What is Wideband Global SATCOM?

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Editorial Team - everything RF

May 28, 2020

 

Wideband Global SATCOM (WGS) is a satellite communication system used  by the US Military (DoD), Canadian Department of National Defence (DND) and the Australian Department of Defence. The system has been developed to connect military personnel from these countries around the globe, supporting soldiers, ships, and aircrafts.

In 2001, the US Department of Defense selected Boeing Space Systems to develop WGS system as a replacement for previously used Defence Satellite Communications Systems 3 (DSCS III), which was in operation from 1980 to 2000. WGS systems enhance the DoD’s communication services provided by the DSCS satellites and the global broadcast system (GBS) operating at an ultra-high frequency (UHF). 

WGS provides newer and greater capabilities than DSCS to the warfighter by deploying a constellation of high-throughput satellites to a geostationary orbit. The WGS satellites make use of modern satellite communications systems such as phased array antennas and digital signal processing technology to create a powerful architecture with a high degree of flexibility. 

The WGS system consists of three segments: Space Segment (satellites), Control Segment (operators) and Terminal Segment (users). This constellation of highly capable military communications satellites operates in both the X-band and Ka band. WGS augments the one-way Global Broadcast Service (GBS) through a new two-way Ka-band service. A digital channelizer and reconfigurable antenna allow 19 separate coverage areas connecting Ka and X band users anywhere within the satellites field of view. Digital signal processors and advanced phased array antennas enable shaped steerable spot beams that apply bandwidth exactly where and when the warfighter needs it.

Each standard WGS satellite offers 4.875 GHz of instantaneous switchable bandwidth corresponding to a capacity of 2.1 to 3.6 Gbps depending on the ground terminals, data rates and modulation profiles that are employed. Around 500 MHz of X-band and 1 GHz Ka-band spectrum is allocated to WGS. Each WGS satellite can supply more than ten times the capacity of a DSCS III satellite.

WGS Satellites under construction at Boeing – Image: Boeing Space Systems

Satellites in WGS Constellation

The first three WGS satellites, WGS-1, WGS-2 and WGS-3 form Block I of the space segment. The next three, WGS satellites WGS-4, WGS-5 and WGS-6, make up Block II. The next four, WGS-7, WGS-8, WGS-9 and WGS-10, make up Block II Follow-On.

Block I

The first satellite, WGS-1 was launched into orbit on 10 October 2007 on the United Launch Alliance (ULA) Atlas V launch vehicle. After the launch, the military designated the WGS-1 as USA-195, which entered service in April 2008. The WGS-1 satellite operates over the Pacific region.

The second satellite, WGS-2 was launched into geostationary orbit on the Atlas V in April 2009. The WGS-2 satellite was designated as USA-204, and entered service in August 2009. The satellite operates in the Indian Ocean region and provides high-capacity communication links to US troops in Iraq and Afghanistan.

The third satellite, WGS-3 was delivered to Cape Canaveral Air Force Station, Florida, on 28 September 2009, and was successfully launched in December 2009 on a ULA Delta IV vehicle from Space Launch Complex 41. It has been positioned over the Eastern Atlantic to operate in the Atlantic region. 

Block II

Block II satellites feature a radio frequency bypass capability, which is designed to support airborne intelligence, surveillance and reconnaissance platforms that require ultra-high bandwidth, as well as the data rates demanded by unmanned aerial vehicles. The block II satellites meet the bandwidth requirements of war-fighters, thereby providing information exchange, enabling execution of tactical C4ISR, battle management and combat support information.

The fourth satellite, WGS-4 was launched by United Launch Alliance from SLC-37B at the Cape Canaveral Air Force Station on January 20, 2012. 

The fifth satellite, WGS-5 was launched on May 24, 2013 by a Delta IV rocket flying in the Medium+(5,4) configuration, with lift-off taking place from SLC-37B in Florida. 

The sixth satellite, WGS-6 had been shipped to florida and was launched on a Delta IV rocket on 7 August 2013 from Cape Canaveral Airforce Base.

Block II Follow-On

The seventh satellite, WGS-7 was successfully launched on 24 July 2015 by a Delta IV rocket, with lift-off taking place from Complex 37 in Florida

The Eighth satellite, WGS-8 was successfully on 7 December 2016 by a Delta IV Medium+ (5,4) rocket from SLC-37B at Cape Canaveral Air Force Station in Florida. 

The ninth satellite, WGS-9 was launched on March 15, 2019, by a Delta IV rocket from Cape Canaveral Air Force Station. 

The tenth satellite, WGS-10 is the latest part of a constellation of highly-capable communications satellites that serve the armed forces of the US and its allies. It carries Ka-band and X-band transponders with 8.088 gigahertz of bandwidth – offering downlink speeds of up to 11 Gbps.

In 2019, Boeing received a contract of $605 million to build the eleventh WGS satellite, WGS-11. It is expected to be completed by November 20, 2023.