Detecting LFM Parameters in Joint Communications and Radar Frequency Bands

As a significant radar waveform, linear frequency modulation (LFM) is widely used in both military and civilian applications. Recently, there has been increasing interest in using the same radio spectrum to enable the radar and communication signals to coexist. This paper explores methods capable of estimating LFM parameters, particularly in the presence of co-channel orthogonal frequency division multiplexing (OFDM) signals. In particular, this paper applies the discrete chirp Fourier transform (DCFT) to this specific scenario and also compares this approach to the idea of reusing an OFDM receiver to estimate the LFM parameters. Through simulations, we demonstrate the use of the Hough transform to confirm that these can be identified to a high degree of accuracy. In addition, we discuss how this "reuse" approach opens up new applications for storing waveforms of interest for later data analysis.