Hypothesis Testing on FMCW and OFDM for Joint Communication and Radar in IEEE 802.11bd
Shahab Ehsanfar, Ahmad Bazzi, Klaus Mößner, Marwa Chafii
Abstract
In this paper, we provide a theoretical study on the receiver operating characteristic (ROC) of frequency-modulated continuous-wave (FMCW)-based radars, orthogonal frequency division multiplexing (OFDM)-based radars and the superposition of FMCW waveform and OFDM symbols in form of IEEE 802.11bd frame structure. Considering a 2-dimensional discrete Fourier transform for the estimation of range and velocity within the delay-Doppler domain, we derive the binary hypothesis tests for individual detection of real and imaginary components as well as their superposition in form of complex signal power. Evaluating the probability of detection and probability of false-alarm, we provide a performance comparison when the detection is solely based on FMCW preamble, random OFDM symbols, and their hybrid form. Via extensive simulation results, we show the feasibility of joint communication and radar within the currently existing IEEE 802.11bd technology. Our theoretically calculated detection probabilities suggest 5–7 dB performance gain of hybrid radar with respect to the individual FMCW and OFDM radars.