The growing use of unmanned aerial vehicles (UAVs), like Predator and Global Hawk aircraft, is making military communications satellite bandwidth a vital part of national military infrastructure.

The remote piloting of UAVs, sometimes from thousands of miles away, and employment of UAV-carried sensors and weapons, make satcom bandwidth as vital for these unmanned aircraft operations as the fuel that powers their engines.

The U.S. government is responding to the fast-growing need for more bandwidth by retooling its entire military satcom fleet, leasing commercial services, and procuring an existing commercial spacecraft design to rapidly provide extra bandwidth for secret operations.

The introduction of even faster and more stealthy unmanned combat air vehicles (UCAVs), soon capable of aircraft carrier launch and carrying more diverse weapons, will also increase the need for greater bandwidth. This will be especially so when future strike packages require formations of multiple drones.

An often cited cliché has the president of the United States asking “where is the nearest aircraft carrier” whenever there is an unfolding military crisis.

Today’s commander in the field is more likely to ask, “How much bandwidth is available?” Too often the answer has been, “Not enough bandwidth to fully exploit the UAV fleet.”

That UAV bandwidth problem, however, is going to be much more effectively addressed by new military satellite systems. Those systems include:

•Wideband Global Satcom (WGS) system: The WGS satellites are becoming the key spacecraft for command of UAVs. The WGS program cost for the six satellites is about $2 billion. Each individual WGS has more bandwidth than the entire Air Force Defense Satellite Communications (DSCS) constellation in use since the 1980s.

Upon its launch into geosynchronous orbit in 2007, the first WGS vehicle became the Pentagon’s highest-capacity communications satellite. Two additional WGS satellites were launched in 2009, while satellites 4, 5, and 6 are anticipated for launch in 2011, 2012, and 2013, respectively. Both the Delta IV and Atlas V rockets are being used to launch the constellation.

WGS has 4.75 GHz of instantaneous switchable bandwidth, thus each WGS can supply more than 10 times the capacity of a DSCS III spacecraft. Each WGS is able to downlink 2.4 Gbps of data to tactical users. The new wideband constellation is also taking over the Ka-band service provided by the Global Broadcast Service (GBS) a high data- rate one-way link piggybacked onto several Ultra High Frequency UFO satellites launched in the 1990s. The WGS Ka system is used to ship key UAV-gathered intelligence imagery to hundreds of 18-inch diameter antennas that can be carried in the rucksack of any soldier or Marine.

•Advanced Extremely High Frequency (AEHF) constellation: The $12.4 billion cost of the four-satellite constellation illustrates the complexity and capability of these U.S. Air Force satellites to provide highly secure, encrypted communications to the National Command Authority and many other military users like UAV operators. The satellites will combine the capabilities of the Milstar and DSCS constellation. UAV data will be routed by special Advanced Beyond-Line-of-Sight Terminals developed for the AEHF program. Built by Lockheed Martin and Northrop Grumman, the first AEHF spacecraft is set for launch from Cape Canaveral by late summer 2010. Each satellite will be able to crosslink with its neighbor AEHF satellites. They will provide 10 to 12 times the overall communications capability and a data rate six times higher than the 1990s-era Milstar II constellation that the AEHF program will replace.

•Mobile User Objective System (MUOS): Managed by the Navy, the MUOS program was originally to be operational in 2010, but will be delayed until at least September 2011, when the first Lockheed Martin satellite is to be launched. The program’s total cost is estimated at $6 billion for 10 spacecraft across the 20-year life of the program until 2030. The spacecraft will unfold 16-foot diameter and 50-foot diameter antennas developed by Harris Corp. It also will carry a Lockheed Martin-built wideband code division multiple access payload that will provide a 16-fold increase over legacy UHF satellite capability. These will support new mobile satellite terminals that are under development within the Joint Tactical Radio System. These will support UAV operations.

•The PAN Secret satcom: An Atlas V rocket launched from Cape Canaveral in September 2009 carried a Lockheed Martin A2100 communications satellite into geosynchronous orbit that was procured on an emergency fast turnaround basis for a defense or intelligence agency that remains classified. The mission possibly involves the CIA as well as badly needed increases in UAV-related bandwidth related to CIA-led UAV strikes against terrorist leaders. Spacecraft characteristics point to a UHF relay mission for the spacecraft, likely related to providing stopgap service until the delayed MUOS spacecraft enter operation.

The satellite is designated PAN, an acronym that remains classified. A clue is that in aircraft and maritime operations a “Pan, Pan” radio call is used as a distress call indicating that a state of urgency exists that requires immediate attention and assistance. The PAN satellite was procured and developed in record time and the PAN designation could be signifying the urgency of getting this satcom relay bandwidth aloft to support UAV and other users.

During the first Persian Gulf War in 1990-1991, there were less than two dozen UAVs in theater. But now there are thousands of U.S. and NATO drones deployed in Iraq, Afghanistan, and over Pakistan. The largest number of these is highly portable man-launched “Tier 1” UAVs like the Raven built by AeroVironment and the Lockheed Martin Desert Hawk. Similar to large radio-controlled model airplanes, these Tier I UAVs enable individual Army and Marine patrols to scout nearby buildings and terrain that could conceal enemy positions. Such Tier I UAVs normally carry a single television camera and operate using short-range FM links. Their data rates are low enough to limit any significant bandwidth challenges.

