Abstract Continuously tunable Rydberg atomic receivers (CT-RARs) based on the AC Stark effect overcome the discrete-frequency limitations of resonant RARs, enabling wideband continuous spectrum coverage. However, existing studies lack a dynamic system model tailored to the CT-RAR, and nonlinear distortion characteristics remain poorly understood, which hinders further optimization of receiver sensitivity. This paper presents theoretical system modeling and performance analysis of the CT-RAR. A small-signal linearized dynamic model is established using time-dependent perturbation theory. We derive closed-form expressions for the dynamic frequency response and prove that the slope of the static response curve is strictly equivalent to the dynamic zero-intermediate-frequency gain. Further, the nonlinear distortion characteristics of the CT-RAR are analyzed using Floquet theory, and the total harmonic distortion under varying signal strengths is evaluated. Finally, we perform a parameter-dependence analysis. The CT-RAR exhibits inherent frequency-selection capability across a wide frequency range. This paper offers a theoretical foundation for guiding the practical design of CT-RARs.
Abstract Continuously tunable Rydberg atomic receivers (CT-RARs) based on the AC Stark effect overcome the discrete-frequency limitations of resonant RARs, enabling wideband continuous spectrum coverage. However, existing studies lack a dynamic system model tailored to the CT-RAR, and nonlinear distortion characteristics remain poorly understood, which hinders further optimization of receiver sensitivity. This paper presents theoretical system modeling and performance analysis of the CT-RAR. A small-signal linearized dynamic model is established using time-dependent perturbation theory. We derive closed-form expressions for the dynamic frequency response and prove that the slope of the static response curve is strictly equivalent to the dynamic zero-intermediate-frequency gain. Further, the nonlinear distortion characteristics of the CT-RAR are analyzed using Floquet theory, and the total harmonic distortion under varying signal strengths is evaluated. Finally, we perform a parameter-dependence analysis. The CT-RAR exhibits inherent frequency-selection capability across a wide frequency range. This paper offers a theoretical foundation for guiding the practical design of CT-RARs.
In recent years, electric field measurement techniques based on Rydberg atoms have shown unique advantages in high sensitivity and wideband applications and miniaturization. The Rydberg atom receiver senses the electromagnetic signal using the quantum coherence effect, which overcomes the inherent defects of traditional electronic receivers in terms of thermal noise, insertion loss of microwave devices, and the use of wavelength-dependent antennas, thus providing the Rydberg atomic receivers the potential to become the next generation of microwave receivers. For some particular application scenarios such as radar and communication, superheterodyne reception is a critical technical approach, and the linear dynamic range is an essential factor in evaluating the performance of the superheterodyne receivers. It is challenging to promote the Rydberg atomic receiver without figuring out the influence of system parameters on the linear dynamic range. This paper starts with the response mechanism of the Rydberg atomic superheterodyne receiver, and a theoretical model is established to simulate the atom-microwave responses. Then the harmonics' generation mechanism is discussed, and the atomic linear dynamic range under different probe light Rabi frequencies is studied further. Furthermore, a method to evaluate the antiblocking performance of the system is proposed. This work is expected to provide theoretical guidance for the design and performance optimization of the Rydberg atomic superheterodyne receiver.
Abstract The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches between the parameters of the received amplitude modulation (AM) signals and the system’s linear workspace and demodulation operating points can cause severe distortion in the demodulated signals. To address this, the article proposes a method for determining the operational parameters based on the mean square error (MSE) and total harmonic distortion (THD) assessments and presents strategies for optimizing the system’s operational parameters focusing on linear response characteristics (LRC) and linear dynamic range (LDR). Specifically, we employ a method that minimizes the MSE to define the system’s linear workspace, thereby ensuring the system has a good LRC while maximizing the LDR. To ensure that the signal always operates within the linear workspace, an appropriate carrier amplitude is set as the demodulation operating point. By calculating the THD at different operating points, the LRC performance within different regions of the linear workspace is evaluated, and corresponding optimization strategies based on the range of signal strengths are proposed. Moreover, to more accurately restore the baseband signal, we establish a mapping relationship between the carrier Rabi frequency and the transmitted power of the probe light, and optimize the slope of the linear demodulation function to reduce the MSE to less than 0.8 × 10 −4 . Finally, based on these methods for determining the operational parameters, we explore the effects of different laser Rabi frequencies on the system performance, and provide optimization recommendations. This research provides robust support for the design of high-performance Rydberg atom-based AM receivers.
