quadrature amplitude modulation

For high order QAM ( Quadrature Amplitude Modulation) signals, the residual square error of CMA ( Constant Modulus Algorithm) is unacceptably large and the convergence rate of MMA ( Multi Modulus Algorithm) is too slow.

对于高阶QAM信号，常数模算法的收敛误差不为零，而多模算法的收敛速度慢。

A method to identify the modulation levels of M-ary Quadrature Amplitude Modulation ( M-QAM) and M-ary Amplitude shift keying ( M-ASK) was developed to rapidly and automatically identify the modulation levels of digitally modulated signals at low signal-to-noise ratios ( SNR).

为了快速自动识别低信噪比下的数字幅度调制进制，提出了一种识别M进制正交幅度调制（M-QAM）和M进制幅度键控（M-ASK）的调制进制的方法。

Simulation and Performance Analysis on the System of Quadrature Amplitude Modulation and Demodulation Based on the Known Channels

基于已知特性信道的QAM系统的仿真和性能分析

Then the results are analyzed and compared in order to design the applicable system, which are valuable to the system of quadrature amplitude modulation and demodulation.

通过对得到的仿真结果进行比较和分析，在理论上，得到合理设计QAM系统的方法.这些分析方法和得到的结论对工程中的QAM调制解调系统实现具有一定的价值。

Both Quadrature Amplitude Modulation ( QAM) and Low Density Parity Check Code ( LDPC) are widely used in such fields as wireless communication, wired television transmission and satellite communication.

正交幅度调制（QAM）和低密度奇偶校验码（LDPC）技术应用于很广泛的领域，如无线通信、有线电视传输、卫星通信等领域。