North Queens TV White Space Trials

     The Effects of the Technical Specifications

August 2017

On this page we will look at the effect of the technical specifications for the equipment which are influenced by regulation, what the manufactures can produce economically and our unique terrain.

For the computer predictions below we have assumed the 6Harmonics GWVS4000 radios which is type approved for the various classifications and emissions profile at the power levels shown and are the radios we used throughout these trials. The 3 classifications are

1)FCC Federal Communications Commission of the United States

2)ETSI European Telecommunications Standards Institution

3)ICSA Independent Communications Authority of South Africa

Note although FCC rules permit higher power levels to date (August 2017) manufactures have been unable to economically produce equipment capable of staying within the emissions profile.

The attached KMZ file (which opens in Google Earth) shows the predicted coverage from Tefler Hill located nearly in the middle of the community of Caledonia NS. approximately 2km from our 2nd test site where we hope to set up a community internet service.

The coverage maps assume a 30m base station antenna height and 9m at the subscribers premises and 6Mhz channel width. To get the performance we have shown the base station would have to use a 120 degree sector antennas (3 bases on different channels) and the subscribers would need a log periodic Yagi antenna with a beam width of ~30 degrees

Areas in red signal strength greater than -75dBm and in yellow greater than -85dBm

The illustrations below can be seen in greater detail in Google Earth using the KMZ file

FCC  18.5dBm +11dBi antenna	This is the maximum power permitted under FCC rules in a rural environment with this equipment 18.5dBm+11dBi antenna=29.5dBm  Under this scenario we doubt that TVWS would be economically viable for us in this location, as the tower is located in the middle of the community we can reach approximately 90 households with lower cost and faster 3.65Ghz equipment, in the areas we need coverage 3-5km out in the communities of Westfield, North & South Brookfield, Harmony and Hibernia the coverage is spotty.
ESTI Class 5	This is the power permitted under ETSI class 5 rules 25dbm plus 11dbi antenna=36dBm total , we can reach approximately 120 households (in addition to the 90 reached by 3.65Ghz equipment) This looks to be an economically viable solution.
ESTI Class 5 & ICSA Rural	This is the maximum power permitted under ESTI Class 5 and ICSA rural rules 29dBm+11dBi= 40dBm total.    We have gone from a coverage area of ~20  to ~120 square Km for very little increase in cost. As this is a remote rural region the households we can reach has only increased from ~40 to ~200 despite covering over 10 times the area, however many of them have been very expensive or impossible to reach in the past.   In our opinion this would be one of the chief benefits of this technology the ability to reach remote under served areas at reasonable cost, it does however require adequate power levels.    The question is can we do this without causing interference to others with existing equipment?

In our area we fall within the protected contour of only one channel although it is very hard to receive due to our terrain and vegetation, we did a a series of spectrum scans in May which are available here.

We note that most rule sets for TVWS have a separate classifications for rural areas, these include the Federal communications commission (FCC United States) European Telecommunications Standards Institution (ETSI) and the Independent Communications Authority of South Africa (ICSA)  

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