Study On The Key Technologies Of Simulation For Electrostatic Dsicharge Interference To Receiver System

Along with the fast development of the electronic industry, increasing application of the electronic equipment and component are discovered in the information industry and daily life, leading to the more severe electromagnetic pollution, so the request for the electromagnetic compatibility is enhanced. The working performance of receiver system which functions as the subsystem of the telecommunication determines the communication signal quality. However the nature features of the receiver make it easier to be influenced by the electromagnetic interference. As an important electromagnetic hazard source, electrostatic discharge interference can cause the interrupt of the communication link; therefore the protection from the electrostatic discharge has become a significant part in the electromagnetic compatibility immunity, so has the simulation about the electrostatic discharge.Complexity of the receiver system and electronic equipment structure inside has been enhanced compared to the past as the shielding enclosure with the slots or seams, cables, circuit components and mechanical components included. The difference of the location where electrostatic discharge occurs will produce the different disturbed performance. The paper first introduces the principle, harmfulness, the circuit model and the radiation model of the electrostatic discharge, subsequently provides the circuit model and the full-wave model of the human-metal discharge for the latter simulation. Also the interference coupling paths to the device is elaborated; the simulation results for different circumstances of the discharge to the equipment are analyzed. The main working contents in this paper are listed as follows:(1) The coupling effect of the electromagnetic interference to the slots on the shielding enclosure in receiver system is studied. Electrostatic discharge on the enclosure is simulated to observe the coupling filed inside. Also the position of the tip for discharge is studied to ensure the sensitive zone of the shielding box. According to the results of simulation, corresponding protection method is established to enhance the electrostatic discharge immunity.(2) Towards connection cables in receiver system, transfer impedance of the coaxial cable by tubular shield and by braid shield is calculated respectively as well as the disturbing currents and voltages are simulated and compared by contact discharge on the shielding screen. In terms of different grounding connection method, the identical shielding cable's response to the disturbance is simulated and developed, followed by the improved measures for grounding method to reduce the disturbance.(3) For the case that coaxial cable's screen is grounded by connecting to the shielding enclosure of the equipment, the interference noise derived by electrostatic discharge on the box will most likely diffuse along the cable and impact the subsequent circuit or system. So the concerned simulation and study are carried out aimed at this circumstance that proper connection method can be proved.(4) Finally, the receiver's front end in the communication system on Shadow UAV is taken as an example to examine the work performance when facing the electrostatic disturbance. The direct application on the circuit board is estimated and corresponding solutions are proposed such as using varistor termination. Also, the noise on the RF circuit reproduced by the electrostatic discharge is compared to the system's noise floor to prove the working property of the system when accidental shock occurs.