Pattern shaping for handset antennas

Traditional handset designs for personal communications have used simple antennas and it appears that little attempt has been made to shape the radiation pattern in a systematic way. Although diversity designs have been discussed, e.g. by Jensen and Rahmat-Samii (see IEEE Trans. Antennas and Propagation, vol.42, p.1106-1113, 1994), and Ogawa and Uwano (see IEEE Trans. Antennas and Propagation, vol.42, p.1342-1345, 1994), a clear analysis of what constitutes a “good” handset pattern has not yet been made. The authors discuss these questions, suggest a classification for the possible structures, and present some work on modelling and measurements of prototypes for the new generation of systems working around 1.8-2 GHz