中文说明：
实现基于STBC的MIMO_OFDM通信系统在不同信噪比情况下接收端的误比特率的仿真。发射端包括基于基带调制、空时编码、导频插入、IFFT、串并合并以及添加循环前缀；接收端包括去除循环前缀、取出导频估计信道、FFT运算以及并串合并，空时解码等。仿真中采用QPSK、空时编码采用4*3的复正交空时编码矩阵。OFDM子载波数为100，每个子载波传输66个符号，每个符号2比特。IFFT长度为512个符号。发射天线为3个接收天线为2个。
English Description：
The simulation of bit error rate (Ber) at the receiver of MIMO communication system based on STBC under different SNR is realized. The transmitting end includes base-band modulation, space-time coding, pilot insertion, IFFT, string merging and adding cyclic prefix; the receiving end includes removing cyclic prefix, taking out pilot estimation channel, FFT operation and parallel-to-serial merging, space-time decoding and so on. QPSK and 4 * 3 Complex Orthogonal space-time Coding Matrix are adopted in the simulation. The OFDM subcarrier number is 100, each subcarrier transmits 66 symbols, each symbol 2 bits. IFFT IS 512 symbols long. The transmitting antenna is 3 and the receiving antenna is 2.