Low frequency communication based on Rydberg-atom receiver

Low frequency communication has a wide range of applications in the fields of satellite detection, underground mining, disaster relief. Rydberg atom sensor has rapidly developed in recent years, capitalizing on its calibration-free SI-traceability, large polarizabilities and transition dipole moments. A Rydberg atom sensor is capable of sensitively detecting electric field signals from DC to THz. In this work, we demonstrate low frequency communication using Rydberg atoms in a vapor cell with two parallel electrode plates inside. Three modulations, BPSK, OOK, and 2FSK, are used for the communication by Rydberg atom receiver near 100kHz. We have measured the SNR of the modulated low frequency signal received by Rydberg atoms at various emission voltages. Meanwhile, we have demonstrated IQ constellation diagram, EVM and eye diagram of the demodulated signal at different symbol rate. The EVM is measured to be 8.8% when the symbol rate is 2Kbps, 9.4% when the symbol rate is 4Kbps, and 13.7% when the symbol rate is 8Kbps. The high-fidelity digital color image transmission resulted in a peak signal-to-noise ratio of 70dB. This study proves that Rydberg-atom receiver can finely work in low frequency communication.