Spectrum is the lifeblood of mobile services. Any service on the airwaves needs frequencies it can use without being overwhelmed by interference, whether the frequency it uses comes from an exclusive license or from a sharing arrangement. The more packets of data are being exchanged over a network, the more spectrum will be needed to carry them—unless something else is done.
Mobile operators, technology vendors and governments have been sounding alarms about mobile networks nearing capacity for years, and those alarms are getting louder. A study by investment bank Credit Suisse said mobile networks worldwide were filled to 65 percent of capacity on average. With the exponential rise in mobile data traffic and new applications, operators run the risk of overloading their spectrum band, which will slow down users’ mobile experience.
Deloitte predicts that although additional spectrum will continue to be made available in many global markets, spectrum exhaustion will continue to exacerbate in many countries, especially in dense urban areas. End users will continue to see performance impacts as a result, primarily in the form of lower speeds, but also through inability to access networks and dropped calls or sessions. The reason is simple demand for spectrum will exceed supply. Demand for wireless bandwidth continues to grow in leaps and bounds, but supply is relatively constrained. By 2014 the US alone may suffer a 275MHz spectral “deficit”.
Despite widespread calls for more spectrum to carry mobile data, there is a wide range of technologies already being used or explored that could help to speed up networks or put off the day when more frequencies need to be cleared. Government and industry agree that what’s need is at least a two-pronged approach, with more spectrum as well strategies to make better use of the spectrum that is already available.
Some industry experts say it’s time to throw out the whole notion of allocating certain frequencies exclusively to commercial mobile service, or to any exclusive use. Instead, they advocate mobile operators sharing spectrum with current users, such as government agencies. Advances in technology, including small cells and radio performance improvements, help make it possible for mobile networks to use the same frequencies as other services, as long as potentially interfering signals don’t rise above a certain level.
Another way to make better use of all spectrum is refarming. As carriers adopt LTE, which uses spectrum much more efficiently than earlier technologies, they plan to gradually migrate users off of their oldest networks and reuse those frequencies. Those moves ultimately will make a significant amount of additional spectrum available for high-speed data services, but it’s not an overnight solution.
“Spectrum is a scarce resource and realising economies of scale and ensuring its optimal utilisation is equally critical for both operators as well as government bodies. With more and more subscribers switching to 3G and 4G services data volumes on the networks are increasing exponentially, putting strain on the spectrum resource. Growing smartphone penetration and rise of over-the-top (OTT) services is also significantly contributing to growth of data on networks, making network economic difficult to justify in absence of adequate spectrum allocation,” says Bhanu Chaddha, Research Manager – Telecoms & Media, IDC.
He adds that spectrum auctions are rare in the Middle East and in many countries such as Saudi Arabia regulators have not been able to fully accomplish goals set under national frequency allocation plans of vacating spectrum held by government bodies and the military. “In such a scenario operators had no choice but to refarm their existing spectrum for launching next generation 4G networks. Towards this 1800 MHz spectrum has emerged as the prime candidate for refarming initiative of the regional operators for two main reasons: availability and ecosystem support.”
One is one of the reasons making spectrum refarming a compelling option for operations is the on-going deployments of 4G LTE in the region. This has been driven primarly by the embedding of LTE technology into consumer devices ranging from smartphones, laptops and tablets to femtocells, game consoles, cameras, music players and even to next-generation smart wearables and accessories.
“Wireless operator networks are faced with increasing demands for capacity nowadays, due to the proliferation of devices that rely on wireless technology, such as smartphones, tablets and laptops. The high data bandwidth can only be supported LTE technology; however, wireless operators are facing a challenge in deploying LTE due to the limited availability of spectrum. Spectrum also comes at a high cost, since it is a limited resource that can only be sold to operators by governments,” says Vick Mamlouk, VP-Wireless Sales, Commscope MEA.
In the MENA region, the spectrum availability differs from one country to another. According to Deloitte, Bahrain, the UAE and Qatar have allocated well above 100MHz of spectrum per operator, while Morocco, Egypt and Oman have less than 50MHz of spectrum per provider, which are levels comparable to India. According to the same research, the mobile industry’s spectrum holdings in the region are operationally inefficient, due to the lack of harmonization. There is also a risk that spectrum will be insufficient in the future due to changing consumer habits leading to increased data traffic.
“For governments in the Arab states, some of the options to mitigate this spectrum scarcity include releasing harmonized spectrum through the digital switchover in the Digital Dividend bands (700MHz and 800MHz), promoting spectrum liberalization by re-farming the 1,800MHz band, and promoting further release of the 2,600MHz band,” adds Mamlouk.
The biggest benefit of spectrum refarming for operators is the cost. It will be much more cost efficient to upgrade an existing network that it would be obtain new spectrum in the first place, while at the same time reducing the need for additional spectrum, which allows operators to invest in LTE technology. Furthermore, by converting the existing spectrum, the lifespan can be expanded.
While spectrum refarming has enabled operators to launch 4G services it has not be void of challenges. “Refarming is a tedious process and requires readjustment in network topology as well as base station frequencies which if not done carefully could have a detrimental effect on QoS and service experience and may as well lead to capacity constraint for existing services. It is therefore recommended that refarming is carried out in a phased approach while ensuring smooth transition between 4G and non-4G subscribes,” says Chaddha.
Mamlouk agrees: “One of the main challenges of spectrum refarming is maintaining the quality of the 3G service to customers during the LTE rollout operations. The operators must find the right balance between deploying LTE while maintaining adequate capacity in the remaining spectrum to support non-LTE traffic. Another challenge is the interoperability when between LTE and non-LTE (2G / 3G) traffic, since there are still many users in the region that use only voice services.”
