Electromagnetic Interference Emitted from Electronic Devices

Measuring the level of electromagnetic interference emitted by electronic devices is an important part of the process of production and development of these devices. Today, these measurements are performed by specialized laboratories that are equipped with an anechoic or semi-anechoic chamber. For manufacturers of electronic devices, it would be beneficial if a Gigahertz Transversal Electromagnetic (GTEM) cell would be possible to use for measurements of emitted electromagnetic interference. A GTEM cell may be purchased at a fraction of price of an anechoic or semi-anechoic chamber, so manufacturers would be able to perform these measurements themselves during the development of the device. In this paper is published the measured levels of electromagnetic interference radiated by the basic set of intrusion and hold-up alarm system in the semi-anechoic chamber and GTEM cell. The basic difference in the measured levels of EMI is based on the type of the measured electromagnetic interference. Electromagnetic interference, which is located in the far-field of an electronic device, is recorded in the semi-anechoic chamber while the interference in a near-field is recorded in the GTEM cell.