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In recent years, the number of portable mobile terminal users is increasing with improvement of the wireless communication environment. In addition, mobile multimedia services also bring the increase of wireless traffic and lack of spectrum resources. As a technique for efficient spectrum use, spectrum sharing receives much attention. It dynamically assigns a spectrum channel from a larger area network such as WiMAX to smaller area networks such as WiFi-based wireless LANs and achieves to increase the total wireless communication capacity of this area. In a case where all providers are cooperative, the spectrum sharing can be realized easily and improve user throughput in average. In another case where providers are not cooperative, some spectrum trading methods based on auction theory had been proposed.

生成2KHz和8KHz的混合信号,使该信号通过上述滤波器,观察滤波前后的波形变化和频谱分布情况,(The mixed signal of 2KHz and 8KHz is generated, and the waveform changes and spectrum distribution before and after filtering are observed through the filter.)

说明：  实现UWB仿真，用于实现自动追踪定位，即卡尔曼滤波算法(Implement UWB simulation for automatic tracking and positioning, namely Kalman filter algorithm)

估计接收到的直扩信号的载频，码速率，以及扩频增益(Estimate the carrier frequency, code rate, and spread spectrum gain of the received DSS signals)

语音信号处理的fft算法 编程实现了FFT算法，运用编写的FFT程序对信号进行FFT计算和还原，待分析的信号是一段音乐，与Matlab的FFT函数进行了比较并设计系统页面 (FFT algorithm for speech signal processing FFT programming algorithm, the use of the preparation of the FFT program to calculate and restore the signal FFT, the signal to be analyzed is a piece of music, and the Matlab function of the FFT and the design of the system page)

利用Matlab实现的二维TDOA定位算法仿真程序。。(2D TDOA algorithm implemented by Matlab simulation program. .)

MIMO指多输入多输出，MIMO技术大致可以分为两类：发射/接收分集和空间复用。传统的多天线被用来增加分集度从而克服信道衰落，具有相同信息的信号通过不同的路径被发送出去，在接收机端可以获得数据符号多个独立衰落的复制品，从而获得更高的接收可靠性。这种技术往往要结合多天线技术，而多天线技术在移动通信中得到了广泛的研究。(MIMO refers to Multiple Input Multiple Output, MIMO technology can be broadly classified into two categories: transmit/receive diversity and spatial multiplexing. Traditional multi-antenna was used to increase the degree of diversity to overcome channel fading, the signal with the same information through different paths have been sent in the receiver-side data symbols can be multiple independent copies of the decline, which was higher reception reliability. This technology often have to combine multi-antenna technology, and multi-antenna technology in mobile communication has been widely studied.)

Cooperative MIMO matlba source code

说明：  4. 试说明卷积编解码的工作原理： (1) 使用Simulink仿真卷积编码，并用Viterbi译码的方法进行解码，其中的编码、译码全部是自己编写代码(S-Function方式)，不是调用Simulink的已有编码、译码函数。 (2) 请在加性白高斯噪声信道中，画出比特信噪比与误码率的关系曲线。(4. Try to explain the working principle of convolutional codec: (1) Simulink was used to simulate convolutional coding, and Viterbi decoding method was used for decoding. The coding and decoding were all written by oneself (s-function method), rather than calling the existing coding and decoding functions of Simulink. (2) in the additive white gaussian noise channel, please draw the curve of the relationship between bit signal-to-noise ratio and bit error rate.)

在光纤通讯仿真中，产生QPSK，16QAM，64QAM信号，并添加激光相位噪声和自发辐射噪声(In optical fiber communication simulation, QPSK, 16QAM, 64QAM signals are generated, and laser phase noise and spontaneous radiation noise are added.)