为评估TD_SCDMA下行链路联合检测接收机的性能，使用MATLAB软件进行链路仿真，本程序主要是实现用户QPSK基带调制、扩频、加扰、形成时隙、形成子帧、以及进行脉冲形成滤波，通过加性高斯白噪声信道和瑞利衰落多径信道，信道估计、联合检测等几个主要过程，整个仿真都是在基带进行的。-Link simulation to assess the performance of the TD_SCDMA Downlink joint detection receiver using MATLAB software, this program is the main user QPSK baseband modulation, spreading, scrambling to form a slot to form a sub-fr a me, as well as for pulse formation filter, through an additive white Gaussian noise channels and Rayleigh fading multipath channel, channel estimation, the joint detection of several major process, the entire simulation in the baseband