Abstract: An OFDM frequency control device converts an incoming signal from analog to digital and calculates a correlation value between the guard interval and data part from which the guard interval is copied, of the A/D converted incoming signal. Then, the device averages such correlation values for the first frame through a plurality of frames and detects the peak of the averaged correlation value. Then, by detecting the phase of the peak position, the device generates the control signal for an oscillator. The control signal is set in such a way that a control amount for each time should be a control step ? and is applied to the oscillator. Furthermore, ? is appropriately controlled based on detected information.

Abstract: A method for the selection of forward error correction (FEC)/constellation pairings (800) for digital transmitted segments based on learning radio link adaptation (RLA) including formatting a packet transmission having a predetermined number of information bits (801). The packet is then split into a plurality of segments (803) where an RLA is used (805) to determine the optimum format of the packet. The plurality of segments is then sent to a channel encoder for FEC encoding and symbol mapping (807) at a rate selected by the RLA. The segments are then formatted into packet blocks (809) and transmitted in blocks that form a time slot at a constant symbol rate.

Abstract: A method for transmission, by dividing a transmission resource in a time domain subframe into a plurality of equal duration resource elements in a time and frequency domain, segregating the plurality of resource elements into a plurality of resource regions, modulating information to be transmitted to generate a sequence of modulation symbols at a transmitter, mapping the sequence of modulation symbols into the plurality of resource elements in the plurality of resource regions, and transmitting the modulation symbols via a plurality of antennas using the respective corresponding resource elements to a receiver. The mapping of the modulation symbols in at least one resource region is independent of a certain control channel information that is carried in said time domain subframe, and the mapping of the modulation symbols in at least another resource region is dependent upon said certain control channel information that is carried in said subframe.

Abstract: A method and apparatus for fast cell search based on a chirp reference signal transmission is disclosed herein. A primary synchronization channel (P-SCH) and two secondary synchronization channels (S-SCH1 and S-SCH2) will be utilized. S-SCH1 will comprise a reference sequence having a first index value and S-SCH2 will comprise a reference sequence having a second index value. S-SCH1 and S-SCH2 will be scrambled with a first and a second scrambling code, respectively. The second scrambling code will be based on the first index value.

Abstract: Whether to indicate reception of an access code in a receiver operating in a communications system is determined by receiving a signal and generating a correlation value by correlating the received signal with a reference code. A threshold level is set to a first value if the receiver is in a scan mode. The threshold level is set to a second value if the receiver is in a traffic mode, wherein the second value corresponds to a lower degree of correlation than the first value. The correlation value is compared with the threshold level. Reception of the access code is indicated only if the correlation value compares favorably with the threshold level.

Abstract: In a wireless local area network (WLAN) that includes high-throughput communication devices with multiple antennas and legacy communication devices with single antennas, training tones are transmitted over a plurality of spatial channels during a first portion of an orthogonal frequency division multiplexed (OFDM) packet-training preamble. The training tones are interspersed among subcarrier frequencies of the spatial channels. The training tones are retransmitted during a second portion of the packet-training preamble. The training tones are shifted among the subcarrier frequencies of the spatial channels during the retransmission allowing a high-throughput receiving station to perform a channel estimation on different subcarrier frequencies of the spatial channels. The legacy communication devices may receive and process the training tones and may set their network allocation vector to refrain from communicating during a subsequent interval.

Abstract: There is provided a digital communication device for performing data communication by selecting an appropriate modulation encoding method. Quality measurement means measures the line quality of data communication from a reception signal. Adaptive modulation control means compares the line quality measured by the quality measurement means to a threshold value obtained from the interrelationship between the line quality in a plurality of modulation encoding methods and the through-put characteristic, thereby selecting one of the modulation encoding methods. Here, the adaptive modulation control means uses as the threshold value a value of the line quality at the intersection of two curves indicating the aforementioned characteristic under a condition having no disturbance among the plurality of modulation encoding methods.

