Interleaved Transceiver Design for a Continuous-Transmission MIMO OFDM ISAC System

This paper proposes an interleaved transceiver design method for a multiple-input multiple-output (MIMO) integrated sensing and communication (ISAC) system utilizing orthogonal frequency division multiplexing (OFDM). We consider a continuous transmission system and focus on transceiver design for alternate symbols to mitigate the interference to the radar from reflections of adjacent OFDM symbols. Constructive interference (CI) is incorporated into the optimization to improve communication performance, while the integrated mainlobe-tosidelobe ratio (IMSR) of the transmission beampattern ensures directivity. A time-domain radar receive filter is designed to reduce the range sidelobes and retain loss-in-processing gain, while also mitigating the interference to the radar and eliminating spurious peaks induced by distant targets. Given the high peak-to-average power ratio (PAPR) in OFDM systems, we constrain the power of each transmitted sample. The optimization problem is addressed using alternating optimization (AO), with the subproblem of transmitted waveform design being solved via successive convex approximation (SCA). Numerical simulations validate the effectiveness of our transceiver design in achieving desirable performance in both radar sensing and communication.