Receiving Antenna Realized Gain Understood by the Poynting Streamline Method

Antenna realized gain is generally defined and used to analyze transmitting antennas, but rarely for receiving antennas. In this paper, we use a direct way to model and understand the receiving antennas. The flow of electromagnetic energy around a receiving antenna is modeled by generating streamlines of the Poynting vectors. The realized gain can be described by a two-dimensional geometry, where the streamlines within this region are absorbed by the antenna load. Compared to the traditional equivalent circuit, this image provides a closer physical way to explain and understand the realized gain for the receiving antennas.