Abstract: A system and method are described herein that are capable of reducing overhead while keeping the traffic separation characteristics between two routers by establishing and using a generic routing encapsulation (GRE) tunnel directly over a link running a point-to-point protocol (PPP) that connects the two routers. Because, the system and method run GRE sessions directly over the PPP link means there is no need to configure the GRE tunnel over an Internet Protocol (IP) connection which means that outer IP header information does not need to be sent across the link. The elimination of the outer IP header reduces the overhead in the traffic sent between the two routers.

Abstract: A technique for providing multiple Fiber Channel frames in one frame-mapped GFP transport frame. GFP conventions are followed, except that a Distributed Delimiter marks each Fiber Channel frame in the payload of GFP transport frame. The Distributed Delimiter has a Fixed Pattern field which varies distinctly from the special K28.5 character which indicates Fiber Channel Ordered Sets and has a Frame Length field to indicate the length of the Fiber Channel frame.

Abstract: Disclosed herein are methods of providing a client with local area network connectivity and access to other services in a cable network. One such method includes: allocating bandwidth in the network to support bi-directional data communication between the host and a central concentrator. Bandwidth is allocated for a downstream flow on at least one downstream frequency channel based on a mapping between the downstream flow and a particular octet in a downstream packet. Bandwidth is allocated for an upstream flow on at least one non-shared upstream tone. The method also includes conveying a bi-directional data flow between the host and the concentrator over the allocated bandwidth, including conveying the upstream flow using the allocated bandwidth and conveying the downstream flow using the allocated bandwidth. The method also includes utilizing bandwidth in the network not allocated to data communications to provide the host with at least one audio/visual service.

Abstract: A number of features for enhancing the performance of a wireless communication system, in which data is transmitted between a central node and a plurality of subscriber nodes located remotely with respect to the central node, are presented. The power transmission level, slot timing, and equalization of the subscriber nodes are set by a ranging process. Data is transmitted by the subscriber nodes in fragmented form. Various measures are taken to make transmission from the subscriber nodes robust. The uplink data transmission is controlled to permit multiple access from the subscriber nodes.

Abstract: A process control routine may include a first internal function block for executing a control operation based on an input signal and an information conduit communicatively connected to the first internal function block. The information conduit may have an output adapted to provide the input signal to the first internal function block. The process control routine may further include an external function block communicatively connected to the information conduit and adapted to generate the input signal such that the output signal is directly provided to the information conduit prior to the execution of the control operation.

Abstract: There is disclosed a method of transmitting data packets from a transmitter to a receiver each having a stack of communication protocol layers which comprises a data Link Layer (LL), by using a Segmentation And Re-assembly (SAR) mechanism implemented within a SAR layer intermediate between the LL and an upper layer, as well as an error recovery mechanism implemented within the LL. The SAR mechanism performs, in a transmission direction, the function of segmenting Parent Packets (PPs) handled by the upper layer into consecutive segments of shorter length and the function of providing some segmentation information. The segmentation information comprises, for each segment, a two-level sequence numbering comprising a PP Sequence Number (PPSN) which identifies the PP which said segment belongs to, and a Segment Sequence Number (SSN) which identifies the rank of the segment within the PP.

Abstract: A system and control unit (26) for transmitting and distributing multiplexed audio data over an optical network (32). The control unit (26) comprises an audio sampler (36), a microcomputer (34), and an optical network interface (40). The audio sampler (36) samples a plurality of electrical signals (42A-D) from transducers (22A-D) and generates a plurality of raw audio data streams (54A-D) from the electrical signals (42A-D). The audio sampler (36) is capable of sampling the electrical signals (42A-D) at a fraction of a frame synchronization rate (Fs) of the optical network (32). The microcomputer (34) has an audio processor function (56) and a multiplexer function (58). The audio processor function (56) is capable of processing the raw audio data streams (54A-D) to generate a single processed audio data stream (62) at the frame synchronization rate (Fs) of the optical network (32). The multiplexer function (58) is capable of generating a multiplexed audio data stream (66) having a plurality of frames (70).

