Multiuser Receiver Architectures for Space Modems
Abstract
In this article, we develop multiuser modem architectures suitable for augmentation of existing software-defined flight radios with important near-term enhancements to relay telecom services as well as support for missions requiring entry, descent, and landing (EDL). EDL support for missions like Mars Exploration Rover (MER), Phoenix, Mars Science Laboratory (MSL), and Mars 2020 obtains strong visibility within JPL and NASA headquarters. As part of an agency-wide commitment to support EDL, funding has been made available on past missions to prepare multiple Deep Space Network (DSN) ground station sites, non-DSN ground stations (Greenbank 100-m), and to prioritize in situ coverage from multiple orbiters. Multiuser operations open up new possibilities for simultaneous support of multiple surface landers that are in close proximity such that these surface elements simultaneously appear in the same coverage circle of a single relay orbiter. Simultaneous multiuser support is an important service type for many future surface mission paradigms. In this article, designs for field-programmable gate array (FPGA) implementation of multiuser modems are presented. A fixed-point model of the most promising architecture for space applications is presented as well as simulated performance results based on a fixed-point design that is suitable for FPGA implementation.
- Publication:
-
Interplanetary Network Progress Report
- Pub Date:
- August 2014
- Bibcode:
- 2014IPNPR.198A...1B