OFDM-Simulink-

多径条件下基于WSF的均匀圆阵幅相误差自校正(WSF-based multipath conditions of uniform circular array amplitude and phase error self-correction)

contains a document about antenna array fundamentals, equation for estimation of array parameters, antenna polar plots. etc

说明：  turbo均衡 ，用于多径信道提升性能，map、SISO算法，PSK和QAM调制(Turbo Equalization, for multipath channel to improve performance, map, SISO algorithm, PSK and QAM modulation)

朋友写的C++645通讯程序，支持645-1997与645-2007,支持自已组帧程序自动添加校验码通讯，可以增加数据标识定义，里面还有部分关于费控通讯代码，挺好，拿来分享(Friend write C++645 communications program to support the 645-1997 and 645-2007, to support their own group the frame program automatically adds the checksum communications, can increase data identifies the definition, there is also a section on the fee control communications code, good for them and share)

介绍了三点垂直线阵被动定位的原理. 结合矢量水听器测得的方位角和高低角及到达 阵元间的时延差, 建立了三维坐标下的状态方程和观测方程.运用扩展卡尔曼滤波算法, 研究了该系统的目标运动分析问题. 通过蒙特卡洛模拟仿真试验, 结果表明上述方法具有较高的定位性能,有较强的使用价值. (Introduced three vertical linear array passive location principle of vector hydrophone. Combining the measured azimuth angle and pitch angle and arrival time delay difference between array elements, establish the three-dimensional coordinates of the state equation and observation equation. Using the extended Calman filter algorithm, on the target motion analysis by Monte Carlo simulation. Test, results show that the method has high positioning performance, has the strong use value.)

这是在uwb系统中，用TOA定位法的的整个系统的仿真程序源码 (This is a simulation program source code for the entire system in uwb systems, TOA positioning method)

随机方法构造的LDPC码，码长可变，无四环(random ldpc,code length can be changed)

Multiple input multiple output techniques combined with orthogonal frequency division multiplexing (MIMO-OFDM) provide a promising approach for wireless systems. However, a serious drawback of the OFDM system is the high peak-toaverage power ratio (PAPR), which may severely affect the power efficiency of RF power amplifiers. In this paper, we propose a simple method to reduce the PAPR of MIMO-OFDM signals based on the use of unused subcarriers. Instead of processing the signals at each transmitter separately, a peak cancelling signal is generated at one antenna and is then applied to all the others with only simple modifications. Simulation has shown that a minimum 2 dB reduction in PAPR can be achieved for all transmit signals using this approach. As the signal processing is nearly all done at a single transmitter, repetition of the operations at each transmitter is avoided, and therefore the overall cost of the system can be significantly reduced.

说明：  5. 在三条径的瑞利信道中，对于直接序列扩频： (1) 请设计DS-CDMA一种具体的码分导引辅助的信道估计方法，接收机分别采用等均益合并、最大比合并。用Simulink进行仿真，画出比特信噪比与信道估计均方误差的关系曲线和比特信噪比与误码率的关系曲线。 (2) 设频率已经同步，请设计DS-CDMA一种具体的单停顿滑动相关时间同步方法，用Simulink进行仿真，画出比特信噪比与捕获概率的关系曲线。 (3) 设时间已经同步，请设计DS-CDMA一种具体的频率同步方法，用Simulink进行仿真，画出比特信噪比与频率同步误差的关系曲线。(5. In three-path Rayleigh channel, for direct sequence spread spectrum: (1) please design a specific code division navigation aided channel estimation method for ds-cdma, and adopt equal-beneficial combination and maximum ratio combination for receivers respectively.Simulink is used to simulate and draw the relationship curve between bit SNR and channel estimation mean square error and the relationship curve between bit SNR and bit error rate. (2) assuming that the frequency has been synchronized, please design a specific single-stop sliding correlation time synchronization method ds-cdma, Simulink simulation, draw the relationship between the bit SNR and the acquisition probability curve. (3) if the time has been synchronized, please design a specific frequency synchronization method ds-cdma, Simulink simulation, draw the relationship between the bit SNR and frequency synchronization error curve.)

opnet仿真实例，里面有一些现成的例子可供使用。(opnet the simulation, which has some ready-made examples available.)