Ka-Band — Future of Satellite Broadband Communications
Satellite network operators say there is a $1.4 billion per year market for high-speed mobile satellite data communications systems and that they can increase connectivity speeds by an order of magnitude with the next generation of high throughput satellites (HTS). That would result in download speeds that are comparable to mobile phone 4G networks on the ground.
HTS vehicles will feature Ka-band transponders in addition to, or as replacements for, Ku-band transponders used on current-generation satellites. Connectivity speeds will be considerably slower aboard aircraft because they have smaller antennas than those used at ground stations or aboard ships. However, Ka-band systems promise to provide as much as 10 times higher connectivity speeds than the best Ku-band satellite systems aboard aircraft today.
Compared to Ku-band, Ka-band has roughly seven times the total frequency spectrum available. Ku-band satellites have 27- to 54-MHz bandwidth transponders that support up to 1- to 2-Mbps download speeds. Ka-band satellites, in contrast, have 300- to 600-MHz wide band transponders that offer about 10 times the bandwidth capacity. Some satcom industry observers believe that Ka-band satellites will provide 10- to 20-Mbps connectivity, depending upon antenna size, avionics and system demand.
Gogo and ViaSat, among other connectivity providers, are developing Ka-band satcom systems. Gogo wants to extend its connectivity globally, so it has to provide other links besides its continental U.S.- and Alaska-based terrestrial stations. ViaSat recently launched its first company-owned satellite, ViaSat-1, claimed to be the world's highest capacity Ka-band communications satellite. ViaSat-1 will offer Ka-band connectivity to land-based users beginning this year.
In April 2011, though,became the first aeronautical customer for Ka-band services by signing a $30 million contract for satcom and Wi-Fi equipment, along with connectivity services, aboard 170 of its and ERJ190 airliners. Installations are slated to begin this year. ViaSat expects to develop a worldwide network of Ka-band satcom services during the coming decade.
Not surprisingly then, Inmarsat wants to leapfrog Ku-band satcom technology with its fifth-generation I-5 communications satellites. They will offer robust Ka-band connectivity in addition to the L-band voice and data communications of the I-4 satellites that were commissioned in 2005. I-5 Ka-band connectivity should make possible 10 Mbps download speeds aboard aircraft fitted with a 12-in. dish antenna, according to Inmarsat.
officials, though, are more conservative in their projections for I-5 Ka-band connectivity. They believe the system will offer roughly double the data capacity of current Ku-band satellites.
Inmarsat is payingmore than $1 billion to build the I-5 satellites that will be based upon Boeing's 702HP space vehicles. The first satellite is slated for launch in 2013 and all three I-5 satellites are expected to be operational in 2014. Expected service life is 15 years.
The I-5 trio will have near global coverage and Inmarsat believes that its Global Xpress connectivity service, using Ka-band transponders offering 500 MHz of bandwidth, will provide aircraft with up to 20 times faster upload and download speeds than the firm's current SwiftBroadband service. Just as importantly, each of the three satellites will have 20 times the data communications capacity of the I-4 space vehicles, thus the system is less likely to bog down with heavy use.
Ka-band also should be a more-efficient data conduit, thereby providing users with a significant cost savings per megabyte of data. The cost benefit projections indeed were sufficiently compelling for Boeing to sign on as Inmarsat's distribution partner and to commit to buying more than 10% of the I-5 satellites' L-band and Ka-band capacity. Boeing's confidence in Global Xpress is driven in part by projected government demand for high bandwidth communications, especially on the battlefield.
However, investing in Global Xpress still is a significant leap of faith for Boeing considering its last foray into broadband satcom data communications, the failed Connexion by Boeing Ku-band system that was in operation for little more than two years between mid-2004 and 2006.
Inmarsat, though, believes its I-5 space vehicles will generate annual revenues of $500 million for the first five years of operations, and its legacy satcom systems are in use aboard 12,000 aircraft, providing plenty of potential customers for Global Xpress. Thus, there should be significantly less investment risk for Boeing. Inmarsat also believes that it has “high potential” to sign on other wholesale distributors prior to commissioning the I-5 constellation.
Rockwell Collins also intends to play a key role in developing Ka-band satcom avionics for end users. In August, it signed an agreement in principle with Inmarsat to be the sole lead for the design, development, manufacture and distribution of Global Xpress avionics and also to provide aeronautical services to the aviation community.
Based on such development, it's apparent that broadband communications will play an increasingly important role aboard business aircraft. With coverage throughout the continental U.S. and Alaska, the Gogo Biz system has the potential to grow to meet increasing demand. Throughout the rest of the world, a new generation of HTS Ka-band satellites, including the I-5 spacecraft that will be launched by Inmarsat, promises to bring high-speed connectivity to business aircraft travelers virtually anyplace they travel. BCA