Analysis of DCS-1800 portable phones with microstrip antennas

Two different hand-held phones operating at 1.8 GHz are numerically analyzed, applying a finite-integration field calculation program. One phone contains a back-mounted microstrip double patch antenna (BMMDPA), the other, for comparison, a conventional monopole. Realistic models of the handset, the head and the hand are implemented to gain a detailed understanding of the antenna properties, as well as of the antenna-tissue interaction. For the BMMDPA, results of the reflection coefficient from experiments are also presented. Calculations reveal a much higher antenna efficiency for the BMMDPA, associated with a significant reduction of the absorbed total and peak power in the head.