Estimation of range-Doppler radar images

It is shown that most accurate reconstruction of a range-Doppler target density that can be computed from N waveforms and their echoes is obtained by transmitting the singular functions corresponding to the N largest singular values of two kernels derived from the target density. The singular functions are valid wavelets that obey an additional orthogonality constraint in the frequency domain. Using this result, a solution is discussed for the problem of choosing a set of N waveforms to reconstruct with high accuracy an arbitrary unknown target range-Doppler density function