Abstract: Apparatus and method for generating first, second and third carrier frequencies of 3432 MHz, 3960 MHz and 4488 MHz respectively, for use in a wireless transmission system deploy only first and second PLLs which are configured to generate 6336 MHz and 2640 MHz signals respectively with only in-phase components. Frequency dividers are employed for frequency-dividing the 6336 MHz signal severally by 2, 4, and 12 to obtain frequency-divided intermediate outputs with both in-phase and quadrature components. The intermediate output components and other intermediate signal components are selectively combined in a mixer (e.g., a single side-band mixer), for deriving the first, second and third carrier frequencies of 3432 MHz, 3960 MHz and 4488 MHz with both in-phase and quadrature components. The invention has application in UWB, WPAN, WLAN, or other wireless systems and has the simplicity and advantages of using only two PLLs instead of the prior art arrangements of three PLLs.

Abstract: An embodiment of the present invention provides a method, comprising using a predetermined limited set of modulation patterns to perform adaptive bit loading (ABL) to compress the modulation patterns in wireless communications.

Abstract: This disclosure describes companded transmit path techniques that may be implemented in a wireless communication device to reduce power consumption and possibly simplify signal modulation. In accordance with this disclosure, in phase (I) and quadrature phase (Q) components of a transmit waveform are compressed at baseband, and an emphasis envelope is generated to represent this compression. The compressed I and Q components are then converted to analog signals and processed. This analog processing may include the mixing process in which the compressed I and Q signals are modulated onto a carrier waveform. The emphasis envelope signal is then used to expand the modulated waveform.

Abstract: The present invention relates to a method in a transmitter for interleaving information bits from a data block into transmission bursts. Each of the information bits is assigned with an index. The interleaving includes computing positions of the information bits in the transmission bursts such that the values of the indexes of at least a portion of the information bits are modified. At a receiver it is determined if the value of any of the indexes has been modified before transmission of the transmission bursts. Based on the determination, de-interleaving of the information bits is then accomplished based on modified values of the indexes or originally assigned values of the indexes.

Abstract: Disclosed are a wireless communication apparatus, a wireless communication method, and a computer program for intercommunication between a plurality of wireless stations. In a reception standby state, packet detection is performed by using a part of the plurality of reception branches to disable the reception operation of the remaining reception branches that do not perform packet detection, and thereby reducing the power consumption during packet detection standby. Further, in a packet reception state, only the minimum necessary number of reception branches for receiving signal that is spatially multiplexed is enabled by MIMO transmission, and thereby reducing the power consumption also during reception of MIMO signals.

Abstract: An interleaver and interleaving method each includes two stages, and is useful in coded orthogonal frequency division multiplexed (COFDM) wireless local area networks. A first stage performs a first block permutation and a second stage performs bit order permutation to effectuate a second group permutation. A corresponding de-interleaver does just the opposite at the receiver. A double-buffer version includes writing data into one memory block in a first order while reading data from the second block in a second order, with the first and second orders selected to effectuate the first block permutation.

Abstract: Systems and methods for bidirectional communication are provided. In one embodiment, a method for aligning communications from a plurality of remote units in a multipoint-to-point orthogonal frequency division multiplexed (OFDM) communications comprises sending a first signal from a host unit to a first remote unit; receiving a second signal transmitted from the first remote unit in response to the first signal; generating at least one timing adjustment signal based at least in part on a round trip delay between the sending of the first signal and the receiving of the second signal; transmitting the timing adjustment signal to the first remote unit; wherein the timing adjustment signal instructs the first remote unit to delay OFDM transmission of data to improve alignment of multiframes at the host unit when communications are received at the host unit from the plurality of remote units.

