A dual six-port with two-angle resolution and compact size for mobile terminals

A compact, low frequency wide-band, dual-angle resolution dual six-port design for direction finding (DF) systems within mobile terminals is proposed. This system covers the frequency band from 1.68 GHz to 2.25 GHz with a minimum bandwidth of 570 MHz. This relatively low frequency operation is unique to this design for DF, as most of the available design covers high frequency bands above 2 GHz. In addition, a major contribution of this optimized design is 40% reduction in the total area compared with the closest design. Moreover, the proposed system is distinctive as it is capable of finding the direction in both elevation and azimuth planes. This six-port design is realized on a dielectric substrate area of 65 × 65 × 1.28 mm³.