Europa Lander radio crossband relay hardware prototype

Abstract

Existing Frontier Radio hardware was modified to create a low Size, Weight, and Power (SWaP) Crossband Radio prototype to support testing the Lander relay capability requirement for the Europa Clipper Radio. The crossband design consists of four slices: Power Converter Unit (PCU), Digital Signal Processor (DSP), X-band Exciter, and X-band Receiver. Although software modifications were needed, firmware was not changed. Hardware modifications required to achieve a crossband design were limited to the exciter and receiver slices with the DSP and PCU slices unchanged. The crossband radio receiver capability covers the entire Deep Space Network (DSN) X-band return link frequency allocations for deep space (8400 to 8450 MHz) and the exciter supports the entire DSN X-band forward link frequency allocations for deep space (7145 to 7190 MHz). Component changes and modifications included installing alternate Voltage Controlled Oscillators (VCOs) with corresponding bias voltage adjustments, amplifier and multiplier retunes via passive component changes, surface mount and resistive attenuator adjustments, modifications of filtering, and additional external bias-T and Low Noise Amplifier (LNA) hardware. All of the frequency retunes were accomplished with no change to the physical circuit artwork, which demonstrates the flexibility and robustness of the Frontier Radio design. Bench tests were conducted for both the exciter and receiver at the new crossband frequencies. The Crossband Radio prototype was connected to a typical non-crossbanded engineering model Frontier Radio in a radio test bed to conduct relay communication testing. The channel between the radios was simulated using variable and fixed attenuators as well as a channel simulator. Flight software was created and loaded onto the radio, which is run in the Microprocessor without Interlocked Pipeline Stages (MIPS) core of the field-programmable gate array (FGPA). Results from relay communications testing and use case scenarios are presented here.