Abstract: A transmitter for sending signals over wireless channels and a method of sending signals over wireless channels are described. The transmitter and the method are used to determine a transfer characteristic of an amplifier (8) in the transmitter. Symbols in the OFDM signals to be transmitted are multiplied by test signals at predefined points in time to compare the OFDM symbol, which has been multiplied by the test signal, upstream and downstream from the amplifier to determine the transfer characteristic of the amplifier (8). This transfer characteristic of the amplifier (8) is used by a predistorter (4) to predistort the signals according to this transfer characteristic. The test signal, which is generated by a signal generator (13), is input into a symbol of the fast information channel, the test signal having an amplitude which drives the multiplied symbol into the saturation range of the amplifier (8) with regard to its amplitude.

Abstract: The invention performs orthogonal frequency division multiplex processing on a transmission signal to form an OFDM modulation signal (daubed in FIG.) and performs orthogonal frequency division multiplex processing and code division multiple access processing on a transmission signal to form an OFDM-CDM modulation signal (shaded in FIG.) to transmit the OFDM modulation signal and the OFDM-CDM modulation signal, which makes it possible to transmit data in a very high rate using the OFDM modulation signal while making it possible to transmit data in a higher quality using the OFDM-CDM modulation signal than using the OFDM—modulation signal, although it is slightly inferior to OFDM modulation in terms of high rate transmission.

Abstract: A method and apparatus for transmitting and receiving MAP information in a communication system are provided. A base station acquires channel quality information of each mobile station, generates sub-MAPs using MAP information, to which at least one of a coding scheme, a modulation scheme and a repetition scheme is applied, separately for each mobile station according to the channel quality information, and transmits the generated sub-MAPs. A mobile station receives MAP information from the base station, detects a sub-MAP allocated to the mobile station from the received MAP information, and restores the detected sub-MAP to MAP information using at least one of a corresponding decoding scheme, demodulation scheme and repetition scheme corresponding to coding scheme, modulation scheme and repetition scheme applied in the base station, based on channel quality information of the mobile station. Accordingly, system overhead can be reduced.

Abstract: Methods for orderwire modulation are provided. In one embodiment, a method for an orthogonal frequency division multiplexing multipoint-to-point communications system comprises: establishing communication between a first remote unit of a plurality of remote units and a host unit, the plurality of remote units communicatively coupled to the host unit in a multipoint-to-point configuration; transmitting non-control data on up to a plurality of tones from the first remote unit using an orthogonal frequency division multiplexing (OFDM) waveform, the up to a plurality of tones modulated with the non-control data using a first modulation scheme; and transmitting control signals on up to a plurality of tones from the first remote unit using an orthogonal frequency division multiplexing (OFDM) waveform, the up to a plurality of tones modulated with the control signals using a second, more robust modulation scheme.

Abstract: A wireless communication system and a detect-and-multiplex (DAM) spectrum sharing technique eliminate contention by secondary spectrum users by multiplexing multiple access methods. Suitable multiple access methods include time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA), space division multiple access (SDMA), orthogonal frequency division multiple access (OFDMA), spectral nulling (SN) or a hybrid scheme (HS) based on a combination of two or more of the above techniques. Unlike, detect-and-avoid (DAA) multiple access methods, the DAM method increases spectrum usage efficiency, and allows more users to share the same region of the spectrum.

Abstract: The invention relates to a method and to a modulator for modulating signals. The signals are to be transmitted by a device in packets via an air interface. Each packet is supposed to comprise at least one entity of at least two different entities, which different entities are employed for transmitting signals representing different kinds of information. In order to enable a higher data rate, signals that are to be transmitted in at least one of said different entities are modulated with a first set of values of at least one modulation parameter of a selected modulation scheme. Further, signals that are to be transmitted in at least one other of said different entities are modulated with a second set of values of said at least one modulation parameter, said second set of values comprising less values than said first set of values.

