Transmitter-in-the-loop optimization of distorted OFDM radar emissions

The inherent amplitude modulation of orthogonal frequency division multiplexing (OFDM) has limited its use in radar due to transmitter-induced distortion. Specifically, there is a necessary trade-off between reduced SNR caused by power back-off to accommodate these AM effects and the waveform distortion that occurs when driving the amplifier closer to saturation. Here a method is developed to design OFDM-based radar emissions with low range sidelobes in the presence of transmitter-induced distortion. This work builds upon previous results for hardware-in-the-loop optimization of continuous phase modulation (CPM) waveforms to demonstrate how saturated OFDM emissions may potentially provide a feasible alternative waveform design scheme.