidth monitor circuit, depending on a change of the Queue length in a cell within the cell stored buffer, and an output bandwidth control circuit for controlling output of the respective cell stored buffers, in accordance with the bandwidth allocation ratio decided by the bandwidth allocation control circuit.

Abstract: For each competing data stream, a particular share is taken from a resource pool and is allocated. Measured data are used as required to make dynamic alignments by virtue of the resource pool's involved returning resources which are not required to the shared resource pool, or greater shares are allocated to them from the shared resource pool. If the resource requirement reaches a prescribed threshold value close to the allocated particular share, its share is increased, provided that resources which have not yet been allocated are available in the resource pool. If it is not possible to increase the particular share, then only after a prescribed time period has elapsed is another check carried out to determine whether an increase is necessary (measured requirement has reached threshold value) and possible. Conversely, a particular portion of a particular share is returned to the shared resource pool if it has not been required for a prescribed time period.

Abstract: Systems and techniques for establishing a communication link wherein a transmission source delimits frame boundaries of a payload, calculates a value as a function of a subset of the payload, and appends the value to the payload within the frame boundaries before transmission of the frame. A receiving source calculates a value as a function of a subset of the payload, compares the calculated value to the received value, and detects a valid payload as a function of the comparison. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: Systems and methods are provided for transferring physical layer control information from a central access point to individual subscriber units while maintaining transparency to higher layers. Adaptation of wireline MAC protocols to wireless applications is greatly facilitated. Subscriber unit power level may be controlled from the central access point.

Abstract: The present invention includes a subscriber-switching device and method in a system of asymmetrical digital subscriber lines ADSL. The subscriber-switching device includes multiple subscriber units including multiple subscriber ports, respectively; a redundancy subscriber unit including multiple subscriber ports, a network unit for transmitting data inputted from the multiple subscriber units to networks, a rear unit on a back plane of a shelf for transmitting data inputted from at least more than one of the subscriber lines to the subscriber unit, a common line board for connecting the subscriber lines of the rear unit to the redundancy subscriber unit through the common line, a switching means for switching among the subscriber port of the subscriber unit, the redundancy subscriber unit, and the common line board, and a controller for controlling mutual operation flows among the above units and means.

Abstract: An apparatus (30) for and method of synchronizing OFDM signals utilizes a single baud to provide synchronization in time, frequency, and per-subcarrier rotation (201). Timing and fractional subcarrier frequency synchronization may be obtained from either a known or unknown (e.g., data symbol) baud having known symmetry properties. Because all three synchronization tasks may be accomplished utilizing a single sync baud, the present invention spectrally efficient. A differential correlation metric is utilized to efficiently provide integer subcarrier frequency synchronization and per-subcarrier rotation synchronization.

Abstract: A distributed method and apparatus for assigning a unique identifier number to devices connected in a sequential fashion and determining a total device count is presented. Additionally, a method and apparatus for enabling the support of a variable number and type of time slots within a time division multiplexed serial protocol is presented.

Abstract: An optical transport network comprises a number of nodes, or routers, which are coupled together via optical fibers. When a physical link comes up between a node and a neighboring node, a handshake between the node and the neighboring node recognizes the link such that the node, and the neighboring node, include it in respective link assignment tables. In addition, the node and the neighboring node negotiate a predefined sequence for assigning link resources from their respective assignment tables for satisfying future connection requests.

Abstract: A method and apparatus are provided for flexible time-division multiplexing, and demultiplexing, of serial line data, from 1-n client lines, based on the SONET standard (e.g. OC-48 or OC-192) whereby a predetermined and reconfigurable number of STS-1s are allocated to each client. A multiplexer includes 1 to n mappers for mapping the data of 1 to n clients, according to a predetermined bandwidth allocation, to an N×STS-1 SON ET payload, each mapper using y STS-1s where y is 0 to N, the y STS-1s being selected on a sequential or non-sequential concatenation basis from the N STS-1s. Each mapper maps the data of one client and each allocated STS-1 is allocated to one client and the total number of STS-1s allocated to the clients is less than or equal to N. An aggregator aggregates the mapped data into a composite STS payload comprising N STS-1s. A bandwidth allocation receiver receives the bandwidth allocation.

Abstract: A method and apparatus for interfacing a parallel connection, the parallel connection transmitting high bit-rate signals for a short distance. The method comprises: receiving a synchronous N-bits input data flow at a first input frequency; inserting said input data flow into parallel packets having a given length; and outputting said packets having a given length at a second output frequency onto a M-wires parallel connection.

Abstract: A system and method for implementing a next generation laser-like light source with Free Electron Lasers (FELs) are provided whereby the construction of a Free Electron Laser (FEL) is customized through the use of individual modules having specified characteristics. Such individual modules include conventional lasers, electron guns, linear accelerators, magnetic bunch compressors and permanent magnet, hybrid, and electromagnetic, undulators or a combination of these undulators. These individual modules are arranged to exploit the occurring fundamental and nonlinear harmonics generated in each SP HG FEL to be used themselves as a light source, or alternatively to be a coherent seed for another module, such as, in high-gain harmonic generation (HGHG). An efficient method for producing shorter wavelengths of a synchrotron light source is provided. A three step process including imprinting, upconverting or wavelength shifting and reinforcing or strengthening of the electron beam microbunching is provided.

Abstract: Device for locking the wavelength of an optical signal emitted by a source, comprising: a coupler (2) capable of extracting a fraction of the said optical signal, a splitter (4) capable of dividing the said fraction of the said optical signal into a first sub-fraction and a second sub-fraction, a first filter (FP1) capable of filtering the said first sub-fraction and of generating an optical signal when its wavelength is displaced to values below the wavelength of the optical signal to be locked, a second filter (FP2) capable of filtering the said second sub-fraction and of generating an optical signal when its wavelength is displaced to values above the wavelength of the optical signal to be locked, an opto-electronic device (6) capable of converting the said first filtered sub-fraction of the optical signal and the said second filtered sub-fraction of the optical signal, and of generating a signal corresponding to the said size of the displacement and a signal identifying the direction of the said displacem

Abstract: An apparatus and method for controlling the phase of a tunable laser is provided. Stabilization of the mode of a laser beam is provided as the laser is tuned to a target frequency. For one embodiment, a laser generates a reference beam and an output beam. The power of each of beam is measured by optical detectors, and a ratio thereof is utilized to detect when a mode hop occurs as the laser is coarsely tuned. The average of the pre and post mode hop ratios is utilized as a control setpoint while finely tuning the laser to the target frequency. Wavelength lockers, optical power dividers and optical detectors are utilized to determine power levels of the reference and output beams while also monitoring frequency characteristics thereof. A control unit utilizes the outputs from the wavelength locker to control the operation of the extended cavity laser during and after tuning.

Abstract: An apparatus with an optical functional device includes a first substrate, a first optical functional device with a functional portion provided on the first substrate, a first wiring electrode for injecting a current into or applying a voltage to the functional portion of the first optical functional device, a second substrate, and a second wiring electrode. The first wiring electrode is formed on the first substrate and includes a first portion electrically connected to the functional portion, a first extension portion extending from the first portion to an outside of the functional portion and a first pad portion connected to the extension portion outside the functional portion, and the second wiring electrode is formed on the second substrate and includes a second pad portion and a second extension portion extending from the second pad portion.

Abstract: A laser-based light source includes a laser (26), two optical detectors (27), a diffraction grating (29) mounted in a can (28), and a controlling circuit (31). A plurality of parallel grooves (293) is defined in a bottom face (292) of the diffraction grating. Each groove has a depth “d.” A groove separation “a” is defined between any two adjacent grooves. A groove cycle “b” is defined as a sum of the distance a and a width of any one groove. A light intensity of light beams depends on the values of “d”, “a” and “b”. By selecting a desired duty cycle f=a/b for the diffraction grating, the reflected light beams are converged into ±1 order light beams. Almost all the ±1 order light beams are collected by the optical detectors, notwithstanding variations in operational temperature. The controlling circuit receives feedback signals from the optical detectors.

Abstract: A control circuit includes a power controller for adjusting a bias current to a laser diode to change the power output of the laser diode, the change in power having a corresponding wavelength shift effect on the nominal operating wavelength of the laser diode and a monitoring circuit for sensing the bias current to the laser diode and for generating an output signal in response to the sensed bias current. The control circuit further includes a wavelength controller which receives the output signal from the monitoring circuit and in response to the output signal compensates for the wavelength shift such that the laser diode maintains operation at the nominal wavelength.

