A CCSDS 131.2-B compliant telemetry downlink hardware-software emulation platform for next-generation Earth observation missions

Abstract

During the last few years, the throughput requirements of payload data telemetry (PDT) systems for Earth observation (EO) satellites have increased considerably. The CCSDS 131.2-B standard, issued in 2012, has already proven to be a sound solution for high-rate telemetry applications, especially when link adaptation techniques are required to cope with variable channel conditions. In particular, this standard and the adaptive coding and modulation (ACM) technique that it inherently supports could be adopted in the forthcoming Copernicus missions, which pose new challenges to PDT regarding throughput requirements. Since systems with comparable performance have never been deployed, a comprehensive test environment is needed to carry out a thorough validation phase.This paper presents a CCSDS 131.2-B ACM testbed that implements an end-to-end communication system for telemetry data downlink from a low Earth orbit (LEO) satellite, supporting symbol rates up to 500 MBaud. Including the emulation of a Sun-synchronous orbit (SSO) and the main channel impairments encountered in a Ka-band transmission, this testbed aims to accurately model the data flow of future EO missions. Furthermore, by allowing a comprehensive evaluation of the link performance, it turns out to be an effective tool for supporting system design and fine tuning of link adaptation strategies.