North Queens TV White Space Trials




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October 2017


When we originally applied to CIRA for assistance in conducting these trials we had hoped that the Canadian TVWS regulations would be final and a database administrator would have been appointed so we could run the trials under the final operating conditions faced by any operator.


Currently (October 2017) The technical specifications for the equipment are under review and open for consultations and Key Bridge have a data base under development with certification pending.


In both the United States and the United Kingdom regulations have been en-acted for some while we don't know the reason for the delay in Canada but perhaps it has something to do with the understandable desire to harmonise regulations with the United States along the border but at the same time have a set of regulations that take into account rural Canada's unique requirements.


Our tests have shown that in rural areas we need a link loss budget of at least 125dB with a noise floor of around -100dBm and a SNR of 25dBm this means the received power needs to be about -75dBm

If the link loss is 125dB then the ERP would have to be 50dBm to maintain a decent link margin.

 The current proposed limited of 36dBm will make it very hard for operators to get the job done cost effectively in remote rural areas, it may be fine for urban areas with higher population densities, the old RBS rules were more flexible in this regard.

 We think a blended approach could work well with the current proposed rules for urban areas and those very close to the the border and some changes along the lines of the old RBS rules for other areas, the main changes being......


1)The introduction of a 2nd class of fixed TVWS device with a more relaxed emission profile,to reduce the possibility of these devices causing interference they would not be permitted to operate adjacent to an active TV channel but would have to maintain a separation of at least one channel, the exact separation and maximum power level permitted could automatically be handle by the data base administrator interface.

2) An increase in the maximum allowable ERP particularly for point to point links where the chances of causing interference could be minimised.

3) An increase in the maximum allowable antenna height.


These changes could apply to specific areas, be on a case by case basis or through the data base administrator.


We also understand ISED are working on rules to permit channel bonding as permitted in other jurisdictions, if these could be extended to more that 2 channels it would greatly increase the data throughput available per radio and reduce costs. The CRTC have recently come up with a goal of 50Mbs for all Canadians this would be very hard to achieve with the present 6Mhz channel widths.