Abstract: Whether to abort reception of a multi-part message in a code division multiple access communication system is determined by receiving a part of the multi-part message. Correlating the received part of the multi-part message with a known sequence generates a correlation value. The correlation value is compared with a threshold level. Reception of the multi-part message is aborted if the correlation value is less than a threshold level. In another aspect, the threshold level is dynamically adjusted based on a communication traffic behavior. The communication traffic behavior may be, for example, whether traffic directed to a particular user equipment (UE) is part of a burst directed to that UE.

Abstract: A system for transmitting information as frames in digital format between users on a network using a single frequency and TDMA and/or CDMA communications. Broadcasting, multicasting and unicasting are provided, and communications may be part of a downlink and/or an uplink signaling scheme that allows user-user and user-central station communication. A synchronization segment or pre-amble for a frame may include identification of the source and/or the intended recipient. Walsh, Haar, Rademacher coding of selected frame components, among others, can be incorporated. Reed Solomon encoding, signal interleaving and intra-leaving, trellis encoding and turbo encoding are used for error detection and correction. The system provides two-way communication with the Internet and/or with a cellular network and/or for smaller networks of users.

Abstract: In a communication system, when packet data units (PDUs) to be transmitted from a transmitter apparatus are modulated according to Orthogonal Frequency Division Multiplexing (OFDM), the waveforms representing the modulated PDUs will experience different peak to average ratio values (PAR) making the PDUs differently sensitive to non-ideal transmitter characteristics. To minimize errors in the transmitted PDUs, at least two PDUs (304, 305, 306) are scrambled and modulated in parallel and substantially simultaneously in the transmitter (100), and the PAR values of the at least two PDUs (304, 305, 306) are determined at each transmit instance. The measured PAR values of the at least two PDUs are compared in a scheduler (310), and the scheduler selects for transmission the PDU with the lowest PAR value. The scheduler (310) then instructs the transmitter (100) to transmit the selected PDU.

Abstract: A method and system for wireless data communication using a first wireless communication technology and a second wireless communication technology. The second wireless communication technology being different from the first wireless communication technology. A transmitter is arranged to transmit data using frame structures based on the first wireless communication technology and the second wireless communication technology in which the frame structure based on the second wireless communication technology has a timing structure, MAC and pilot that are also used with the frame structure of the first wireless communication technology. The transmitter is arranged to selectively change transmission on a frame by frame basis between the first wireless communication technology and the second wireless communication technology.

Abstract: Methods and systems for adaptive modulation are provided. In one embodiment, a method for a plurality of remote units of an orthogonal frequency division multiplexing multipoint-to-point communications system comprises: establishing communication between a plurality of remote units and a host unit, the plurality of remote units communicatively coupled to the host unit in a multipoint-to-point configuration; transmitting a plurality of tones from the plurality of the remote units such that tones from more than one remote unit are simultaneously received at the host unit, the plurality of tones modulated with upstream information using orthogonal frequency division multiplexing; modulating up to a plurality of tones using a first modulation scheme when transmitting a first type of upstream information; and modulating up to a plurality of tones using a second modulation scheme when transmitting a second type of upstream information.

Abstract: Methods and systems for forward-looking tone allocation are provided. In one embodiment, a method for an orthogonal frequency division multiplexing (OFDM) multipoint-to-point communications system comprises: establishing communication between a plurality of remote units and a host unit, the remote units communicatively coupled to the host in a multipoint-to-point configuration; transmitting a plurality of tones from the remote units, such that tones from more than one remote unit are simultaneously received at the host, the tones modulated with upstream information using OFDM; adjusting at least one characteristic of at least one tone at least one remote unit, in response to adjustment commands from the host, such that the orthogonality of the simultaneously received tones is improved as received at the host unit; and dynamically switching modulation from at least a first tone of the plurality of tones to a second tone based on an error-rate history of the second tone.

