The Antenna Dilemma

By Amanda Kowalik   June 8, 2016

Choosing a sector antenna seems simple. Just look at the gain, frequency range, and beam width. Right? Well, unfortunately not. There are a few other factors to consider that, if ignored, can leave your network limping and your customers complaining. Let’s take a look at three of these factors.

First, the gain. This may seem like a very simple figure – what is the gain of the antenna? But what many antennas fail to do is keep consistent gain across their supported frequency range, at times even between channels in the same frequency band. Unless you were to test the antenna before installation (and let’s face it, who has time for that or a spare testing chamber lying around) your network could have dramatically reduced range just because you picked the “wrong” channel.

Second, nulls. Nulls can occur at varying distances from the antenna, and are points at which the signal from the antenna is very low, stopping you from providing service to customers caught in them. The tricky part about nulls is they are sometimes counterintuitive – occurring closer to the antenna rather than further away. This puts you in the confusing situation of being unable to provide service to customers closer to your tower, when you can still connect those further away!

Third, the front-to-back ratio of the antenna. This is an important aspect of any antenna used in a frequency reuse deployment, as a poor front-to-back ratio (less than 30 dB) means your network will interfere with itself, limiting its performance. But another side to this is the angle behind the antenna over which this front-to-back ratio is achieved. Many antennas with a good front-to-back ratio achieve it only in a small angle directly behind the antenna, which means they still generate enough interference to be harmful to the rest of your network.

What makes a good sector antenna, in light of these problems? One that has consistent gain across its frequency range, good null fill, and a great front-to-back ratio in a wide angle behind the antenna, not just in the center.

The 90/120° Sector Antenna from Cambium Networks is engineered and built to meet these demanding requirements, giving you the carrier-class performance you need at a fraction of the usual cost. And with a compact design and integrated ePMP mounting, installation is easier than ever before.

For more information on what makes a good sector antenna, check out the video here:

For more information on the 90/120° Sector Antenna, download the specifications here: 

And for some background information on front-to-back ratio, watch the video here: