【作者】 郭胜祥；

【导师】 邱扬；

【作者基本信息】 西安电子科技大学 ， 机械电子工程， 2008， 硕士

【摘要】 车载平台空间狭小,多部、多种工作模式电台上装在同一车辆上,会带来严重的电磁兼容问题(EMC),它已经影响到通信系统的正常工作,因此,对车载无线设备间电磁干扰进行分析和预测,并提出相应的抑制技术具有重要的意义和工程应用价值。本文针对车载电台主要的三种工作模式:普通定频、跳频(FH)和直接序列扩频(DS),分别提出了共址干扰预测方法。在普通定频工作模式下,运用耦合干扰裕度模型,结合实验室现有的仿真软件,建立了共址安全带宽的预测模型,并分析了如何运用测试获得收发信机特性曲线的方法;在跳频工作模式下,针对跳频频点的随机性,结合跳频瞬时安全带宽,建立了基于概率的分段频分组网的预测模型;在直接序列扩频工作模式下,通过对干扰容限的分析,借鉴普通定频安全带宽的预测方法,分析了频分直接序列扩频的等效安全带宽预测。通过在相关项目中的应用,验证了上述各预测模型的正确性。最后,本文在分析共址干扰造成的接收机减敏现象的基础上,探讨减敏对通信距离的影响,并就车载通信平台的特点,提出了一些具体地抑制共址干扰的措施。从而为车载通信系统的电磁兼容设计提供了工程指导。更多还原

【Abstract】 The space of vehicle platform was small, a number of and a variety of operating modes of radios in the same vehicle, it will bring serious problem of electromagnetic compatibility (EMC), which has affected the normal operation of communications systems, Therefore, the analysis and prediction of electromagnetic interference among the wireless equipments and putting forward the corresponding suppression is of great significance and value engineering.The prediction method of the co-site interference is respectively put forward for the three operating models: fixed-frequency, frequency-hopping (FH) and Direct Sequence Spread Spectrum (DS). In the fixed-frequency mode, using interference margin in model, and combined with existing laboratory simulation software, a co-site guard-band prediction model is established, and gave a briefing on how to use the method of test for transceiver’s characteristic curve; in the frequency-hopping mode, for the random frequency hopping, through the introduction of instantaneous co-site guard-band, the prediction mode about frequency division network is established base on probability; in the Direct Sequence Spread Spectrum mode, through the analysis of interference tolerance, referencing the prediction method of co-site guard-band in the fixed-frequency mode, the prediction of equivalent guard-band base on frequency division Direct Sequence Spread Spectrum system is analyzed, Through the application in related projects, the accuracy of the above prediction models is validated.Based on the analysis of the desensitization of receivers caused by co-site interference, the impact between desensitization and communication distant is discussed in this paper. And the measures of reducing co-site interference are put forward, aim at characteristics of vehicular platform. So, it provides engineering guidance for the design of EMC in vehicular communication systems.更多还原