Abstract: An apparatus for determining the presence of a tone in an input signal includes memory circuitry and data processing circuitry coupled to the memory circuitry. The data processing circuitry is operative to receive multiple samples of the input signal, and to determine a first value at least in part by multiplying each of the samples by respective ones of a first set of values for an impulse response and summing the results. The data processing system is also operative to determine a second value at least in part by multiplying each of a portion of the samples by respective ones of a second set of values for the impulse response and summing the results. The data processing system is operative to determine the power of the tone in the multiple samples of the input signal at least in part by utilizing the first value and the second value.

Abstract: An apparatus for determining the presence of a tone in an input signal includes memory circuitry and data processing circuitry coupled to the memory circuitry. The data processing circuitry is operative to receive multiple samples of the input signal, and to determine a first value at least in part by multiplying each of the samples by respective ones of a first set of values for an impulse response and summing the results. The data processing system is also operative to determine a second value at least in part by multiplying each of a portion of the samples by respective ones of a second set of values for the impulse response and summing the results. The data processing system is operative to determine the power of the tone in the multiple samples of the input signal at least in part by utilizing the first value and the second value.

Abstract: A method of detecting received data in a communication system includes the steps of: performing a QR decomposition on a received input vector as a function of one or more characteristics of a communication channel over which the input vector was transmitted; generating a subset of best symbol candidates from a symbol constellation by comparing an input sample (corresponding to an element of the input vector) with one or more prescribed thresholds; identifying at least one symbol satisfying prescribed minimum Euclidian distance criteria among multiple ambiguity symbols in the subset of best symbol candidates; and generating a subset of best symbols including a prescribed number of symbols from the symbol constellation determined to be closest to the input sample. The subset of best symbols is used in a subsequent iteration of the steps of generating the subset of best symbol candidates and identifying at least one symbol satisfying the prescribed minimum Euclidian distance criteria.

Abstract: A method of detecting received data in a communication system includes the steps of: performing a QR decomposition on a received input vector as a function of one or more characteristics of a communication channel over which the input vector was transmitted; generating a subset of best symbol candidates from a symbol constellation by comparing an input sample (corresponding to an element of the input vector) with one or more prescribed thresholds; identifying at least one symbol satisfying prescribed minimum Euclidian distance criteria among multiple ambiguity symbols in the subset of best symbol candidates; and generating a subset of best symbols including a prescribed number of symbols from the symbol constellation determined to be closest to the input sample. The subset of best symbols is used in a subsequent iteration of the steps of generating the subset of best symbol candidates and identifying at least one symbol satisfying the prescribed minimum Euclidian distance criteria.

Abstract: An information handling system processes a sequence of instructions that includes first and second instructions. Each of the first and second instructions is processable in a sequence of stages that includes first and second execution stages. The first instruction's second execution stage is processable substantially concurrent with processing the second instruction's first execution stage. The first instruction is executed during its second execution stage. The second instruction is executed during a selected one of its first and second execution stages. A computer program product includes apparatus from which a computer program is accessible by an information handling system. The computer program is processable by the information handling system for causing the information handling system to assemble the sequence of instructions.

Abstract: A processor for performing a block floating point Fast Fourier Transform having improved signal to quantization noise ratio performance. In the radix-2 Decimation In Time algorithm, overflow between stages is prevented by a scale down by two invoked by comparison with a fixed comparison constant. Unfortunately, the fixed comparison constant is not always optimum for maximizing the signal to quantization noise ratio, which is degraded by excessive scale down. Moreover, current mechanisms are limited to the radix-2 block floating point FFT. The processor of the present invention provides the programmer with a FFT compare register which is loadable under program control, thus allowing the programmer to adjust the threshold at which scale down of the stage output is activated for better control over the signal to quantization noise ratio. In addition, the present invention supports other FFT structures besides the radix-2 block floating point FFT.