PRACTICAL ASPECTS OF A FAST ALGORITHM FOR FREQUENCY DETECTION

Previous works by the authors have advanced a novel frequency location technique based on recursive filtering concepts. The complexity is pr oportional to the signal length, which motivates the term, ''fast.'' A symptotic theory reported elsewhere does not give the full picture. Th e main objective is to discuss practical computational considerations, and through simulation, compare the performance of our algorithm with alternatives. The gist of our findings is that for tow signal-to-nois e power ratios, our method is supreme among the available fast detecto rs. There is a theoretical reason to anticipate this: We have extended earlier explorations by devising an enhancement which simultaneously narrows the bandwidth while the location recursion proceeds. The effec t is to vastly amplify the signal-to-noise ratio as the detector homes in on the target frequency. A practical procedure is offered which, e xperimentally, appears to be an effective guide in determining whether the detector output is meaningful or spurious (because the signal is too weak, or is nonexistent).