Performance Analysis of Different Loaded and Unloaded Wire Antennas as EMI Sensors

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 is required to evaluate the field strength at a certain distance from it using the sensor. The most common performance descriptor of a sensor is its antenna factor. Here, the method of moments with pulse basis function and point-matching technique has been used to evaluate the current distribution on the antenna surface, and hence, the antenna factor of different wire antennas. The same theory for unloaded antennas has been extended for different loaded-wire antennas. The loaded antennas in transmitting mode are widely used for low-frequency communication. However, while using these antennas as EMI sensors, the extra loading is likely to introduce the reception of cross-polarised component of incident electric field. This paper highlights the results of the initial investigation on the performance of these loaded antennas as EMI sensors in terms of the antenna factor for the desired and cross-polarised component of incident electric field.