Waveform and Processing Algorithm Design for Frequency-Hopping MIMO Radar-Communication Integration Utilizing Multi-Parameter Modulation

Dual-functional radar-communication (DFRC) systems have gained attention for their advantages in spectrum sharing and hardware integration. Frequency-hopping (FH) MIMO radar waveforms enable communication via index modulation but introduce challenges such as increased range sidelobes, suboptimal communication performance, and incompatibility with conventional MIMO detection. Based on these considerations, we propose a new DFRC waveform design that combines frequency-hopping code selection (FHCS), binary frequency-shift keying (BFSK), and permutation selection (PS), termed FHCS-BFSK-PS. This design utilizes FH code vectors, frequency codes, and carrier-to-antenna mapping matrices as modulation parameters, embedding communication information across three dimensions: FH code index, frequency, and spatial phase. For communications, leveraging the weak coupling among these parameters, a simple and efficient demodulation algorithm based on the matched filtering criterion is proposed. For radar detection, we analyze the impact of fast-time domain FH on conventional MIMO detection and propose a modified detection method. This approach calculates and sums the log-likelihood ratios across multiple subpulses, thereby avoiding the incoherent accumulation of steering vectors in the subpulse domain. Finally, simulation results demonstrate the feasibility of the proposed scheme in target detection and highlight its superior performance in terms of symbol error rate (SER), data rate, and ambiguity function characteristics.