Rydberg atomic quantum receivers represent a transformative approach to achieving high-sensitivity, broadband, and miniaturized radio frequency (RF) reception. However, existing static signal models for Rydberg atomic receivers rely on the steady-state assumption of atomic quantum states, which cannot fully describe the signal reception process of dynamic signals. To fill in this gap, in this paper, we present a transfer function-based model to compute the dynamic signal response of Rydberg atomic receivers in closed form. Specifically, by applying small-signal perturbation techniques to the quantum master equation, we derive closed-form Laplace domain transfer functions that characterize the receiver’s dynamic responses to time-varying signal fields. To gain more insights into the quantum-based RF-photocurrent conversion process, we further introduce the concept of quantum transconductance that describes the quantum system as an equivalent classical system. Simulations for Rydberg atomic receivers validate the proposed signal model, and demonstrate the possibility of quantum receivers to outperform classical electronic receivers through the improvement of quantum transconductance.
Rydberg atomic receivers represent a transformative approach to achieving high-sensitivity, broadband, and miniaturized radio frequency (RF) reception. However, existing static signal models for Rydberg atomic receivers rely on the steady-state assumption of atomic quantum states, which cannot fully describe the signal reception process of dynamic signals. To fill in this gap, in this paper, we present a general model to compute the dynamic signal response of Rydberg atomic receivers in closed form. Specifically, by applying small-signal perturbation techniques to the quantum master equation, we derive closed-form Laplace domain transfer functions that characterize the receiver’s dynamic responses to time-varying signal fields. To gain more insights into the quantum-based RF-photocurrent conversion process, we further introduce the concept of quantum transconductance that describes the quantum system as an equivalent classical system. By applying quantum transconductance, we quantify the influence of in-band blackbody radiation (BBR) noise on the atomic receiver sensitivity. Extensive simulations for Rydberg atomic receivers validate the proposed signal model, and demonstrate the possibility of quantum receivers to outperform classical electronic receivers through the improvement of quantum transconductance.
Rydberg atomic receivers (RARs) have emerged as a promising candidate for next-generation wireless communication systems due to their broadband tunability, SI traceability, compact configuration, and omnidirectional reception. Currently, the primary challenge hindering the further large-scale deployment of RARs lies in the low data transmission rates, which is attributed to the narrow instantaneous bandwidth. This work improves data transmission rates from a signal processing perspective, proposing a cost-effective and operationally efficient solution. The Rydberg-atom-based electro-optic conversion (RAEOC) system behaves as a linear system under strong local oscillator biasing and small-signal excitation. Specifically, we develop a dynamic response model for the RAEOC system and derive its frequency-response expression via time-dependent perturbation theory, Laplace transformation, and vectorization-based computation. Furthermore, we establish a comprehensive RAR communication simulation framework. Monte Carlo simulations demonstrate that the frequency-domain estimation and equalization algorithm can significantly improve the bit error rate performance of RARs in broadband signal reception. Our equalization method suppresses inherent passband distortion in RAR systems to enhance data throughput under finite bandwidth.
Rydberg atomic receivers (RARs) leverage the quantum coherence of highly excited atoms to overcome the intrinsic physical limitations of conventional radio frequency receivers (RFRs), particularly in sensitivity, and bandwidth. This innovative technology represents a paradigm shift in wireless communication systems. This paper systematically explains the fundamental sensing mechanisms of RARs, contrasts their differences from RFRs in working principles and architectures. We explore their advantages in emerging wireless communication scenarios, such as integrated sensing and communications, quantum Rydberg radar, and quantum space communications. Practical challenges, such as limited instantaneous bandwidth and nonlinear distortion, are identified. To address these issues, mitigation strategies and future research directions are also outlined, supporting the advancement of RAR-aided wireless systems.