High-speed NLA-16QAM modulator for satellite communications

摘要

Designed a NLA-16QAM modulator to transmit satellite data at the speed of 900Mbps, working in X band. NLA-16QAM signal is generated by combining two QPSK signals other than conventional QAM. Splitting a serial stream of data bits to four parallel streams, and then convert each two of them from absolute codes to relative codes. Enter them into two QPSK modulators respectively. After each QPSK signal passes through its own saturated power amplifiers, 6dB difference between the power levels of them. Entering them into a power synthesizer to obtain 16QAM signal. NLA-16QAM modulation can not only enhance spectral efficiency, but also can utilize precious energy in satellites.