摘要:
A simultaneous multiple channel receiver (“SMCR”) for receiving a combined signal having a plurality of carrier signals, where each carrier signal in the plurality of carriers signals corresponds to a frequency channel, and in response, simultaneously producing a plurality of output data stream signals, is disclosed. The SMCR may include a down-converter front-end capable of receiving the combined signal, a plurality of digital signal processors, wherein each digital signal processor of the plurality of digital signal processors is capable of producing an output data stream signal of the plurality of output data stream signals, and a multi-band filter in signal communication with both the down-converter front-end and the plurality of digital signal processors.
摘要:
A power amplifier that amplifies an electrical signal that is passed through a power amplification array. The power amplifier is employed in various applications including cellular telephones, radio frequency signal transmission, and other electrical signal applications requiring power amplification. The power amplifier contains a number of power amplifiers arranged in a power amplifier array. To reproduce a particular envelope profile, a selected number of the power amplifiers of the power amplifier array is switched ON, whereas another selected number of the power amplifiers of the power amplifier array are switched OFF. All elements are fed with an RF signal containing phase information as well. The amplified, output signal provided after the power amplifier array is fed to an antenna for signal transmission. Impedance matching circuitry is employed between the power amplifier array and the antenna to provide efficiency for those applications having low power budgets or seeking to operate with extremely high efficiency. The present invention provides a solution that is extremely energy efficient, making it ideally suited for applications having low available power budgets such as battery operated devices such as cellular telephones. From one perspective, the power amplifier array is operated as if it were a digital device. For example, each of the individual power amplifiers of the power amplifier array is either switched ON or switched OFF, as described above, and a selected number of the power amplifiers provides the desired level for the specific application.
摘要:
Iterative decoder employing multiple external code error checks to lower the error floor and/or improve decoding performance. Data block redundancy, sometimes via a cyclic redundancy check (CRC) or Reed Solomon (RS) code, enables enhanced iterative decoding performance. Improved decoding performance is achieved during interim iterations before the final iteration. A correctly decoded CRC block, indicating a decoded segment is correct with a high degree of certainty, assigns a very high confidence level to the bits in this segment and is fed back to inner and/or outer decoders (with interleaving, when appropriate) for improved iterative decoding. High confidence bits may be scattered throughout inner decoded frames to influence other bit decisions in subsequent iterations. Turbo decoders typically operate relatively well at regions where the BER is high; the invention improves iterative decoder operation at lower BERs, lowering the ‘BER floor’ that is sometimes problematic with conventional turbo decoders.
摘要:
Iterative decoder employing multiple external code error checks to lower the error floor and/or improve decoding performance. Data block redundancy, sometimes via a cyclic redundancy check (CRC) or Reed Solomon (RS) code, enables enhanced iterative decoding performance. Improved decoding performance is achieved during interim iterations before the final iteration. A correctly decoded CRC block, indicating a decoded segment is correct with a high degree of certainty, assigns a very high confidence level to the bits in this segment and is fed back to inner and/or outer decoders (with interleaving, when appropriate) for improved iterative decoding. High confidence bits may be scattered throughout inner decoded frames to influence other bit decisions in subsequent iterations. Turbo decoders typically operate relatively well at regions where the BER is high; the invention improves iterative decoder operation at lower BERs, lowering the ‘BER floor’ that is sometimes problematic with conventional turbo decoders.
摘要:
A method and apparatus for processing demodulated data comprising received symbol data is disclosed. A decoder is used to compute estimated symbols and corresponding reliability metrics. The reliability metrics are transformed into reliability weights. Optionally, residuals relating to the difference between the received symbol data and the estimated symbols are computed. Output data are generated comprising any combination of the following: estimated symbols, reliability weights, residuals, and received symbol data. The residuals may be weighted by the reliability metrics and used by demodulation or error compensation loops to instantaneously reduce or increase the bandwidth of these loops.
摘要:
A method for estimating an SNR-related parameter, such as ES/N0, from one or more symbols. The number of symbols within a predetermined number of symbols that fall within one or more collection areas is counted. The count is then associated with a value of the SNR-related parameter. This association may be performed through one or more lookup tables. In one application, a scaling factor is derived from the count. The scaling factor may be used to scale symbols before they are quantized and inputted into a trellis decoder such as a log-MAP decoder.
摘要翻译:一种用于从一个或多个符号估计SNR相关参数的方法,例如E / S / N 0 0。 计数落入一个或多个收集区域内的预定数量的符号内的符号数。 然后计数与SNR相关参数的值相关联。 该关联可以通过一个或多个查找表来执行。 在一个应用中,从计数导出缩放因子。 比例因子可以在量化之前对符号进行缩放并输入到诸如log-MAP解码器的网格解码器中。
摘要:
A method and system are described for assigning reliability metrics to error correction coded bits or symbols that are decoded. Survivor and non-survivor paths through a portion of a trellis representation within a sliding window are determined and recorded. Primary and non-primary traceback paths through a portion of the trellis representation are determined from the recorded data. If the primary and non-primary traceback paths diverge at a release point, a reliability metric is assigned to the bit or symbol estimate corresponding to the release point. This metric is derived from the difference between the path metrics of the primary and non-primary traceback paths. Alternately, if the two paths diverge through all or a portion of a release zone, a reliability metric is assigned to the block of bit or symbol estimates corresponding to the portion or more of the release zone where the two paths diverge from one another. Again, this metric is derived from the difference between the path metrics of the primary and non-primary traceback paths.
摘要:
A decoder having a first decoder providing first decoded data. A deinterleaver is included for deinterleaving the first decoded data. A second decoder provides second decoded data based on the deinterleaved first decoded data. The second decoder provides at least one decode status signal indicative of second decoder operations. A pipeline decoder unit is included that is coupled to the second decoder. The pipeline decoder unit includes an encoder that receives the second decoded data and provides forced decision data, a multiplexer, and a third decoder that provides pipelined decoded data. The multiplexer is responsive to the at least one decode status signal to selectively constrain the pipelined decoded data to be at least partially dependent on the forced decision data.
摘要:
An exemplary satellite communication system comprises a service provider unit communicably coupled to a number of subscriber units via satellite transmission. The service provider unit includes an encoder configured to encode source data into a serial transmit sequence, and is further capable of supporting at least two modes of operation. The serial transmit sequence includes a first unique word identifying a first mode of operation, and is followed by a first payload packet having a first number of channel symbols corresponding to a source packet encoded in accordance with the first mode of operation identified by the first unique word. The first payload packet is encapsulated by two unique words and the time interval between the two unique words is used to determine the first mode of operation identified by the first unique word.
摘要:
An iterative system for performing carrier phase tracking of symbols using a serial turbo decoder. Estimates of a buffered block of symbols are provided by a serial turbo decoder. Optionally, reliability metrics for the estimates are provided as well. Responsive to this information, a tracking loop module determines derotation phases for each of the symbols in the buffer. A symbol derotator derotates each of the buffered symbols in the block by its corresponding derotation phase. The derotated symbols are stored back in the buffer. The process may repeat itself for a prescribed number of iterations, after which the serial turbo decoder provides estimates of the underlying source bits.