Ground system adds more bandwidth to cluttered airspace

  • Published
  • By Kenji Thuloweit
  • 95th Air Base Wing Public Affairs
EDWARDS AIR FORCE BASE, Calif. (AFNS) --  The installation of a first-of-its-kind aeronautical telemetry ground system at the U.S. Air Force Test Pilot School here is improving aircraft communication in airspace already jumbled by frequencies from cell phones and satellite television.  This technology expands communications capability between aircraft and ground-based people and equipment.

"Due to technological advances and the increase in civilian use of various frequencies, some of which happen to be the same frequencies we use, there has been a need to expand our range of frequencies for flight testing," said John Ward, the Test Management Group's program manager for Telemetry Systems Integration and Support, or TSIS.

Telemetry is a technology that allows remote measurement and reporting of data from an aircraft to engineers on the ground to assess the aircraft's performance.

Engineers working on the TSIS program, in collaboration with Test Pilot School representatives, have installed the new aeronautical telemetry ground system, which is capable of acquiring airborne telemetry data in the L-band, S-band and now C-band frequency ranges. The system replaces an older ground telemetry system, which was capable of receiving telemetry only in the L and S ranges.

"Air-to-ground telemetry has always been conducted in the 1435-1525 megahertz (L-band) and 2200-2395 megahertz (S-band) frequency ranges," Mr. Ward said. "However, as we test aircraft with greater technology advancements, more telemetry bandwidth use is inevitable and this new tri-band telemetry capability will expand the range of available telemetry frequencies into the 4 gigahertz and 5 gigahertz ranges (C-band)."

The additional frequencies added will benefit both the surrounding community and the different units on base by relaxing the encroachment of frequencies used by civilians and other units.

"You may have emergency response companies and cell phone companies all desiring to use more and more frequencies, and that could cause congestion in the frequencies we use here for flight tests," Mr. Ward said. "Part of our goal is to help accommodate the increase by adding more frequencies that will allow us to conduct flight tests while at the same time allowing civilians to continue using our frequencies."

Mr. Ward says this new tri-band telemetry capability with the C-band receiver is likely the first of its kind in the world. The C-band installation occurred much earlier than expected because of a unique collaboration among TSIS program engineers, TPS officials, 412th Test Wing representatives and contracting office specialists. The flexibility of TSP schedulers, the small number of aircraft to equip and the working relationship with the different offices were big factors in setting up the system ahead of schedule.

According to TSP officials, the new C-band will help the school a great deal because, with numerous test squadrons at Edwards, the fight for frequencies can be challenging.

"Being the first to get ground-level C-band is a plus because we're always competing for bandwidth with the rest of the base and we have one of the lowest priorities," said Steve Connor, TPS lead telemetry and data acquisition engineer. "To be able to go full C-band is going to work out perfectly for TPS."

Some acceptance testing still remains for the TPS ground systems. Early testing has been very encouraging and full initial operating capability is expected by July. The TSIS program is a five-year improvement and modernization program to upgrade the entire Air Force Flight Test Center ground and airborne telemetry capability.