Sidelobe Level Reduction in Pulse Compression With Classical Orthogonal Polynomials and Woo Filter

Abstract

The present dissertation aims to make an in-depth study on the Radar pulse compression. Pulse compression is used in the radar systems to avail the benefits for large range detection and high range resolution capability by long and short duration pulses respectively. Usually, matched filter (MF) and auto-correlation function (ACF) are used to analyse the pulse compression output. The output of the pulse compression of a modulated signal is associated with range side-lobes along with the main-lobe. These side-lobes are undesirable because they may contain the information associated to the target which is nearer to a stronger or desired target due to this the performance of the radar detection system is affected. In this dissertation, to improve the performance of radar system, few investigations have been made to reduce the side-lobes in the pulse compression output. Firstly, a fundamental comparative analysis on time-bandwidth product of a short duration exponential signal is analysed. The amplitude variation has been varied with an exponent as an integer and non-integer are observed. In order to improve time-bandwidth product in the pulse compression, different Classical Orthogonal polynomials of different orders are analysed. Then Chebyshev polynomials are used to generate the sequence which has low sidelobe levels in the output of the compressed signal. In this dissertation using P4 code of length 1000, merit factors such as peak sidelobe level, integrated sidelobe level and relative mainlobe width are calculated for the proposed model. The results are compared with other techniques that use the Woo filter concepts.