Frequency detection system

摘要

The disclosed frequency detection system samples a sinusoidal input V(t) with a predetermined constant sampling period h to form four sampled values V(to-2h), V(to-h), V(to+th) and V(to+2h) and calculates <IMAGE> where omega designates an angular frequency of the sinusoidal input after the conversion to corresponding digital values to provide a measure of its frequency. Further the absolute value of the frequency may be obtained by making an arc-cosine of one half the y(h).