Abstract: Wireless communication systems are provided with an adaptive subcarrier loading function for a mobile receiver in a wireless communication system based on Orthogonal Frequency Division Multiplexing (OFDM) that can advantageously be applied to predict the channel transfer function of a multipath propagation channel being severely impaired by frequency-selective fading and an extremely time-variant behavior by detecting the position and/or movement of zero points of the transfer function, thereby reducing the probability of incorrect assignment of the modulation scheme for each subcarrier caused by mobile terminals moving at high velocity. The zero points of the estimated channel transfer function are determined by detecting the position of deep notches on the associated amplitude response of the measured channel transfer function caused by frequency-selective fading whose depths are larger than a predefined threshold.

Abstract: A system for using a plurality of processors to support a media conference includes a mixing processor and a first media transformation processor coupled to the mixing processor. The mixing processor mixes input media information associated with two or more first participants to generate output media information for communication to a second participant. The first media transformation processor receives the output media information from the mixing processor, encodes the output media information to generate an output data stream, and communicates the output data stream to the second participant's end-user device.

Abstract: Disclosed is a transmitting and receiving method for reducing a time-varying channel distortion in an orthogonal frequency division multiplex (OFDM) system. In the present invention, the transmitter defines M sub-channels in one data group, mathematically analyzes a change of channel for each path causing a time-varying channel distortion in a high-speed mobile environment by approximation, calculates a weight value based on the mathematical analysis and assigns the calculated weight value to transmit data of each sub-channel. Subsequently, the receiver combines the signals of these M sub-channels and demodulates the combined signals. Accordingly, the present invention greatly reduces a distortion caused by the time-varying channel to improve a bit error rate and a channel estimation performance.

Abstract: A system and method for synchronous spectrum sharing for use in a wireless communication system based on orthogonal frequency-division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) signaling is disclosed. The system includes a frame detector configured to detect a frame of a broadcast waveform and extract sub-carrier information from the frame. Sub-carrier information may include information on usable sub-carrier and pilot sub-carriers for secondary users. The system allows transmitting data from the secondary user node in unused sub-carriers thereby making efficient use of unused or idle spectrum. Accordingly, secondary users of wireless communication systems can dynamically form ad-hoc mesh network communications in fixed or mobile scenarios.

Abstract: The available modulation schemes of a network are analyzed to determine which ones contain excessive phase noise or narrowband interference. A network element is selected and assigned to a test channel at a first modulation scheme at a predetermined power level to achieve a predetermined PER. The network element transmits a test signal and the network controller measures the signal to noise ratio (SNR) in the received test signal. If the SNR is not within a predetermined tolerance range of an estimated SNR for the modulation scheme at the predetermined PER, the modulation scheme is determined to have excessive phase noise or narrowband interference. Each available modulation scheme is tested by instructing the network element to transmit the test signal using each modulation scheme and assigning the power level of each modulation scheme. The suitable modulation schemes may be determined.

Abstract: An apparatus and method for communicating control information in a Broadband Wireless Access (BWA) system using a multi-hop relay scheme is provided. A method of transmitting control information includes generating scheduling information by performing scheduling for a Relay Station (RS); determining a valid duration for the scheduling information; generating a resource allocation message containing the scheduling information and the valid duration information; and processing the resource allocation message in a physical layer and for transmitting the resource allocation message to the RS.

Abstract: Described is a communication system including mobile communication devices. In the described system, the mobile devices may be wrist-worn watches such as are in common use today, except that the watches are specially configured to receive data in a “broadcast” mode and transmit and/or receive data in a “localcast” mode. The localcast mode includes the ability to transmit and receive data in a peer-to-peer fashion, allowing mobile devices to communicate directly with each other. The ability to combine two of these communication modes in a small, integrated and hence inexpensive and low-power package provides many advantages over existing personal communication device solutions.

Abstract: An IC card system for transceiving data signal between an IC card processor and an IC card in the manner of non-contact are provided. The IC card modulates the signal to be transmitted to the processor in the manner of Quadrature Amplitude Modulation and generates the modulated signal. A card reader demodulates the signal received from the IC card in the manner of QAM. The rate of the data signal transmitted from the IC card to the card reader is improved.

