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Wireless backhaul links run either in licence-exempt bands that anyone may use within the rules, or in licensed bands where Innovation, Science and Economic Development Canada (ISED) assigns you a frequency at a specific location. Unlicensed links are faster and cheaper to set up but share the air with others. Licensed links cost more and take longer, but give you protection from interference. The right choice depends on how much the link matters and what the radio environment looks like.

What "licensed" actually means

In Canada, radio spectrum is managed by ISED. For licensed fixed links, a frequency is coordinated for your path so that other licensed users in the area do not interfere with you, and you do not interfere with them. You pay licence fees and must operate within the technical terms of the licence. In exchange, if a later user causes interference, there is a formal process to resolve it.

Licence-exempt bands, often called unlicensed, can be used by anyone with certified equipment operating within the power and technical limits set by the regulations. Nobody is guaranteed a clean channel. Your link and your neighbour's WiFi, video links and other backhaul all share the same spectrum.

Unlicensed shared spectrum your link neighbour's link same channel no protection Licensed coordinated frequency your link: frequency A other licensee: frequency B coordinated by ISED protected from interference
Shared versus coordinated spectrum. On the left, a neighbour's equipment on the same unlicensed channel adds noise at both ends of your link, and nothing obliges them to move. On the right, licensing assigns each link its own coordinated frequency at its location, so other licensed links nearby are planned not to interfere.

Spectrum rules change over time and differ between bands. Check current ISED requirements, or work with a designer who does, before committing to equipment.

Unlicensed bands

The licence-exempt bands most often used for backhaul include:

  • 5 GHz. The most common band for building-to-building links. Equipment is affordable and widely available, and range can be good. The band is also used by WiFi and many other outdoor links, so it can be crowded in cities and industrial areas.
  • 60 GHz. Very high capacity over short distances. Oxygen absorbs 60 GHz energy, which limits range and also limits interference from distant links. Well suited to short campus hops and dense urban links.
  • Other bands such as parts of the 24 GHz range are used by some equipment for short, high-capacity links.

Licensed bands

Licensed microwave links use a range of bands from a few gigahertz up to the tens of gigahertz. As a general pattern, lower bands reach further and are less affected by rain, while higher bands offer more capacity over shorter paths. Some very high bands, such as the 70 and 80 GHz range, have their own licensing arrangements that can be simpler than conventional microwave licensing; confirm the current process with ISED or your designer.

Side-by-side

FactorUnlicensedLicensed
InterferencePossible at any time; no protectionCoordinated and protected
Lead timeShort; install when equipment arrivesLonger; frequency coordination and licence approval first
Up-front costLowerHigher equipment and engineering cost
Ongoing costNo licence feesAnnual licence fees
PredictabilityCan degrade as the area gets busierStable over the life of the link
Best forShort and medium links, quick deployments, non-critical paths, backupsCritical backhaul, long paths, carrier-grade links

How to choose

Work through these questions:

  1. What happens if the link drops? If production, safety systems, security cameras or a whole site's phones depend on it, interference protection is worth paying for, or the link needs a solid backup.
  2. How busy is the spectrum? A spectrum scan at both ends shows how crowded the unlicensed bands are. A quiet rural site and a downtown rooftop are very different.
  3. How long and how fast? Long paths and high capacity requirements push toward licensed microwave or toward specific bands.
  4. How soon do you need it? If a site must be online in weeks, an unlicensed link may come first, with a licensed link following.
  5. What will the link cost over its life? Compare total cost over several years, including licence fees, not just equipment.

Whichever band you choose, the path must have clear line of sight and Fresnel zone clearance; see the Fresnel zone and line of sight.

Consider a hybrid. Many critical links pair two radios: a licensed link for guaranteed availability and an unlicensed or higher-band link for extra capacity, with the equipment failing over automatically. It is also common to back up a fibre or carrier circuit with an unlicensed wireless link.

Reducing risk on unlicensed links

  • Scan the spectrum at both ends before choosing channels
  • Use narrow-beam, high-gain antennas to reject signals from other directions
  • Design with generous fade margin
  • Choose radios that adapt modulation and can change channel
  • Monitor signal quality and set alerts for sustained drops
  • Have a backup path for anything critical

A typical case: a campus and a remote yard

Consider an organization with two needs. The first is a short link between two office buildings across a parking lot, carrying staff network traffic, with fibre between the buildings planned in a couple of years. The second is a longer link to a maintenance yard that carries security cameras, access control and the yard's only phone service.

For the short campus link, an unlicensed link is usually the sensible choice. The path is short, a 60 GHz or 5 GHz radio can carry the traffic, it can be installed quickly, and if interference appears the impact is limited and the link is temporary anyway.

The yard link is different. An outage leaves the yard without phones and cameras, and a spectrum scan at both ends shows the 5 GHz band is already busy with other outdoor links. Here the options are a licensed link, or an unlicensed primary link with a second path such as a cellular failover. The decision comes down to how long an outage can be tolerated and how the costs compare over the life of the link.

Comparing life-cycle cost

Comparing equipment prices alone tends to favour unlicensed links. A fairer comparison lists every cost over the expected life of the link:

  • Design and engineering: path survey, spectrum scan, frequency coordination and licence application for licensed links
  • Equipment: radios, antennas, mounts, surge protection and spares
  • Installation: roof or tower work, cabling, grounding, alignment and testing
  • Licence fees: annual fees for licensed links over the full term
  • Monitoring and maintenance: alarms, periodic checks, firmware updates
  • Outage cost: what an hour or a day without the link costs in lost production, security gaps or staff time, and how often an unlicensed link might be affected
  • Backup path: the cost of any cellular or second link needed to make an unlicensed design acceptable

Laid out this way, the answer is often clear. A link whose outage cost is low rarely justifies licensing; a link that keeps a whole site running often does.

How ehZee can help

Our point-to-point wireless service begins with what the link must carry and what an outage would cost you, then uses a path survey and radio environment checks to recommend a band. For the basics of how links are built, see point-to-point wireless links explained.

Common questions

Do I need a licence to use 5 GHz outdoors?

Not for licence-exempt operation with certified equipment within the regulated limits. Those limits include power and, for some parts of the band, features such as radar detection. Installers must configure equipment correctly for Canada.

Who applies for the licence?

The licence is held by the operator of the link, usually the property owner or organization. The designer or integrator normally prepares the technical details and coordination for the application.