Transformational Wideband Communication Capabilities for the Warfighter

WGS Mission

The Wideband Global SATCOM (WGS) satellites are the key elements of a high-capacity system that will provide a quantum leap in communications capabilities for the warfighter.

WGS will support the DoD's warfighting information exchange requirements, enabling execution of tactical command and control, communications, and computers; intelligence, surveillance, and reconnaissance (C4ISR); battle management; and combat support information. WGS will also augment the current Ka-band Global Broadcast Service (on UHF F/O satellites) by providing additional information broadcast capabilities.

Each WGS can route 2.1 to 3.6 Gbps of data -- providing more than 10 times the communications capacity of the predecessor DSCS III satellite. Using reconfigurable antennas and a digital channelizer, WGS also offers added flexibility to tailor coverage areas and to connect X-band and Ka-band users anywhere within the satellite field of view. The system provides tremendous operational flexibility and delivers the needed capacity, coverage, connectivity and control in support of demanding operational scenarios.

Boeing was awarded the WGS initial contract in January 2001 for the first three satellites plus the associated ground-based command and control elements. Integrated logistics, training, and sustaining engineering support are also provided by Boeing. The procuring agency is the U.S. Air Force Space Command's MILSATCOM Systems Wing at Los Angeles AFB, California.

The WGS space segment will initially consist of three geostationary satellites operating over Pacific, Indian and Atlantic regions. Under a Block II contract, a fourth and fifth satellite are being procured to meet the warfighter's evolving SATCOM bandwidth requirements. The Block II satellites will be similar to the three Block I satellites already in production and will add a radio frequency bypass capability designed to support airborne intelligence, surveillance and reconnaissance platforms requiring ultra-high bandwidth and data rates demanded by unmanned aerial vehicles.

The first Wideband Global SATCOM satellite was launched Oct. 7, 2007 aboard an Atlas V Launch Vehicle. The second was launched Apr. 3, 2009 also on an Atlas. WGS is providing transformational capabilities supporting government objectives for the Transformational Communications Architecture in the next decade and beyond.

Boeing was awarded the WGS initial contract in January 2001 for the first three satellites plus the associated ground-based command and control elements. Integrated logistics, training, and sustaining engineering support are also provided by Boeing. In 2006, Boeing was authorized to produce two additional WGS satellites. The procuring agency is the U.S. Air Force Space Command's MILSATCOM Systems Wing at Los Angeles AFB, California.

WGS is providing transformational capabilities supporting government objectives for the Transformational Communications Architecture in the next decade and beyond.

Capacity:

WGS supports communications links within the Government's allocated 500 MHz of X-band and 1 GHz of Ka-band spectrum. The WGS payload can filter and route 4.875 GHz of instantaneous bandwidth. Depending on the mix of ground terminals, data rates and modulation schemes employed, each satellite can support data transmission rates ranging from 2.1 Gbps to more than 3.6 Gbps. By comparison, a DSCS III satellite will support up to 0.25 Gbps.

Coverage:

The WGS design includes 19 independent coverage areas that can be positioned throughout the field of view of each satellite. This includes eight steerable and shapeable X-band beams formed by separate transmit and receive phased arrays; 10 Ka-band beams served by independently steerable, diplexed antennas, including three with selectable RF polarization; and transmit/receive X-band Earth coverage beams.

Connectivity:

The enhanced connectivity capabilities of WGS enable any user to communicate with any other user with very efficient use of satellite bandwidth. A digital channelizer divides the uplink bandwidth into nearly 1,900 independently routable 2.6 MHz subchannels, providing connectivity from any uplink coverage area to any downlink coverage area (including the ability to cross-band between X and Ka frequencies). In addition, the channelizer supports multicast and broadcast services and provides an effective and flexible uplink spectrum monitoring capability to support network control.

The figure below shows how the X-band and Ka-band antenna suites are interconnected via the digital channelizer to provide the unique flexibility and connectivity of WGS.