Abstract: This disclosure describes content-adaptive coding and modulation techniques. In particular, this disclosure describes techniques in which both a multimedia coding mode and a physical layer modulation scheme are adaptively selected based on content of a multimedia sequence. When the content changes such that either the coding or the modulation scheme can be improved, the coding and/or modulation may be changed to better optimize to the changed content. In one aspect, this disclosure provides a method of processing multimedia data, the method comprising selecting a multimedia coding mode for an encoder to encode the multimedia data and a physical layer modulation scheme for transmission of the multimedia data based on content of the multimedia data.

Abstract: A radio relay system (1) comprises a wireless camera (11) and a signal receiving relay station (12). The wireless camera (11) wirelessly transmits signals to the signal receiving relay station (12) by using the OFDM modulation method. The wireless camera (11) and the signal receiving relay station (12) perform energy dispersion at the time of transmission-line-coding/decoding a transport stream. The PRBS seed (initial value) to be used for the energy dispersion can be externally modified and the user can arbitrarily select a value for the seed.

Abstract: A Hybrid IMMSE-LMMSE receiver processing technique predicts performance of and selects between iterative and non-iterative decoding of symbols based on an intelligent metric. Based on a pre-specified criterion, the receiver determines if a correct first-stage decision is made or not. If a correct decision is made, then it follows iterative processing like in BLAST. Alternatively, if a wrong decision is found to have occurred, the receiver resorts to LMMSE estimation processing.

Abstract: Embodiments of a radio link control media access control module and associated methods may be described herein. Other embodiments may be described and claimed.

Abstract: The invention relates to the preparation and numerical optimization of non-linear space-time block codes for application in a digital mobile radio system, with a maximum transmission diversity for “Rate 1,” transmission systems in the case of two or more transmitter antennae and with complex symbols.

Abstract: An OFDM demodulator includes an FFT circuit, a phase correction circuit, and a timing synchronization circuit. The timing synchronization circuit includes a symbol-boundary calculation circuit to estimate a symbol-boundary position Nx by filtering the correlation peak of a guard interval, symbol-boundary correction circuit to calculate a clock-phase error based on the symbol-boundary position Nx, and a start-flag generation circuit to generate a start flag for the FFT calculation. The symbol-boundary correction circuit subtracts only a value whose precision is smaller than the cycle of a reference clock from the symbol-boundary position Nx, and generates a phase correction signal for each sub-carrier based on the value. The phase correction circuit performs a complex multiplication of the FFF-calculated signal by the phase correction signal to correct the clock-phase error.

Abstract: A system for implementing a base band compression scheme for a nonlinear multiplying up-converter for QPSK and OQPSK includes a bit combining module, a quadrant remap module, a look-up table (LUT) and a zoom adjust module. The bit combining module is configured to generate an address based on a number of symbols received as input data. Using the address provided by the bit combining module, the quadrant remap module remaps symbols from quadrants “2”, “3” and “4” to quadrant “1” and generates signals to look up corresponding output data from the LUT. The zoom adjust module generates a number of solutions corresponding to the input data using the corresponding output data retrieved from the LUT. The zoom adjust module is then used to select the best output from the solutions to provide a smooth output signal that does not have any discontinuities.

Abstract: A dual packet configuration for wireless communications including a first portion that is modulated according to a serial modulation and a second portion that is modulated according to a parallel modulation. The serial modulation may be DSSS whereas the parallel modulation may be OFDM. The first portion may include a header, which may further include an OFDM mode bit and a length field indicating the duration the second portion. The first portion may be in accordance with 802.11b to enable dual mode devices to coexist and communicate in the same area as standard 802.11b devices. The dual mode devices can communicate at different or higher data rates without interruption from the 802.11b devices. The packet configuration may include an OFDM signal symbol which further includes a data rate section and a data count section. In this manner, data rates the same as or similar to the 802.11a data rates may be specified between dual mode devices.

