Analysis Of Electromagnetic Compatibility For Vehicle-mounted Multifunctional Radio Frequency Sensor

When the development of science and technology goes toward the age of the intelligence,the automobile industry initiates the exploration of intelligent automobile immediately.The progress of intelligent automobile has put forward the new requirement of vehicular electronic communication system,such as the sharp increasing amounts of vehicular antenna,the diversification of the variety of vehicular antenna and the increment in the range of operating frequency,which makes the electromagnetic environment surrounding the vehicular antenna system more complex.The effect of the complex electromagnetic environment on the vehicular antenna system and the coupling interference among the vehicular multi-antennas seriously impair the operation of vehicular electronic communication system.For refraining from the degradation of vehicular antenna systems,the reasonable and effective analysis of electromagnetic compatibility of vehicular antenna system matters much.Based on the scientific research project “Simulation and analysis of electromagnetic compatibility of vehicular antenna system”,the thesis discussed and analyzed the electromagnetic compatibility of vehicular antenna system with the microwave and antenna theory and electromagnetic numerical computation method.The main content contains two parts: the coupling effect among the vehicular multi-antennas and the coupling effect of the external radiation field on the vehicular antenna system.1.For the study of the coupling effects among the vehicular multi-antennas,the principle of near-field region coupling is analyzed theoretically,and the effect of various platforms on the coupling degree between two antennas in the near-field region is discussed.Then,the coupling degrees between two antennas,placed in free space,above the infinite ground and finite conductor plane respectively,are calculated by the means of method of moment.Meanwhile,the principle of far-filed region coupling is analyzed with the help of Friis transmission formula,and the effect of the finite conductor plane on the coupling degree between antennas is analyzed theoretically.The coupling degree between antennas is simulated using fast multipole method.Finally,the coupling degrees among vehicular antennas above the vehicle platform are simulated in the use of equivalent source method and shooting and bouncing ray method.2.For the study of the coupling effect of external radiation field on the vehicular antennas system,HEMP is chosen as the external radiation source,and the time domain waveform and the energy-spectrum frequency of the HEMP are studied.The calculation approaches of the electromagnetic response function are theoretically discussed and simulated under the circumstances of in-band response and out-of-band response,respectively.Finally,the electromagnetic response functions of the vehicular antennas placed above the vehicle platform are simulated by equivalent source method and shooting and bouncing ray method,and the responses of electromagnetic coupling of the vehicular antennas system exposed to HEMP radiation field are calculated in detail.