基于所建立的Nakagami分布矿井巷道宽带统计分段信道模型,研究了在2.4 GHz和5.8GHz这2个典型UHF频段下正交频分复用调制技术在矿井巷道中的宽带无线通信性能.在相同的信噪比下,当原始数据速率固定和矿井巷道信道环境相同时,载波频率为5.8 GHz时OFDM系统的误码率性能较载波频率为2.4 GHz时好;载波频率为2.4 GHz和5.8 GHz的OFDM系统都具有良好的抗脉冲干扰特性;多普勒频移对矿井巷道OFDM系统的误码率性能有严重影响,对载波频率为5.8 GHz系统误码率性能的影响较2.4 GHz时严重.
Based on the multi-section Nakagami distribution statistical channel model of mine tunnel for wideband radio wave, the bit error rate (BER) performance of Orthogonal Frequency Division Multiplexing (OFDM) modulation at 2.4 GHz and 5.8 GHz in mine tunnel was investigated. According to the different root-mean-square (RMS) time delay of wideband radio wave along empty-straight or embranchment mine tunnel, the main parameters of OFDM modulation at 2.4 GHz and 5.8 GHz are designed. At the same signal-noise-radio (SNR), original data rate and wireless channel, the BER performance of OFDM at 5.8 GHz is better than that at 2.4 GHz for both empty-straight and embranchment mine tunnel. The OFDM modulation in mine tunnel shows good ability to resist impulse interference at both 2.4 GHz and 5.8 GHz. Doppler frequency offset has serious effect on the BER performance of OFDM modulation in mine tunnel. It affects the BER performance at 5.8 GHz more severe than that at 2.4 GHz. In the case of Doppler frequency offset, when the SNR is larger than 20 dB, the continuous increase of SNR can not improve the BER performance of the system significantly.