Abstract: An automatic gain control (“AGC”) system. The system includes a first multiplier, an envelope detector, a summation module, a filter module, a convergence module, and a feedback module. The convergence module includes a convergence control module and a second multiplier. The feedback module includes an accumulator, a scalar multiplier module, and a third multiplier. The system is configured to adjust or modify its convergence speed according to the state of convergence of the AGC system, and the convergence speed of the AGC system is substantially independent of a signal level of the received signal.

Abstract: A method and system for determining a step size of an adaptive equalizer for a digital data receiver. The data received by the receiver includes coded symbols and uncoded symbols. The method includes determining a first error estimate based on decoded symbols corresponding to the coded symbols, determining a second error estimate based on the uncoded symbols, adaptively selecting the first error estimate or the second error estimate based on a convergence criterion, and determining a step size based on the selected error estimate.

Abstract: Embodiments of the invention relate to systems and methods for tracking phase in a receiver which uses multiple phase tracking techniques. A phase tracking module generates a plurality of symbol decisions related to received 8-level-vestigial-sideband (“8VSB”) signals, determines a phase tracking threshold value based on a mean square error, receives an estimated imaginary component of a transmitted signal based on the symbol decisions, and determines a phase estimate based on the imaginary component of the transmitted signal and the plurality of symbol decisions. The phase tracking module selects one of a first phase tracking technique and a second phase tracking technique based on the phase estimate. The first phase tracking technique is selected when the phase estimate is greater than the phase tracking threshold value, and the second phase tracking technique is selected when the phase estimate is less than the phase tracking threshold value.

Abstract: Systems and methods of carrier frequency acquisition or recovery in a receiver. The receiver is able to achieve carrier acquisition when a frequency offset is large (e.g., near a decision boundary). The receiver includes a demodulator, an equalizer, and a carrier recovery module. The carrier recovery module includes a decision device and phase detector, a phase error differentiator, a frequency direction confidence module, and a frequency and phase combiner module. The carrier recovery module calculates a phase error differential between a phase error at a first time and a phase error at a second time. Based on the phase error differential, the frequency direction confidence module generates a frequency offset confidence number. The frequency offset confidence number provides an indication of the direction of a frequency offset and a degree of certainty related to a detected direction (e.g., positive or negative) of the frequency offset.