Research On Key Technologies Of Interference Anti-jamming Between High Speed Circuit Boards

Electronic equipment is constantly developing in the direction of miniaturization,high speed,and high frequency.While the processing speed and transmission rate of electronic weapon equipment have been rapidly improved,crosstalk problems caused by wiring layout and high-speed inter-circuit interference between high-speed circuit boards have become an important bottleneck hindering the rapid development of information weaponry.It is especially important to study the electromagnetic interference and signal transmission problems caused by the mismatch between the characteristic impedance of the interface and the termination impedance during the transmission between high-speed boards.This thesis analyzes the wiring layout theory and obtains several wiring optimization structures,including shortening the routing,properly setting the interface position,optimizing the bypass and power layout.In addition,the influence of the position error of the protective wiring center and the characteristic impedance of the guard line and the offset of the via hole on the crosstalk are also analyzed.Because the impedance mismatch of the connector often causes great interference to the interconnection between multiple high-speed circuit boards,this paper also simulates the connector and simulates the influence of various geometric parameters of the connector on the noise suppression effect.At the same time,PCB trace impedance also affects the interference between the boards,so the optimized PCB trace geometry is modeled from the signal line length,dielectric layer height,signal line width and signal line thickness.By studying the matching between the PCB trace impedance of the high-speed circuit,the impedance of the connector and the impedance of the interconnect line,the transmission quality deterioration caused by signal reflection is prevented.Three types of interconnected impedance control methods including a multilayer ground structure,a parallel ground structure,and a loosely coupled wiring structure are also employed to further suppress interference between high speed boards.Finally,multiple versions of the prototype were tested to verify the effectiveness of the interconnection anti-interference technology between the high-speed boards,and the overshoot caused by the inter-board interconnection could be reduced to within ±2.5%.Through the combination of simulation analysis and process experiment,the original high-speed circuit interconnection process system is supplemented,and a new and practical board-level electromagnetic protection process method is introduced to form a specification to solve the electromagnetic compatibility problem at the interconnection manufacturing level.