Performance Analysis of Different Loaded and UnloadedWire Antennas as EMI Sensors

Abstract

This paper presents with the performance of different loaded (e.g. inverted L, T, I and C-shaped antennas) and unloaded wire antennas as electromagnetic interference (EMI)sensors. To determine electromagnetic radiation from an electronic component, it isrequired to evaluate the field strength at a certain distance from it using the sensor. Themost common performance descriptor of a sensor is its antenna factor. Here, the methodof moments with pulse basis function and point-matching technique has been used to evaluatethe current distribution on the antenna surface, and hence, the antenna factor of different wireantennas.  The same theory for unloaded antennas has been extended for different loaded-wireantennas. The loaded antennas in transmitting mode are widely used for low-frequencycommunication. However, while using these antennas as EMI sensors, the extra loading is likelyto introduce the reception of cross-polarised component of incident electric field. This paperhighlights the results of the initial investigation on the performance of these loaded antennasas EMI sensors in terms of the antenna factor for the desired and cross-polarised componentof incident electric field