OFweek维科网

基于MATLAB的QPSK信号调制技术及其频谱分析

4PSK信号是两个载波正交的2PSK信号的合成。所以，可以仿照2PSK相干检测法，用两个正交的相干载波分别检测两个分量 a和b，然后还原成二进制双比特串行数字信号。此法称作极性比较法（相干解调加码反变换器方式或相干正交解调法） 判决器是按极性来判决的。
OFweek维科网

基于MATLAB的QPSK信号调制技术及其频谱分析

5.1理想信道下基本QPSK仿真系统 在理解了QPSK调制解调的原理下，利用上面介绍的matlab软件构建1.一个理想信道下基本QPSK仿真系统,仿真结果包括a.基带输入波形及其功率谱 ；b.QPSK信号及其功率谱；c.QPSK信号星座图 从上图可以看出，QPSK信号在理想信道上的调制 ...
TechRepublic

Implementation of Digital QPSK Modulator by Using VHDL/MATLAB

The modulators are the basic requirement of the communication systems they are designed to reduce the channel distortion & to use in RF communication hence many type of carrier modulation techniques ...
EDN

Modulation roundup: error rates, noise, and capacity

(c) Capacity in bits per second per Hertz vs. Bit to Noise Ratio (Capacity vs Eb/No) (d) Bit Error Rate vs. Bit to Noise Ratio (BER vs Eb/No) Symbol Error Rate vs. Es ...
EDN

Complex modulation comes to optical fiber

The demand for greater data throughput seems endless, and it is accelerating faster than many people expected, creating bottlenecks in fiber-optics networks. Digital transmissions of 100 Gbps, which ...