Rydberg Atomic Quantum Receivers for Classical Wireless Communications and Sensing: Their Models and Performance

TL;DR

This paper develops an end-to-end signal model for Rydberg Atomic Quantum Receivers (RAQRs) and analyzes their performance in aiding classical wireless communications and sensing. It introduces a four-level quantum transition model with a steady-state density-matrix solution and an RF-to-optical transformation via EIT, yielding a realistic transfer function from input RF to output optical signals. An end-to-end RAQR-aided receiver is detailed, including two photodetection schemes (DIOD and BCOD), down-conversion, and a narrowband equivalent baseband model for both communications and sensing. Noise sources—BBR-induced dephasing, quantum projection noise, photon shot noise, and intrinsic thermal noise—are quantified and integrated into SNR analyses under SQL and PSL regimes, with BCOD shown to outperform DIOD and offer significant gains over classical RF receivers. Simulation results validate the model, demonstrate substantial SNR gains (over $27$ dB PSL and $40$ dB SQL), and highlight the impact of practical impairments and parameter optimization, pointing to a promising yet challenging path toward RAQR-aided wideband and MIMO wireless systems.

Abstract

The significant progress of quantum sensing technologies offer numerous radical solutions for measuring a multitude of physical quantities at an unprecedented precision. Among them, Rydberg atomic quantum receivers (RAQRs) emerge as an eminent solution for detecting the electric field of radio frequency (RF) signals, exhibiting great potential in assisting classical wireless communications and sensing. So far, most experimental studies have aimed for the proof of physical concepts to reveal its promise, while the practical signal model of RAQR-aided wireless communications and sensing remained under-explored. Furthermore, the performance of RAQR-based wireless receivers and their advantages over classical RF receivers have not been fully characterized. To fill these gaps, we introduce the RAQR to the wireless community by presenting an end-to-end reception scheme. We then develop a corresponding equivalent baseband signal model relying on a realistic reception flow. Our scheme and model provide explicit design guidance to RAQR-aided wireless systems. We next study the performance of RAQR-aided wireless systems based on our model, and compare them to classical RF receivers. The results show that Doppler broadening-free RAQRs are capable of achieving a substantial received signal-to-noise ratio (SNR) gain of over $27$ decibel (dB) and $40$ dB in the photon shot limit and standard quantum limit regimes, respectively.

Figures (9)

• Figure 1: (a) The superheterodyne structure of RAQRs, and (b) its corresponding four-level scheme.
• Figure 2: Illustration of the RAQR-aided wireless receiver.
• Figure 3: Illustration of main noise sources: (a) RAQRs and (b) classical RF receivers.
• Figure 4: (a) Waveform, (b) normalized approximation error, and (c) input-output transfer function characterized by our models.
• Figure 5: Optimization of parameters: (a) LO signal amplitude $U_y$, and (b) probe beam power $\mathcal{P}_{0}$, (c) probe beam detuning $\Delta_{p}$, (d) coupling beam detuning $\Delta_{c}$, and (e) LO detuning $\Delta_{l}$. (f) Compare the joint optimization of $\Delta_{p,c,l}$ to their independent optimizations and to the case without detuning optimization of $\Delta_{p,c,l} = 0$.