Dynamic_Subchannel_and_Bit_Allocation_in_multiuse

针对MIMO-OFDM系统中期望最大化(EM)信道估计算法在高信噪比(SNR)下带来的误差地板(EF)现象,且OFDM符号的数据传输效率随发射天线数的增加而明显降低,提出一种改进的高效EM信道估计算法。该算法首先引入一种准确的等效信号模型并推导出一种修正的EM算法,改善了EM算法在高SNR下的性能 在多个OFDM间利用相位正交导频序列来提高数据传输效率,同时进行联合信道估计以提高估计性能。仿真实验验证了所提算法具有更高的信道估计性能和更高的数据传输效率。(For multiple-input multiple-output with orthogonal frequency division multiplexing(MIMO-OFDM) systems,the error floor(EF) phenomenon at high signal noise rate(SNR) was induced by the expectation maximum(EM) channel estimation algorithm.In addition,the data transmission efficiency was declined obviously with the increasing number of transmit antennas.According to these problems,an improved and efficient EM channel estimation algorithm was pro-posed.Firstly,an accurate and equivalent signal model was introduc...)

采用QPSK调制方式实现OFDM，在simulink上搭建的仿真模块，可以很好的学习OFDM，验证通过。(Achieved using QPSK modulation OFDM, built on the simulink simulation module can be good learning OFDM. )

vb 和pmac控制卡的简单通讯，实现电动，正转反转停止，及下载文件(vb to pmac commucation)

说明：  电池管理系统当中使用的一线通，节省成本 本人已测试成功 效果显著(Battery management system in the use of the first line, saving costs)

说明：  可以比较两种信道估计算法的BER和均方误差(The BER and mean square error of the two channel estimation algorithms can be compared)

This program generates BPSK signal waveforms and plot the power spectrum of unfiltered BPSK.

仿真图是速度、距离、幅度三维图像，插值与拟合的matlab实现，计算两个矩阵之间的欧氏距离。( FIG simulation speed, distance, amplitude three-dimensional image, Interpolation and fitting matlab implementation, Calculation of the Euclidean distance between the two matrices.)

标准接口1-5V转换成4-20mA程序，应用于标准传感器接入(Standard Interface 1-5V Converting 4-20mA Program for Standard Sensor Access)

使用NMEA0183的gps服务程序原码(use of a GPS NMEA0183 service program source)

这是一篇介绍数字下变频中抽取滤波器设计的文章 我觉得很有指导意义，在此共享(this arcitle is dicrible the DDC design,very good)