volume | PIER Journals

Abstract

It is well known that using proper signal compression techniques, the range resolution of the radar systems can be enhanced without having to increase the peak transmits power. Whereby the range resolution is inverse proportional with the frequency band of the scanning signals, in the last period of time, in radar systems literature a lot of suitable wideband signals were designed and analyzed as performance level. However, for the large majority of these signals, the compression filter response contains significant sidelobes which may cause difficulties in the target detection and range estimation process. Consequently, in the radar signal processing theory, the sidelobes reduction techniques using synthesis of some proper nonlinear FM (NLFM) laws represents a major scientific research direction. In order to assure the sidelobes suppression, the main objective of this paper is to present an adequate synthesis algorithm of some NLFM laws based on stationary phase principle. The achieved experimental results confirm a significant sidelobes reduction (i.e., more than -40 dB) without necessity to apply some weighting techniques. Finally, the analysis of the synthesized NLFM laws by ambiguity function tool was also discussed.

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Prof. Iulian Constantin Vizitiu