正交振幅调制

本文的调相信号的类内识别算法与调相和正交振幅调制信号的类间识别算法都是基于高阶累积量的。

In this thesis , the identification algorithms of MPSK and MPSK / QAM are both base on high order cumulants .

正交振幅调制（QAM）是一种相位和振幅联合控制的数字调制技术，它不仅可以得到更高的频谱效率，而且可以在限定的频带内传输更高速率的数据。

Quadrature amplitude modulation is a joint-controlled digital modulation technology of phase and amplitude , which not only has higher spectrum efficiency , but also has higher speed of data transmission in limited frequency band .

提出一种适用于石油测井领域高速电缆遥测通信系统，基于自适应均衡和QAM正交振幅调制技术的调制解调器的原理和实现方法。

This paper proposed a modem based on adaptive equalization and QAM in oil logging for cable telemetry communication systems with high date rate .

分析仿真结果表明，盲侦察系统能够识别出如MASK、MFSK、MPSK及正交振幅调制信号的信息隐藏位置，且识别率较高。

The simulation results prove that the blind reconnaissance system can make reconnaissance with MASK 、 MFSK 、 MPSK and QAM , and identify the hiding location with high identification .

近年来，移动通信技术专家非常重视正交振幅调制（quadratureamplitudemodulation，缩写为QAM）技术，它是根据载波的不同幅度和相位代表不同的编码符号，利用了这样的特点来传递信息。

Quadrature Amplitude Modulation is a modulation mode which Mobile Communication Technology expert attaches much importance to in recent years . The information is transmitted on the basis of amplitude and phase in QAM . Different amplitude and phase represent different symbol of information .

正交振幅调制（QAM）具有频带利用率高、抗噪声能力强、调制解调系统简单等优点，目前在数字广播、宽带接入等通信系统获得广泛应用。

Quadrature amplitude modulation ( QAM ) is one kind of high band efficiency , noise immunity modulation technology . Its modulation and demodulation system is simple . For these advantages , QAM is widely used in digital broadcasting and broadband access communication systems .

概述多电平正交振幅调制（MQAM）调制解调的一般原理，介绍一种能有效提高频谱利用率的变速率调制技术，并论述它在EDSL系统中的具体应用。

The principle of MQAM modulation and demodulation was outlined , and variable rate QAM , which could improve the spectral efficiency distinctly , was introduced in detail , its particular application in EDSL System was also discussed in this paper .

通过对传统载波数据传输方式的分析，介绍一种新型电力线载波数据传输装置，采用八进制正交振幅调制替代频移键控调制，实现上音频复用传输1200bps数据。

With the analysis of traditional data transmitting method in power line carrier channel , this paper introduces a new transmission device which adopts octal quadrature amplitude modulation instead of frequency shift keying to achieve the requirement of multi-purpose 1 200 bps data transmitting .

振幅调制是信号处理中的关键步骤，它直接决定了输出发射器的工作效率和质量，可采用的振幅调制方案有双边带振幅调制、单边带振幅调制以及正交振幅调制等。

Amplitude modulator is a committed step in the signal processing , it has determined to output working efficiency and quality of the launcher directly . Adoptable amplitude modulate scheme have double sideband amplitude modulator , single sideband amplitude modulator and quadrature amplitude modulator etc.