Robust detection in ultra-wideband impulse radar using DPSS-MMSE estimator

In this paper, it has been shown that non-stationary received signals at ultra-wideband impulse radars can be addressed by Fourier series model with time-varying coefficients. Next, simply by computing statistical features of the coefficients, we show that this model can be considered as a sum of band-limited sources. Based on the unconditional orthonormal representation of band-limited signals, a MMSE estimator is introduced to determine the Fourier coefficients. Getting the most out of our novel estimator, we suggest a new method for blind and robust detection that enables us to determine the range and velocity of moving targets, accurately without utilizing any matched filters. In this new approach, no prior information is required for detection, except pulse repetition interval. Since the novel method is based on the non-stationary analysis, the signal is analyzed in a long period of time to estimate the velocity in high resolution. Furthermore, since there is no assumption on the noise distribution, the signal of interest can be simply detected in the presence of correlated and non-Gaussian noise, i.e., encompassing the conglomerate effects of clutter and interference. To verify our result, an experimental test and simulations are also presented comparing the new detector with conventional ultra-wideband impulse radar detectors referred to as interleaved periodic correlation processing (IPCP) in the literature.