Title: A Ka-band to baseband RF Testbed for the SWOT system
Author: Paul Siqueira
Organization: University of Massachusetts
Co-Authors: Kan Fu, Vishwas Vijayendra, Russel Tessier, Brandon Heavey, Dani Esteban-Fernandez, Michael Nakashima,

As part of the effort for the design and testing of a Ka-band two-channel interferometric receiver for the SWOT mission, the University of Massachusetts, with input from the Jet Propulsion Laboratory, has constructed a baseband to Ka-band (35 GHz) and Ka-band to baseband testbed system, which is capable of monitoring the performance of key RF subsystem components as a function of temperature and other operating conditions. Primary to this development has been the construction of a direct, Ka-band to L-band downconverter, followed by two channels of direct sampling at L-band (3 GSamp/sec) which is capable of simultaneously recording low data rate telemetry into an FPGA (Xilinx-4) architecture, for the purpose of signal compensation for measured environmental changes. In this talk, we present this receiver system and its function in context of the larger testbed setup. Although the testbed is still under development, its basic functionality has become very useful for a number of different system tests.