EMI - Electromagnetic Interference

Unwanted electromagnetic radiation that causes potential interference to other items of electronics equipment in close proximity.

There are many ways in which electromagnetic interference can be carried from one item of equipment to another. It is important to understand which devices are emitting radiation before a system is designed to avoid potential problems further down the line.

There are different forms of interference as follows:

  • Continuous interference: Often from a radio signal or alternating current
  • Impulse interference: Resulting from a short impulse such as lightening, a switched circuit or electrostatic discharge.

Apart from understanding the form of the interference, it is also necessary to know how the interference is travelling from the transmitting device to the receiving device. Unfortunately this is not always easy but as aforementioned, understanding of the equipments end user and environment are key to designing the best system from the start of the project.