Abstract: A semiconductor laser diode has a GaAs substrate and a resonant cavity formed on the GaAs substrate. The resonant cavity includes a QW structure having a GaInAsN well layer and a AlGaAs or GaInAsP barrier layers. Specific combination of the indium content and the nitrogen content in the well layer alone or in combination with the specific composition of the barrier layers provides a long-term operation at a higher output power.

Abstract: A semiconductor laser has a first conduction-type cladding layer, an active layer, and a second conduction-type cladding layer formed on a first conduction-type semiconductor substrate. The second conduction-type cladding layer has a mesa-type stripe-shaped recessed portion in at least four spots, so as to form a central ridge portion, which constitutes a ridge-type current confinement portion, and two or more lateral ridge portions, which are positioned on both sides of the central ridge portion, have a height larger than to that of the central ridge portion, and include the second conduction-type cladding layer. An insulation film with a lower refractive index than the second conduction-type cladding layer is formed in a pair of stripes disposed respectively in the regions from the side surface of the second conduction-type cladding layer on both side surfaces of the central ridge portion toward the outside. The insulation film is not formed on the central ridge portion.

Abstract: There is provided a surface emitting laser device of fundamental lateral mode oscillation that suppresses a resistor increase and that is favorable in reliability. A GaAs layer 16 having such a thickness as to exhibit a high reflection factor with respect to oscillation wavelength is formed on an upper DBR mirror. In addition, a groove having such a depth that the GaAs layer located directly under it has such a thickness as to exhibit a low reflection factor with respect to oscillation wavelength is formed on the GaAs layer in such a position as to stride an extension line of a boundary between an Al oxide layer and an AlAs layer. As a result, laser oscillation can be conducted only in a post region surrounded by the groove.

Abstract: In a process for producing a semiconductor laser element, a mask having a pair of openings is formed on a current stopping layer formed above a first cladding layer; a pair of first grooves are formed in the current stopping layer by etching using the mask; portions of the first cladding layer located at the bottoms of the pair of first grooves are etched off so as to form a pair of second grooves in the first cladding layer, and a portion of the current stopping layer left between the pair of first grooves are etched off; the pair of second grooves are filled with a material having a refractive index higher than that of the first cladding layer; and a second cladding layer is formed over the pair of second grooves and the region of the first cladding layer located between the pair of second grooves.

Abstract: A lighting device suitable for low power applications, such as backlighting a liquid crystal display (LCD), includes plural light emitting components and photovoltaic elements formed on a monocrystalline silicon substrate. To fabricate the lighting device, high quality epitaxial layers of monocrystalline materials can be grown overlying the silicon substrate by forming a compliant substrate for growing the monocrystalline layers. One way to achieve the formation of a compliant substrate includes first growing an accommodating buffer layer on a silicon wafer. The accommodating buffer layer is a layer of monocrystalline oxide spaced apart from the silicon wafer by an amorphous interface layer of silicon oxide. The amorphous interface layer dissipates strain and permits the growth of a high quality monocrystalline oxide accommodating buffer layer. The accommodating buffer layer is lattice matched to both the underlying silicon wafer and the overlying monocrystalline material layer.

Abstract: High quality epitaxial layers of monocrystalline materials can be grown overlying monocrystalline substrates such as large silicon wafers by forming a compliant substrate for growing the monocrystalline layers. An accommodating buffer layer comprises a layer of monocrystalline oxide spaced apart from a silicon wafer by an amorphous interface layer of silicon oxide. The amorphous interface layer dissipates strain and permits the growth of a high quality monocrystalline oxide accommodating buffer layer. The accommodating buffer layer is lattice matched to both the underlying silicon wafer and the overlying monocrystalline material layer. Any lattice mismatch between the accommodating buffer layer and the underlying silicon substrate is taken care of by the amorphous interface layer. In addition, formation of a compliant substrate may include utilizing surfactant enhanced epitaxy, epitaxial growth of single crystal silicon onto single crystal oxide, and epitaxial growth of Zintl phase materials.

