GMSK的调制解调原理分析

1. 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。请清楚的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S-function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。并请回答：证明自己用计算机产生的经典谱是正确的可能方法。 (Doppler spectrum of radio channel 1, please answer the following questions (1) In some wireless channel, radio channel Doppler shift will cause the output signal aliasing. Please clearly describe aliasing for various reasons )

说明：  ldpc编码的matlab实现，供大家参考(Matlab implementation of LDPC coding for your reference)

8psk解调代码，采用garner 符号时钟同步(8PSK demodulating code with garner symbol clock synchronization)

MPLS简介,主要介绍了MPLS的基本原理(Description of MPLS)

csma tutorial for begginers with graphics explantaion

matlab程序，包括QPSK,16QAM,64QAM等多种调制方式的调制解调(modulation and demodulation of QPSK,16QAM and 64QAM etc.)

说明：  energy efficiency code for cognitive radio

一个串口通讯的源码，自定义的通讯协议，与切纸设备连接(A serial communications source, since the definition of communication protocols, and cutting equipment to connect)

说明：  STC单片机多机连级串口程序可实现.416路控制. 串口和485都可以使用、 一个程序可以用在26块控制板上，通过拔码开关给板子编号，每块板可以过滤分析所接收到不同的代码。进行继电器的动作，能返回数据，因使用定时器发送返回，不会阻塞或者代码错乱、可以 用在中控，物联网，等各种控制场合。修改代码后，能达到上千路的控制。(STC single-chip microcomputer multi-level serial port program can realize 416 channel control. Serial port and 485 can be used. One program can be used on 26 control boards. Each board can filter and analyze different codes received by numbering the boards with the pull-out switch. Relay operation can return data, because the timer is used to send the return, it will not block or code confusion, and can be used in central control, Internet of things, and other control occasions. After modifying the code, it can achieve thousands of control.)

Modbus4J源代码，方便大家查看具体的协议内容(Modbus4J.rar is a file that describes how control the PLC by Java language)