Cellular Backhaul in Asia: Telcos Embrace Satellite

Asia is a beautifully unique juxtaposition; it is the Earth's largest and most populous continent, punctuated by numerous heavily built-up areas and a plethora of rural, underdeveloped communities. Asia is home to some of the planet's most savvy technology pioneers and a living showcase of some of the most deep-rooted traditions. It is ultra modern, yet steeped in ancient culture; and its geography is as varied as its people, languages and creeds.

Having so much to offer, it isn't surprising that Asia provides an ample marketplace for satellite. And as the onslaught of High-Throughput Satellites (HTS) continues to dissolve the stodgy perception that satellite is too expensive, usage will likely increase exponentially. Satellite provides quick-to-deploy solutions and helps telecom operators overcome geographical challenges to extend their coverage to areas punctuated by mountainous features or underdeveloped islets — satellite is key to connecting Asia.

Of course, as connectivity within the continent increases, so does cellular backhaul demand, and satellite-based backhaul, after seeing significant growth, will keep its prominence in Asia. According to Stephane Palomba, vice president of global cellular services at SpeedCast, HTS, the roll-out of 5G and LTE, and broadband trends will spur satellite demand for cellular backhaul for years to come.

"With new LTE licenses popping up in every country in Asia and the growth of broadband services in rural areas, there is now a strong need for satellite services everywhere, not only for coverage matters but also for fast acquisition of new customers. Competition is severe in most countries and too many licensed operators drive service prices down. Hence subscriber acquisition is key for many operators. There has been huge growth of satellite-based backhauling in Asia and 5G/LTE rollout is the major opportunity for cellular services. The need for bandwidth will be multiplied by at least 10 in rural areas. In Japan, rural sites, for instance, are peaking at 100Mbs using VSAT. Full broadband coverage is a challenge in Asia," says Palomba.

Challenges

Demand in Asia for cellular backhaul by satellite is certainly there, but so are difficulties. Cellular backhaul projects are far more complex than basic IP network connections because of the real-time nature of the voice and data traffic in the network. This can become even more challenging if the project involves existing equipment and infrastructure, because not only is Asia's varied geography defined by mountainous regions, vast terrain and a multitude of Islands, but also because most operators have strict Service-Level Agreements (SLAs) for performance to guarantee a high level of quality for their users.

"There is also regulation to consider," adds Palomba. "Regulations are very different from one country to another, and this might limit the expansion of satellite services. SpeedCast has been expanding its network of partners to be able to be present in most countries in Asia."

Altering needs is another challenge, says Mohamed Youssif, COO of ABS, adding that it is not only important to understand each Asian market's needs, but to consider these requirements within the physical context of that particular market.

"In a region as diverse as Asia-Pacific, the needs of each market, from remote Pacific islands to densely populated cities and emerging countries, vary quite widely. Data, government and mobility connectivity are calling for greater capacity and faster speeds with increased performance and lowered cost. It is important to ensure the satellite backhaul connectivity can be served by the most appropriate solution to ensure cost effectiveness," says Youssif.

Within the space segment, it is important that operators find the satellite with proper coverage to serve the areas of interest. Said operator must also have a sufficient elevation angle to clear the ground blockage. Additionally, the band of operation needs to be determined, which is why it is important to consider the market's geography and climate. C-band is ideal for high rain-fade areas, and Ku-band for moderate to low rain-fade areas, while Ka-band only works best in very low rain rate areas. Finally, the beam and transponder with sufficient downlink Effective Isotropic Radiated Power (EIRP) level to provide effective capacity throughput needs to be chosen.

Within the ground segment, antenna size, transmission technology and data packets need to be considered. While a larger antenna has a higher capex, it also enables a higher throughput and, hence, lower opex. Transmission usually uses Digital Video Broadcasting-Satellite Second Generation (DVB-S2) protocol in the gateway-to-remote direction. For the remote-to-gateway direction, though, Single Channel Per Carrier (SCPC) is preferred for high-traffic cell sites whereas Time Division Multiple Access (TDMA) is preferred for low-traffic cell sites. Use of optimizer will improve the packing efficiency of the data packets.

"Tuvalu Communications, BlueSky and FSM Telecommunications Corporation (FSMTC) are great examples of companies that ABS is in partnership with, for the ongoing need for high availability widebeam C-band services to meet the critical communications needs in the Pacific region," says Youssif.

Widebeam capacity may be best suited for these examples within their geographical markets, however, for other more densely populated markets, HTS capacity is best.

With an array of satellite capacity designs and frequencies at its disposal, ABS sees opportunities not only continuing but expanding in Southeast Asia, South Asia and the South Pacific, with trends proving similar in other parts of the world including the Middle East and North Africa, Africa, Latin America, and Russia, says Youssif.

