随机构造的LDPC码的编译码过程

说明：  分别用M序列gold序列正交gold序列设计直接序列扩频通信系统并分析误码率(Using m-sequence gold sequence orthogonal gold sequence to design DSSS communication system and analyze the bit error rate)

在VC++6.0中用MSComm控件编程，可以实现串口接(used in VC 6.0 MSComm programming, serial port access can be achieved)

提供通讯录成员的查询、增加、更新及删除等功能。(Provide contacts membership query, add, update, and delete functions.)

OFDM调制发射和接收仿真，考虑两种调制方式，16qam及qpsk调制，使用LS信道估计和频域均衡(OFDM modulation transmission and reception simulation, considering two modulation modes, 16QAM and QPSK modulation, using LS channel estimation and frequency domain equalization.)

无线信道建模，路径损耗及正态阴影模型源代码，可出图，(Path loss Wireless channel modeling)

the satellite communication this paper introduced

说明：  SC-FDE相位噪声比较(SC-FDE phase noise comparison)

本文作的工作是利用信号仿真器仿真GPS数字中频信号，并借助这些仿真信 号完成对GPS信号的捕获和跟踪性能的研究。(This article is for the use of GPS signal simulator simulation digital IF signal, and make use of these simulation signal completion of the GPS signal acquisition and tracking performance study.)

高斯信道下DFT-S OFDM 理论误码率仿真代码及其仿真结果图(DFT-S OFDM theoretical BER simulation code and simulation results Figure in Gaussian channel )

说明：  2. 关于无线信道的多普勒谱，请回答以下问题： (1) 在某些无线信道中，多普勒频移会引起无线信道输出信号的混叠。请描述产生混叠的各种原因； (2) 无线信道中的多普勒谱有一种经典谱(classic spectrum)，请解释产生这种谱形状的机理； (3) 请用Simulink工具编写代码(S-Function方式)，产生一单径瑞利信道，其多普勒谱为经典谱，其中移动速率为120km/h。并请描述：自己用计算机产生的经典谱是正确的依据。(2. Regarding the doppler spectrum of the wireless channel, please answer the following questions: (1) in some wireless channels, doppler frequency shift will cause aliasing of the output signals of the wireless channel.Describe the various causes of aliasing; (2) there is a classic spectrum in the doppler spectrum in the wireless channel, please explain the mechanism of producing this spectrum shape; (3) please use Simulink tool to write code (s-function mode) to generate a single-path Rayleigh channel, whose doppler spectrum is the classical spectrum, in which the moving rate is 120km/h.And please describe: your own computer generated classical spectrum is the correct basis.)