【摘要】 针对煤矿井下狭窄巷道无线通信环境的特殊性，提出了一种基于天线选择技术的MIMO-OFDM系统模型。系统结合空时编码技术，分析了低信噪比情况下的系统性能，推导了接收天线公式，利用矩阵更加直观地表示天线信号集合。基于煤矿井下巷道空间狭窄的低功率低信噪比实际情况，从信道容量与误码率2方面进行分析，研究了接收天线数量L_R=1和L_R=2情况下系统性能。仿真结果表明，经过天线选择后的2发1收、2发2收系统分别得到了约2.8 dB与3.5 dB的系统增益，提出的MIMO-OFDM 2发2收系统在低信噪比情况下能够拥有较好的误码率。更多还原

【Abstract】 A MIMO-OFDM system model based on antenna selection technology is presented for the particularity of wireless communication environment in narrow roadways in coal mines. Combining with space-time encoding technology, the system performance under low signal-to-noise ratio is analyzed,and the formula of receiving antenna is deduced. The matrix is used to more intuitively represent the antenna signal collection. Based on the actual situation of low power and low signal-to-noise ratio with narrow space in underground coal mine roadway, the number of receiving antennas L_R=1 and L_R=2 in the system performance are studied from two aspects of channel capacity and bit error rate. The simulation results show that the 2-send-1-receive and 2-send-2-receive systems with antenna selection get about 3 dB and 3.5 dB system gains, respectively. The proposed MIMO-OFDM 2-send-2-receive system can have a good bit error rate at low signal-to-noise ratio.更多还原