论文部分内容阅读
在数字卫星通信中,广泛采用的是PSK调制方式,在对相应的解调系统进行调试、测试时,需要有PSK调制方式的信号源。对这一信号源的要求是相位误差小、工作性能稳定可靠、测试功能齐全等。为了满足上述要求,我们制作了采用ECL电路的全数字式多功能PSK信号源。产生PSK信号的一般方法是采用环形调制器。对于BPSK信号,用这一方法还是可以的,但用来产生QPSK信号就很难做到令人满意了。由图1见,QPSK信号是由两个
In digital satellite communications, the PSK modulation method is widely used. When the corresponding demodulation system is debugged or tested, a PSK modulation signal source is required. The requirements of this signal source is a small phase error, stable and reliable performance, test functions and so on. In order to meet the above requirements, we have produced a fully digital multi-function PSK signal source using ECL circuits. A common method of generating PSK signals is to use a ring modulator. This method is still acceptable for BPSK signals, but it is difficult to achieve satisfactory QPSK signal generation. Seen from Figure 1, the QPSK signal is composed of two