Command and Control: Control of the WGS communications payloads is accomplished from four Army Wideband Satellite Operations Centers (WSOCs), using ground equipment hardware and software developed by Boeing, ITT Industries, and Raytheon Corp. Each Global Satellite Configuration and Control Element (GSCCE) has the capability to control up to three satellites at a time, via "in-band" (X-band or Ka-band) telemetry and command links. Spacecraft platform control is accomplished by the 3rd Space Operations Squadron (3 SOPS) at Schriever AFB in Colorado Springs, using WGS mission unique software and databases provided by Boeing, hosted on the Command and Control Segment Consolidated (CCS-C) systems that are being fielded by Integral Systems, Inc. The satellite is designed for compatibility with the current S-band SGLS TT&C capability, as well as the planned Unified S-band (USB) formats and frequencies.

Boeing 702 Platform :

The Boeing 702 satellite is the industry leader in capacity, performance and cost-efficiency. Enabling technologies for the advanced 702 design are the xenon-ion propulsion system (XIPS), highly efficient triple-junction gallium arsenide solar cells, and deployable radiators with flexible heat pipes.

XIPS is 10 times more efficient than conventional bipropellant systems. Four 25-cm thrusters remove orbit eccentricity during transfer orbit operations and are used for orbit maintenance and to perform station change maneuvers as required throughout the mission life. Deployable radiators with flexible heat pipes provide substantially more radiator area, resulting in a cooler, more stable thermal environment for both bus and payload. This increases component reliability and reduces performance variations over life.

Summary

Move over, Buck Rogers

X-45 is showing it has the mettle to fly toughest missions

BY WILLIAM A. BARKSDALE

The night is eerily calm, the darkness foreboding. A U.S. pilot pulls on a G-suit and helmet and climbs into an aircraft not knowing what the future holds. As the jet climbs over the desert skies, adrenaline is pumping because this is for real.

The highly trained airman has entered another world, one where thousands of lights dart up from the ground with no warning, each one seemingly aimed his way. This would be the greatest fireworks show ever witnessed if it were not deadly. It's no game. It's warfare, it's dangerous, and there's nowhere to hide.

Known as Suppression of Enemy Air Defense, the mission is simple. Fly into harm's way and become human bait, a target for air defenses. Once the ground missile site turns on its radar and prepares to launch a strike, the chaos begins. If the threat can't be destroyed, other pilots will die.

SEAD takes a unique breed, a special type of warrior--and Dick Ewers fits that description. As a U.S. Marine Corps aviator in Vietnam, he flew the mission in his F-4 Phantom and still remembers it well.

"When you fly SEAD, you're the first guy in and you're getting shot at. I'd say 90 to 95 percent of the airplanes we lost were due to a ground threat," Ewers said. "SEAD was and is a very lethal mission in which you can lose a lot of people if you don't plan it right. It's not something you want to do without a lot of friends helping you."

Retired from the Marine Corps since 1989, Ewers now works as a NASA research pilot at Dryden Flight Research Center at Edwards Air Force Base, Calif. One of his assignments is to "fly chase" on an advanced experimental aircraft known as the X-45, and it takes him right back to some very harrowing moments in Southeast Asia.

"When I was in Vietnam, I lost three of my closest squadron mates due to enemy ground fire," recalled the fighter pilot. "If we'd had an unmanned combat vehicle like the X-45 flying then, a lot of pilots might have been saved."

* * *

As the first unmanned air vehicle designed specifically for SEAD, and with the potential to deliver a revolutionary improvement in effectiveness, the Joint Unmanned Combat Air System X-45 is being watched closely by many in the defense industry.

The X-45 is a Defense Advanced Research Projects Agency, U.S. Air Force, U.S. Navy, and Boeing Integrated Defense Systems program that also involves NASA. Boeing developed and built two X-45A demonstrators and is working on an X-45C demonstrator. The program's purpose is to demonstrate the technical feasibility, military utility and operational value of an unmanned combat air system for the military.

"This is a revolutionary aircraft because it is designed to think and act like aviators do without having an aviator control it," said U.S. Air Force Lt. Col. James "Pee Wee" Wertz, 452nd Flight Test Squadron commander and Global Vigilance Combined Test Force director at Edwards. "No one has to move a stick and throttle to tell this airplane what to do. As a matter of fact, its autonomy will allow an operator in the future to monitor four unmanned vehicles at once, each with a separate mission plan."

