Advanced EHF Beam Forming
Network Firmware

Client: EMS Technologies
See the EMS press release.

Advanced EHF is a set of US military communications satellites. They are the next generation of the Milstar constellation.

The Beam Forming Network: the BFN provides "anti-jamming" capability used to counter jamming signals directed at the satellite from the ground.

The spaceflight firmware for Advanced EHF responds to customer commands, produces lookup tables used for commanding microwave phase-amplitude controllers, processes uploaded information, and performs maintenance tasks. The firmware runs on a Dallas DS80C320-compatible 8051 macro within a custom, space-qualified gate array. Most of the firmware is written in C, with some assembly.

Over thirteen months, Pink Shirt Software defined requirements, architecture, detailed design and hardware interfaces, performed all development and supervised testing, and documented the above in a Firmware Specification. The Specification is used extensively by client personnel, and was delivered to their customer. Code included startup sequence for the BFN's electronic and microwave systems, memory tests, use of external and timer interrupts, command handling, maintenance tasks, population of tables used by the gate array, and updating of tables in response to temperature changes. A suite of test commands provided microwave engineers with specialized test capability. Development tools included the Tasking 8051-C compiler and simulator, Nohau EMUL51-PC In-Circuit Emulator (ICE), custom hardware prototype of the BFN's electronics, and various lab equipment. Working closely with electronics, microwave, and test engineers to ensure that the firmware and specifications met the needs of the project.

This system is quite complex, with beam-forming outputs to microwave components varying with more than ten different system variables.