FPGA Based Control for Powering Advanced New Generation Flexible Satellite Payloads

Abstract

High speed Digital control systems are finding wide acceptance in recent years for space systems; especially in the power systems and communication systems applications. This made possible due to the availability of robust radiation hardened Field Programmable Gate Array (FPGA) devices with high speed processing capability. Advanced digital control techniques using FPGA devices can be implemented in satellite Radio Frequency (RF) power Amplifiers like Solid State Power Amplifier (SSPA)s and Travelling Wave Tube Amplifier(TWTA)s which make the amplifiers not only “dynamic & flexible" but help in mitigating onboard anomalies and nuisance associated with Electro-Magnetic Interface (EMI) also. This thesis investigates the study and implementation of digital control on SSPAs required for Navigation satellites or Advanced Flexible communication payloads using an FPGA. This work will be confined to the design and implementation of an FPGA based digital control circuit in an Electronic Power Conditioner (EPC), which is powering SSPA. By doing so, a conventional SSPA can be enhanced to a “Flexible SSPA". The implementation of this digital techniques in EPC in place of conventional analog techniques, can lead to additional advantages like Dynamic operation viz. Adjust automatically onboard for optimum performance and Flexibility in operation like reprogrammable / reconfigurable the amplifier by tele-command for setting the output power level, gain, linearity, bandwidth, RF envelope tracking etc which are inevitable to equip the power amplifier for meeting the challenges posed by new generation Flexible Satellite payload architectures. The concepts demonstrated under this thesis will be implemented in realization of Flexible SSPA of new generation Communication or Navigation satellite payloads.