802.11p标准下DSRC抑制车间信道衰落技术研究

This project takes the inter-vehicle communications of DSRC under the standard of 802.11p as the research object, surrounding and researching how to improve the capability of suppressing the inter-vehicle channel fading closely. After pointing out that the actual inter-vehicle communication channels have fast time-varying fading as well as frequency-selective fading, at first, we propose a new algorithm of spectral decomposition of matrix, combining with the estimation method proposed by Fernandez to make the new scheme track the changes of the current fast time-varying fading channels more accuracy under the premise of the computational complexity is not high. Meanwhile, a subcarrier grouping algorithm is put forward on the basis of the method of spectral keying proposed by the project group, making it further reduce the redundancy caused by the spectral keying under the premise of suppressing the frequency selective fading effectively in inter-vehicle channel, and apply them to the time-varying frequency selective fading channels proposed in this project..During the process of the concrete research，at first, we simulate it by MATLAB in two different channel models and implement it on FPGA, then we download it to the development board to test its performance to finally realize the gain of the system after simulation is basically in agreement with the gain after testing it on the development board in order to achieve the goal of improving the ability of DSRC to combat channel fading under the existing standard and make some contributions to the theoretical research of wireless local area network.

本项目以802.11p标准下DSRC车间通信作为研究对象，紧密围绕如何改善其抑制车间信道衰落的能力展开研究。在指出实际车间信道同时具有快时变衰落和频率选择性衰落之后，首先提出了一种新的矩阵谱分解算法，再结合上Fernandez提出的估计算法，使得新方案在计算复杂度不高的前提下能更精确地跟踪当前快时变衰落信道的变化；同时在课题组已经提出的频谱键控调制方案的基础上，提出了一种子载波分组算法，使其在有效抑制车间信道中的频率选择性衰落的前提下进一步减少频谱键控所带来的数据冗余，并将它们用于本项目所提出的快时变频率选择性衰落信道中。.在具体研究过程中，首先采用MATLAB在两种不同信道模型下进行建模仿真并进行FPGA实现，然后下载到开发板中进行性能测试最终实现仿真后与实测后的增益基本吻合, 以期达到提高现有标准下DSRC抑制信道衰落能力的目的，同时也为无线局域网的理论研究做出一些贡献。

本项目主要研究802.11p标准下DSRC在车间通信过程中对车间信道衰落抑制能力的改善。首先对车辆行驶在高速公路、城市街道、郊区乡村、山区等典型的信道场景中所遇到的信道衰落情况进行了具体分析之后，指出实际车间信道同时具有快时变衰落和频率选择性衰落，DSRC只有能够同时对车间信道中的快时变衰落和频率选择性衰落进行抑制，才能从根本上提高车间通信的信号传输质量；随后提出一种矩阵谱分解STA信道估计方案，来提高DSRC抑制快时变衰落的能力，同时提出一种基于子载波分组的频谱键控调制方案，来进一步减少算法所带来的冗余，并将它们用于本项目所提出的快时变频率选择性衰落信道中。通过采用MATLAB对DSRC系统在两种不同信道模型下进行建模仿真并进行FPGA实现后不难发现，采用本项目的研究方案可以显著降低DSRC的误码率性能，同时该方案可以用于实际的系统中，具有良好的可行性与应用价值。.在研究本项目的过程中一共发表学术论文9篇(其中6篇为SCI检索论文)，获得授权发明专利4项，正在受理的发明专利6项。共培养通信领域的博士研究生2名、硕士研究生4名。