M2_FSK_Digital_Modulation

Asynchronous Transfer Mode (ATM) is a connection-oriented, packet-switched technology. The packets that are switched in an ATM network are of a fixed length, 53 bytes, and are called cells. The cell size has a particular effect on carrying voice traffic effectively. The ATM Adaptation Layer (AAL) sits between ATM and the variable-length packet protocols that might use ATM, such as IP.

希尔伯特变换测试，使用希尔伯特变换对信号处理，相位偏移90°(The Hilbert transform test uses Hilbert transform to process the signal with a phase shift of 90 degrees)

说明：  采用Mackay构造H矩阵的LDPC码仿真。(LDPC code simulation of H matrix constructed by Mackay)

实现基于STBC的MIMO_OFDM通信系统在不同信噪比情况下接收端的误比特率的仿真。发射端包括基于基带调制、空时编码、导频插入、IFFT、串并合并以及添加循环前缀；接收端包括去除循环前缀、取出导频估计信道、FFT运算以及并串合并，空时解码等。仿真中采用QPSK、空时编码采用4*3的复正交空时编码矩阵。OFDM子载波数为100，每个子载波传输66个符号，每个符号2比特。IFFT长度为512个符号。发射天线为3个接收天线为2个。(The BER simulation of MIMO_OFDM communication system based on STBC under different SNR is realized. The transmitter includes baseband modulation, space-time coding, pilot insertion, IFFT, serial-parallel combination and adding cyclic prefix; the receiver includes removing cyclic prefix, extracting pilot estimation channel, FFT operation, parallel-serial combination, space-time decoding, etc. The complex orthogonal space-time coding matrix is used in QPSK and space time coding in 4*3. The number of OFDM subcarriers is 100, and each subcarrier transfers 66 symbols with 2 bits per symbol. IFFT is 512 symbols in length. The transmitting antenna is 3 receiving antennas, 2.)

语音信号的采集与处理，数字信号处理课设，能量谱分析计算,小波包分析提取振动信号中的特征频率。( Acquisition and Processing of the speech signal, digital signal processing class-based, Energy spectrum analysis and calculation, Wavelet packet analysis to extract vibration signal characteristic frequency.)

实验串口通信，专用于电子科技大学中山学院的实验箱，有兴趣的同学可以选的下载哦(Experimental serial communication, dedicated to the electronic science and technology university of Zhongshan college of experimental box, interested students can choose to download oh)

实现16QAM完整的调制解调系统，包括基带信号串并转换，星座图映射，升抽样成形滤波，升采样半带滤波，数字上变频，功放的多项式非线性效应，加性高斯白噪声信道，接收端下变频，降采样，匹配滤波，绘制接收端星座图。(16QAM modulation and demodulation realize the complete system, including the baseband signal string and conversion, constellation mapping, sampling shaping filter liter, half liter sampling with filtering, digital up-conversion, amplifier polynomial nonlinear effects, additive white gaussian noise channel, the receiver end down-conversion, down-sampling, matched filtering, draw the receiver constellation.)

说明：  通过matlab来实现带通滤波，可自由设置带通范围，滤波效率高，结果精确(Through MATLAB to achieve band-pass filtering, the band-pass range can be set freely, the filtering efficiency is high and the result is accurate)

用于手机模组中显示屏上，用来点屏的初始化代码(On the display module for mobile phones used to point screen initialization code)

多路复用写的一个可收发数据的串口应用程序(Write a multiplexer can send and receive serial data applications)