Reader Forum: A cost-effective solution for rural backhaul

Editor’s Note: Welcome to our weekly Reader Forum section. In an attempt to broaden our interaction with our readers we have created this forum for those with something meaningful to say to the wireless industry. We want to keep this as open as possible, but maintain some editorial control so as to keep it free of commercials or attacks. Please send along submissions for this section to our editors at: [email protected] or [email protected].
Mobile market forces have collided to create several challenges for the wireless industry: Because of ever-growing customer demand, operators are under constant and increasing pressure to expand their network footprints and launch new applications and service bundles. The higher network capacity demanded by those data-intensive services means more expensive network deployment and expansion – even as per-customer revenues decline due to competitive forces.
Penetration rates and competition is typically most intense in urban centers for mobile operators. One of the best ways for operators to remain competitive is by having the most complete coverage maps for a competitive region, which means extending their networks beyond the urban core to the surrounding, outlying areas. As a result, many mobile operators are beginning to build their networks outward, expanding their footprints and services into areas that are more rural but often are still a critical part of their customers’ connectivity requirements.
While that expansion creates many new opportunities for the operator to pursue, it comes with its own set of challenges. Rural regions are typically less accessible from an infrastructure standpoint and have smaller addressable customer populations. Therefore, network buildout and operating costs are usually higher, and potential new revenue generation is lower.
Chief among mobile operators’ concerns in expanding into any region is the cost of backhauling traffic – in particular, backhauling the higher-bandwidth data and multimedia services that makes up an ever-growing percentage of network traffic.
Weighing backhaul options
Backhaul has long been a limiting factor in the profitable expansion of mobile networks, and the problem is only amplified in rural regions. Mobile operators that are expanding their networks have a multitude of backhaul technologies at their disposal. But choosing the proper technology and location is essential to developing a profitable service that will support the number of subscribers in the areas of expansion.
Coverage, efficiency and cost factors, among others, typically are the main points of consideration in choosing a backhaul solution. The costs of terrestrial infrastructure backhaul solutions like fiber and microwave can be prohibitive in rural regions, because of both geography and the increased distance between addressable population centers.
Traditional satellite connectivity has long been viewed as one of the only options for backhaul in rural regions, though it has traditionally been viewed as a niche option for operators. But there is an alternative that operators operating or expanding into rural markets may have overlooked in the past – and given the potential cost savings it’s worth another look.
Efficiency and availability
Our research shows that satellite transmission in the Ka-band will be eight to 10 times lower than Ku-band and C-band transmission. That means that on a per-MHz basis, backhaul infrastructures based on Ka-band transmission can come close to being competitive with traditional T-1/E-1 backhaul infrastructures.
One of the main concerns with satellite transmission is that as you increase in frequency, signals become more susceptible to rain fade. This occurs because of the frequency wavelength: The longer wavelengths of C-band are less susceptible to rain attenuation than the shorter wavelengths in the Ku- and Ka-bands. Therefore, transmission in the C-band typically provides the carrier-grade three to four 9s of availability. At the higher operating frequencies of Ku-band and Ka-band, however, signal strength may be affected by heavy rain conditions. When signal strength is degraded, throughput can be slower – or in extreme conditions, service can sometimes be interrupted.
For operators, those performance limitations typically mean that Ka-band backhaul is considered as a complementary or backup solution for tier one. But considering the cost advantages that can be realized from deploying Ka-band backhaul, and the cost constraints of rural market deployment, we believe the advantages outweigh the disadvantages in rural markets.
Operators that leverage the efficiencies of Ka-band backhaul should be able to successfully and economically expand their networks and get a broader array of services to rural markets with minimal service interruption.