Abstract We propose a Rydberg atom-based receiver for amplitude-modulation (AM) reception utilizing a dual-tone microwave field. The pseudo-random binary sequence (PRBS) signal is encoded in the basic microwave field (B-MW) at the frequency of 14.23 GHz. The signal can be decoded by the atomic receiver itself but more obvious with the introduction of an auxiliary microwave (A-MW) field. The receiver’s amplitude variations corresponding to microwave field are simulated by solving density matrices to give this mechanism theoretical support. An appropriate AM frequency is obtained by optimizing the signal-to-noise ratio, guaranteeing both large data transfer capacity (DTC) and high fidelity of the receiver. The power of two MW fields, along with the B-MW field frequency, is studied to acquire larger DTC and wider operating bandwidth. Finally, the readout of PRBS signals is performed by both the proposed and conventional mechanisms, and the comparison proves the obvious increment of DTC with the proposed scheme. This proof-of-principle demonstration exhibits the potential of the dual-tone scheme and offers a novel pathway for Rydberg atom-based microwave communication, which is beneficial for long-distance communication and weak signal perception outside the laboratory.
Abstract We propose a Rydberg atom-based receiver for amplitude-modulation (AM) reception utilizing a dual-tone microwave field. The pseudo-random binary sequence (PRBS) signal is encoded in the basic microwave field (B-MW) at the frequency of 14.23 GHz. The signal can be decoded by the atomic receiver itself but more obvious with the introduction of an auxiliary microwave (A-MW) field. The receiver’s amplitude variations corresponding to microwave field are simulated by solving density matrices to give this mechanism theoretical support. An appropriate AM frequency is obtained by optimizing the signal-to-noise ratio, guaranteeing both large data transfer capacity (DTC) and high fidelity of the receiver. The power of two MW fields, along with the B-MW field frequency, is studied to acquire larger DTC and wider operating bandwidth. Finally, the readout of PRBS signals is performed by both the proposed and conventional mechanisms, and the comparison proves the obvious increment of DTC with the proposed scheme. This proof-of-principle demonstration exhibits the potential of the dual-tone scheme and offers a novel pathway for Rydberg atom-based microwave communication, which is beneficial for long-distance communication and weak signal perception outside the laboratory.
We present a Rydberg atom-based receiver with amplitude modulation (AM) technique for the fifth-generation (5G) millimeter-wave wireless communication in a five-level85Rb atomic coherent system. The carrier microwave (C-MW) field at frequency of 24.12 GHz, corresponding to the 5G millimeter-wave wireless communication band, is encoded by AM technique, and then decoded by Rydberg atom-based receiver with the assistance of an auxiliary microwave (A-MW) field. An atomic response to the C-MW field linking to the signal-to-noise ratio (SNR) of decoded signal, which plays a prerequisite role in 5G millimeter-wave wireless communication with large data transfer capacity, is obtained by investigating the optimal powers of probe laser, coupling laser, and A-MW field. Also, an appropriate AM frequency of 10 kHz, which has an influence on the data transfer capacity, is acquired with 54 dB SNR of decoded signal. Under the abovementioned experimental conditions, the maximum data transfer capacity of 82.5 kbit/s is achieved when the C-MW field power tends to saturate. The bandwidth of Rydberg atom-based receiver is determined as 3.5 GHz, and the instantaneous bandwidth is approximately 106.3 kHz. As a result, 5G signals on three waveforms are transferred with high fidelity, frequency recovery rate, and time synchronization to verify the performance of this receiver for an actual communication. This scheme provides an effective approach for realizing 5G millimeter-wave wireless communication with wide bandwidth, large data transfer capacity, and high fidelity.
Rydberg atoms have been extensively utilized in microwave measurement with high sensitivity, which has great potential in the field of communication. In this study, we discuss the digital communication based on a Rydberg atomic receiver under simultaneously coupling by resonant and near detuning microwaves. In addition, we verify the feasibility of the Rydberg atom-based frequency division multiplexing (FDM) in microwave communication. We demonstrate the principle and performance of the atom-based FDM receiver by applying amplitude modulation (AM) and frequency modulation (FM), respectively. To demonstrate the actual communication performance at different data transfer rates, we consider monochromatic images as an example. The experimental results show that the maximum acceptable data transfer rate of both AM and FM is about 200 kbps, whereas their maximum bit error rates (BER) is less than 5%. When compared with the traditional electronic receiver, this atomic receiver, which is compatible with FDM, has numerous advantages, such as small size, low power consumption, and high sensitivity. Furthermore, this receiver has a strong ability of anti-electromagnetic interference, and the signals transmitted do not interfere with each other in different channels.
