AD1

实现LDPC编码和译码，利用C语言编写，在matlab环境中画性能曲线。(Realize encoding and decoding of LDPC codes)

The PCI Local bus concept was developed to break the PC data I/O bottleneck and clearly opens the door to increasing system speed and expansion capabilities. The PCI Local bus moves high speed peripherals from the I/O bus and places them closer to the system’s processor bus, providing faster data transfers between the processor and peripherals. The PCI Local bus also addresses the industry’s need for a bus standard which is not directly dependent on the speed, size and type of system processor. It represents the first microprocessor independent bus offering performance more than adequate for the most demanding applications such as full-motion video.(The PCI Local bus concept was developed to breakthe PC data I/O bottleneck and clearly opens the doorto increasing system speed and expansion capabilities.The PCI Local bus moves high speed peripheralsfrom the I/O bus and places them closer to the system sprocessor bus, providing faster data transfersbetween the processor and peripherals. The PCI Localbus also addresses the industry s need for a bus standardwhich is not directly dependent on the speed, size and type of system processor. It represents thefirst microprocessor independent bus offering performancemore than adequate for the most demandingapplications such as full-motion video.)

说明：  基于modbus rtu封装的通讯协议，很好用(Communication protocol based on Modbus RTU encapsulation)

VB的CRC16校验源码，调试成功，程序简单。(The CRC16 checksum VB source code, debugging successful, the program simple.)

接收端采用的算法和程序流程与发送端发送的OFDM符号的帧结构有关系。具体的帧结构，以及定时估计，频偏估计，剩余误差跟踪的算法可参考算法说明文档。这里对程序的流程进行说明。 首先根据短训练字的特性进行相关运算，进行信号到达检测，当检测到相关值大于门限一定次数后，认为有信号到达。然后根据长训练字的特性，进行相关运算，进行OFDM符号FFT窗口起始位置的估计。估计出FFT窗口的位置后，先在时域进行小频偏的估计，将两个长训练字进行小频偏补偿后，进行FFT运算，根据FFT运算的结果进行整数倍频偏的估计。这些参数估计完成后，就可以进行数据解调了。先对数据部分进行完整的频偏补偿，然后根据估计的FFT窗口位置进行FFT运算得到频域的数据，进行解调。然后在对应于导频的子载波位置上提取出导频信息，根据导频信息估计出剩余定时误差以及剩余的信道响应误差，将误差量送入环路进行跟踪。当收到所有数据后，重新回到信号到达检测状态，进行下一次信号到达的检测和信号接收。 (good)

说明：  非常好的OPC服务器源代码 免费的 没有时间限制(Very good OPC server source code for free no time limit)

加拿大人发表的关于周跳探测,实现了实时的双频周跳探测和修复(cycle-slipsfromCanada)

实现windows和linux之间的通信 或者 window间通信 linux间通信(Communication between windows and Linux or communication between Linux communication between window)

USB通信编程，获取USB设备信息，如果编译不通过，你需要下载NTDDK中的hidsdi.h 和 hid.lib文件等。(USB communication programming，get the USB devices informateion ,if there have link errors,you have to download the header files hidsdi. H, the library file hid. Lib,etc in the NTDDK.)

实验了界面组态和串口通信，完成了界面显示，通过串口变化功能(Experimental interface configuration and serial communication, completed through the serial interface display change function)