Optimal Mismatched Filter Design by Combining Convex Optimization With Circular Algorithm

Abstract

Mismatched filters (MMF) have been intensively explored for linear-frequency modulation (LFM) waveform sidelobe reduction. Unlike other design strategies, the use of convex optimization (CO) techniques is able to find the optimal design. However, existing studies for CO-based MMF design have focused on minimizing peak sidelobe level (PSL), which might not take the mainlobe widening sacrifice into account. To address this issue, this paper proposes a weighted CO model targeting a flexible tradeoff between sidelobe suppression and mainlobe widening. Moreover, to better control the optimization problem via the presented CO model, the cyclic algorithm (CA) is employed to determine upper limits on mainlobe width. Consequently, the proposed tradeoff MMF design by combining CA with CO would be feasible to meet the requirements of different target detection scenarios. Comprehensive simulations have been carried out to demonstrate the effectiveness of our presented MMF design.INDEX TERMS Mismatched filter, convex optimization, cyclic algorithm, sidelobe suppression.

Enhanced range-doppler algorithm for SAR image formation

“…Adopting a mismatched filter might further reduce PSL at the price of loss-in-processing gain (LPG) [7], even if, a matched filter is necessary for the receiver in the presence of additive white gaussian noise [8]. This LPG may be described as the difference between the ideal SNR at the output of the mismatched filter SNR mismatched and the SNR of the matched filter SNR matched .…”

“…Therefore, from the perspective of optimization, it makes sense to construct a mismatched filter. One of the most powerful tools to solve this problem is Quadratic Constrained Quadratic Program (QCQP) [7]. QCQP is a convex optimization technique, including interior point methods, that resolves the PSLR problem [8].…”

An Identification Method of Corner Reflector Array Based on Mismatched Filter through Changing the Frequency Modulation Slope

“…Nevertheless, in comparison to the sophisticated waveforms proposed in recent years [27,28], it is relatively ineffective in mitigating interference and spoofing in radar detection. It is of great value to optimize the signal processing in order to enhance the radar performance [29]. In some previous studies, this technology was nearly applied at the transmitter by modifying the frequency modulation slope of the transmitting LFM signal to enhance the complexity of the waveform.…”