Creating sidelobe-free range zone around detected radar target

Abstract

To achieve good range response pulse radars transmit modulated or coded waveforms with good aperiodic autocorrelation function (ACF) and use a matched filter (MF) receiver. Range sidelobe (SL) can be considerably lowered by using a mismatched-filter (MMF), designed to minimize the integrated or peak SL. Low SL prevent masking weak neighboring targets and reduce the contribution from surrounding clutter. This paper suggests a different approach to SL reduction. It is based on designing a Modified MMF (MMMF) in which the near SL of the cross-correlation function (CCF) are given higher weight in the minimization process and are therefore more drastically reduced. A combination of the MMMF and a standard MF can create a SL-free response.

Non‐coherent pulse compression — aperiodic and periodic waveforms

“…An approach that is free of the Manchester encoding drawbacks is to transmit the unipolar version of S 1 , namely, S 3 = ( S 1 + 1)/2 Following non‐coherent envelope detection, the receiver cross‐correlates the detected envelope with an MMF to S 3 , designed to minimise the integrated cross‐correlation sidelobes. A twist to the design is to give more weight to the near sidelobes, as shown in [5]. If the extent of the zone defined as near sidelobes is about half the length of the entire sidelobes span, then there is only negligible increase in the height of the remaining sidelobes.…”