Abstract: An apparatus includes a global synchronization interface and multiple modules. The global synchronization interface includes a global synchronization driver for driving a global synchronization signal. The modules include corresponding local synchronization interfaces, each local synchronization interface having a local synchronization driver for driving a local synchronization signal. In a local mode, the modules ignore the global synchronization signal and synchronize corresponding operations according to the local synchronization signal and a global reference signal. In a global mode, the modules ignore the local synchronization signal and synchronize the corresponding operations according to the global synchronization signal and the global reference signal.

Abstract: One embodiment of the invention includes a system comprising an analog baseband signal input, a conversion circuit with N Analog to Digital Converters (ADCs) operable to receive the analog baseband signal, and a Finite Impulse Response (FIR) filter operable to receive outputs of the N ADCs and to produce a digital representation of the analog baseband signal corrected for a mismatch in the N ADCs.

Abstract: In one representative embodiment, multiple ensembles of samples of a periodic or cylcostationary signal are processed in a time aligned manner. The sampling rate of the processing system is adjusted so that an integer number of sampling intervals equals the period of the signal. A cyclic counter is programmed to reset according to the integer number. Also, the cyclic counter may be initialized according to an external trigger. During operation, the cyclic counter is incremented when each sample is received. Continuous operation of the cyclic counter with the capturing of samples enables precise time alignment between ensembles of samples. Specifically, the beginning of a discrete ensemble is identified by a reset of the cyclic counter. Because each ensemble is time aligned, further processing (e.g., coherent averaging) may occur without post-processing to time-shift each sample to achieve the time alignment.

Abstract: In one representative embodiment, multiple ensembles of samples of a periodic or cylcostationary signal are processed in a time aligned manner. The sampling rate of the processing system is adjusted so that an integer number of sampling intervals equals the period of the signal. A cyclic counter is programmed to reset according to the integer number. Also, the cyclic counter may be initialized according to an external trigger. During operation, the cyclic counter is incremented when each sample is received. Continuous operation of the cyclic counter with the capturing of samples enables precise time alignment between ensembles of samples. Specifically, the beginning of a discrete ensemble is identified by a reset of the cyclic counter. Because each ensemble is time aligned, further processing (e.g., coherent averaging) may occur without post-processing to time-shift each sample to achieve the time alignment.

Abstract: Data values representing the (I2+Q2) values are converted to floating-point representations and a histogram of the floating-point numbers is generated. The count for each histogram bin in the histogram is stored in a memory. Each floating-point number acts as an address for a corresponding histogram bin in the memory. The accumulated counts in the histogram bins are then grouped into a desired number of CCDF bins, and the CCDF curve is derived from the histogram data. Grouping the histogram bins into the CCDF bins may include combining one or more histogram bins into a single CCDF bin. Linear interpolation is used to divide a count value in a histogram bin between two CCDF bins when the histogram bin does not align with a single CCDF bin.

Abstract: Pipelined digital accumulators. Parallel digital accumulators for use in digital signal processing are improved through pipelining. An accumulator is partitioned into a plurality of pipelined stages, and the pipeline delay is used to reduce the effect of carry propagation through the accumulator. While input and output delay registers are used in the accumulator partitions, the output delay registers are not needed if the results of those partitions are not needed in subsequent stages of computation. If phase coherence is not needed, input delay registers may not be needed on accumulator partitions. In the limiting case of one bit per partition, the effective speed of the pipelined accumulator is equivalent to the speed of a single bit accumulator stage.