Mobile Signals Could Get A Boost From Femtocell Networks
January 26, 2013

Befemto Project Could Lead To Improved Cell Phone Signals

redOrbit Staff & Wire Reports - Your Universe Online

The “dead zones” or “black holes” that can sometimes cause mobile phones to lose their signal may soon be a thing of the past, thanks to the efforts of European researchers who are exploring new forms of telecommunication technology that could ultimately improve connectivity and coverage at the local level.

“We live in a 24/7, always-on, mobile and wireless world. Wherever we go we are connected - to each other, to the web, to all our favorite apps, to whatever data we need, exactly when we need it. Or so we like to think,” the European Union´s Community Research and Development Information Service (CORDIS) explained in a statement Friday.

“The reality is quite different,” they added. “There are corners of our homes where the web won´t work. There are black spots in towns and huge holes in the wireless network in more remote areas. Coverage is far from complete. To compound the problem, even when they have a good signal, smartphones often struggle to download the data they need because the mobile networks are saturated. The airwaves are at full capacity.”

To help address the issue, researchers are working on next-gen, miniature mobile telephony cells known as femtocells, which CORDIS claims will improve both connectivity and coverage area. Femtocells are localized cells that essentially replace long-range base stations, and instead of trying to cover vast areas, they are more focused, improving cellphone coverage for a single home or office, or for a handful of buildings.

“A commercial small cell might boost mobile connectivity for a whole office while a mobile femtocell could provide passengers on public transport with a strong and static signal (sparing their battery and eradicating sudden drops in signal),” the statement said. “Femtocells are far more than mobile booster stations; they can also help to divert data traffic off the mobile airwaves. This offloading creates more network capacity.”

When they are wired into fixed-line broadband networks, femtocells are capable of rerouting data and voice traffic across wires, thus freeing up spectrum for additional cellphone traffic. However, the devices are still in the idea stage, and there are many bugs to work out, according to CORDIS.

For instance, researchers need to figure out a way to keep femtocell signals from interfering with main base station signals. These issues are why several telecommunications experts, research and development organizations, mobile operators, and other industry giants have teamed up to develop functional prototype femtocells as part of the Broadband-Evolved Femto Networks (Befemto) project.

“Europe recognizes that mobile connectivity is a powerful social and economic driver,” project coordinator Dr. Thierry Lestable said. “EU support for the development of cheap technologies to enhance and boost innovative services is really important for growth, not just growth for telecoms manufacturers and providers, but for the entire economy. Most businesses rely now on mobility and permanent connectivity.”

“By adding femtocells and small cells into the mobile network mix we make it possible for mobile operators to improve their spectrum efficiencies through heterogeneous networks (HetNets) and seamless integration of the fixed line telecoms network,” he added. “But this rerouting has to be optimized and intelligent. We have been developing and testing self-managed femtocell connections which are programmed to pick their wireless protocols and frequencies and route traffic depending on a whole host of contextual data.”

Through the Befemto project, researchers have developed artificial intelligence which allows the femtocells to alternate between using radio frequencies and fixed broadband networks based on the amount of traffic present at a given time. They are also able to communicate with base stations without interference and without harming that station´s capacity or signal quality, the researchers explained.

“These new algorithms allow femtocell networks to work together to provide top quality coverage for users and support seamless, low-power and low-cost relief enhancement to the mobile service,” said Dr Lestable. “We are focusing on the newly launched LTE or 4G networks because customers are paying a premium for these and will expect a true broadband experience: fast, reliable and unlimited access to everything everywhere. Femtocells, and small cells will allow operators to meet these expectations and lower their operational costs at the same time.”

Thus far, members of the Befemto project have applied for a dozen patents, ranging from network monitoring software to mobile traffic optimization algorithms, CORDIS said. They have also made 27 direct contributions to 3GPP, the international standards organization that governs mobile technology, and have published more than 70 papers worldwide describing their findings to date.

“The Befemto technologies and system architectures have been tested in five pilot demonstrations,” the statement said. “Trial results show that femtocells significantly reduce load on mobile networks while boosting signal strength and quality at a local level. The work of the project will support mobile operators to reach two major technical targets: high spectral efficiency (8 bits/s/Hz per cell) — meaning more and better use of scarce airwaves — and a maximum mean transmit power of 10 mW — for lower levels of interference.”

“Most importantly, our trials also prove to mobile network operators that the small cell model is a good one,” the project leader added. “We've looked at several different business models for their deployment; no matter which one you follow, femto- and small cells will save mobile operators money and help them to create value — a sure way to get them to market.”