Satellite-Terrestrial Networks: Revolutionizing Remote Communications
Dr. Ashok Rao, Director of Product & Technology
Strategy, SkyTerra Communications

In today’s “always-connected” world, consumers now consider reliable wireless communications critical. Co-workers, friends and family demand the ability to connect with each other from anywhere, at any time, via not just phone calls, but also email, social networking tools and other online applications.

But for professionals working in remote industries, dependable connectivity is truly crucial. In many cases, their lives even depend on it.
Teams employed in oil and gas, mining/exploration and forestry typically work in rural and remote locations. The conditions are often dangerous and require careful coordination and collaboration; yet, terrestrial wireless networks are usually nonexistent or spotty. Enterprises realize that the ability to communicate with employees in these environments and remotely monitor equipment situated in these areas is invaluable, helping to increase productivity as well as ensure workers’ safety.

Satellite communications currently plays an important role in enabling such critical communication and, with the next-generation of satellites on the horizon, enterprises can look forward to technologies that meet their needs even more effectively in the very near future.

The Role of Satellite Technology in Enabling Communications
Satellite communications emerged in the 1960’s and continues to meet the needs of remote industries today. For both day-to-day and emergency communications, satellite provides reliable communication when land-line and wireless networks are not available.
The military was the first to make use of satellite communications, using Fixed Satellite Services (FSS) to establish connections with soldiers stationed in regions outside of terrestrial coverage. Private telecommunications companies soon followed, using satellite to provide international telephony.

In the 1970’s, mobile satellite services (MSS) became available, expanding satellite’s capabilities. Instead of just installing a satellite terminal and antenna at a base camp, the military could equip their trucks, ships and aircrafts with satellite terminals. The private sector soon followed, allowing customers on cruise ships and air planes to make phone calls via satellite. And broadcast journalists realized that they could enhance their coverage of world news by broadcasting from remote areas using satellite technology.

FSS and MSS are categories of radio services that have been defined by the International Telecommunications Union (ITU), the international body responsible for standardizing and regulating international radio and telecommunications. FSS is provided by geostationary satellites which are located 22,300 miles above the equator. The ITU has allocated spectrum in C-Band, Ku-Band and Ka-Band for FSS services. The allocated spectrum is reused by multiple satellites located at different locations along the geostationary orbit. To prevent harmful interference among the satellite networks, the earth terminals being served by a particular satellite have must have antennas with narrow beams and be pointed accurately towards their respective satellites. The terminals have to be relatively large (at least about two feet in diameter for Ka-Band, and larger for Ku-Band and C-Band) to obtain the required level of directivity. In contrast, within the MSS category, there are both geostationary and non-geostationary satellite networks. The practicalities of mobile operation tend to limit the size of the mobile terminal antennas that can be used. Small antennas have relatively broad or even omnidirectional beams. Thus, a given terminal antenna “sees” a large range of orbital locations, and therefore within a geographical area, portions of the allocated spectrum are usually dedicated to the satellite networks covering that area.

By the 1990s MSS providers such as Inmarsat, Iridium, GlobalStar, and SkyTerra Communications (previously Mobile Satellite Ventures) began launching larger, more powerful satellites. The more powerful satellites, which require smaller antennas to send and receive signals to the satellite, paved the way for the development of satellite phones, which are small enough to be carried by individuals such as soldiers, rescue teams, pipeline workers, forest rangers and others working in remote areas.

In addition, machine to machine (M2M) communications in areas without terrestrial coverage was made possible by mobile satellite equipment, enabling enterprises to conduct remote monitoring and collect data without sending an employee to the location. M2M communications includes such applications as supervisory control and data acquisition (SCADA), which are used extensively by power, water, gas and other utility companies to monitor and manage distribution facilities, and applications such as Automated Meter Reading (AMR) and Advanced Metering Infrastructure (AMI), which are used to monitor, measure and control end-user usage levels. This saves employee time, increases efficiency and, in many cases, protects employees from dangerous situations.

The development of vehicular satellite systems by MSS providers was also extremely valuable, allowing government, public safety and enterprise to communicate on the go.

Mobile satellite data terminals brought advanced and low-cost global wireless data communications. Over land, sea and air, the technology enabled a variety of enterprise applications such as event reporting, emergency response, worker protection, dispatch coordination and messaging in near real-time. Over the years, satellite communications continued to advance and, in 1995, the Global Positioning System (GPS) became operational. GPS is now used on a regular basis by military, government and enterprises as well as consumers, aiding in navigation, map making, tracking and monitoring. Today, many cellular and satellites phones and vehicle systems also include GPS receivers, enabling fleet and asset tracking, and helping individuals use maps more effectively.

