Abstract: Method and apparatus for generating codewords with variable length and redundancy from a single Low-Density Parity-Check (LDPC) code with variable length input words. A mother code for encoding data words is generated based on a parity-check matrix, wherein the mother code is adjusted to reflect the size of the data word to be encoded. A generator matrix applies the mother code to data words to produce codewords for transmission. In one embodiment, a reduction criteria is determined and the size of the generator matrix reduced in response. The corresponding parity-check matrix is applied at the receiver for decoding the received codeword.

Abstract: In a disclosed embodiment, signal levels of the active sectors of an access terminal are compared with the signal level of the current serving sector of the access terminal. Next, a delta credit is accumulated. If a DRC lock bit is available, then an accumulated total credit is authorized to produce an authorized accumulated total credit. Afterwards, a new serving sector is identified from a pool of candidate sectors based on the signal levels of the active sectors and the authorized accumulated total credits.

Abstract: An optimum combiner that reduces the amount of interference imposed upon a first base station by transmissions of other base stations within the same communication system. Two antennas are used to receive transmissions within a receiving station. A rake receiver is coupled to each antenna. By optimally combining the signals that are received by each independent finger of the rake receiver, interference that is correlated between a finger associated with the first antenna and a finger associated with the second antenna can be minimized with respect to the desired signal. Optimum combining requires determination of optimum combining coefficients.

Abstract: A method and an apparatus for waveform quality measurement are disclosed. An actual signal, representing a waveform channelized both in time and in code is generated by, e.g., an exemplary HDR communication system. Test equipment generates an ideal waveform corresponding to the actual waveform. The test equipment then generates an estimate of offsets between parameters of the actual waveform and the ideal waveform, and the offsets are used to compensate the actual waveform. The test equipment then evaluates various waveform quality measurements utilizing the compensated actual waveform and the corresponding ideal waveform. Definitions of the various waveform quality measurements as well as conceptual and practical examples of processing of the actual waveform and the corresponding ideal waveform by the test equipment are disclosed. The disclosed method and apparatus may be extended to any waveform channelized both in time and in code regardless of the equipment that generated the waveform.

Abstract: In a disclosed embodiment, signal levels of the active sectors of an access terminal are compared with the signal level of the current serving sector of the access terminal. Next, a delta credit is accumulated. If a DRC lock bit is available, then an accumulated total credit is authorized to produce an authorized accumulated total credit. Afterwards, a new serving sector is identified from a pool of candidate sectors based on the signal levels of the active sectors and the authorized accumulated total credits.

Abstract: Systems and techniques for gain control include amplifying a signal with an amplifier having a gain represented by one of a plurality of gain curves depending on a value of a parameter, the signal being amplified at a first one of the parameter values, and controlling the gain of the amplified signal from a predetermined gain curve relating to the gain curve of the amplifier for a second one of the parameter values by adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of the first one of the parameter values, and applying the adjusted gain control signal to the amplifier. 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.

Abstract: Methods and apparatus for estimating maximum rate of data and for estimating a transmission power required for transmission of a data with a rate of data in a communication system are disclosed. A terminal determines a quality metric of a communication link, over which data are to be transmitted, and modifies the determined quality metric by a quality metric margin. The terminal then estimates the maximum rate of data in accordance with the modified quality metric. Alternatively, the terminal then estimates transmission power required for transmission of a data with a rate of data in accordance with the rate of data and the modified quality metric. The quality metric margin may be a pre-determined or dynamically adjusted. The terminal dynamically adjusts the quality metric margin in accordance with a result of comparison of a transmit power corresponding to the estimated maximum rate of data with an actual transmit power used to transmit the data.

Abstract: A method and apparatus for computing soft decision input metrics to a turbo decoder includes circuits associated with eight-ary phase shift keyed (8PSK) modulation and sixteen-ary quadrature amplitude modulation (16QAM). In both implementations log-likelihood ratio (LLR) metrics on code symbols are estimated as products of various constant values and various combinations of the in-phase and quadrature components of a demodulated soft decision. In the implementation associated with the 16QAM modulation scheme, an estimate of the carrier-signal-to-interference (C/I) ratio is also used to estimate some of the LLR metrics. Estimates of the LLR metrics may also be obtained in association with generalized square QAM and M-ary PSK modulation schemes including, e.g., 64QAM, 256QAM, and 16PSK.

