对于水声信道估计的大量参考文献

基于matlab的QPSK调制与解调程序(QPSK modulation and demodulation)

完成Zero-forcing,MMSE的均衡器以及带feedback的据衡器 比较各自的误差率的matlab代码(Complete Zero-forcing, MMSE equalizer with feedback of data Weighing respective error rate matlab code)

In this paper, we present and analyze efficient frame synchronization and frequency offset compensation scheme with ternary sequences for an orthogonal frequency division multiplexing (OFDM) system in Rayleigh fading channels. Frame synchronization is an essential procedure for normal operation of the OFDM system because of sensitivity to synchronization errors. And when there are frequency offsets in OFDM frame, the loss of orthogonality occurs and the interference problem among several subcarriers is introduced. These fact leads to the requirement for joint implementation of the frame synchronization and frequency offset compensation.

this code simulate pure aloha .

无线信道建模，路径损耗及正态阴影模型源代码，可出图，(Path loss Wireless channel modeling)

说明：  智能语音小车标准程序，已经测试通过了的。完全没有问题。(The standard program of intelligent voice car has passed the test. No problem at all.)

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)

微波实验设计，设计波导滤波器和波导等功率分配器(Microwave experimental design, waveguide filter design and waveguide power divider etc.)

Sample code in VB.NET for calculate and check CRC (Modbus specification). Supported both string format (like MSComm) and bytes array(like DCB).

voice transformation good algo