While current satellite phones offer remote industries many advantages, limitations still exist. Satellite phones provided by Iridium and GlobalStar, while supporting voice calls with decent quality, can only sustain low speed data transmissions. That typically means that downloading email or browsing a website takes much longer, as much as five to 10 times slower than a dial-up connection. However, today business professionals rely on higher-bandwidth applications in their daily communications. Not only do enterprises need their employees to access email and run web-based applications on the go, but they also want the ability to send and receive image and video files to increase productivity and provide remote support. In addition, current satellite phones are much larger than contemporary cellphones and cannot easily be a substitute for a worker’s cellphone. This means that there is yet another item for the worker to keep charged and carry in their toolkit.

The introduction of Inmarsat’s Broadband Global Area Network (BGAN) in 2005 set out to address these limitations. The technology has allowed field staff to send to their home office data such as images, video and project updates. The ability to share this type of information, conduct Internet research while on site, and receive remote assistance if needed via live audio and video makes a great impact on productivity. Prior to the arrival of BGAN, companies would send employees to a remote location to gather information and then those employees would have to travel miles in order to find an Internet connection that would allow them to send the information back to the office.

BGAN terminals have enabled a significant improvement in remote communication capabilities, however, the technology still faces many of the challenges encountered with traditional satellite phones. Today, employees are used to small, user-friendly handheld cellular devices for communication. Ranging in weight from a kilo to about three kilos, BGAN terminals are still significantly larger and heavier than handheld devices such as smart phones, making them difficult for workers in the field to carry all the time. Thus, if there is an emergency that requires instant communication with home offices, workers would still need to get to their BGAN terminal, which might be a distance away. In addition, since the equipment might not be carried throughout the day, if it was needed in an emergency, there is a risk that the terminal might not be charged. Being a specialty device, some amount of end-user training is required for satellite equipment to be used, which could potentially create problems when untrained individuals attempt to use the terminal during a crisis.

The Future of Satellite Communications
Satellite technology has advanced significantly over the last 30 years but the future looks even more promising as MSS companies such as SkyTerra and Terrestar develop integrated satellite-terrestrial chipsets and modules.

These next generation dual-mode devices will allow individuals, for the first time ever, to communicate from virtually anywhere in the U.S. and Canada, seamlessly switching between cellular and satellite network. Thanks to more powerful satellites and satellite-enabling chipsets, these individuals will be able to communicate over satellite and cellular networks with handsets similar in aesthetics, cost, form factor and functionality to what is on the mobile phone market today.

As smart phones continue to become a popular choice among consumers, they are forecasted to grow to over three hundred and forty-four million units shipped worldwide in 2014 according to ABI Research, the demand by remote workers to have the same type of capabilities they are used to receiving in urban/suburban areas is likely to increase.

Next-generation devices offer the promise of virtually ubiquitous outdoor coverage throughout the footprint of the satellite system. A remote worker can use the same mobile device on the job as he/she uses everyday to communicate with family, friends and co-workers. This means no special training is needed to use the phone and special activation or periodic testing is not required. If an emergency arises, a worker merely needs to pick up and dial.

Building on its current mobile satellite push-to-talk (PTT) service, SkyTerra’s next-generation handsets will also offer PTT enabling remote workers to connect with other PTT users (one-on-one or as a group) at the push of a button (i.e. “walkie-talkie” style).

In addition to phones, next-generation dual-mode modules will be developed, which could be easily integrated into mainstream third-party devices such as USB dongles, laptops and netbooks. The technology will also enable a wide-range of telematics services including vehicle security, infotainment and remote diagnostics, unique multicasting applications, as well as Web-based content and mobile broadband services.

Companies making use of these services will save money by only having to purchase one mainstream device (that, thanks to economies of scale, is less costly than traditional satellite equipment), offering the best of both satellite and terrestrial services.
Currently, a remote M2M communications project requires the mixing and matching of different satellite and cellular equipment depending on the cellular coverage available at a site or region and the bandwidth demands of the application. One device, supporting multiple cellular standards and high speed satellite connectivity at an affordable cost, simplifies the implementation and reduces the total cost of ownership.

