The Singapore White Spaces Pilot Group (SWSPG) and founding members the Institute for Infocomm Research (I²R), Microsoft, and StarHub earlier this month announced the first commercial pilot deployments of TV White Spaces (TVWS) technology in Singapore. TVWS refers to the unused VHF and UHF frequency spectrum in the TV broadcast bands, and which is being used to deliver wireless broadband connectivity. Because TVWS belongs to the lower frequency bands, it comes with inherent lower-power and longer-range characteristics. Alluding to its data-centric focus, the technology is also being referred to as Super Wi-Fi.
How Super Wi-Fi works
Based on documentation that I obtained, Super Wi-Fi offers 400 meters of coverage compared to the 100 meters of traditional Wi-Fi. This works out to an impressive 16 times the area covered and the same amount of power used. The application of TVWS for data backhaul and use as a long-ranged Wi-Fi application are being studied. Super Wi-Fi Up allows up to 14 Mbps to be delivered on one 8 MHz channel; a range of 1.2km was demonstrated in a downtown area in Singapore.
The longer range and ability of Super Wi-Fi to penetrate walls means that bandwidth has to be allocated properly. Location-aware, radio-enabled devices have to first check with an online database to determine the available channels and power level permitted at a current location. Available spectrum is dynamically allocated to deliver low-cost broadband access and other forms of connectivity to consumers with the minimum interference (Figure A).
Image source Microsoft
Details about the pilot projects
Three pilot projects have been deployed. Here’s a summary of each project:
- In partnership with the Singapore Island Country Club, Microsoft and Neul are leveraging TVWS to link various sites at the club. This is used in tandem with aging Asymmetric Digital Subscriber Line (ADSL) infrastructure to provide a reliable and alternative means of Internet connectivity. Possible expansion of this deployment includes using it to remove Wi-Fi blind spots in the current club houses and providing Wi-Fi coverage on its four 18-hole golf courses.
- StarHub is conducting a marine Wi-Fi pilot project in partnership with I²R, Microsoft, Neul, and Adaptrum. This is currently being carried out in Changi, with measurements conducted from designated boats that can travel up to 10km away from the shoreline.
- I²R is partnering with Power Automation Pte Ltd on a pilot project to develop a TVWS-based platform for utility providers to remotely control and manage utility meters in a cost-effective manner. An Advanced Metering Infrastructure (AMI) system based on TVWS is being deployed in NUS University Town as a pilot project, offering long-range wireless communication of up to 1km.
What this means for IT professionals
This technology has implications for rural deployments where traditional backhaul methods may be expensive (satellite) or may not exist (cable); it can also be used to complement existing wireless services to cover blind spots that may be difficult to reach with Wi-Fi.
The different frequency band being used — 600 Mhz vs. 2.4GHz or 5GHz — makes it possible for a house or building to deploy Super Wi-Fi and traditional Wi-Fi. For example, Super Wi-Fi could be used to bridge between the farthest parts of a house or office environment, while more traditional 802.11a/b/g/n Wi-Fi is used to furnish actual wireless coverage.
Though it may be a while before the technology becomes widely available, TVWS or Super Wi-Fi is probably a technology worth keeping an eye on.