Satellite-Communications-Research-Trends-and-Open

说明：  给程序给出了功率放大器预失真过程中的时延同步问题。(This codes provides the time delay synchronization in the process of power amplifier predistortion.)

说明：  ：载波频率偏移是OFDM系统实现的关键问题之一。分析了OFDM 系统载频偏移估计的2 种算法，即利用循环前缀和训练序列方法。它们均为最大似然估计方法。分别讨论了它们的基本 思想、实现方法和仿真结果。可以看出基于循环前缀算法复杂度较小，精度不高，而基于训练序列 的算法有较高的估计精度，但降纸了系统传输效率。(Abstract：Carrier frequency ofset is one of the key problems in OFDM system．Two foundational methods 。cycling prefix—based and training sequence—based algorithms。to estimate OFDM carriers~equency ofset are analyzed．Then it discusses their basic thoughts。implementing methods and simulation resuits． Finally。merits and demerits of every algorithm are supposed．It concludes that the cycling prefix— based algorithm has less complexity and less precision。and that the training sequence—based algorithm has better estimation performance at the cost of transmission efficiency．)

DRM(Digital Radio Mondiale)系统采用OFDM调制方式， 引入了先进的信源信道编码和调制技术，使得AM波段的音频广播质量大大提高，在保持现有10kHz带宽时接近了FM广播的质量[5](DRM (Digital Radio Mondiale) system uses OFDM modulation, the introduction of advanced source-channel coding and modulation techniques, making AM-band audio broadcast quality greatly improved, while maintaining the existing 10kHz bandwidth close to the quality of FM broadcasting [5])

winner+项目信道校正数据，大尺度、小尺度、视距、非视距信道参数校正测量数据(winner+ project channel calibration data, large-scale small scales, sight, NLOS channel parameter calibration measurement data)

pwm整流器的建模仿真，感应双馈发电机系统的仿真，复化三点Gauss-lengend公式求pi。( Modeling and simulation pwm rectifier Simulation of doubly fed induction generator system, Complex of three-point Gauss-lengend the Formula pi.)

mimo document problems

Analysis and Simulation Model of Physical Carrier Sensing in IEEE 802.11 Mesh Networks

智能天线波束赋形算法研究,对天线中的波束形成算法分析的非常深入。(Smart antenna beamforming algorithm, in the antenna beam to form a very in-depth analysis of the algorithm.)

主要是实现调制识别，区分几种常用的数字调制信号。含有两个文件夹 其一为特征参数的仿真；其二为正确识别率的仿真。文件夹key feature simulink中： 运行程序会得到各特征参数之间区分图 从图中可看到特征参数的有效性，见图。 文件夹classification rate simulink中：运行main.m文件 可以得到正确识别率 见图。(It is mainly to realize modulation recognition and distinguish several commonly used digital modulation signals. The simulation of two folders is one of the characteristic parameters, and the second is the simulation of the correct recognition rate. In the folder key feature Simulink: The running program will get the validity of the feature parameters that can be seen from the diagram, as shown in the diagram. Folder classification rate Simulink: running the main.m file can get the correct recognition rate.)

说明：  document qpsk vhdl code