Communications device and related method with reduced false detects during start of message bit correlation

A method of processing a communications signal, comprising:

• receiving within a modem a repeated preamble bit or symbol pattern as a training sequence for a binary phase shift keyed (BPSK) communications signal;
• generating an initial frequency offset estimate and phase error estimate by processing a Fast Fourier Transform (FFT) that spans a block of samples for the BPSK communications signal and detects the repeated preamble pattern for the block of samples within the communications signal;
• and
• correlating for the Start of Message sequence and for different phases of the repeated preamble pattern to determine when a good Start of Message acquisition has occurred.

A communications device, comprising:

• a signal input for receiving a binary phase shift keyed (BPSK) communications signal having a repeated preamble bit or symbol pattern;
• a modem that processes the BPSK communications signal and further comprising a demodulator and processor that generates an initial frequency offset estimate and phase error estimate by detecting the repeated preamble pattern for a block of samples within the communications signal, correlates within a Start of Message correlator to search for the Start of Message sequence and correlates different phases of the repeated preamble pattern within training correlators for reducing false detections of the Start of Message;
• and
• radio circuitry operative with the modem for processing communications data obtained from the communications signal.