Design and Experiments of Radial Line Helical Phased Array with Antenna Elements Rotated by Motors

Radial line planar array with probe-fed helical antennas, which was proposed by Nakano et al. [1], is a high gain antenna with high efficiency, low profile, and light weight. Recently, the demand for beam scanning antennas or phased array antennas has been increasing with the rapid growth of the wireless communication systems. In conventional radial line planar arrays with probe-fed circular-polarized antennas, only the beam-tilting in a fixed direction was accomplished by manually rotating antenna elements [1]. In this paper, a helical phased array using electromechanically-controlled antenna elements, which are rotated by micro-motors, fed from a radial line is proposed to achieve the dynamic and electrically-controlled two-dimensional beam-scanning.