The Universal Space Transponder: A Next Generation Software Defined Radio

The Universal Space Transponder (UST) is a next
generation transponder developed at the Jet Propulsion
Laboratory to meet a large variety of telecom, navigation, and
radio science needs for future deep-space and near-Earth
missions. This paper details the UST software defined radio
design and describes how the combination of a modular
hardware architecture and in-flight reprogrammability enables
a new level of flexibility and expandability for a space
transponder. The UST uses common power and digital
processing assemblies that can be integrated with a variety of
RF modules and is capable of simultaneous, multiband
operations with data rates up to 37.5 Mbps RX and 300 Mbps
TX. This allows a single radio to support all the direct-to-Earth
and relay communication requirements for even complex
mission scenarios, reducing the total cost, mass, and power. The
discussion includes a description of the current UST engineering
models that have been built and tested, as well as details about
the next generation capabilities supported by UST, including
advanced link coding and modulation, radiometric techniques,
and in-radio protocol handling. Details are also presented on RF
modules and digital processing in development for radio science
and astronomy purposes, including a bistatic radar receiver and
broadband planetary emissions receiver. These will
demonstrate the ability to integrate low-cost science instruments
into the UST architecture, further expanding the versatility of
the UST.