A consideration on Ka-band active phased array antenna for Gigabit Satellite

Abstract

High data rate satellite communication system called Gigabit Satellite, which can achieve the transmission rate of more than 1.2 Gbps, is planned to launch as an experimental satellite in Japan and the basic consideration for this program has been proceeded. In this system, a Kaband scanning spot beam antenna (SSBA) with multiple beams is required. Therefore, an active phased array antenna (APAA) which can steer the multiple beam electrically is considered and one can realize high EIRP and G/T performance for multiple international service areas. An APAA realizes flexible multiple beam forming by using a beam forming network (BFN) with phase shifter. Since the performance such as antenna gain and beam scanning properties are restricted by the antenna configuration, we have been studying the feasibility of the Ka-band APAA. APAA has been developed mainly for radar systems for many years. CRL and MELCO have been developed the S-band APAA for intersatellite communication of the engineering test satellite launched in 1994. As the Gigabit satellite, CRL and MELCO are investigating and developing the direct radiating APAA for communication satellites which can operate under wide frequency band in Ka-band. This paper describes the preliminary study results of the Ka-band APAA for Gigabit Satellite.