Waveform Shaping in Integrated Sensing and Communications

The major challenge to integrated sensing and communications (ISAC), as a prospective signaling technique in 6G wireless networks, is how to integrate both functions in the same waveform. In this paper, within the framework of orthogonal frequency division multiplexing (OFDM), it is proposed to carry out communication modulation in the phase while shaping the waveform for sensing by masking the frequency spectrum using a dedicated window function. The rationale behind this scheme is the near-optimality of quadratic phase shift keying (QPSK) and the Fourier duality between the power spectral density (PSD) and the time autocorrelation function. The proposed scheme is demonstrated using numerical simulations and USRP X410 based experiments.