Greater piloting and sensor link challenges are posed by Tier II aircraft like the Scan Eagle, Shadow, or Sentry that can operate up to several miles away from a control station, as long as the operator can remain within the UAV’s line of site to the horizon. New military satcom capabilities will begin to expand the range of these medium-size drones. This class of UAV can weigh 30 pounds and carry more sensor capability, including infrared and imaging radar, to support the tactical needs of larger units with tanks or other vehicles.

“The general perception of UAVs tends to be driven by news articles featuring larger aircraft such as the Predator that are flown by pilots in climate-controlled rooms half-way around the world, and whose intelligence output travels over Ku-band satcom links,” wrote Steve Gardner, general manager of Enerdyne Technologies, Inc., in an essay carried in Milsat Magazine. The company, based in El Cajon, Calif., is a subsidiary of ViaSat Inc. and develops digital television and data links for UAVs as well as manned systems.

“Those links allow viewing of data in real-time by U.S.-based mission commands, including the Pentagon and Creech AFB, at Indian Springs, Nev., the home base for both Predators and Reapers. The reality, however, is the role of the lion’s share of UAVs is to provide data to soldiers within 50 miles of the aircraft using line-of-sight air-to-ground links,” Gardner wrote.

“Today these links are predominantly analog FM links for standard definition video, but a change to sophisticated digital links is under way, driven by a range of factors. Tomorrow’s needs [including satcom links] include security, improved range, efficient use of spectrum, and support for a variety of complex sensors such as high definition video, laser designators, imaging radar and ground moving target indicators, and multi-spectral imagers,” he wrote.

It is with the larger Tier III UAVs like Predator and Global Hawk where added bandwidth will enable more simultaneous operations with multiple UAVs.

This is because Tier III UAVs require high data-rate command and control links for their pilots and carry multiple sensors, including sophisticated image processing payloads as well as weapons like Hellfire missiles. These aircraft include the small Predator and Reaper used to strike individual terrorists in Iraq, Afghanistan, and Pakistan and the large Global Hawk that can perform missions comparable to the U-2 reconnaissance aircraft.

The Air Force said there are currently 147 Predators in its inventory, with 185 the force objective. The service has only 48 MQ-9 Reapers, larger and more powerful than the Predator, which are armed with up to 3,000 pounds of bombs and Hellfire missiles. The DoD wants to greatly increase the Reaper force to 374, a major step toward an unmanned U.S. strike force that would make intensive use of satellite bandwidth only now being launched with the upgraded satcom fleet.

The RQ-4 Global Hawk is the most advanced UAV. There are only 17 Global Hawks currently, but the services want to increase that to 77, the Air Force said. The Army is also involved in extensive UAV operations.

The Predator and its cousins are controlled remotely by a two- or three-person team: a pilot and one or two sensor operators. Most of the CIA’s Predators are flown by teams at Langley Air Force Base in Virginia, while the Air Force’s UAVs are run out of Creech Air Force Base in Nevada. Both locations are more than 6,000 miles from their target zones in Iraq, Afghanistan, and Pakistan.

Substantial satellite bandwidth is required to support many Global Hawk and Predator missions. These aircraft use satellite bandwidth to ship sensor data acquired over Iraq, Afghanistan, and Pakistan back to Beale AFB, Calif.; the Pentagon; Central Command Headquarters in Tampa, Fla.; and Langley AFB, Va.; as well as the Central Intelligence Agency in suburban Virginia. The Global Hawks are flown by pilots at Beale AFB, Calif., while Air Force Predators and Reapers are flown from Creech AFB, Nev. The CIA Predators and Reapers, as mentioned previously, are piloted from Langley AFB, 150 miles south of Washington, D.C.

Most RQ-4 Global Hawk operations have been centralized at the 12th Reconnaissance Squadron at Beale AFB, operating out of a facility that looks a lot like space shuttle Mission Control in Houston. Pilots within the Launch and Recovery Element (LRE) are linked by satellite to wherever in the world their mission’s Global Hawk is being operated from.

LRE pilots do not fly Global Hawks with a yoke or stick, but simply a mouse. They command the software to execute the takeoff and fly it to a designated location where pilots and sensor operators involved in the reconnaissance mission take over control of the flight.

Both the LRE and Mission Control Element (MCE) operations often involve highly classified operations and the launch and recovery pilots may have little insight into the intelligence mission, especially if it involves Top Secret/Compartmentalized Information (SCI) a formal designation. Once the recon mission is completed, the MCE pilots return the aircraft to an assigned location, where the recovery pilots land the aircraft, which may have been aloft as long as 32 hours after spending as long as 24 hours over its target area.

Predators and Reapers, along with Global Hawks as well as Tier II and Tier I UAVs, generate huge amounts of data. “We are going to find ourselves swimming in sensors and drowning in data,” said Lt. Gen. David Deptula, assistant Air Force chief of staff for intelligence, surveillance, and reconnaissance.

