Estimation of high-frequency current distribution on an antenna

A simple approximation equation led from Ampere's law has been applied, for the first time known to the authors, to estimate accurately the high-frequency current distribution on a dipole antenna located near a human model. A comparison of the estimated current distribution on the antenna with a theoretically rigorous one shows that the estimation error of this method is as small as within 2% around an antenna feed point at a frequency of 900 MHz. By using this method, a feed point current has been clarified to increase by about 30% compared to the case in the absence of a human model, and the absorbed power at the model has been accurately estimated. All these results show that this current estimation method is useful in the antenna design for hand-held portable phones.