**3.3 Electromagnetic compatibility technology**

In the electronic circuit system, when there is a high-frequency circuit, the circuit will radiate electromagnetic waves to the outside, or some parts of the system use components that can radiate electromagnetic waves. These radiated electromagnetic waves will interfere with other nearby equipment and will be coupled to the circuit through wires and various connectors, causing interference to the signal in the circuit. There are also many elements with antenna functions in the circuit system, such as cables, printed circuit boards, and some mechanical structures. These elements can be coupled to other lines in the form of electric and magnetic fields, causing interference to the system. Electromagnetic compatibility (EMC) of equipment or system refers to the ability of equipment or system to work normally in an electromagnetic environment without causing unbearable electromagnetic interference to any other thing in the environment.

The project team has analyzed and studied the electromagnetic compatibility technology of the C-tube torsion pendulum micro-thrust/micro-impulse measuring device and processed the line shielding, grounding, lapping technology, and signal filtering technology for the system according to the actual situation, and finally carried out a comparative study of the influence of the electromagnetic compatibility technical measures on the measured signal of the system. The research results show that these processes reduce noise and improve the signal-to-noise ratio to a certain extent, but at the same time, it is also concluded that electromagnetic compatibility technology is not perfect, and it is difficult to completely eliminate noise and obtain clean measured signals by using electromagnetic compatibility technology alone. It is also necessary to filter the signal data by software, and the combination of the two can obtain more ideal signal data.
