Design of Integrated Sensing and Communication Waveform for Distributed MIMO Radar

The data observed by each receiver of the distributed multiple-input-multiple-output (MIMO) radar need to be transmitted and gathered together for fusion processing to effectively utilize spatial diversity. Embedding the observation data into MIMO radar waveforms is an efficient way to address the observation data transmission requirement of distributed MIMO radar while maintaining the sensing performance to the maximum extent under the constraint of not increasing spectrum occupation. In this article, a data embedding mechanism based on the differences in correlation characteristics between transmission phase-coded signals is proposed. By establishing a mutual mapping relationship between data symbols and transmission waveforms, different antennas can transmit data symbols independently, relieving the constraint of antennas' spatial arrangement on data embedding. We propose the corresponding optimization criteria and optimization problems based on the working principle of integrated waveforms. The generation algorithms for both continuous phase-coded and discrete phase-coded signals are introduced. In the case of embedding 1-bit data into each pulse, we propose an efficient waveform set design method that ensures optimal communication performance of the proposed integrated waveform by reasonably simplifying the original waveform problem. Furthermore, symbol decision criteria and theoretical symbol error rate under the minimum distance criterion are derived. Numerical results validate the derived symbol error rate and reveal the tradeoff between the communication performance and sensing performance of the integrated waveform.