VSB调制解调

CA 码的产生，以及自相关，互相关函数，画出自相关互相关图（MATLAB语句简单易懂，适合新手）(CA code generation, as well as autocorrelation, cross-correlation function, drawn from the correlation cross correlation diagram (MATLAB statement, easy to understand, suitable for novices))

说明：  多径参数干扰下的ofdm系统的matlab仿真代码，可供学习(Matlab simulation code of OFDM system under multipath parameter interference can be learned)

说明：  此代码为4ASK发送调制与接收解调的通信系统，为主要代码(Communication system of 4ask transmitting modulation and receiving demodulation)

一种基于服务质量的SMAC协议，对无线传感器的QOS的MAC协议代码。做了分析。(SMAC based on the quality of service agreement)

103转modbus协议C程序，支持多个485端口并能够配置(103 turn modbus protocol C program, more than 485 ports and supports the ability to configure)

A 2x2 multiple-input multiple-output (MIMO) architecture using dual-polarized antennas (DPAs) is considered with orthogonal frequency division multiplexing (OFDM). The performance of DPAs is evaluated for adaptive polarization (AP) transmission techniques in time-varying multipath channels impaired by polarization mode dispersion (PMD) and polarization-dependent loss (PDL). AP transmission techniques considered include power gain maximization, polarization dispersion minimization for interference avoidance, polarization multiplexing with waterfilling, and a suboptimal multiplexing strategy that enables direct recovery of the polarization multiplexed streams, thereby simplifying the design of the receiver. Measured time-varying dual-polarized channel realizations from mobile-to-mobile experiments are used to estimate the capacity, diversity, and interference avoidance performance of the adaptive approaches.

说明：  产生随机信号，采用4fsk调制方式通过一个水声信道，再采用非相干解调(Generate random signal, use 4FSK modulation to pass through an underwater acoustic channel, and then use incoherent demodulation)

区别去传统的傅里叶变换，对于非平稳信号而言，分数傅里叶变换是一个较好的方法，本程序实现了分数傅里叶变化对LPF类信号的估计。具有较高的学习价值(Different from the traditional Fourier transform, for non-stationary signals, fractional Fourier transform is a better method, this program implements the fractional Fourier transform to estimate the class LPF signal. It has higher learning value)

航空航天通信技术一般采用模拟通信的频率调制和数字通信的移相键控调制方法。这有利于充分应用信道带宽和能源。频率调制是在一定程度上改变载波或副载波的频率来传输信息的调制方法。移相键控调制是利用载波或副载波的相位跳变来传输信息的调制方法。移相键控又分二相移相键控、四相移相键控和多相移相键控，其中以四相移相键控和八相移相键控调制方法的效率较高(Aerospace communications technology commonly used analog communication of frequency modulation and the digital communication phase shift keying modulation method. This is helpful for making full use of channel bandwidth and energy. Frequency modulation is changed to some extent carrier or subcarrier frequency to transmit information modulation method. Phase shift keying modulation is the use of carrier or subcarrier phase jump to transmit information modulation method. Phase shift keying and binary phase shift keying, four phase shift keying and multiple phase shift keying, of which four phase shift keying and eight phase shift keying modulation method of high efficiency )

说明：  基于稀疏贝叶斯学习的窄带信号波达方向估计，实测有用，亲测有效！(Based on the sparse Bayesian learning, the narrow-band signal direction estimation is useful, and the pro-test is effective!)