antennefaktorer

Antennefaktorer, often translated as antenna factors, are a concept primarily used in the context of electromagnetic compatibility (EMC) testing and measurement. They serve to relate the measured voltage or current at a receiver's input to the electric or magnetic field strength at the antenna's location. Essentially, antenna factors provide a conversion factor that allows engineers to translate measured electrical quantities into physical field strengths, which are critical for determining if a device complies with EMC regulations.

These factors are dependent on several parameters, including the frequency of the electromagnetic wave, the physical characteristics of the antenna itself (such as its size, shape, and length relative to the wavelength), and the polarization of the incident field. Different antenna types, like dipoles, monopoles, or log-periodic antennas, will have distinct antenna factors at various frequencies. For instance, a specific antenna might have a higher antenna factor at a particular frequency, indicating that a smaller electric field will induce a larger voltage at the receiver for that frequency.

Antenna factors are typically provided by antenna manufacturers in calibration certificates or datasheets. They are often expressed in units of inverse meters (m⁻¹) or inverse decimeters (dm⁻¹). The calculation involves comparing the measured response of the antenna to a known and precisely controlled electromagnetic field. This calibration process ensures the accuracy of EMC measurements, enabling the correct assessment of radiated emissions and susceptibility of electronic devices. Without accurate antenna factors, it would be difficult to reliably determine compliance with international EMC standards.