说明：  （1） 分析QPSK调制、解调原理，并画出其系统框图； （2） 产生等概率且相互独立的二进制序列，作为待传输的信号，并画出其波形； （3） 进行8PSK调制，分别画出I、Q两支路信号经过乘法器后的波形以及8PSK调制波形；
((1) The principle of QPSK modulation and demodulation is analyzed, and the system diagram is drawn; (2) Generating equal probability and independent binary sequence as the signal to be transmitted, and drawing its waveform; (3) After 8PSK modulation, the waveforms of I and Q signals after multiplier and 8PSK modulation are drawn;)