Status of Next Generation Satellite Communications
In the past year, the telecommunications industry has made significant progress towards making combined satellite-terrestrial communications a reality. Late in 2008, SkyTerra and other MSS operators entered into a 15-year business agreement with Qualcomm to build satellite-enabled chipsets for mobile devices on a mass-market scale. Under the agreement, Qualcomm will integrate satellite and cellular communication technology in select multi-mode mobile baseband chips. For the satellite link, Qualcomm adapted its standard Evolution Data Optimized (EV-DO1) Rev A technology to work over satellite.

Qualcomm will sell and support its chipsets to mobile device vendors in the same manner it does today, but many of those with EV-DO will include an embedded satellite communications capability. This means that the same mobile chipsets forming the heart of handsets and other devices will allow handset vendors to produce satellite-capable devices at comparable scale and cost.

The initial Qualcomm satellite-enabled chipsets will support a range of handhelds and mobile computing devices with 3GPP and 3GPP22 technologies across a wide range of existing mobile terrestrial bands. The chipsets will support the latest 4G LTE standard which will be rolled out by North American mobile operators in 2010.

In addition, in April of 2009, an agreement was signed by SkyTerra Communications and TerreStar with Infineon (formerly the semiconductor division of electronics giant Siemens) to develop a software-defined-radio (SDR) based chipset platform. SDR-enabled satellite-terrestrial handsets will operate with multiple cellular and satellite-based communications technologies including GSM, GPRS, EDGE, WCDMA, HSDPA, HSUPA, and GMR1-2G/3G. Infineon will be incorporating the Hughes developed GMR1-3G satellite air interface protocol in its SDR platform.

The other critical part of the plan to make the next-generation a reality is the launch of satellites powerful enough to close the link with small handsets. MSS companies are in the process of launching new satellites to support the development of next generation satellite-cellular technology. For instance, SkyTerra is planning to launch two of the largest and most powerful commercial satellites ever built in 2010 and 2011. The satellites, with a North America service footprint, will have extremely high receiver sensitivity and along with the efficiency of Qualcomm and Hughes satellite air interfaces will allow for reliable satellite service on a small handset.

Agreements like those formed with Qualcomm and Infineon, who are leaders in the cellular chipset business, are just the first of potentially many partnerships between satellite operators and wireless chipset manufacturers, and illustrate how the two industries are taking advantage of opportunities to offer enterprises and consumers increased geographical coverage and new applications on traditional cellular-sized handsets and other small mobile devices.

For example, this past September AT&T, which is to resell TerreStar's satellite services in remote areas, announced the Genus, a smartphone that uses the MSS network only when cellular coverage is unavailable. This offers connections when the terrestrial network is unavailable or disrupted, but does not impose the higher satellite charges on users who can get onto a cellular system. Previously, MSS subscribers had to have a separate device, usually heavy and expensive, and a separate phone number for the satellite network, but the Genus supports a single number and looks similar to a 3G handset. The price tag however is still fairly hefty running between $800 and $900. Users will sign up for existing AT&T 3G voice and data plans plus an additional $25 a month per device for satellite service, and then pay extra for satellite calls (65 cents a minute for voice, $5 a megabyte for data). TerreStar says those rates are about 50 percent lower than MSS-only offerings available in the US. The Genus is scheduled to be available in the first quarter of 2010, when AT&T will start to market dual-mode services to corporate and public safety customers as well as travelers or residents in very remote areas. Coverage will be available over the whole of North America including Puerto Rico.

Next-generation integrated satellite-terrestrial communications is expected to revolutionize communications for remote industries. Enterprises will no longer need to choose between satellite and terrestrial service. They will get the best of both worlds and value the redundancy and ubiquity of next-generation services. The mass-market scale will lower device and service pricing compared to traditional mobile satellite services, while likely improving service capability and extending utility to existing MSS customers.

References
1) EV-DO is a 3G wireless telecommunications technology that is a major enhancement to CDMA that provides high speed wireless data connectivity
2) 3GPP and 3GPP2 are the third Generation Partnership Projects for the production and standardization of technical specifications for next generation mobile systems based on GSM and CDMA network technologies respectively.

SkyTerra Communications delivers mobile wireless voice and data services primarily for public safety, security, fleet management and asset tracking in the US and Canada. The company’s integrated satellite-terrestrial communications network is expected to provide seamless, transparent and ubiquitous wireless coverage of the United States and Canada to conventional handsets. For more information visit www.skyterracom.com.

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