Abstract: A first data packet is sent through a system under measurement (SUM) from a sender side to a receiver side. A time distance d between the first data packet and a second data packet consecutive thereto in a packet flow is observed on the sender side. A value of d is written into a payload of the second data packet. The second data packet is sent through the SUM. The first data packet and the second data packet are received on the receiver side. A time difference D between the first data packet and the second data packet is observed on the receiver side. The value of d is extracted, at the receiver side, from the payload of the second data packet. The jitter is determined based on the value of d extracted from the payload of the second data packet and the value of the time difference D.

Abstract: Disclosed is a frequency multiply circuit for outputting an output signal obtained by variably multiplying the frequency of an input signal includes a synchronous delay circuit, a multiplexing circuit, and a control circuit. The synchronous delay circuit includes a period measuring delay circuit for measuring the period of the input signal and delay reproducing delay circuits each with a delay time thereof variably set based on the period measured by the period measuring delay circuit, for respectively reproducing the delay time. The multiplexing circuit receives a plurality of signals of different phases output from the synchronous delay circuits, for multiplexing. The control circuit variably sets the number of the delay stages of the period measuring delay circuit and the numbers of the stages of the delay reproducing delay circuits, according to the set frequency-multiplication factor.

Abstract: Normally ordered robust VSB data are reordered in accordance with a first interleave to produce reordered robust VSB data. The reordered robust VSB data and ATSC data are reordered in accordance with a second interleave to produce normally ordered robust VSB data and reordered ATSC data. The normally ordered robust VSB data and reordered ATSC data are time multiplexed for transmission to a receiver. The receiver discards the reordered ATSC data or the normally ordered robust VSB data depending upon receiver type or user selection. A robust VSB receiver is able to process the normally ordered robust VSB data upstream of an outer decoder without an interleave thereby avoiding the delay associated with an interleave.

Abstract: A channel adapter, configured for sending frame data according to link widths selected based on management frames received from a link partner, includes a multiplexer circuit configured for selectively switching the frame data supplied according a prescribed maximum link width, to one of a plurality of available link widths for a transmit bus, and a bus controller. The bus controller is configured for controlling the multiplexer circuit to switch the frame data to one of the available link widths, including the prescribed link width, based the selected link width. Hence, a channel adapter can be configured for an optimum link width for communication with a corresponding channel adapter on a peer node.

Abstract: This invention provides a circuit and a method for very high-speed multiplexers. It provides a circuit that can produce an arbitrary number of multiple signal multiplexers. It also provides a circuit and a method which converts a parallel data bus into a serial data path. This invention contains an overlapped data generator, which takes in a data bus and outputs even and odd signals to a selective mux. It also contains a selective mux, which receives even and odd internal data bits from said overlapped data generator and which outputs one serial data bit. It also contains a phase locked loop/delay locked loop, PLL/DLL, which receives a set of phase clocks and which outputs five evenly-phase-distributed clock signals to a data select signal generator. Finally, the circuit includes a data select signal generator, which receives said five evenly-phase-distributed clock signals and which generates a ten-bit data select signal bus.

Abstract: The present invention is a self-seeded laser diode. The laser diode obtains a gain by itself without using expansive erbium-doped fiber amplifiers. Hence, the cost is reduced and the system is simplified.

Abstract: An optical apparatus including a tunable master laser from which all or some of a beam is injected into at least one “slave ” laser having a cavity with an amplifier medium and a dynamic holographic medium that forms a self-adapted spectral filter to maintain oscillation of the slave laser at a wavelength imposed by the master laser during injection after injection has stopped.

Abstract: A method, system, and electrical circuit for determining a magnitude of a modulation current provided to a laser device based upon an approximated slope efficiency, wherein the approximated slope efficiency is based upon at least one discrete incremental change in a bias current to the laser device and at least one change in output power from the laser device.

Abstract: A power supply unit includes a transformer, and outputs a first power supply voltage which is used for logic processing and a second power supply voltage which is used for driving a drive unit. A voltage control unit includes a shunt regulator to a detection voltage input terminal of which is connected a voltage which has been voltage divided from the first power supply voltage, and controls the second power supply voltage to a predetermined voltage value. And a voltage application control unit applies a voltage which is determined in advance to the detection voltage input terminal of the shunt regulator, when the replay unit is in a stopped mode where replay by the replay unit of data recorded upon the optical disk is stopped.

