Fast ambiguity processing in SOFAR propagation involving periodic signals and M sequences

Fast ambiguity processing can be used in active time delay and Doppler identification in the sound fixing and ranging (SOFAR) propagation context. They need periodic signals generated from pseudo-random M sequences. In the particular case of the SOFAR, the range of the observed Doppler effect enables use of the fastest version, provided that the periodicity of the signal is correctly adjusted.