Joint Transmit-receive Beam Design of FDA-MIMO Dual-function Radar-communication Systems for Radio-frequency Stealth

Abstract

Efficient Radio-Frequency (RF) stealth is crucial for Dual-Function Radar-Communication (DFRC) systems that detect radar stealth and con vert communication transmission. However, traditional beamforming schemes based on phased arrays and Multiple-Input Multiple-Output (MIMO) systems lack the ability to control the radiation energy in the range dimension, resulting in the facile interception of integrated transmission signals by enemy-owned passive detection systems. To address this issue, a joint transmit-receive beamforming design for Frequency Diversity Array MIMO (FDA-MIMO) DFRC systems is designed herein to achieve RF stealth. First, an integrated transmission signal model based on orthogonal waveform generation, frequency diversity modulation, and weighted transmission beamforming is constructed. The two-dimensional expression of the distance angle between the radar equivalent transmission beam pattern and the communication transmission channel is obtained through matched filtering and reception beamforming. Second, with communication information embedding and communication reachable rate as constraints, a joint optimization model for FDA-MIMO radar communication integrated transmission and reception beams for RF stealth is established. The model aims to simultaneously minimize the equivalent transmission beam power at the radar target and maximize the output signal-to-noise ratio. Finally, a joint optimization algorithm based on Weighted Mean-Square Error Minimization (WMMSE) and the Consensus Alternating Direction Method of Multiplier (C-ADMM) is proposed. Closed form expressions for each variable are derived and combined with convex optimization algorithms to achieve low-complexity solutions. The simulation results show that radar detection and communication transmission using the proposed method form a “point-to-point” pattern on the two-dimensional plane of range and angle, exhibiting good RF stealth capability. Simultaneously, this method can provide high clutter and interference suppression performance as well as a low communication bit error rate.

Keywords

• radio-frequency stealth
• dual-function radar-communication (dfrc)
• frequency diversity array (fda)
• multiple-input multiple-output (mimo)
• beamforming