Abstract: Systems and techniques for controlling transmission power involve receiving a first to second channel power ratio, receiving a first to second channel power ratio, adjusting the power ratio if a combined power of a plurality of channels exceeds a threshold, the channels including the first and second channels, and computing gain of the first channel as a function of the power ratio. 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 techniques for controlling transmission power involve receiving a first to second channel power ratio, receiving a first to second channel power ratio, adjusting the power ratio if a combined power of a plurality of channels exceeds a threshold, the channels including the first and second channels, and computing gain of the first channel as a function of the power ratio. 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: In a disclosed embodiment, signal levels of the active sectors of an access terminal are compared with the signal level of the current serving sector of the access terminal. Next, a delta credit is accumulated. If a DRC lock bit is available, then an accumulated total credit is authorized to produce an authorized accumulated total credit. Afterwards, a new serving sector is identified from a pool of candidate sectors based on the signal levels of the active sectors and the authorized accumulated total credits.

Abstract: In a transmission scheme wherein multi-slot packet transmissions to a remote station can be terminated by an acknowledgment signal from the remote station, code symbols can be efficiently packed over the multi-slot packet so that the remote station can easily decode the data payload of the multi-slot packet by decoding only a portion of the multi-slot packet. Hence, the remote station can signal for the early termination of the multi-slot packet transmission, which thereby increases the data throughput of the system.

Abstract: In one embodiment, the invention is directed toward techniques for generating results in a logarithmic domain. The techniques may exploit properties of a logarithmic function to reduce the memory requirements needed to implement lookup tables. For example, the techniques may utilize non-uniform sampling over a logarithmic or logarithmic-like function to reduce the number of entries needed for a given lookup table. In particular, the techniques may involve separating a number into an exponent component and a mantissa component. Each of these different components can then be converted from a first domain to a second domain using different lookup tables.

Abstract: Techniques to adjust the setpoint of a power control loop in a wireless communication system. The setpoint may be adjusted based on frame status indicative of erased/good decoded frames, one or more (typically soft) metrics indicative of the confidence in the decoded results, power surplus/deficit indicative of the difference between the received signal quality and the setpoint, setpoint surplus/deficit indicative of the difference between the setpoint and a threshold Eb/Nt needed for the desired level of performance, or a combination thereof. The metrics may include re-encoded symbol error rate, re-encoded power metric, modified Yamamoto metric, minimum or average LLR among decoded bits, number of decoding iterations, and possibly others. The setpoint may be adjusted in different manners and/or by different amounts depending on the above-noted factors. The techniques may be employed for forward and/or reverse links in CDMA systems.

Abstract: A method and an apparatus for waveform quality measurement are disclosed. An actual signal, representing a waveform channelized both in time and in code is generated by, e.g., an exemplary HDR communication system. Test equipment generates an ideal waveform corresponding to the actual waveform. The test equipment then generates an estimate of offsets between parameters of the actual waveform and the ideal waveform, and the offsets are used to compensate the actual waveform. The test equipment then evaluates various waveform quality measurements utilizing the compensated actual waveform and the corresponding ideal waveform. Definitions of the various waveform quality measurements as well as conceptual and practical examples of processing of the actual waveform and the corresponding ideal waveform by the test equipment are disclosed. The disclosed method and apparatus may be extended to any waveform channelized both in time and in code regardless of the equipment that generated the waveform.

Abstract: A power control system for controlling the transmission power in a system wherein the transmission power may be gated or capped. The receiver employs a combination of closed loop and outer loop power control. The outer loop is frozen upon detection by the receiver that the signal has been capped or gated.

Abstract: A power control system for controlling the transmission power in a system wherein the transmission power may be gated or capped. The receiver employs a combination of closed loop and outer loop power control. The outer loop is frozen upon detection by the receiver that the signal has been capped or gated.

Abstract: An optimum combiner that reduces the amount of interference imposed upon a first base station by transmissions of other base stations within the same communication system. Two antennas are used to receive transmissions within a receiving station. A rake receiver is coupled to each antenna. By optimally combining the signals that are received by each independent finger of the rake receiver, interference that is correlated between a finger associated with the first antenna and a finger associated with the second antenna can be minimized with respect to the desired signal. Optimum combining requires determination of optimum combining coefficients.

Abstract: An optimum combiner that reduces the amount of interference imposed upon a first base station by transmissions of other base stations within the same communication system. Two antennas are used to receive transmissions within a receiving station. A rake receiver is coupled to each antenna. By optimally combining the signals that are received by each independent finger of the rake receiver, interference that is correlated between a finger associated with the first antenna and a finger associated with the second antenna can be minimized with respect to the desired signal. Optimum combining requires determination of optimum combining coefficients.