# Low-Frequency Communication Based on Rydberg-Atom Receiver
## 5 Conclusions  
In this study, we demonstrated that Rydberg atoms in an electrode-embedded cell can receive signals modulated using 2 FSK, OOK, and BPSK. Among these, 2 FSK exhibited slightly better performance in terms of noise resistance, SNR stability, and high-fidelity transmission of digital images, achieving a peak PSNR of 70 dB. Our findings suggest that Rydberg-atom receivers are not only highly sensitive but also robust in low-frequency communication. However, several challenges remain to be addressed before Rydberg-atom receivers can be widely deployed in real-world applications. The alignment and stability of the probe and coupling lasers are critical for maintaining the Rydberg state; however, these lasers can easily drift out of alignment, requiring frequent recalibration. The long-term stability of the laser frequencies requires improvement to ensure consistent performance over extended periods. The system's overall sensitivity to environmental factors, such as temperature fluctuations and electromagnetic interference, poses significant challenges for practical deployment. Additionally, although Rydberg-atom receivers offer high sensitivity and are significantly smaller than conventional low-frequency receivers, they still lag behind the best-performing conventional low-frequency receivers in terms of sensitivity.  
Owing to their compact size and high sensitivity, Rydberg-atom receivers present exciting prospects for scalability in real-world applications, particularly those with strict  
Figure 10: Reception of black-and-white and color images. (**a**) Original black and white image; (**b**) received black and white image; (**c**) original color image; (**d**) received color image.  
space and performance constraints. In satellite telemetry, the ability to detect weak signals with high fidelity can significantly enhance data transmission efficiency. In underground communication, Rydberg-atom receivers can offer reliable signal detection even in noisy and interference-prone environments. Additionally, their robustness against environmental factors makes them well-suited for emergency response systems, where reliable communication is crucial. Future work will focus on further optimizing these features to enhance their practical applicability and explore new use cases in emerging technologies, including quantum communication and 6G networks.  
Conceptualization, Y.X. and M.S.; methodology, Y.X. and W.D.; software, Y.X.; validation, J.Z.; formal analysis, M.L.; investigation, J.Z. and W.D.; resources, M.S.; data curation, M.L.; writing--original draft preparation, Y.X.; writing--review and editing, M.L.; visualization, Y.X.; supervision, W.D.; project administration, M.S.; funding acquisition, M.S. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the National Natural Science Foundation of China (U2341211), and Key Programs of the Chinese Academy of Sciences (RCJ)-145-24-16), and the Director Fund of Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences.  
Data are contained within the article.  
The authors acknowledge the Key Laboratory of Space Utilization, Technology and Engineering Center for Space Utilization for the use of experimental equipment.  
The authors declare no conflicts of interest.