Near-field of antennas and its implications for wireless communications

Traditionally near-field zone of an antenna is characterized based on the maximum dimension of the antenna. However this does not happen to be the case when the antenna is radiating over ground plane, where the height of the antenna above the ground does play a crucial role. The goal of this paper is to demonstrate the near-field behavior of antenna radiating over an imperfectly conducting ground. We first discuss the field variation with distance from the transmitter. Finally we make some observations regarding the variation of the field strength and channel capacity with the height of the transmitter and receiver.