Study On Electromagnetic Interference Of Board Level And System Level In Vehicle Multimedia Navigation System

The high-speed chip is an important part of the vehicle electronic system.With the development of integrated circuit(IC)chip technology,the chip size is getting smaller and smaller.Besides,more and more pins of chip lead to increased layout and wiring density of the printed circuit board(PCB).Moreover,the speed of chip is increasing.The transmission line on each high-speed circuit network is likely to become the transmitting antenna,which generates electromagnetic radiation to other electronic devices,causing electromagnetic compatibility(EMC)problems.The EMC simulation technology has the outstanding advantages of high efficiency,low cost and flexibility.Therefore,the simulation technology has great guiding significance for researching the EMC of board level and system level.Firstly,in the aspect of electromagnetic simulation theory for the vehicle electronic system,the electromagnetic simulation theory of finite element algorithm based on Maxwell’s equation is expounded.Besides,the calculation formula of electric field finite element method excited by current source is derived.Moreover,the convergence basis of finite element adaptive meshing technique in engineering is given.Secondly,in the optimization of simulation technology of the vehicle multimedia navigation system,the modeling and electromagnetic simulation of the system are studied.In this studiy,the electromagnetic interference(EMI)simulation technology of board level and system level are deeply analyzed.At the same time,the accuracy and applicability of each simulation technique are comprehensively analyzed.The research shows that the average deviation of field-circuit co-simulation is about 4 d BμV using the simulation program with intergrated circuit emphasis(Spice)model of chip,which is the best choice for evaluating PCB and system design.Finally,in the aspect of EMI suppression of vehicle multimedia navigation system,the mechanism of EMI generated by the system is analyzed.Meanwhile,some measures to suppress the EMI of the system are studied by simulation technology.According to the standard experiment,the effectiveness of the measures to reduce the EMI of the vehicle electronic system is verified.The experiment shows that after replacing the original clock on the PCB with an external clock,the EMI on the PCB drops to1.3 d BμV,meeting the GMW 3097 standard.