txxxxxx

说明：  根据卫星EIRP值、接收系统G/T值等参数仿真了卫星通信的上下行及总链路预算的matlab程序 及论文《卫星传输链路的计算与应用》(uplink and downlink margin budget)

说明：  主要研究无线通信系统中，调制信号的载波同步问题，利用锁相环技术实现同步的matlab仿真(This paper mainly studies the carrier synchronization of modulated signal in wireless communication system, and realizes the MATLAB simulation of synchronization by using phase-locked loop technology.)

OFDM同步算法的仿真matlab，用于LTE系统的OFDM技术，获得时域同步有很多算法，该文件提供了部分matlab的代码(OFDM synchronization algorithm simulation matlab, for the LTE system OFDM technology, access to time-domain synchronization, there are many algorithms, the document provides part of the matlab code)

这是一款安卓软件，在之前上传的第一版的基础上，完善了家居控制功能，增加了聊天室、手机电脑实时记录、画板功能等。适用于安卓开发大作业，也可供大创参考(This is Smart Home version2.0)

实现绘制信号的功率谱，两重自相关，滤波后时域，滤波器，频谱图，信号时域图以及自相关函数图等功能(The functions of drawing signal power spectrum, double correlation, filtering time domain, filter, spectrum, signal time domain and autocorrelation function diagram are realized.)

Abstract—In this paper, we study the joint estimation of inphase and quadrature-phase (I/Q) imbalance, carrier frequency offset (CFO), and channel response for multiple-input multipleoutput (MIMO) orthogonal frequency division multiplexing (OFDM) systems using training sequences. A new concept called channel residual energy (CRE) is introduced. We show that by minimizing the CRE, we can jointly estimate the I/Q imbalance and CFO without knowing the channel response. The proposed method needs only one OFDM block for training and the training symbols can be arbitrary. Moreover when the training block consists of two repeated sequences, a low complexity two-step approach is proposed to solve the joint estimation problem. Simulation results show that the mean-squared error (MSE) of the proposed method is close to the Cramer-Rao bound (CRB). Index Terms—MIMO OFDM, CFO, I/Q imbalance, channel estimation.

说明：  产生正弦信号时域波形及频谱，并通过希尔伯特滤波器。其中希尔伯特滤波器有两种产生方式，一是使用MATLAB自带的FDAtool；二是程序编写。(The time-domain waveform and spectrum of sinusoidal signal are generated and passed through Hilbert filter. There are two ways to generate Hilbert filter, one is to use FDAtool in MATLAB, the other is to write programs.)

这是一个基于空时分组编码的MIMO_OFDM通信系统的仿真设计。 此系统包括QPSK调制解调，IFFT调制，空时编解码，基于训 练符号的信道估计等通信模块。(This is a simulation design of a MIMO_OFDM communication system based on space time block coding. The system includes QPSK modulation and demodulation, IFFT modulation, space-time codec, and training based on training. A communication module, such as the channel estimation of a symbol.)

用C语言编写的LDPC译码程序，希望对大家有用(Using C language LDPC decoding process, in the hope that useful)

说明：  IEC 60870-5-101 通信规约英文版规范(IEC 60870-5-101-2003 Telecontrol equipment and systems Part 5-101 Transmission protocols)