digitalsystem

此源代码为链路级仿真平台下，基于scm信道模型的信道空间相关性仿真分析(This source code for link level simulation platform based on SCM channel model channel space correlation simulation analysis)

OFDM系统在QPSK与16QAM调制下，误码率比较程序，希望对大家有一定用处(OFDM system with 16QAM QPSK modulation, error rate procedures, We hope to have some use)

说明：  最基础的检测概率；虚警概率；漏检概率与门限的关系。(Energy detection;Single threshold.)

这个matlab代码仿真了M-QAM的传输。M的取值不同，调制方式分别为4QAM，16QAM，64QAM等。传输信道为AWGN信道，能出误码率曲线。(The matlab code simulation of the M-QAM transmission. The value of M, the modulation mode of 4QAM, 16QAM, 64QAM. The transmission channel is AWGN, the BER curves.)

研究考虑多普勒频移fd情况的LFM调频目标回波特性(Study considers the case of Doppler shift fd target echo characteristics LFM FM)

说明：  实时声音采集，双通道采集声音信号，并且进行降噪处理和FFT变换(Real time sound acquisition)

说明：  LMS自适应信道均衡程序以及学习曲线绘制，程序为matlab代码。(LMS adaptive channel equalization process and the learning curve drawing, procedures for the matlab code.)

生成常见的混沌映射，用于混沌扩频码的设计。应用三种量化方法，比特量化、门限量化以及模2量化。重点计算其相关性能，自相关以及互相关，得到相关图像。计算序列的游程、平衡度。(To generate common chaos maps and use them to design the chaotic spreading sequences. We applied three kinds of quantization methods with bit queantization, threshold quantization and mod 2 quantization. We emphasized on the calculating the correlation performance on auto-corrrelation and cross-correlation and plotted their images.)

基本通信信号的产生于识别，AM FM 2ASK 2FSK 2PSK QPSK的产生。（时域图 频域图 基带信号频谱 ）以及分类的识别方法仿真模型(Basic communication signal arising from the recognition, the AM FM 2ASK 2FSK 2PSK QPSK generation. (Time-domain diagram frequency domain Figure baseband signal spectrum) and the classification of simulation models of the identification method)

无线通信中，设备到设备技术的控制可控制，提高抗干扰能力，频谱利用率(In wireless communications, control of equipment-to-equipment technology can be controlled to improve anti-interference ability, spectrum utilization)