In 2009, U.S. UAVs alone generated 24 years worth of video if watched continuously, according to Defense Industry Daily. “New UAV models are expected to produce 30 times as much in 2011,” the Web site reported.

“The U.S. Air Force flies 39 orbits over Afghanistan and Iraq every day, and the service expects that number to increase to 50 by 2011,” noted Defense Industry Daily. An orbit is a 24-hour combat flight by a single UAV. The Air Force requires two shifts of operators per orbit for its long-endurance UAVs. Increasing the number of orbits to 50 next year is expected to double the requirement for operators.

“New technological developments are expected to compound the data explosion problem. For example, the USAF is planning to add a wide area airborne surveillance sensor to the Reaper and, eventually, its other UAVs. This system alone is expected to add 50 video streams per sensor within a few years,” Defense Industry Daily reported. The USAF is aiming to have a version deployed on the Reaper by later this year.

Many more UAVs of all sizes are being procured by the Air Force, Navy, Marine Corps, and Army and related special operations forces units. “Analog FM links used on the majority of fielded UAVs consume 20-25 MHz of bandwidth, and channel spacing often has to be even greater than that,” said Gardner at Enerdyne in the Milsat Magazine commentary. “It is very difficult to have more than three or four UAVs operating in a given region when bandwidth is consumed in such a wanton fashion,” he said.

“Realizing the DoD vision of large numbers of UAVs operating simultaneously will require a very different approach. Many UAVs are in the process of the necessary first step: transitioning to digital transmission. But without a holistic view of the spectrum management problem, the industry is likely to find itself confronted by another retrofit cycle in five years,” Gardner said.

According to a study by Northern Sky Research (NSR), the Pentagon by as early as 2014 should have close to 30 Gbps of capacity based on its next-generation satellite program deployments.

“It is unclear whether this capacity will be adequate or whether the U.S. military is close to becoming self-sufficient. But as developments around the globe continue to put strains on internal capabilities, the need for commercial capacity would appear to continue, if only to achieve some sort of flexibility for military bandwidth planners,” according to NSR.

Iraq and Afghanistan and now Pakistan are requiring ground troops, aerial support, and (to a lesser extent) maritime capabilities. Other trouble spots could develop in the near term, including, but not limited to:

• Greater UAV surveillance of North Korea. Continued or even increased piracy in the Horn of Africa that requires greater naval UAV support to safeguard shipping, including oil tankers;

• Preparation for the deterrence of Russia in flexing its muscles in the former Soviet Republics;

• Greater instability in the Middle East; and

• Increased UAV activity in the war on drugs.

The Northern Sky study predicts “future satcom requirements are likely to further increase such that managing the bandwidth, hardware and software available to militaries around the globe will be a tremendous challenge. In enabling the warfighter, the mix and the management of proprietary and commercial satellite capacity will have to be fairly easy and seamless in order for the warfighter to continue to be effective.”

The USAF has increased the number of UAVs over the last two years by 330 percent. It plans to shift 3,600 manpower billets to analyze data streaming from UAVs. It is also doubling the number of ISR liaison officers assigned to ground forces to assist with integration of UAV data collection and exploitation.

According to a Rand Corp. analysis, “the Department of Defense cannot afford to own all the satellite communications capacity it might need in all areas of the world.

“DoD planners estimate that they will need to provide about 16 Gigabits per second of bandwidth by [the end of this year] to effectively support a joint-service operation. However, given current procurement plans, the DoD will own only one-eighth of this projected desired capacity.

“For the foreseeable future, the DoD will need to buy at least some of its communications capacity from commercial vendors. An ability to understand what drives growth in worldwide satellite capacity and to predict capacity would be useful to military communications planners in making decisions in advance to purchase and lease communications capacity in various parts of the world.”

Adjustment to change is quite rapid; if there is an imbalance in the long-run equilibrium between supply and demand, on average 25 percent of the adjustment is made within one year, according to Rand. “The analysis indicates that the market can adjust swiftly to a surge in demand, and thus there may be little need to buy satellite capacity in advance simply to ensure that capacity will be there if needed,” it said.

According to Northern Sky Research, the Pentagon’s recent budget request to buy 50 more extended-range UAVs sent a strong signal to the commercial satellite industry that more “communications-on-the-move” capability for UAVs would be needed in the coming years.

With about 24 more MQ-9 Reapers budgeted for 2011, the Air Force is acquiring more pilotless aircraft than manned combat units, while the Army is planning to procure 26 more Predators than it currently has. With that, concurrent UAV flights are expected to reach 65, up from 37 today, reported the Northern Sky assessment. “What this means for commercial satellite operators is a 75 percent increase in potential clients to serve.”

U.S. Secretary of Defense Robert M. Gates recently shifted the focus of the U.S. military toward more nimble and flexible forces, able to deploy at many sites simultaneously. Following this logic, the use of UAVs to complement other means of observation for in-theater operations and tactical use is set to expand significantly in the years ahead. “We will continue to see significant growth [in drone use] for some years into the future, even as the wars in Iraq and Afghanistan eventually wind down,” Gates said.

This article was first published in The Year in Defense: Aerospace Edition, Summer 2010.