Quantum Optical Integrated Sensing and Communication With Homodyne BPSK Detection

2026-01-11

IEEE Wireless Communications Letters

AI Summary

This work addresses the challenge of jointly optimizing communication and sensing in phase-insensitive Gaussian channels with unknown deterministic phase rotations. The authors propose an integrated quantum optical sensing and communication scheme based on BPSK modulation and homodyne detection. By jointly performing symbol detection and phase estimation—leveraging an expectation-maximization algorithm together with adaptive adjustment of the local oscillator phase—the framework achieves, for the first time in a quantum optical link, unified optimization of communication bit error rate and sensing accuracy quantified via Fisher information. This approach reveals the fundamental trade-off between these two performance metrics. Numerical experiments demonstrate that the proposed method enables controllable balancing of sensing precision while maintaining reliable communication performance.

Technology Category

• Search and Optimization: Learning to Search
• Computer Vision: Learning & Optimization for CV
• Constraint Satisfaction and Optimization: Constraint Optimization

Application Category

• Security and Privacy: Large-scale security measurements
• Semantics and Knowledge: Methods to enhance, augment, integrate or synergize semantic models such as knowledge graphs and LLMs
• Search and Retrieval-Augmented AI: Retrieval-Augmented Generation (RAG) and multi-modal RAG

Abstract

In this letter, we propose a quantum integrated sensing and communication scheme for a quantum optical link using binary phase-shift keying modulation and homodyne detection. The link operates over a phase-insensitive Gaussian channel with an unknown deterministic phase rotation, where the homodyne receiver jointly carries out symbol detection and phase estimation. We formulate a design problem that minimizes the bit-error rate subject to a Fisher information-based constraint on estimation accuracy. To solve it, we develop an iterative algorithm composed of an inner expectation-maximization loop for joint detection and estimation and an outer loop that adaptively retunes the local oscillator phase. Numerical results confirm the effectiveness of the proposed approach and demonstrate a fundamental trade-off between communication reliability and sensing accuracy.

Problem

• quantum sensing
• integrated communication
• phase estimation
• bit-error rate
• Fisher information

Innovation

• quantum integrated sensing and communication
• homodyne detection
• BPSK modulation
• Fisher information
• expectation-maximization algorithm