A novel approach for characterization of multibeam communication payloads

Abstract

Communication payload architecture has changed from a conventional single broad beam to a large number of spot beam forms to meet the ever-increasing data rate demand. Owing to the large telecommunication requirements of the user, current generation satellites are equipped with a large number of transponders/beams. Due to the increased number of payload beams, performance evaluation and validation time increases during all stages of the satellite integration process. Also, satellite testing in thermal–vacuum (TVAC) conditions is hugely cost-intensive. Under such circumstances, the conventional test setup established for multibeam payload characterization presents limitations and increases overall measurement time. The paper proposes a novel switch matrix (SWM) based architecture for integrated multibeam payload characterization at payload input and output to significantly reduce effective uplink and downlink transmission line chains required for RF characterization without compromising overall measurement accuracy. We have developed a Telecommand and Telemetry (TCTM) simulator system for closed-loop automated switching of switches in SWM to reduce human intervention and ensure safety aspects of payload. We present the SWM approach for two classes of high throughput satellites (HTS), namely, symmetrical and asymmetrical architectures. The results show that the proposed approach is robust and advantageous in overall RF performance, reduction in the number of interfaces, electromagnetic interference and electromagnetic susceptibility (EMI/EMC) considerations, electrical integrity, and ground test setup complexity compared with conventional characterization philosophy.