Projects in Wireless Technology
Many rural regions in developing and developed countries with sparse user densities do not have good connectivity solutions. To date, most networking technology solutions largely focus on urban areas of the industrialized world with high user densities.
WiFi-based Long Distance networks (WiLDNet) have emerged as low-cost alternatives to traditional connectivity solutions for rural regions. The primary cost gains arise from the use of low cost and low power single board computers, high-volume off-the-shelf 802.11 wireless cards originally intended for industrialized markets and low cost towers. Unlike mesh networks, which use omni-directional antennas to cater to short ranges (less than 1-2 km at most), WiLD networks are comprised of point-to-point wireless links that use high-gain directional antennas (e.g. 24 dBi, 8 deg beam-width) with line of sight (LOS) over long distances (10-100 km).
The TIER research group at UC Berkeley developed novel TDMA-based technology to achieve high performance from long-distance wireless links at very low costs. This technology has been deployed in several developing countries and tested to provide reliable performance at very long distances (including the current world record of 382km for the longest unamplified 2.4 GHz WiFi link in Venezuela).
One of the key successes of this technology has been the partnership with Aravind Eye Hospitals in India to connect remote, more than ten rural eye clinics to major urban hospitals using high-bandwidth long distance links. These clinics offer remote consultation services with doctors from Aravind hospitals in an effort to extend the reach of the eye-care services to remote rural areas. In the first two years of operation, the network has already enabled over 100,000 remote patient-doctor consultations and has led to the restoration of vision for more than 20,000 of these patients, leading to new economic opportunities for them. In addition, most of the eye clinics have also achieved operation sustainability. As a result of this initial success, Aravind is planning to extend their network to 50 such centers in the following years to cover more than 500,000 people.
De Novo group is now extending the TIER research work to offer a complete long-distance backhaul solution for the 5.8 GHz spectrum that combines full-duplex and half-duplex TDMA operation with reliable throughput of 50 Mbps (that can be scaled up to 150 Mbps with three parallel links) at distances as long as 100 km. The solution can also be easily extended to work multiple hops by incorporating optimal frequency reuse. We also provide user-friendly remote administration and monitoring tools.
Please click here for more information on our solution. If you are interested in deploying our solution or partnering with us to implement a project, please contact us or email us directly.
To learn more about the research behind our technology, please read our overview paper, Rethinking Wireless in the Developing World presented in Hotnets V, 2006. To understand more about how we achieved sustainability in the Aravind Eye Hospitals project, please read our paper in IEEE Computer, 2008. The full list of other technical papers describing our technologies is available here.