LAUSR

In this paper, compact direction finding systems using a scatterer of a high dielectric constant in between adjacent closely spaced electrically small antennas are examined. By adding a high-permittivity scatterer, the directional sensitivity can be enhanced. However, due to limited physical dimension, an electrically small antenna has highly reactive impedance. To enhance the received power level, a matching network is included. The highest directional sensitivity satisfying a given power constraint is compared for with and without scatterer cases. In addition, widely used matching approaches such as multiport-conjugate matching (MCM), self-conjugate matching (SCM), and eigenmode decoupling matching are investigated to increase the received power. The impact of these matching networks on the directional sensitivity is studied. The power and the directional-sensitivity bandwidth after matching are also analyzed. Finally, the two-monopole and a high-permittivity scatterer system with SCM and MCM circuits is fabricated and tested.