Monday, 2 August 2010

Interdigital's 'Fuzzy Cells' technology for cell edge performance improvement

Back in LTE World Summit 2010, I heard from Dr. Ariela Zeira, InterDigital's Vice-President of Advanced Air Interfaces about various things Interdigital have been working on.

One of the technologies that caught my attention was Fuzzy Cells technology to increase the cell edge rates. The following is from their press release for Mobile World Congress:

BARCELONA, Spain, Feb 15, 2010 (BUSINESS WIRE) -- InterDigital, Inc. today announced the demonstration of its "Fuzzy Cell" technology that improves cell-edge performance at the 2010 Mobile World Congress. The Fuzzy Cell technology is part of the company's comprehensive suite of "Next Generation Cellular" (NGC) innovations that combine advanced network topologies and spectrally-efficient air interface solutions for LTE-advanced and beyond.

"Many wireless operators and customers are experiencing a substantial degradation of service quality caused by the ever-growing demand for mobile data," said James J. Nolan, Executive Vice President, Research and Development, InterDigital. "We are at the forefront of developing solutions for more efficient wireless networks, a richer multimedia experience, and new mobile broadband capabilities that support operators to capture revenues from the boom in smartphones. The Fuzzy Cell fits nicely within our much broader efforts on spectrum optimization, cross-network connectivity and mobility, and intelligent data delivery techniques."

While cellular networks have become virtually ubiquitous, users continue to experience inconsistent and unpredictable performance when moving around. While this degradation is often the result of network congestion or an obstructed path of the radio waves, it is also inherent to traditional cellular deployments, whereby signals degrade towards the fringe of any given cell due to interference from neighboring cells. It is estimated that typical users experience this situation, known as being in the cell-edge, more than 50% of the time. Advancements in HSPA and LTE primarily increase peak data rates and only offer modest improvements in average performance throughout a cell.

Fuzzy Cells is a novel approach for leveraging existing resources to improve spectral efficiency and cell-edge performance. In a traditional deployment a device connects to one site at a time (even if multiple sub-bands are used at each site) and all sites use the same power levels and sector orientations for all sub-bands. In a Fuzzy Cell deployment, a device may connect to multiple sites at a time through the different sub-bands and continue to realize full system bandwidth. The power levels and sector orientations of the different sub-bands are optimized for best performance. In simpler terms, the device exploits the best combination of base station support regardless of its position, removing traditional limitations of cell or sector boundaries. Importantly, Fuzzy Cell technology can also allow gains indoors as it allows connection to more than one cell/sector at a time as available. The Fuzzy Cell technology provides additional improvement over Fractional Frequency Reuse (FFR) methods that are supported by current specifications.

The following shows the demonstration of Fuzzy cells:

I haven't heard any news recently on this technology but its an interesting concept, not sure if it would be adopted in the near term in the standards.

1 comment:

ksk_blog said...

An excellent example of advertising by interDigital without revealing anything as to what is really going on. If the UE is to receive data from both base-stations, who is going to perform the scheduling ? What about the backhaul requirements ? Which base station is going to optimize the power levels ? The so called "Fuzzy Cell" technology seems to be another fashionable name given by interDigital for CoMP which is well within the framework of LTE-A and is one of the items that is being standardised.