Air-interface-physical-link-layer

说明：  前已提出的频谱感知方法主要包括匹配滤波器检测、 能量检测、 循环平稳特征检测以及多分辨率频谱感知. 这些方法均为单节点感知方法.然而，在阴影和深度衰落情况下， 单个节点的感知结果并不可靠， 因此， 需要对多个节点的感知结果进行融合，以提高检测可靠性， 即协作感知技术. 文献采用“或” 准则对各个 CR 感知结果进行融合. 文献则提出了基于 D-S 证据理论的协作频谱感知算法，虽然该算法的性能比“或” 准则或“与”准则要好， 但需要存储大量历史信息， 算法的计算复杂度也很高. 文献中分析了采用似然比检测(likelihood ratio test， LRT) 的软判决与采用“与” 准则的硬判决的性能， 结果表明采用软判决的协作感知性能更优(Previously proposed spectrum sensing methods mainly include matched filter detection, energy detection, cyclostationary feature detection and multi-resolution spectrum sensing. These methods are all single node sensing methods. However, in the case of shadow and deep fading, the sensing results of single node are not reliable, so, It is necessary to fuse the sensing results of multiple nodes to improve the detection reliability, i.e. cooperative sensing technology. In the literature, "or" criterion is used to fuse the CR sensing results. In the literature, a cooperative spectrum sensing algorithm based on D-S evidence theory is proposed. Although the performance of the algorithm is better than "or" criterion or "and" criterion, a large amount of historical information needs to be stored, The computational complexity of the algorithm is also very high. In the literature, the performance of the soft decision based on the likelihood ratio test)

Ethercat协议栈代码示例,基于C语言，已经调试通过(The example for Ethercat slave protocol)

qpsk信号插入导频，使用升余弦滤波器，利用导频估计信道，在simulink中仿真(inset pilot in QPSK signal, use square root raised cosine filters in simulink)

VB写的一个简单的服务器与客户端程序，可以进行简单的本机通讯。经修改可以用于双机通讯。(VB to write a simple server and client, can be simple local communication. Modified can be used for two-machine communication.)

文章针对无线传感器网络(WSN)节点定位算法DV-Hop的节点间距离沽计误差对定位准确度影响较大的问题，提出一种基于LS-SVR(最小二乘支持向量回归机)的定位算法L-LSSVR. (Aiming at solving the problem of the significant influence of distance estimation error onlocation accuracy of DV-Hop in Wireless Sensor Networks (WSN), a new node localizationmethod based on LS-SVR (L-LSSVR) is proposed.)

实现了lfm信号的仿真，可以对其频谱和时域波形进行分析，并且仿真了其模糊函数，可以分析其雷达性能。(The simulation of LFM signal is realized, and its spectrum and time domain waveform can be analyzed, and its ambiguity function can be simulated to analyze its radar performance.)

这是一个完整的OFDM通信系统仿真代码。包括信源编码信源调制，信道编码，信道估计，峰均抑制比等。实际程序可用直接运行。(This is a complete OFDM communication system simulation code. Including the source modulation source coding, channel coding, channel estimation, peak to average ratio suppression. The actual procedure can be run directly.)

一个详细讲述卡尔曼滤波的ppt，通过它可以学习有关卡尔曼滤博，和机器人自主定位的知识( Kalman filter detailed ppt, through which you can learn more about Bo Kalman filter, and knowledge of robot autonomous localization )

实验了界面组态和串口通信，完成了界面显示，通过串口变化功能(Experimental interface configuration and serial communication, completed through the serial interface display change function)

GD32F库函数，各种外设，gpio等等(gd32 library v2.0.0 gpio ..)