OTTAWA – A year after the U.S. Federal Communications Commission (FCC) issued final rules for the use of spectrum white spaces, Industry Canada has begun its own process to deal with the unassigned spectrum.
The department’s goal, in SMSE-012-11, is to develop a technical and policy framework to make additional spectrum in the TV white spaces spectrum below 698 MHz available for licence-exempt applications. White spaces are portion of the TV broadcast spectrum that are unassigned to prevent interference between stations or are in limited demand. Consumer and other products designed to operate in the white space spectrum are expected to hit the U.S. market later this year or early next.
The consultation is seeking comments on a number of elements including the types of devices (fixed and mobile); the TV channels in which to allow devices to operate; the protection of existing TV broadcasting; white spaces and rural remote broadband systems (RRBS); the impact on low-power apparatus such as wireless microphones; and others.
With respect to RRBS, Industry Canada has already licensed broadband systems using this unassigned TV spectrum (it first decided this back in 2006 with final rules published about 18 months ago) and now it has to decide whether to stick with the status quo or shift to a new approach. The current licensing hasn’t been without its challenges due to the lack of equipment economies of scale resulting from the small Canadian market. Still, the department has licensed 555 RRBS operations across the country.
A new approach being considered would be a licence-exempt regime for RRBS.
“In this case, RRBS would be phased out in favour of white space devices. In order to ensure that there is no loss of functionality or coverage compared to existing systems, the technical rules for white space devices would be relaxed (e.g. to allow for increased power), under database control, when they are operating in remote rural areas,” states the consultation document.
On the broadcasting front, the department notes there will continue to be analog TV after the August 31 digital transition deadline and therefore requires interference protection. To do this, broadcasting stations and white space equipment require a physical separation. But Industry Canada says the UK regulator Ofcom is using an alternative approach that could offer greater opportunities for the Canadian market.
“Rather than specify minimum separation distances, Ofcom has proposed that white space devices in the United Kingdom continuously adjust their transmitter power levels under database control to ensure that TV broadcast interference protection requirements are met,” notes the department.
This added flexibility, says Industry Canada, could “increase the amount of spectrum available to white space devices without any increased risk to TV broadcast reception.”
Allowing the use of white spaces in Canada will also have an impact on low-power apparatus (LPA). The most well-known are wireless microphones, but the band is also used for cue and control communications and synchronization of video camera signals.
In the U.S., the FCC has identified two channels (12 MHz total) in each market across the country. Industry Canada is considering this approach because the spectrum wouldn’t be shared with white spaces, and therefore “would ease sharing between broadcasting and LPA and would allow for rapid LPA deployment without the need to first register such devices.”
Industry Canada suggests that a number of different devices operating in the TV white spaces could be introduced to the Canadian market, including consumer Wi-Fi devices with a significantly longer range, lower cost broadband equipment and innovative products and services. New applications could emerge as well such as last mile wireless Internet access to households and local area networking within the home.
The consultation is also giving the department an opportunity to consider using a new method of controlling interference between licence-exempt devices and those in adjacent bands. Industry Canada suggests that registration databases could “allow for real time control of interference” and enable changes to technical and operating requirements on the fly.
“For example, interference protection criteria could be tightened or relaxed, as required, as experience is gained. In addition, operation of malfunctioning equipment could be immediately restricted until it is possible to make necessary repairs,” reads SMSE-012-11.
Comments on the proposals made in the consultation are due November 4 with reply comments by December 2.
