Contractor selection near for navy satellites.

• Author: Peck, Michael

The Navy is nearly ready to select a contractor for the mobile user objective system (MUOS), a constellation of ultra high frequency communications satellites designed to replace the current UFO (UHF Follow On) system.

The multibillion dollar contract will be awarded in late June to either Lockheed Martin or Raytheon.

Slated for launch in 2009 and full operational capability in 2013, MUOS will transmit at almost 40 megabits per second versus the two to five megabits of UFO, according to program manager Robert Tarleton, with the Navy's Space and Naval Warfare Systems Command.

MUOS and UFO are narrowband--less than 64 kilobits per second communications satellites that relay tactical UHF voice and low speed data communications, which have become increasingly crowded.

"Studies on UFO that were done a couple of years ago say that the UHF is 250 percent oversubscribed," said Tarleton. Operations in Iraq and Afghanistan have only worsened the bandwidth crunch.

Just as vital as MUOS's increased bandwidth is its ability to allow troops to communicate on the move. "UFO has been described as communications on the pod. If you're moving, you have to stop. You need directional antennae. With MUOS, we're expected to have the capability to get to a unidirectional antenna with the solder in the foxhole."

MUOS and UFO are part of a broad array of communications satellites operating all along the bandwidth spectrum. High-capacity satellites such as the Wideband Gapfiller handle megabyte-rich data streams such as photos transmitted by the soaring numbers of unmanned reconnaissance aircraft. Protected satellites such as the upcoming advanced extremely high frequency spacecraft have links hardened against jamming and nuclear effects.

Narrowband satellites lack the bandwidth to handle large amounts of data, and while their signals are encrypted, they are not proofed against jamming. "UHF does not have that requirement," said Tarleton. "Our only requirement is anti-jam command links so we don't lose the satellites."

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