Optimum signal format for pulse compression radar

The design of a pulse compression radar is discussed in terms of a receiver with normalized output defined by an ambiguity function. An optimum narrowing of the ambiguity function along the time axis yields enhanced range accuracy and resolution. Optimal autocorrelation functions having the shortest duration for the allowable sidelobe level are found using Dolph-Chebyshev polynomials, leading to optimum sidelobe levels which are related to the beamwidth. The choice of a rectangular signal envelope and determination of the corresponding frequency law, in addition to the choice of a linear FM law and the determination of the signal envelope are considered. It is concluded that since the ambiguity function lacks a phase structure and the quasi-optimal autocorrelation function yields realizable signals, a Gaussian envelope with linear FM is the optimum signal for pulse compression radar.