The highly-excited Rydberg states are with a unique property of radio-frequency (RF) resonance, and Rydberg atoms at room temperature are promising for developing a broadband RF electric field sensor and relevant metrology standards. In this paper, the working mechanism of an atomic amplitude-modulation(AM) radio receiver is investigated in detail, and various factors affecting the communication quality are discussed. The modulation RF signal can be directly retrieved by measuring the transmission of a probe laser at resonance of rubidium D2 transition using a fast photo-diode detector, without any conventional demodulation process. Various communication experiments are tested at a 10.22 GHz carrier, and a modulation bandwidth of 1 MHz and an acceptable data transfer rate of about 1 Mbps have been achieved using current detection techniques. Owing to a potential high sensitivity and ultra-broadband capability of free-space RF field sensing, the quantum receiver has great significance compared with conventional electronics-based receivers, including but not limited to a weak signal, long-distance, and broadband communication in free space or via a fiber link.
Due to the exaggerated properties of highly excited atomic states, a Rydberg-atom-based microwave receiver holds the promise to achieve superior performances in microwave metrology and communication when compared to conventional antennas. However, developing long-distance communication applications based on Rydberg atomic receiver remains challenging, because it requires the simultaneous achievement of low bit error rate (BER), high symbol rate, and weak carrier amplitude. The key to tackle this problem is to encode the information with a proper scheme that maintains high sensitivity and robustness of the Rydberg atomic receiver. Here, we use Rydberg atom-based heterodyne detection for the reception of phase-modulated microwave field, and demonstrate more than one order of magnitude improvement in reception sensitivity compared to the previously investigated amplitude-modulation scheme. Therefore, we achieve low BER communication with high symbol rate of 12 k bit/s and weak carrier amplitude of $13\phantom{\rule{0.2em}{0ex}}\text{\ensuremath{\mu}}\mathrm{V}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ simultaneously. Furthermore, we also demonstrate that our scheme is compatible with frequency-division-multiplexing communication.
We demonstrate an atom-based amplitude-modulation (AM) receiver for digital communication with a weak continuous frequency carrier using a Rydberg AC Stark effect in a vapor cell and achieve the operating carrier frequency continuously from 0.1 GHz to 5 GHz at a single Rydberg state. A strong local oscillator (LO) field E LO acts as a gain to shift the Rydberg level to a high sensitivity region, and a weak carrier field E Carr keeps the same frequency with the LO field. The digital baseband signals are encoded onto the E Carr using the amplitude modulation technique with the different modulation frequency. The response of Rydberg atom to the baseband signal is probed via a Rydberg electromagnetically induced transparency (EIT). The measured instantaneous bandwidth of the system is about 230 kHz. To demonstrate the performance of our system for an actual communication, we consider a color image as an example, the received image displays that the bit error rate (BER) is less than 5% when the maximum data transfer rate is about 238 kbps. Meanwhile, our system shows the weak carrier field of E Carr ≥ 13.52 μ V/cm can be used for the practical communication with BER less than 5%. Our works break the limitation that EIT-AT based atomic receivers only operate at the near resonant frequencies of the Rydberg transitions, making this emerging of quantum technology close to the practical application with high sensitivity and broad bandwidth.
Abstract The Rydberg atomic receiver (RAR), characterized by its broad bandwidth, high sensitivity, traceability, and all-optical readout, has substantial potential in wireless communication. We implement the reception of amplitude-phase shift keying (APSK) modulated microwave signals using the RAR, where its self-demodulation capability, based on electromagnetically induced transparency (EIT) and Autler–Townes (AT) splitting, preserves amplitude and phase information for decoding and data recovery. The relationship between amplitude and phase encoding orders in different APSK schemes and the bit error rate (BER) is explored. Relative to conventional amplitude-shift keying (ASK), APSK extends the phase dimension to increase data capacity proportional to the number of phase states. Additionally, APSK allows control of symbol durations, and the impact of varying symbol durations on data recovery is assessed through image transmission. This work utilizes the self-demodulation capabilities of the RAR to implement APSK within a quantum framework, thereby providing new insights for advancing quantum sensing and communication applications.