Satcom at a crossroads

The need for more data communications in far-flung parts of the world is driving the Defense Department’s insatiable demand for satellite communications services. But with the Transformational Communications Satellite (TSAT) program potentially canceled, or at best delayed, it might be years before DOD can field a high-bandwidth communications satellite with the capabilities slotted for TSAT.

Yet there are other ways to get that capability in space. Many of the capabilities planed for the TSAT program — including  on board IP routing capability — are already in place or being tested by commercial satellite providers. And commercial providers say they can offer more capabilities over time — even directly supporting military applications through “hosted payloads” that ride aboard the satellites.

“Due to economic tough times, it's a lot cheaper for the government to buy commercial capacity for their needs than it is to launch satellites and do new programs,” said Daniel Longfield, an analyst at Frost and Sullivan who covers satellite communications.

The problem is that major commercial satellite vendors are already operating at near peak capacity, Longfield said. That has created problems for DOD in sustaining operations. In February, DOD officials contacted Intelsat General after the failure of another company's commercial satellite that was slotted to provide data communications, including the operation of Predator unmanned aerial vehicles over Iraq and Afghanistan. DOD and Intelsat declined to name the other company.

“Really, they were in a very bad way,” said Kay Sears, president of Intelsat General. “They didn't know where they were going to get the bandwidth to support ongoing operations as well as new UAVs.”

To provide the bandwidth needed, Intelsat reassigned customers from a Galaxy 26 satellite over North America and drifted its orbit to move the satellite over the Indian Ocean to provide the coverage DOD needed. Satellite drift is the process of using navigational engines on the satellite to gradually alter its geospatial orbit. In three weeks, Intelsat was able to move the satellite into position and give the Central Command continuity of service and "the capability to operate 40 simultaneous Predator missions. So they got a lot of capacity in a very short amount of time,” Sears said.

However, moving existing satellites isn’t a long-term strategy for meeting evolving needs, especially with the expanding demand for UAV support. “The amount of satellite bandwidth required to operate an unmanned aerial vehicle is huge,” Longfield said. “And as DOD transitions from Iraq to Afghanistan, they're going to be more reliant on those because it's more difficult to get aircraft over Afghanistan, so obviously they're going to want to use a lot more UAVs.”

To be able to support that command, control, communications, computers, intelligence, surveillance and reconnaissance demand — and applications such as communications on-the-go — DOD will need not only more satellites but also some of the new technologies slated for TSAT. One of those capabilities is satellite-based network traffic routing. Instead of a satellite acting purely as a bridge between a transmitting terminal and a network ground station, a satellite with a router could distribute traffic to its destination, substantially cutting down the length of the trip taken by data by eliminating multiple satellite hops. A hop is a satellite connection from one ground point to another relayed by the satellite.

Hughes Networking Systems’ Spaceway 3 satellite, a Boeing-built communications satellite launched Aug. 14, 2007, carried the routing capability being developed for TSAT. The router allows users of Spaceway’s satellite Internet service to communicate with one another directly through the satellite. In November 2008, the Defense Information Systems Agency signed a cooperative research and development agreement with Hughes to investigate development of applications for the Spaceway satellites. But Spaceway’s existing coverage is only over North America, making it ineffective for meeting one of the biggest demands for IP-based satellite communications.

Intelsat is performing a technology demonstration of satellite-based routing of network traffic with a satellite it plans to launch this fall. The technology, called IP Router In Space (IRIS), will be part of the payload on the Intelsat IS 14.

“We are demonstrating a capability that would have eventually been put on TSAT,” Sears said. Benefits of IRIS could include improvements in throughput and traffic management and a reduction in the size required for a satellite terminal, she said.

“The commercial satellite industry is more conservative,” Sears said. “We implement technologies incrementally, instead of all at once like [DOD tried to do with] TSAT. We make small prudent tech innovations that are incremental and lower risk, and we kind of evolve our fleet over time. So we are ready and willing to incorporate some of the TSAT capabilities into our spacecraft as those capabilities become evident, and we see that those things are the sort of things DOD would like us to implement.”