DFT-s-OFDM with Interleaved Subslot-Index Modulation: Waveform Design for ISAC

In this paper, a novel waveform is proposed for multiple-input multiple-output aided integrated sensing and communication (MIMO-ISAC) systems, namely discrete Fourier transform-spread OFDM with interleaved subslot-index modulation (DFT-s-OFDM-ISIM). To enhance both communication and sensing capabilities, we propose to integrate index modulation (IM), DFT-spread, and interleaving methodologies into the conventional OFDM waveform, thus leveraging their respective advantages. By adopting this communication-oriented waveform, we introduce a compressed sensing (CS) based estimation for radar sensing. Our simulation results reveal that the proposed scheme offers remarkable improvements over the conventional IM and DFT-s based schemes in terms of bit error rate (BER), while also exhibiting excellent radar sensing performance.