Unlicensed Frequencies - If 5GHz Safe?
These solutions are popular as they will only have the initial CAPEX expenditure and the only OPEX would be ongoing support which is typically an optional requirement. There's also a lot of throughput to be gained using these unlicensed frequencies with some manufactures boasting up to 876Mbps raw throughput.
When looking for a wireless bridge or a point to multipoint solution in the unlicensed frequency ranges it is advised that the 5GHz spectrum be used. 2.4GHz has become saturated over the years, with only three usable channels it leaves itself open to interference from many other 2.4GHz networks and products in the surrounding areas. 5GHz will have many more usable channels at its disposal which is less prone to interference however if you are looking to install your bridge in a built-up area whether residential, industrial, town or city centre careful planning is needed. It is not enough to have line of site and good mounting positions as 5GHz is now widely used and built up areas are becoming more and more crowded. Some decent solutions will have analysis tools built into the GUI (Graphical User Interface) however for untrained engineers it is highly recommended that a thorough professional survey be completed or at least advice is sought before a purchase is made. If you choose a professional survey this will give valuable information that will potentially save money in the long run by arming you with the knowledge needed to make an informed decision on which solution will work for you.
If you find the area is saturated and an unlicensed solution cannot be used a licenced solution will be required. 70Ghz and 80Ghz licenced products are becoming more common place as these frequencies only require a lite licence to use. These are typically in the enterprise to carrier class budget brackets however if the link is critical for you or for your business it will be worth the additional cost and the piece of mind.
For further information on the 5GHz frequencies part one of the follow blog written by Darren Gauntlett will prove very useful: 5GHz Frequencies