Efficient Transmit Waveform Design for MIMO-OFDM DFRC Systems with 1-Bit DACS

2026-09-29

AI Summary

This study addresses the waveform design challenge for MIMO-OFDM dual-function radar-communication (DFRC) systems employing 1-bit DACs by proposing an efficient optimization framework that integrates constructive interference (CI) with integer programming. Specifically, the Fisher information matrix at target angles is maximized, and a time-frequency alternating ADMM algorithm preserving CI constraints is developed. By incorporating inexact updates and subcarrier-level decomposition strategies, this approach effectively overcomes the computational bottlenecks associated with discrete phase constraints. Simulation results demonstrate that the proposed method significantly improves algorithmic convergence and feasibility under extremely low hardware costs, simultaneously ensuring both radar detection accuracy and communication performance.

Abstract

This paper studies efficient waveform design for MIMO-OFDM dual-functional radar-communication (DFRC) systems with 1-bit digital-to-analog converters (DACs), which remains underexplored in the literature. We formulate the DFRC waveform design problem by maximizing the trace of the target angular Fisher information matrix (FIM), subject to symbol-error probability constraints realized via constructive interference (CI) and a time-domain 1-bit transmit alphabet constraint. The resulting problem is a large-scale nonlinear integer programming problem. We develop an inexact alternating direction method of multipliers (ADMM) algorithm with alternating time- and frequency-domain updates. The proposed scheme enables subcarrier-wise optimization in the frequency domain and closed-form primal and dual updates in the time domain. In particular, the CI constraints are deliberately retained in both the time- and frequency-domain subproblems to promote the feasibility of intermediate iterates and improve the convergence behavior of ADMM. Simulation results demonstrate promising DFRC performance.

Problem

• MIMO-OFDM
• DFRC
• Waveform Design
• 1-Bit DACs
• Nonlinear Integer Programming

Innovation

• MIMO-OFDM DFRC
• 1-bit DACs
• Waveform Design
• Constructive Interference
• Inexact ADMM