Learning-Based Beam Adaptation for Active/Passive-Aware Monopulse ISAC with Leakage Suppression

Jafar Norolahi; Alireza Vahid

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arXiv · 2610.03600

Learning-Based Beam Adaptation for Active/Passive-Aware Monopulse ISAC with Leakage Suppression

Jafar Norolahi·Alireza Vahid

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Abstract

This paper proposes a learning-based beam adaptation framework for active/passive-aware monopulse integrated sensing and communication (ISAC) with spatial leakage suppression. A single gNB uses a shared array and orthogonal frequency division multiplexing dual-functional radar-communication signaling to jointly support downlink transmission and monopulse sensing. Radar detections and uplink spatial evidence are fused to distinguish cooperative active directions from passive directions, while a protected angular zone limits unintended illumination. Soft Actor-Critic deep reinforcement learning adapts the transmit beam using communication, sensing, leakage, and previous-action feedback. Numerical results show accurate active/passive spatial classification and robust leakage control as the number of passive targets increases from one to twelve. The proposed SAC controller maintains aggregate passive leakage below the prescribed budget across the full sweep and, from two passive targets onward, achieves the highest leakage-compliant sum rate among the considered baselines.

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BibTeX RIS

Jafar Norolahi, Alireza Vahid. 2026-10-02. Learning-Based Beam Adaptation for Active/Passive-Aware Monopulse ISAC with Leakage Suppression. https://arxiv.org/abs/2610.03600

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