20 Gigahertz (GHz) Radiation Hardened Solid State Power Amplifier (SSPA) for Satellite Communications (SATCOM) Downlinks

ABSTRACT: To support high data rate battle field communications, future military satellite communication systems will be required to provide higher signal capacities by employing complex modulation schemes in closely spaced channels. To meet this requirement, a new generation of Solid State Power Amplifiers will be needed. This proposal is aimed at the development of radiation hardened, ultra linear, high efficiency, solid state power amplifiers operating in 20.2 21.2 GHz with key performance specifications: Pout>2W, PAE>35%, linear gain>23 dB, ACPR<-40dBc, for transmission of high data rate QPSK and 64 QAM modulation. To achieve high efficiency, State-of-the-art pHEMT or emerging wide bandgap GaN HEMT MMIC operated in Class E switching mode in push-pull configuration will be developed. To achieve high linearity without sacrificing efficiency, digital pre-distortion linearizer with envelope tracking and drain-gate modulation will be used. BENEFIT: The K-band radiation hardened, ultra linear, high efficient SSPA with Power output>2W, PAE>35%, bandwidth>2GHz, and ACPR<-40dBc do be developed will provide enabling technology for the development of high data rate, closely spaced multichannel high volume communication systems. The devices can be used not only for space, aircraft, UAV, and ground defense applications, but also for various commercial applications. By employing power combining techniques, the technology can be extended to higher power output applications. The technology can also be applied to the development of SSPAs for other frequency bands.