A digitally beam-steerable antenna array system for positioning-based tracking applications

In line-of-sight airborne applications, deployment of a steerable antenna array with higher directivity and gain makes sense for reducing ground-station complexity and cost, while still maintaining a reasonable link budget. This paper reports on the design, development, and successful testing of a digitally beam-steerable phased-array antenna integrated as a complete system, comprising the antenna, hosting platform, ground station, and aircraft-based emulator to facilitate convenient aircraft-based testing of the antenna array and ground-air space communication link. Based on the measurements, the 4 × 4 element prototype tested reduced the error rate by a factor of seven in comparison with a 4 × 4 array without steering. For the same link quality, the power required was 12 dB lower than in the case of a single-element antenna. With only minor modifications, the concept can even be used in a Low Earth Orbit (LEO) satellite environment.