Mathematical analysis reveals how to maximize access to mobile networks by seamlessly ‘offloading’ traffic to smaller Wi-Fi and cellular systems
Data-intense multimedia applications are stretching cellular network capacities to their limits, but A*STAR researchers have developed a strategy to ease this burden using ‘data offloading’1. By using high-level computational algorithms to investigate data transfer between cellular base stations and ‘complementary’ setups such as home Wi-Fi systems, the team identified optimal ways to satisfy user demands across multiple, heterogeneous networks.
Wi-Fi networks and small, low-power femtocell and picocell cellular antennas are inexpensive, simple to install, and highly compatible with existing smartphones and tablets. For these reasons, mobile operators consider data offloading to these complementary networks as a more feasible way to expand capacity than installing obtrusive infrastructure or bidding for new frequency spectra.
Chin Keong Ho and Sumei Sun from the A*STAR Institute of Infocomm Research in Singapore and colleagues probed one of the biggest obstacles for implementing this sharing technique: deciding when and how much data to offload from the primary network. “Many parameters, such as user requirements and cellular coverage, can affect the real-time performance of the base station,” says Ho. “The dynamics of network and user traffic make optimal offloading decisions very challenging.”
Ho notes that the loads, or demand for cellular service, of networks using data offloading are coupled through complex, nonlinear relationships. For example, increasing the load on one base station can produce interference with another base station. To maintain the same quality of service, the second base station may have to increase its load or power — subtle changes that can ripple through the combined Wi-Fi and cellular networks.
To resolve these problems, the team developed a simple but accurate model to describe a network of base stations that can interfere with each other and a series of complementary cells that can accept excess data. They then employed advanced mathematical tools to produce a load-coupled equation that characterized and optimized the data-sharing network in detail.
As a result, the team could suggest potential strategies. “One interesting finding is that for certain networks, it is impossible to satisfy user demands no matter how large the powers of the base stations,” says Ho. “Consequently, data offloading is the only means to serve the users — a finding that highlights the fundamental importance of this approach.”
The researchers believe that their load-coupling model could find practical use by determining the optimal number of small cells or Wi-Fi access points in an offloading system. Furthermore, their equations could ‘future-proof’ mobile networks by analyzing performance degradation as user requirements inevitably change.
The A*STAR-affiliated researchers contributing to this research are from the Institute for Infocomm Research
Ho, C. K., Yuan, D. & Sun, S. Data offloading in load coupled networks: A utility maximization framework. IEEE Transactions on Wireless Communications 13, 1921–1931 (2014). | article
Study suggests buried Internet infrastructure at risk as sea levels rise
18.07.2018 | University of Wisconsin-Madison
Microscopic trampoline may help create networks of quantum computers
17.07.2018 | University of Colorado at Boulder
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Materials Sciences
18.07.2018 | Health and Medicine