Abstract: A vertical-cavity, surface-emission-type laser diode includes an optical cavity formed of an active region sandwiched by upper and lower reflectors, wherein the lower reflector is formed of a distributed Bragg reflector and a non-optical recombination elimination layer is provided between an active layer in the active region and the lower reflector.

Abstract: An apparatus and source arrangement for filtering an electromagnetic radiation can be provided which may include at least one spectral separating arrangement configured to physically separate one or more components of the electromagnetic radiation based on a frequency of the electromagnetic radiation. The apparatus and source arrangement may also have at least one continuously rotating optical arrangement which is configured to receive at least one signal that is associated with the one or more components. Further, the apparatus and source arrangement can include at least one beam selecting arrangement configured to receive the signal.

Abstract: The invention relates to a spread-signal multiplexing circuit for frequency-multiplexing a plurality of spread signals that were generated in parallel according to the SSMA scheme. An object of the invention is to adapt to various degrees of multiplicity and to keep the SN ratio and the power efficiency high. To this end, a spread-signal multiplexing circuit of the invention comprises an amplitude monitoring part for multiplexing a plurality of spread signals and determining amplitude of a resulting signal in time-series order; a delaying part for delaying the spread signals in parallel by a time that is equal to a propagation delay time of the amplitude monitoring part; and a multiplexing part for generating a multiplexed signal by multiplexing the delayed spread signals while weighting the delayed spread signals in parallel using weights that are smaller as an average value of the determined amplitude is larger.

Abstract: A base station is in a spread spectrum code division multiple access (CDMA) communication system with co-exists with a diverse system of existing users. The diverse system selectively utilizes various frequencies within a selected range of frequencies. The base station generates a plurality of spread spectrum CDMA data signals using pseudo random chip code sequences. The spread data signals encompass the selected range. The base station notch filters the spread data signals at frequencies within the selected range used by the diverse system. The notch filtered spread data signals are transmitted in CDMA cellular radio communications.

Abstract: A device for detecting data synchronization in data communications includes pseudorandom noise (PN) lock circuits (101, 113, 127). The PN lock circuits (101, 113, 127) receive an input data stream (109). Each of the PN lock circuits (101, 113, 127) is time offset with respect to the other PN lock circuits. Each of the PN lock circuits (101, 113, 127) outputs a PN sequence responsive to the input data stream. For each PN lock circuit, there is provided a component (105, 117, 131) for comparing the PN sequence from the respective PN lock circuit to the input data stream, to determine whether the input data stream and the PN sequence are synchronized. An indication (107, 119, 133) that the data is synchronized is provided when the input data stream and the PN sequence are synchronized.

Abstract: A method and device for transmitting data in the form of a series of blocks in which each block of data is subjected to a frequency conversion in order to be transmitted at a carrier frequency. The method includes inserting a sequence of padding data between a first block of data intended to be transmitted at a first carrier frequency and a second block of data intended to be transmitted at a second carrier frequency, and transmitting the padding data while the frequency changes from the first carrier frequency to the second carrier frequency.

Abstract: Communication circuitry uses a combination of Pseudo-Noise (PN) coded and non-PN coded transmission periods to represent different data values. In one embodiment, a number of data values are encoded into a smaller second number of encoded ternary values. The Pseudo-Noise (PN) codes are transmitted representing some of the encoded ternary values and no transmitted PN codes represent other encoded ternary values. The throughput of spread spectrum radio systems is increased by representing data values in fewer spread spectrum time slots.

Abstract: The present invention relates to a spreading signal assigning method and a signal transmitting method in a direct sequence CDMA mobile communication system, a mobile wireless communication system using the methods, and a transmitter, a receiver and a transceiver in the mobile wireless communication system in which an assignment method of a second spreading code is devised such that various services can be provided. The invention is configured such that a signal spread with the second spreading code is transmitted between a base station and a mobile station by assigning a code associated with each base station group or a code associated with each network type to which the base station group belongs as the second spreading code.

