Reconfigurable Phased Array Antenna Consisting of High-Gain High-Tilt Circularly Polarized Four-Arm Curl Elements for Near Horizon Scanning Satellite Applications

摘要

A 2 × 2 phased array consisting of beam reconfigurable four-arm right-handed circularly polarized (RHCP) curl unit elements antenna is presented. This array is designed at test frequency of 5.2 GHz and can undertake a high-gain near-the-horizon scanning with low grating lobes. Each curl antenna element has four ports and can provide four RHCP tilted-beams (θ= 48°) with a gain of 8.3 dBic. By switching the feeding ports, the curl element can reconfigure/switch these unit element beams in four different quadrants in space. The array exploits these high-gain high-tilt switchable beams for generating an extremely wide scanning range from −80° ≤θ ≤ +80°. For the 2 × 2 array, in this range, the beam has a maximum gain of 12.4 dBic atθ= 40°. More importantly, the array provides RHCP beams with a gain of 10.5 dBic at near-the-horizon angles ofθ ≍ 70° and provides a lower gain of 6.5 dBic in the zenith direction. This has promising applications in communications on the move using a flat panel antenna to geosynchronous orbit satellites. Here, when operating at high latitudes require high-gain at near-the-horizon angles.