“Good” Engineering

In the spirit of using the unlicensed bands, our project must coexist with existing users and other entities outside of the project making use of the 2.4GHz ISM band. Our project and its users are to do their due diligence in the name of good engineering to coexist with others users of the 2.4GHz spectrum.

_ Before you read any further into this post, we are not lawyers, and Canada
/ ! \ regulations are hard to parse and sometimes harder to find with the
—- current state of the Canadian Government’s website. Please do your
own research and confirm this data before following it. This is just a best attempt at finding and reading the regulations that may apply to our research project ISM band use.

According to the government webpage, https://www.ic.gc.ca/eic/site/smt-gst.nsf/eng/sf10971.html#s5.4, the maximum EIRP limit for fixed point to point network devices shall not exceed four watts and non-fixed point devices shall not exceed one watt. This our best attempt to find the regulations for our use case. Do your part to observe power limits and other regulations.

As with any project, the radios you place into operation should been done observing your best effort at good engineering. Minimize chances of possible interference to existing systems, aim your radio’s beam towards the node you wish to link with, and use the least possible transmitter power to make a stable connection. At the end of the day, is on you (the network user) to make sure your equipment meets Canadian standards and is operated acceptably.

Just for example, if you were to use the same radio that the project officially uses (UBNT NanoStation LOCO M2), than the highest calculated EIRP for a mobile node would be 30dBm including antenna gain. The highest power level you could select in the firmware would be 22dBm due to the radio’s internal antenna having a gain of 8dBi. (22 dBm + 8dBi = 30dBm = 1 Watt RF Power)

RSS-247 – Section 5.4.b – 2400-2483.5MHz Band Regulations

For FHSs operating in the band 2400-2483.5 MHz, the maximum peak conducted output power shall not exceed 1.0 W if the hopset uses 75 or more hopping channels; the maximum peak conducted output power shall not exceed 0.125 W if the hopset uses less than 75 hopping channels.  The e.i.r.p. shall not exceed 4 W, except as provided in section 5.4(e).

RSS-247 – Section 5.4.e – 2400-2483.5MHz Band Regulations

Fixed point-to-point systems in the bands 2400-2483.5 MHz and 5725-5850 MHz are permitted to have an e.i.r.p. higher than 4 W provided that the higher e.i.r.p. is achieved by employing higher gain directional antennas and not higher transmitter output powers. Point-to-multipoint systems, omnidirectional applications and multiple co-located transmitters transmitting the same information are prohibited from exceeding an e.i.r.p. of 4 W.

Now That That is Out of The Way…

If you are placing a portable station into operation, make sure that you have the permission of the location you are using to be there, don’t let your equipment get into the way of others, all that good stuff.

If you are placing a fixed station into operation, make sure (if applicable) that you properly ground the setup and take proper precautions to operate your station safely. We live in a region that has very common cloud-to-ground lightning. Don’t become a statistic and make sure you do things safely. Outdoor wifi equipment makes usually offer options for POE injectors that provide built in safety grounds and some offer surge suppression. If you are operating a fixed station, these may be good options to seek out for safety.

This is Just A Document of Tips

This webpage is just a collection of useful information and tips. At the end of the day, it is your (the network user) responsibility to operate your station legally and safely.