Abstract: A CDMA communication system includes a signal processor which encodes voice and nonvoice signals into data at various rates, e.g. data rates of 8 kbps, 16 kbps, 32 kbps, or 64 kbps as I and Q signals. The signal processor selects a specific data rate depending upon the type of signal, or in response to a set data rate. When the signal is received and demodulated, the baseband signal is at the chip level. Both the I and Q components of the signal are despread using the conjugate of the pn sequence used during spreading, returning the signal to the symbol level. Carrier offset correction is performed at the symbol level. A lower overall processing speed is therefore required.

Abstract: A method for applying one or more code values to an input signal value to produce an output signal value in a CDMA communications scheme, wherein the code value or values may lie only either on or equally distant from an orthogonal pair of axes defining a two dimensional signal space, the input and output signal values each have components along each axis and the method comprises processing, via a logic function, the code value or values to produce two multiplier values and a selector value, creating two product values by multiplying the multiplier values with respective components of the input signal value, negating one of the product values to produce a third product value and selecting, on the basis of the selector signal, two of the three product values to become the components of the output signal value.

Abstract: It is an object to propose a way to assign channelization that is applicable to a case in which the number of multiplexing of DPDCHs (Dedicated Physical Data Channels) is at least five for overshoot of HPSK (Hybrid Phase Shift Keying) modulation. Assignment of channelization codes is set as follows. For all possible combinations of channelization assigned to given data channels and control channels, a transition ?1 from the first chip to the second chip and a transition ?2 from the third chip to the fourth chip are obtained. For each transition, 0 degrees or 180 degrees is desirable, and 90 degrees is the worst, so that a combination is obtained in which squares of sine of respective transitions become the smallest. Consequently, by obtaining a combination that makes sin2 ?1+sin2 ?2 the smallest, the one that is close to the most desirable combination can be obtained.

Abstract: A wireless telecommunications system includes a base station, a plurality of remote stations, a first channel for general page messages containing paging information and broadcast databurst message references, and an auxiliary channel for broadcast databurst notification indicators for the purpose of increasing standby time in remote stations configured to receive broadcast databurst messages.

Abstract: In a CDMA receiving apparatus, a delay profile using a desired constraint length is generated by a delay profile generating unit from received signal wave-form data recorded on a received signal wave-form buffer unit. Several demodulation paths are selected at peak position of the delay profile by the path search unit. Demodulation symbols which are generated from received signal wave-form data of each demodulation path by the channel demodulating unit are brought into in-phase by an adjustment angle which is obtained by the channel estimating unit. If the reception quality which is measured by the reception quality measuring unit is lower than a predetermined value for a combined demodulation symbol which is combined by a RAKE unit, the combination of said selected demodulation paths or the constraint length is changed to repeat the demodulation operation of the same received signal wave-form data.

Abstract: The invention relates to a method for transmitting at least one sequence of Np pulses over Np time windows, each pulse being enclosed within a predetermined time chip Tc. The method according to the invention includes a signal characterization step, in the course of which Np detection windows Dj (for j=1 to Np) encompassing predetermined time chips are examined by performing correlations over the detection windows Dj of the received signal with at least a first and a second sinusoidal signal S1 and S2.The method according to the invention enables to limit the processing time and power needed for carrying out the characterization step, which only requires to examine detection windows defined by a signature of a transmitter by using sinusoidal signals, instead of mapping the whole pulse sequence by a correlation with expected pulses.

Abstract: Process for configuring an xDSL-type symmetric modem, comprising the following: detecting a predetermined criterion corresponding to an asymmetric operating mode, in particular an ADSL-type; and in response to said detection, disabling a number of carriers in order to establish an asymmetric operating mode. More specifically, the modem is VDSL-type, operating with up to 4096 carriers and being reconfigurable in ADSL mode with a number of carriers reduced to 256. In one case, said criterion is the detection of signals as defined in recommendation G.994.1 of the International Telecommunications Union of (ITU). Alternatively, mode switching could be controlled based on measurement of the size of the line.

Abstract: A system and method is described for determining a condition of a communication line, such as the absence of a filter device on a digital subscriber line (DSL). A first signal characterized by a high upstream power is activated over the line, and a first set of parameters associated with the communication line is obtained. A second signal characterized by a low upstream power is activated, and a second set of parameters associated with the communication line is obtained. Comparison of first and second sets of parameters is indicative of a condition of the connection and presences or absence of a DSL filter on the communication line.

