2025 Volume E108.B Issue 7 Pages 842-850
The application of Reconfigurable Intelligent Surface (RIS) technology in underground coal mines provides innovative solutions for enhancing mine safety and operational efficiency. This paper proposes a signal detection scheme for RIS channels in mines, utilizing adaptive filtering algorithms to design the RIS reflection array. By iteratively updating the reflection coefficient matrix, we minimize the mean square error between the error signal and the actual received signal. To accurately estimate the RIS channel in mines, we construct a minimum mean square error (MMSE) objective function based on pilot signals, providing a closed-form solution. At the receiving end, we employ a parallel interference cancellation (PIC) algorithm combined with space-time processing techniques to improve signal detection accuracy. Experimental results indicate that under ideal Rayleigh channel conditions, the PIC algorithm based on the RIS system can effectively reduce the BER of signals propagating within the tunnel, When SNR = 6 dB, the BER with RIS assistance is 3.77 × 10-2. Additionally, compared to higher-order QAM modulation, the system exhibits better error performance under lower-order QAM modulation. Furthermore, the performance of the system is further enhanced under OFDM-64QAM modulation; with RIS assistance, the BER using the PIC method is 7.44 × 10-4, meeting the fundamental communication requirements for underground operations. This research is significant for improving mine communication performance in complex multipath and electromagnetic interference environments and lays a theoretical and practical foundation for the application of 6G technology in mine environments.