Abstract: The invention features an edge-emitting semiconductor signal laser having an active region to produce laser light. There is provided a semiconductor pump laser monolithically integrated with the edge-emitting signal laser. The pump laser includes a photon emissive active region to provide photopumping of the active region of the edge-emitting signal laser, thereby providing optical excitation of the active region of the signal laser.

Abstract: A light source is disclosed. In one aspect, a gain region defined by a first and second mirror is provided having a corresponding resonant mode, and an external cavity defined by a third mirror and the second mirror is also provided having a plurality of resonant modes. A birefringent crystal is then disposed within said external cavity for the purpose of controlling the state of polarization.

Abstract: A device for generating blue or green laser light by the use of a device comprising an infrared high power semiconductor laser or an infrared high power semiconductor laser bar or array, a diffractive optical device, and an optical device utilizing a non-linear crystal to generate the blue or green laser light. In one embodiment, the diffractive optical device comprises a volume holographic transmission grating and the optical device comprises a ring resonator. In another embodiment, the diffractive optical device comprises a reflective diffraction grating feedback mechanism and the optical device comprises a ring resonator. In another embodiment, the optical device comprises a parabolic or non-planar feedback mechanism and a ring resonator. In another embodiment, the diffractive optical feedback device, which can be in the form of digital/binary optics, is attached to the semiconductor laser source.

Abstract: The invention relates to a laser amplifier system consisting of a solid body, which comprises a laser-active medium, of an excitation source for producing an excited state of the laser-active medium, and of an amplifier radiation field, which repeatedly permeates the solid body and out of which a laser beam can be decoupled. The aim of the invention is to improve a laser-amplifier system of this type so that the highest number of passages of the amplifier radiation field through the solid body can be attained using optical means that are provided in the most simple possible form. To this end, the invention provides radiation field guiding optics which enable the amplifier radiation field to enter the solid body in the form of a number of incident branches with locally different trajectories, and which enable the amplifier radiation field to exit the solid body in the form of at least one emerging branch with a trajectory that differs locally from those of the incident branches.

Abstract: A semiconductor ring-type optical device having an optical cavity with at least one partially transmitting facet which serves as an emergence region for light propagating within the optical cavity has the upper surface of the cavity coated with a conductive layer which is divided into at least two segments so as to provide two separate electrodes to allow application of separate voltages to the two segments. When different voltages are applied, one segment of the laser will carry a lower current density than the other, resulting in a lower gain under the electrode having the lower voltage and causing the generated laser wavelength to experience a shift to shorter wavelengths. Accordingly, variations in the voltage applied to the two electrodes allows tuning of the laser output wavelength.

Abstract: A ring-type laser including a traveling wave cavity which incorporates at least first and second straight cavity sections and at least one curved cavity section. Corresponding first ends of the straight cavity sections are interconnected at a first light-emitting facet, and second ends of the straight sections are interconnected by the curved waveguide. Additional curved and straight sections can be linked to provide various ring configurations.

Abstract: A device (10) for calibrating tympanic thermometers includes an enclosure (12) which may be heated or cooled depending upon the testing temperature. Within the enclosure (12) there is provided a sealed flask (14) which contains substance (16) which melts at the test temperature (this may be ethylene carbonate, melting point 36.3° C.). Located within the sealed flask (14) is a re-entrant well (18) which provides the blackbody for testing tympanic thermometers and a viewing aperture (20). The well (18) is treated to achieve a high surface emissivity. The device (10) allows the testing of thermometers by measuring the triple point or melting point of the substance (16). As the temperature of the substance (16) is accurately known, so is the temperature in the blackbody cavity (18) and thermometers can be calibrated thereby.

Abstract: To provide a differential scanning calorimeter in which rise and fall of temperatures of a sample and a reference substance follow rise and fall of temperature of a heat sink with excellent response maintaining a structure of a differential scanning calorimeter having a structure of providing stability of a base line constituting a characteristic of a heat flux type while achieving response equivalent to or faster than that of a power compensation type, in a structure of a heat flux type differential scanning calorimeter in which a heat flow path between a sample holder and a heat sink is formed by a metallic material having excellent heat conductance, heaters for power compensation are attached to the sample holder and a reference holder.

