Method for Determining the Time Delay of Frequency-Shift Keyed Signals on the Basis of Modified Capon's Method of Minimum Variance

We propose a method for determining the time delay of frequency-shift keyed signals on the basis of the digital filtering algorithm insensitive to carrier-frequency shifts. The filter coefficients correspond to the information-optimal solution of the problem of variance minimization at the linear-filter output. Efficiency of the proposed method is shown under conditions of additive noise and inexact knowledge of the center frequency of the processed-signal spectrum. The developed algorithm permits simple realization for real-time operation on the basis of a digital signal processor. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 7, pp. 633–640, July 2008.