Rural Areas

Satellite will likely always remain the most affordable solution for Asia's rural areas and remote locations. As telecom providers look to expand business, they will have to find new subscribers and users within these rural areas. This means the trend of partnerships with satellite providers will continue on an increasing scale. Earlier this year, such a tie-up was seen between SoftBank and Gilat. Following successful field trials, SoftBank, a Japanese provider of mobile and fixed-line communications services, will be using Gilat's satellite-based cellular backhaul technology to deliver high-speed LTE services to customers in remote areas. Commercial services will be using Gilat’s SkyEdge 2-c Capricorn VSAT network.

Using this satellite-based technology, SoftBank will be providing high-speed services in mountainous regions, remote islands and other areas in Japan where it is economically unfeasible and time-consuming to install fixed-line backhaul. This is not the first time that SoftBank has implemented satellite-based backhaul in these areas, however, with the solution provided by Gilat, SoftBank will be able to provide LTE speeds for the first time. Beyond rural areas, SoftBank has also implemented satellite mobile backhaul on populated islands in Japan, and this is even though the narrow country has highly developed terrestrial infrastructure, indicating how satellite has become an affordable solution that is able to compete with terrestrial solutions.

"We recognize that the satellite-based cellular backhaul market for 2G and 3G is increasing year by year," says Akihiko Tajika, deputy director of the satellite business promotion department at the Solution Advancing Office at SoftBank. "SCPC has been a significant satellite technology but TDMA is seemingly becoming more prevalent in the satellite market in recent years due to its cost-effectiveness and high speed."

Growth in LTE and 3G in many countries across Asia is not tapering off anytime soon, says Tajika, and this will remain a strong driver of cellular backhaul demand. Cost effectiveness, he adds, is as much of an important factor as circuit throughput.

"Such satellite solutions, being focused on both affordability and throughput, are ideal for a country like Indonesia, for example. It has many populated islets and deploying terrestrial networks is overly challenging. While LTE and 3G is driving demand for cellular backhaul, cost effectiveness and high speeds is what is driving demand for satellite to be used to meet the cellular backhaul needs. We believe this trend in satellite-based backhaul will continue for as long as there is technological innovation that keeps cost and speed in focus," says Tajika.

Considering throughput, latency and cost, terrestrial solutions may be feasible for developed areas that are not lacking in infrastructure, says Tajika. But in places where there are no terrestrial solutions existing, then satellite will always be the most affordable, fastest and efficient way. While the industry has done well to reposition satellite as being more affordable, thanks to the advent of HTS and improved efficiencies, more still needs to be done, says Tajika, pointing to the dubious expectations that many held while SoftBank did the field trials with Gilat.

"Many mobile operators believed that the satellite-based cellular backhaul solution would be very expensive and only able to provide low speeds. However, through the field trials it was proven that the satellite solution, with this developed technology, can realize lower cost and higher speed than the terrestrial solution," says Tajika.

While the technology was developed to cover LTE services, Tajika believes that it would be suited for 5G cellular backhaul if it had similar interface specification between a base station and its core system.

Cellular Connections: The Numbers

According to “The Mobile Economy 2016” report issued by the GSM Association (GSMA), there were 4.7 billion unique mobile subscribers globally at the end of 2015, a figure that is equivalent to 63 percent of the world’s population. By 2020, almost three-quarters of the global population will have a mobile subscription, with around 1 billion new subscribers added over the period.

While the report shows that developed markets are growing more slowly, Sub-Saharan Africa and Asia-Pacific are recording significant growth. According to the report, between 2010 and 2015, Sub-Saharan Africa, which is still the world’s most under-penetrated region, saw an annual subscriber growth of more than 13 percent. Representing the world’s largest region in terms of subscribers, Asia-Pacific grew at an annual average of more than 10 percent.

The slowdown in developed markets is due to saturation, with only marginal subscriber growth remaining. This will force operators to rural and underserved communities in a bid to gain new subscribers. This trend of tapping rural areas will also be seen in Africa and Asia-Pacific even though these emerging regions are not expected to see a significant subscriber growth slowdown. This trend means that satellite, in the case of Asia's many islands and infrastructure-lacking areas, will have to play a vital role in meeting the subsequent cellular backhaul demands that will come on the back of increasing mobile users.

Despite annual subscriber growth slowing down in developed countries, these markets will account for more than 90 percent of the 1 billion incremental subscribers expected over the next four years. The developed world will grow from a penetration rate of 84 percent in 2015 to 88 percent in 2020, while the developing world will grow from 59 percent to 70 percent during the same period. With a penetration rate of 59 percent, developing markets have significant room to expand, but, according to the report, numerous factors will hamper growth. These include challenging economic conditions, lower income and purchasing power, uneven distribution and quality of infrastructure, and social and political instability in a number of markets. Considering these factors with the challenges posed by providing coverage to sparsely populated underdeveloped areas, robust subscriber growth can only be realized with the use of satellite. Accessing these areas would prove too costly, in terms of both money and time, with terrestrial solutions. VS