Abstract: In a configuration testing integrated circuits, the system clock signals are forced to the same frequency as the test clock signals. When the test clock signals and the system clock signals have the same frequency, both clock signals can applied to the integrated circuit through a single terminal, whereby providing a terminal for the exchange of other signals with the integrated circuit. Using the same signals for test and system clocks allows selected components to be eliminated.

Abstract: A testing device for testing transceivers includes a transmitter operable in a first state to transmit signals, a receiver operable in a second state to receive signals and a power coupler coupling the transmitter to the receiver. The testing device further includes an overload protection device operably coupled between the power coupler and the receiver to reduce or maintain the signal strength of a received signal at the receiver based on a control signal. A controller determines a current state of the received signal and generates the control signal based on the current state of the received signal.

Abstract: Noise detection is performed by using the output of the phase comparator that the PLL comprises. The phase comparator outputs a signal that is based on the phase difference between the output of the voltage controlled oscillator and the reference signal. The phase difference reflects the effect of noise on the PLL and, in addition to the characteristics of the noise itself, such as the wave height value of the noise and the frequency component thereof, reflects the tolerance of the PLL to noise, whereby the level of risk that the system can actually be caused to malfunction can be judged.

Abstract: A method of describing texture of a group of frames (GoF) or a group of pictures (GoP) using homogeneous texture descriptors, and a method and apparatus for retrieving a GoF/GoP using the texture description method are provided. The texture description method includes: generating homogeneous texture descriptors of all frames constituting the GoF or all pictures constituting the GoF; and expressing the GoF or GoP using a predetermined representative homogeneous texture descriptor corresponding to one frame or picture to reduce the amount of data.

Abstract: A video compression system includes first and second dual-port memory devices, a third memory device, and first and second processors that may provide enhanced processing, including motion estimation. The first processor may be configured to store in the second memory device first and second video frames and to transfer sequential sets of data from the first video frame corresponding to fields of search. A second set of a plurality of adjacent macroblocks of the second video frame may be compared to macroblocks selected from the field of search. Dual-port memory devices may allow for the concurrent use of shared memory by the two processors as well as data transfer during processing.

Abstract: Presented herein are Tertiary Content Addressable Memory based motion estimator(s). In one embodiment, there is presented a method for encoding a picture. The method comprises storing a reference picture in a memory; taking samples from at least one line of a prediction block; generating at least one data word, the data word being a function of the samples; addressing the memory with the at least one data word; receiving one or more addresses, said one or more addresses associated with one or more blocks; and selecting a reference block from the one or more blocks for the prediction block.

Abstract: A method and apparatus for simplifying an operation for the processing of a warping prediction of dividing an image into patches and deforming each patch by affine transform or bilinear transform. Motion vectors of a plurality of representative points in which a spatial interval has a special feature are obtained from at least one patch formed with a plurality of grid points. Information of the motion vectors are used for synthesis of a predicted image. The division for synthesizing a predicted image in the case of warping prediction is replaced with a shift operation, thereby simplifying the processing by a computer or exclusive hardware.

Abstract: A hybrid high-definition decoder and method are disclosed, for processing signal data as a plurality of block transform coefficients for each of base layer data and enhancement layer data, where the decoder includes a standard-definition decoder for decoding the standard-definition data from a base layer bitstream embodying a standard-definition data sequence, a high-definition decoder coupled to the standard-definition decoder for decoding the difference between the high-definition data and the standard-definition data from an enhancement layer bitstream stored as picture user data embodying a high-definition data sequence, and a two-layer composition unit for composing a high-definition signal data sequence from the standard-definition data and the difference between the high-definition data and the standard-definition data.

Abstract: The present invention relates to method and apparatus of converting a series of data words into modulated signals. This method divides a data word, which a sync signal is to be added in front or rear of when it is written in a recording medium, into two or more word segments, generates for each word segment a number of intermediate sequences by combining mutually different digital words with that word segment, scrambles these intermediate sequences to form alternative sequences, translates each alternative sequence into a (d,k) constrained sequence, checks how many undesired sub-sequences are contained in each (d,k) constrained sequence, and selects one (d,k) constrained sequence for recording on an optical or magneto-optical recording medium among the (d,k) constrained sequences not having the undesired sub-sequence. Applying this method to a modulating device, DSV control can be conducted by much simpler hardware.