Flashing a huge grin, Wertz used his hands to describe a possible scenario. "Imagine a four-ship formation of X-45s making their way to a heavily protected area. Vehicle One is loaded with weapons and is primary to strike the target. Vehicle Two will blind the enemy's radars buy using its electronic combat capability. Vehicle Three will gather photos after the strike for battle damage assessment, and Vehicle Four will have a different munitions load as a backup to the first aircraft. As they are flying along, out pops a change in targets and the weapons in Vehicle Four are now the best ones available to execute the mission."

Wertz took a huge breath and leaned forward. "All four vehicles understand and react to the change real-time, deliver the munitions on target and bring back the evidence. Now that's truly amazing. That's Buck Rogers-type stuff."

As exciting as Wertz's description is, an important question comes quickly to mind. How long will it take to deliver such a transformational capability to the U.S. warfighter?

In the past, the development, operational testing, evaluation and fielding of a new weapons system could take decades. But Boeing has listened closely to its customers and plans on delivering aircraft before the end of the decade.

That might sound impossible, but a small band of innovators is making it happen by flying two technology demonstrators at Edwards. Interestingly enough, Edwards has hosted more than its share of historic events, none perhaps more famous than when a young test pilot named Chuck Yeager became the "fastest man alive" by breaking the sound barrier on Oct. 14, 1947, in the Bell X-1.

Making its own history, the X-45A demonstrator already has achieved a first in aviation by dropping a 250-pound inert Small Smart Bomb from an internal weapons bay on March 21 over a remote Southern California desert test range.

Rob Horton, Boeing IDS chief X-45 operator, is proud of this aircraft and is not shy about singing its praises. "The X-45 is a force enabler because it allows the human to be a top-level battle manager, a commander, rather than someone who just physically flies the airplane," he said.

When confronted with the criticism that unmanned aircraft are inherently dangerous and hard to control, Horton, a former U.S. Air Force test weapons system operator and navigator, replied quickly: "There is always a human in the loop. I give the command consents that allow the vehicle to taxi, take off and drop weapons. If there is an emergency, the aircraft's reaction has been preprogrammed through intelligent software that allows it to handle almost anything. It can either deal with the problem or return to base without help. We can even override the autonomous reactions and keep it flying toward the target."

That level of control and the ability to interoperate with manned aircraft was clearly demonstrated in a March flight when the X-45 was returning from a test mission. A nearby T-38 pilot declared an in-flight emergency when the unmanned vehicle was on final approach with gear down. The Boeing mission team successfully sent the X-45 around the pattern to allow the other aircraft to land quickly.

So what lies ahead? The program's most recent success took place April 18 when the X-45A dropped an inert precision-guided weapon on a ground target. With that accomplished, the team must now face a critical milestone: coordinated flight operations. The first step will be to demonstrate cooperative flight and inter-vehicle operations between the X-45A and a manned T-33. On another flight, a ground operator will control both aircraft. And finally, both X-45A aircraft will fly together and demonstrate autonomous coordinated flight.

While the X-45A flies numerous test missions and rewrites aviation history, Boeing IDS Vice President and Program Manager Darryl Davis and his 600 teammates in Washington, Arizona, California and Missouri will develop an advanced version, the X-45C, for an early operational assessment for the U.S. Air Force and the U.S. Navy. The X-45C will be much larger than the A demonstrator.

The C will be 39 feet long with a 49-foot wingspan. Despite being only a few feet thick, its maximum payload will be 4,500 pounds and it'll be able to carry eight Small Diameter Bombs--Boeing's newest near-precision 250-pound weapon. This revolutionary combat vehicle will cruise at 0.85 Mach and fly at 40,000 feet with a mission radius of 1,300 nautical miles.

As far as its purpose, the U.S. Air Force has expressed its intent to use the X-45C for SEAD, and that makes Dick Ewers glad. "I easily expect the X-45 to be 10 times more accurate than I ever was in an F-4," the combat veteran said.

Lieutenant Col. Wertz sums up the value of the program best. "If we send a pilot on a dangerous mission to a highly defended location, we run the risk of killing him. With the X-45, we may lose an aircraft to that same mission, but that's far better than sacrificing a human life," he said. "With this system, the mission operator can execute the tasking from a computer station here in the United States and return home in time to tuck his children into bed and have dinner with his wife. That is why this is so amazing."

Move over Buck Rogers, indeed.