Exploiting IEEE802.11n MIMO Technology for Cost-Effective Broadband Back-Hauling

The lack of affordable broadband Internet connectivity in rural areas, especially in emerging regions, is seen as a major barrier for access to knowledge, education or government services. In order to reduce the costs of back-hauling in rural regions, often without access to a stable power grid, alternative solutions are required to provide high-bandwidth back-hauling at minimal power consumption to allow solar-powered operation. In this paper, we show that cost-effective low-power IEEE802.11n (MIMO) hardware together with a single cross-polarized antenna can be a viable solution to the problem. Our study shows that up to 200 Mbps of actual throughput can be achieved over distances larger than 10 km while the power consumption of a typical forwarding node is well below 10 Watts (http://wiback.org/repeater) - suitable for a cost-effective solar-powered operation. Through theoretical analysis and extensive measurements we show that such a low-cost setup can be used to establish reliable long-distance links providing high-bandwidth connectivity at low latencies and consequently providing the capacity demanded by today’s services - everywhere. Exploiting these findings we are in the process of extending existing fiber-based infrastructures in rural Africa with our Wireless Back-Haul (WiBACK) architecture.

[1]  Mathias Kretschmer,et al.  Topology discovery and maintenance for heterogeneous wireless back-haul networks supporting unidirectional technologies , 2011, 2011 IEEE 10th Malaysia International Conference on Communications.

[2]  Eldad Perahia,et al.  Next Generation Wireless LANs: Throughput, Robustness, and Reliability in 802.11n , 2008 .

[3]  Kae Hsiang Kwong,et al.  Capacity and coverage analysis of rural multi-radio multi-hop network deployment using IEEE802.11n radios , 2011, 2011 IEEE 10th Malaysia International Conference on Communications.

[4]  Helmut Bölcskei,et al.  Outdoor MIMO wireless channels: models and performance prediction , 2002, IEEE Trans. Commun..

[5]  Yang Xiao,et al.  Throughput and delay limits of IEEE 802.11 , 2002, IEEE Communications Letters.

[6]  Mathias Kretschmer,et al.  Connecting the unconnected — Economic constraints and technical requirements towards a back-haul network for rural areas , 2011, 2011 IEEE GLOBECOM Workshops (GC Wkshps).

[7]  George Ghinea,et al.  A Wireless Back-Haul Architecture Supporting Dynamic Broadcast and White Space Coexistence , 2012, 2012 21st International Conference on Computer Communications and Networks (ICCCN).

[8]  David Tse,et al.  Fundamentals of Wireless Communication , 2005 .

[9]  Hsiao-Hwa Chen,et al.  IEEE 802.11n MAC frame aggregation mechanisms for next-generation high-throughput WLANs , 2008, IEEE Wireless Communications.

[10]  Saviour Zammit,et al.  Performance improvement of long distance MIMO links using cross polarized antennas , 2010, Melecon 2010 - 2010 15th IEEE Mediterranean Electrotechnical Conference.

[11]  George Ghinea,et al.  Link calibration and property estimation in self-managed wireless back-haul networks , 2012, 2012 18th Asia-Pacific Conference on Communications (APCC).

[12]  Sung-Ju Lee,et al.  Characterizing WiFi link performance in open outdoor networks , 2011, 2011 8th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks.