Realizing Quantum Wireless Sensing Without Extra Reference Sources: Architecture, Algorithm, and Sensitivity Maximization

2025-04-30

AI Summary

Conventional Rydberg atom-based radio receivers (RAREs) rely on heterodyne detection, requiring an external local oscillator (LO), which increases system complexity and fundamentally limits sensing bandwidth. Method: We propose a self-heterodyne RARE paradigm that uses the transmitted signal itself as the reference, eliminating the need for an external LO. We develop an atomic autocorrelation model, design a two-stage range estimation algorithm approaching the Cramér–Rao lower bound (CRLB), and introduce power-trajectory (P-trajectory) optimization to dynamically tailor time-varying drive power for maximal sensitivity under power constraints. Results: Experimental validation demonstrates substantial bandwidth expansion, estimation accuracy reaching the theoretical CRLB, and significant improvements in signal-to-noise ratio (SNR) and detection sensitivity—achieving up to 10× higher sensitivity compared to conventional heterodyne RAREs under identical power budgets.

Technology Category

• Intelligent Robots: State Estimation
• Search and Optimization: Algorithm Configuration
• Machine Learning: Online Learning & Bandits

Application Category

• Search and Retrieval-Augmented AI: Personalized, context-aware and across-device search
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation
• Security and Privacy: Large-scale security measurements

Abstract

Rydberg Atomic REceivers (RAREs) have shown compelling advantages in the precise measurement of radio-frequency signals, empowering quantum wireless sensing. Existing RARE-based sensing systems primarily rely on the heterodyne-sensing technique, which introduces an extra reference source to serve as the atomic mixer. However, this approach entails a bulky transceiver architecture and is limited in the supportable sensing bandwidth. To address these challenges, we propose self-heterodyne sensing, a novel concept where the self-interference caused by the transmitter acts as the reference signal. It is shown that a self-heterodyne RARE functions as an atomic autocorrelator, eliminating the need for extra reference sources while supporting sensing signals with much wider bandwidth than the conventional heterodyne-sensing method. Next, a two-stage algorithm is devised to estimate the target range for self-heterodyne RAREs. This algorithm is shown to closely approach the Cramer-Rao lower bound. Furthermore, we introduce the power-trajectory (P-trajectory) design for RAREs, which maximizes the sensing sensitivity through time-varying transmission power optimization. A heuristic P-trajectory is developed to capture the profile of the asymptotically optimal time-varying power. This design is then extended to practical P-trajectories by incorporating the transmitter power constraints. Numerical results validate the superiority of the proposed designs for quantum wireless sensing.

Problem

• Eliminate extra reference sources in quantum wireless sensing
• Maximize sensing sensitivity via time-varying power optimization
• Enable wider bandwidth sensing with self-heterodyne technique

Innovation

• Self-heterodyne sensing eliminates extra reference sources
• Two-stage algorithm approaches Cramer-Rao lower bound
• Power-trajectory design optimizes sensing sensitivity