Abstract: EMI emissions generated by clock signals in a multi-slot electronic system are reduced by providing out-of-phase clock signals to alternate slots, which cause EMI emissions at typical testing distances and farther to be reduced. An electronic equipment comprises a plurality of slots, each slot operable to receive a clock signal and a plurality of phases of the clock signal, wherein a first phase of the clock signal is routed to a portion of the slots and a second phase of the clock signal is routed to a different portion of the slots. The second phase of the clock signal may be substantially 180° out-of-phase with the first phase of the clock signal.

Abstract: An OFDM demodulation circuit capable of initiating a demodulation process within a short period of time after the reception of a signal and terminating the demodulation early if it has been initiated erroneously, and an OFDM reception apparatus employing the OFDM demodulation circuit. If a threshold value Sth2 in peak detector 122 is not exceeded within a predetermined time T following the output of a symbol timing signal from peak detector 121, namely if a continuation timing signal is not supplied from peak detector 122 to a demodulation process terminating circuit 162 before demodulation process terminating circuit 162 counts predetermined time T (step S115), demodulation process terminating circuit 162, determining that the position at which the demodulation process has been started was wrong, terminates the currently executed demodulation process soon after the completion of the counting of predetermined time T and returns to a received-signal awaiting state (step S111).

Abstract: Precision of channel estimation is improved.

Abstract: A method of shaping an orthogonal frequency division multiplexing (OFDM) signal spectrum of a transmitted signal is disclosed. An input signal including an input component is received and a first instance of the input component is generated. The method also includes determining that a second instance of the input component is to be different than the first instance. The second instance of the input component that is different from the first instance is generated. An output signal to be transmitted is generated and includes the first instance and the second instance of the input component.

Abstract: A method of mitigating transmission delay fluctuations in a communication system having a variable data rate and block-oriented subsystems, such as interleavers. The method comprises interspersing dummy data with genuine data to form a combined data stream for the subsystems. When the data rate decreases, the rate at which dummy data is supplied increases to stabilize the delay. In one embodiment, the dummy data is discarded prior to transmission and may be reintroduced as needed on the receiving end. In another embodiment, the dummy data is transmitted and only discarded after processing at the receiving end. For this later embodiment in a multi-tone system, the dummy data can be sorted onto separate sub-carriers for transmission and the power levels for those carriers can be dropped to reduce overall power consumption and crosstalk. The concept can be used to extend seamless rate adaptation to systems with forward error correction.

Abstract: In a multicarrier receiver, spatial correlation estimates are enhanced by multiplying by weighting values generated from a channel length estimate. The channel length estimate is calculated from a channel estimate (e.g., an estimate of the channel response function) and a signal-to-noise ratio estimate. The spatial correlation estimates represent the correlation between frequency-domain samples from different antennas.

Abstract: A method of receiving data over N receiving antennas from M transmitting antennas, where M and N are integers, includes the steps of receiving N signals over the N receiving antennas, applying the N signals to a space/time decoder, determining noise powers for N channels, with the N channels being based on the N signals, applying Viterbi filtering to the N channels utilizing the noise powers and deriving received data from the filtered N channels.

Abstract: A wireless transmission device which communicates with a wireless reception device is provided with a transmission-signal-generating unit configured to generate, transmission signals having transmission rates arranged in order corresponding to an input order of data items of the information sequence. The transmission device is also provided with a preamble adder which adds, to the transmission signals, respective preamble signals assigned in order of the transmission rates and used for estimation of channel responses at the wireless reception device. The transmission device is further provided with transmission units configured to transmit the transmission signals with the preamble signals added thereto.

Abstract: In a wireless transmitting device which performs transmission by an OFDM using a plurality of subcarriers orthogonal to each other, a plurality of preambles to which a plurality of different subcarrier groups selected from a plurality of subcarriers within an OFDM signal band are allocated are transmitted by using a plurality of transmit antennas, and data is transmitted by using the antennas after the preambles are transmitted.