星座图

用改进的星座图扩展法降低OFDM信号峰均功率比

Reducing the OFDM peak-to-average power ratio with improved constellation extension

载波频偏对OFDM系统影响有两大方面：一方面它使得星座图发生了旋转；

Carrier offset has two main influence on OFDM systems : on one hand it makes the constellation rotates ;

全数字多星座图、可变符号率QAM调制器

An All-Digitized Multimode and Variable Symbol Rate QAM Modulator FIGURE

基于对星座图分形的Qam信号识别

Qam signals recognition based on fractal research of constellation

通过仿真观察到调制与解调信号的波形，星座图以及QAM信号功率谱密度曲线，并对仿真结果进行了分析。

The modulating wave . Constellation Diagram and power spectrum density curve is observed by simulation .

给出了利用信号星座图的QAM信号调制方式识别技术。

The modulation recognition technique of QAM signal by the constellation diagram is given in this paper .

一种基于星座图聚类的MQAM识别方法

MQAM Recognition Based on Research of Constellation Clustering

并在保证系统可靠性要求下，针对不同的信道衰落条件选取合适的QAM星座图级别。

An adaptive constellation levels were selected for different channel states to increase throughput under the constraint of the system 's BER .

理论分析了OFDM毫米波的色散性能，研究发现虽然由于色散的影响，每个OFDM子载波都有一个相移，但是经过相位均衡后，可以很清晰的得到接收星座图。

According to the result , although every sub-carrier of OFDM signals after transmission had a phase shift caused by dispersion , we can obtain a clear received constellation after phase equalization .

仿真结果表明，该算法较CMA算法有较快的收敛速度，较小的稳态均方误差，并且可以纠正相位偏移引起的星座图旋转；

Simulation results demonstrate that the new algorithm increases convergence rate , decreases steady-state mean square error and corrects rotation of phase .

于是在分析一种星形商分编码QAM的基础上，将其在平坦瑞利衰落信道上的误码率公式推广到更多元的星座图，并对星座图进行了优化。

A star-QAM with quotient coding is analyzed and its symbol error rate in flat rayleigh fading channel is generalized to larger constellations .

提出了基于星座图建立最大误码率和APD之间映射关系的方法。

Thirdly , based on the constellation diagram , I present a new method to establish a relationship between the APD and BER .

经过仿真，从星座图、误码率（Bit-Error-Rate，BER）及信噪比（Signal-to-NoiseRatio，SNR）损失等角度对采样频率偏差的影响做了揭示和验证。

In the simulation , constellation , Bit-Error-Rate ( BER ) and Signal-to-Noise Ratio ( SNR ) performance degradation are analyzed taking into account the effect of sampling frequency offset .

对QAM调制的两种星座图的性能进行了分析比较，并得到星型QAM信号的最佳星座图。

The two properties of QAM constellation map have been analyzed and compared , and receive satellite signals in the best-QAM constellation map . 3 .

本论文对改进后的结构进行复杂度对比、采样速率对比和能源消耗对比，并仿真得到了各种结构的脉冲响应、频率响应和星座图，所设计的各种实现结构均在FPGA上编程下载成功。

The Comparison of improved the structures is maked in sampling rate , hardware complexity and the of energy consumption . The impulse response , frequency response and the constellation diagram are produced by simulation . It has realize for using FPGA .

针对此问题修改了传统的M-QAM软解调方案，同时在发送端可以得到CSI不准确程度的反馈的前提下，提出了一种方形M-QAM星座图的优化方法。

The conventional soft demodulation method is modified to develop an optimized square M-QAM modulation method using feedback of the CSI noise power .

提出将扫频算法与简化星座图算法（RC-DD）相结合应用于QAM载波恢复中。

The frequency weeping algorithm and decision-directed of reduced constellation ( RC-DD ) algorithm are together used in QAM carrier recovery .

文中用最陡下降法和变步长自适应算法进行了计算机仿真，给出了频偏跟踪曲线和BPSK的星座图。

Steepest descent algorithm and variable step size adaptive algorithm designed by us are used in computer simulations . The tracking curve , MSE , and constellation of BPSK are presented .

分析了在含有高斯白噪声的Rayleigh衰落信道中，矩形星座图MQAM、圆形星座图MQAM的传输误码性能，给出相应的误码率计算公式，并进行计算机数值分析。

A transmission error code performance for square MQAM and star MQAM modulation schemes on the AWGN Rayleigh fading channel is analyzed . The corresponding BER formulas and computer aided numeric results are also given .

该系统具有软件无线电的优点，利用系统控制UI，可任意选择合适系统的工作频率、调制方式及调制等参数，可实时观察信号波形图、频谱图、星座图以及眼图。

The system has the advantages of software radio . Using the system control UI can optionally select the system operating frequency , the modulation type and parameters , observe waveform diagram , spectrum , constellation diagram and eye diagram of the received signal in real-time .

星座图法在二叠纪末期Albaillella属放射虫化石形态分类中的应用

Application of constellation graph to the morphological classification of albaillella ( radiolaria ) from latest Permian

接着对MQAM信号模糊c均值聚类，将得到的星座图与理想星座图模型进行比较，通过引入新的代价函数实现MQAM调制方式的识别。

Then the signals are processed by fuzzy C-means clustering . The recovered constellations are then matched with standard constellations and classified using an improved cost function . Thus , MQAM signals can be classified when match them with standard constellation patterns .

介绍了移动通信系统对调制技术的要求，分析了现代数字调制技术的特点，详细分析了QAM调制解调的原理、主要参数和调制信号星座图的分布结构。

Introduced the demand of modulation technologies for mobile communication system , and then analyze the modern digital modulation characteristics , the principle of QAM modulation and demodulation , the main parameters and the modulation signal constellation diagram of the distribution structure .

在输入信号信噪比已知的基础上，结合信号星座图，分析了在Nakagami衰落信道中采用不同数量的发射和接受天线时系统的误码率。

Based on the known input SNR , this article analyses the bit error rate ( BER ) on Nakagami Fading Channel which adopts the multi-input and multi-output antennas system combines with the signal constellation graph .

Pearson相关星座图将22个优势种分为4个生态种组，各生态种组内的种有相同的资源利用方式和生态要求，各种组间有互相转化和演替的趋势。

The dominant species were divided into 4 ecological groups by using Pearson constellation diagram and we concluded that the species in the same ecological groups had the same way of utilizing resources and the species in different group had the trend of transform and succession .

根据Spearman秩相关星座图，将20个优势种划分为4个生态种组，各生态种组内的种具有相似的生态适应性，而组间则表现出明显的差异性；

Based on the Spearman constellation diagram , 20 dominant species were divided into four ecological species groups . The species in the same ecological species groups had similar ecological adaptability to habitats and those in different groups had apparent differences .

针对MPSK信号的分类问题，提出一种新的基于高阶统计量的分类特征.新特征对MPSK信号星座图的平移、尺度和相位旋转变换具有不变性，并可抑制有色和白的加性高斯噪声。

A new feature based on higher order statistics is proposed for the classification of MPSK signals , which is invariant with respect to constellation translation ( shift ), scale and rotation , and can suppresses the color or white additive Gaussian noise .

针对QPSK信号的星座图以及位同步点的恒模特性，给出了位同步点模值方差最小的同步方法，并详细设计了位同步电路。

Besides , according to constellation diagram of QPSK signal and the constant mode characteristic of bit synchronization point , it puts forward a synchronous method , in which the variance of mode is the minimum ; in addition , it particularly designs synchronous circuit .

Viterbo最初的球形译码仅能处理整数实星座图信号，本文将其推广，可适合于复星座图信号。

The original sphere decode algorithm of Viterbo can only tackle the real constellation , and this dissertation adapts it to tackle complex constellation with any shape .

本文研究高速水声通信中正交幅度调制系统的盲均衡理论与算法，主要工作如下：（1）通过研究多模辅助算法的均衡原理，得到了一类基于星座图特点改进的多模辅助算法（CMAMA）。

In this paper , quadrature amplitude modulation system blind equalization algorithm in high-speed underwater acoustic communication is analyzed and the main work is as follows : ( 1 ) By studying the principle of MAMA , improved a class algorithm ( CMAMA ) based on the constellation features .