Low symbol rate rapid carrier acquisition with extremely large frequency offset for digital communication receiver

A system for rapid non-data aided carrier signal acquisition for a low symbol rate carrier signal, the system comprising:

• a receiver configured to receive an analog intermediate frequency carrier signal;
• an analog-to-digital converter configured to convert the analog intermediate frequency carrier signal received by the receiver to a digital carrier signal;
• a digital quadrature tuner configured to down-convert the digital carrier signal to a frequency substantially at baseband;
• a decimation filter configured to reduce a sampling rate of the digital carrier signal substantially at baseband using a decimation filter;
• an FFT module configured to generate a result of one or more FFT's and determine a highest Fast Fourier Transform (FFT) based on the result using a peak finder;
• a multiplexer configured to select an input source for the FFT module;
• a walking coarse detector (WCD) configured to generate a frequency estimate of the digital carrier signal;
• and
• a carrier recovery loop (CRL) configured to be tuned based on the frequency estimate generated by the walking coarse detector (WCD), the CRL further comprising an oscillator configured to achieve carrier signal lock by being programmed to a final carrier frequency offset estimate that is determined by a processor using a result of the FFT module, a modulation removal, and the peak finder;
• and
• wherein the walking coarse detector (WCD) is further configured to correlate a received modulated carrier signal with a delayed version of the received modulated carrier signal and calculate a first frequency estimate of the digital carrier signal using an arctangent function and a multiplier of 4Rs/(2π) where Rs equals a symbol rate of the digital carrier signal.