Abstract: An apparatus for measuring the temperature of an object. The apparatus includes a device for establishing a standing wave pattern or radiation emanating from the object and a coupling device for coupling the radiation to a detector, such as a measuring radiometer.

Abstract: An improved apparatus for measuring the temperature of an object such as a food object. Also, a related method, container, transportation member and production line which utilizes this apparatus. The apparatus includes a coupling device for coupling radiation emanating from the object to at least a first radiation temperature measuring radiometer, and a first device for switching measurement circuitry between measuring the radiation temperature of at least a first reference temperature and the radiation temperature of the object.

Abstract: The present invention relates to a cooking thermometer which can measure a temperature in contact with foodstuffs directly or around foodstuffs during the cooking process. Particularly, the present invention relates to a cooking thermometer which inhibits the proliferation of bacteria on the surface of the thermometer and is coated with an antibacterial compound such as titanium dioxide.

Abstract: One embodiment of the invention is a subscriber unit for transmitting communication signals. The subscriber unit comprises a cipher stream generator which generates a cipher stream to encipher a digital data stream. A data stream mixer mixes the cipher stream with the digital data stream. An antenna radiates the mixed cipher and data stream as a communication signal. Another embodiment of the invention is a subscriber unit for receiving communication signals. The subscriber unit comprises a cipher stream generator for generating a cipher stream with the received communication signal to produce a decoded data stream. The cipher steam_generator includes first and second linear feedback shift registers. Each has a clock input and an output. The outputs are combined to generate the cipher stream. The output of the second register is combined with a clock signal which is inputted to the clock input to the first register.

Abstract: A novel power-controlled random-access method allows a mobile station to gain fast access to the base station. At the mobile station, a composite power control command is devised after an initial access attempt. The determination of the composite command uses an open-loop power-control symbol and a closed-loop power-control symbol, to decide the action of the mobile station upon transmission of its next random-access signal. In the preferred embodiment, the composite power control command can specify different levels of increase or decrease in transmission power, and the composite power control command can specify a back-off by the mobile station. This composite power-control mechanism can help resolve collision between mobile stations accessing the same random access sub-channel and therefore maintain a low-delay in the random-access process and a high-utilization on the access-channel resource.

Abstract: A code division multiple access base station receives K data signals over a shared spectrum. The base station receives and samples a combined signal having the K transmitted data signals. A combined channel response matrix is produced. A block column of a cross correlation matrix is determined using the combined channel response matrix. Each block entry of the block column is a K by K matrix. Each block entry of the block column is a K by K matrix. A fourier transform of a complex conjugate transpose of the combined channel response matrix multiplied to the combined signal samples is taken. An inverse of a fourier transform of each block entry is multiplied to a result of the fourier transform to produce a fourier transform of the data vector. An inverse fourier transform of the data vector fourier transform is taken to produce data of the K signals.

Abstract: A weighted mean arrival time determines a delay offset of a fractionally spaced equalizer. The weighted mean arrival time is determined using path arrival times and energies from a Rake receiver. The difference between a weighted mean arrival time and a current delay offset is set to a difference X, in units of the equalizer tap spacing. If the difference X is greater than or equal to 1 or less than or equal to −1, then the current delay offset is updated by an incremental delay offset and the equalizer filter coefficients are shifted by a number of tap spacings. Otherwise, the current delay offset is not updated and the filter coefficients of the fractionally spaced equalizer are not shifted. Adaptation of the filter coefficients and updates of the delay offset of the equalizer occur only during pilot bursts so as to minimize adaptation transients.

Abstract: A plurality of receiving units (26) forming a multiuser receiver are each provided with a selector (2) which selects for use either a propagation path estimated value determined by a propagation path estimator (18) contained in the same receiving unit or a propagation path estimated value determined by a propagation path estimator contained in another receiving unit. When the despreading code used in a first despreader (10) is a pilot signal despreading code, the selector (20) selects the propagation path estimated value determined by the propagation path estimator (18) based on the despread pilot signal output from the first despreader (10), and supplies the selected propagation path estimated value to a coherent detector (24), while when a user channel despreading code is used in the first despreader (10), the selector (20) selects the propagation path estimated value determined in another receiving unit and supplies it to the coherent detector (22, 24).