Abstract: Methods and systems for transmitting a modulated frame in a block transmission system and for decoding the modulated frame when received are provided. The block transmission system is a frequency reuse system. The transmission of a frame in a block transmission system includes modulating the frame using a modulation sequence to produce a modulated frame and transmitting the modulated frame. The modulation sequence is unknown to a receiver that will receive the modulated frame, and is representative of control information.

Abstract: In LMDS systems the downlink bandwidth is continuously varying in time because each downlink burst uses a network termination individual modulation and coding (Physical layer) scheme, the higher layer (IP) functions cannot perform service priority respecting traffic shaping. The invention proposes mainly to combine both framing and IP layer functions within one inter-layer framer. The combination of both information ensures QoS provisioning in case of multi-modulation and multi-coding environment. The QoS queue server gets always informed on the actual amount of available data frame bits from the downlink framer and therefore, the QoS queue server is able to decide on the next IP packet or packet fraction to transport. This decision is always based on service priority aspects. As soon as the downlink frame is filled—supposing that the maximum downlink frame rate is always lower than the internal processing in the inter-layer framer—the QoS server stops the data delivery.

Abstract: An input digital signal is periodically and alternately subjected to first modulation and second modulation, being thereby converted into a pair of a baseband I signal and a baseband Q signal. The first modulation and the second modulation are different from each other. The pair of the baseband I signal and the baseband Q signal are outputted. The first modulation may be at least 8-signal-point modulation while the second modulation may be phase shift keying.

Abstract: An apparatus and method for determining an optimum modulation scheme and code rate in a communication system using a variable transmission scheme. In a transmitter included in the communication system, an encoder encodes an encoder packet (EP) and a plurality of modulators having different modulation orders modulate sub-packets being codewords output from the encoder. A selector selects one of the modulators by comparing an MPR (Modulation order Product code Rate) being a ratio of an EP size to a number of payload modulation symbols, and comparing the MPR with a threshold.

Abstract: The present invention involves a method and system for transmitting two levels of data in a hierarchical transmission schema. A first modulated signal is generated based on first input. A second modulation signal is generated based on a second input that has a data rate that is a fraction of the data rate of the first modulated signal. The second modulation signal has known instances where the second modulation signal has no energy. In a system where the first modulation is quadrature phase shift keying (QPSK), the second modulation signal can be a secondary phase offset. A receiver in the system that has a priori knowledge about the timing relationship between the first data signal and the instances when the second data signal is present will be able to detect both data signals optimally.

Abstract: A code-enhanced, multi-user detection, Reduced Algorithm Receiver in a multiuser communication system reduces the signal processing requirements by limiting the number of searches between consecutive symbol cycles using information from an encoder state diagram. The Receiver makes use of a convolutional encoder's state machine properties to mark possible transitions as invalid based on the current state of the multiple users'encoders, thus removing them from the search tree.

Abstract: A regenerated data signal generation circuit includes a receiving circuit, first and second binarization circuits and a signal preparation circuit. The receiving circuit receives a modulated signal and demodulates the modulated signal. The first binarization circuit receives the demodulated signal and binarizes the demodulated signal while compensates for offset deviation of the demodulated signal by a first method as to output a first binarization signal. The second binarization circuit receives the demodulated signal and binarizes the demodulated signal while compensates for offset deviation of the demodulated signal by a second method that is different from the first method so as to output a second binarization signal. The signal preparation receives the first and second binaraization signals and selectively outputs a regenerated data signal prepared from one of the binarization signals.

Abstract: The invention relates to a network comprising a plurality of terminals. A transmitting terminal selects a modulation method in a first step at the beginning of a data transmission in which method a maximum permitted packet error rate for an estimated received-user-signal-to-noise-power ratio is remained under. In a second step the transmitting terminal determines the transmission power which is produced for a desired packet error rate for the modulation method selected in the first step.