Performance evaluation of time compression overlap-add radar systems based on order-statistics CFAR under convolution noise jamming

Abstract

We introduce a new scheme that integrates the Time Compression OverLap-Add (TC-OLA) spread spectrum technique into radar systems, more specifically the Linear Frequency Modulation Pulse Compression (LFM-PC) radar. This technique increases the signal to noise ratio (SNR) and, as a consequence, enables a greater processing gain compared to the traditional radar LFM-PC systems. In addition, TC-OLA allows the radar designer to control the spreading of the signal and therefore provides a better immunity against powerful jamming techniques. In our simulation, we extend the conventional LFM-PC radar model by appropriately adding Time Compression (TC) and Overlap-add (OLA) blocks at the transmitter and receiver, respectively. The evaluation performance of the proposed system and the convention LFM are done under AWGN and under one of the smart jamming technique called Convolution Noise Jamming (CNJ) using different Constant False Alarm Rate (CFAR) algorithms, namely, Cell-Average (CA), Greatest-Of (GO), and Order-Statistics (OS) CFAR. Using the TC-OLA-based LFM radar system, we show that we have higher SNRs while preserving the same Doppler shift and target time delay as the conventional LFM radar system. Furthermore, the proposed radar model relies on high sample rates only after the conventional LFM radar transmitter blocks and before conventional LFM radar receiver blocks. Therefore, it does not require changing any parameters of the conventional radar blocks.