Design and Analysis of Low-Complexity Communication Receiver for PSK–LFM Joint Sensing and Communication Waveform

In this article, we propose novel strategies for preamble detection and synchronization to detect the symbols from the phase shift keying-linear frequency modulated (PSK-LFM) joint sensing and communication waveform at the communication receiver of an unmanned aerial vehicle (UAV). Since radar waveform requires huge bandwidth (order of 100 MHz–2 GHz) for better range resolution, processing the same waveform at the UAV's communication receiver necessitates high analog-to-digital converter (ADC) sampling rates. To reduce the ADC sampling requirements, in this paper, we propose two signal processing schemes for the communication receiver. In first, a part of the received signal is filtered using a low pass filter (LPF) and sampled for preamble detection, symbol synchronisation, and detecting the symbols. In the other case, the entire signal undergoes undersampling for subsequent processing. Furthermore, we obtain bit error rate (BER) performance for all the cases by considering time, phase, and carrier frequency offsets. We show that processing the undersampled signal yields superior BER performance compared to the filtering approach, even when both operate at an equivalent sampling rate. Furthermore, for all cases, we compare the simulation results with and without offsets, along with the analytical results obtained without offsets.