Wireless, Antennas, and your AvaLAN EMV Solution: A Brief Briefing
The In-Dispenser Subscriber Units (IDSUs) and the In-Store Access Point (AP) are installed, you’ve just finished pairing the units, and now your site is up and running. In some way, that metal box with antennas in your dispenser is talking to that metal box that also has antennas hanging on the wall inside the store.
The AvaLAN Wireless EMV devices use radio waves, generated by a current flowing through an antenna, to send data through the air. The AvaLAN Wireless EMV Solution uses omnidirectional antennas, a type of antenna that emits waves in a shape most easily described as a donut – sending them out in all directions around the antenna except for the area immediately above and below. As these waves propagate outward different things can happen to them, namely:
Attenuation: loss of power; most commonly through distance
Reflection: when a wave hits a smooth object larger than itself, it will reflect
Scattering: if a wave is larger than the pieces of whatever medium it passes through are, it will scatter the signal (this can happen with certain tints on windows)
Refraction: if a wave passes through a medium with a different density than the original medium, it causes the wave to bend.
Diffraction: when a wave hits an object and bends around it
Absorption: if a signal does not bounce, reflect, or bend around an object it gets absorbed
Thus, in order to obtain the best signal, all IDSUs and APs should have their antennas parallel to one another. It is generally best practice to have your AP in line-of-sight with your IDSUs when possible, but not in every situation. It may be better to mount the AP on a nearby wall instead of the window if there is solar coating over it. The solar coating can cause the wave to scatter, as mentioned above, and will result in a much poorer signal than if the wave only had to pass through the external store wall.
Here we have properly mounted AP and IDSU, with both units having their antennas parallel - pointed up and are roughly on the same plane. If the IDSU was just laid in the dispenser, the signal quality would be noticeably worse. We recommend mounting the IDSU like so – do not just lay it down in the dispenser!
If you are using our external antenna, things are slightly different. The antenna should be mounted similarly to the example here, keeping the donut shape in mind. The AP can be mounted inside anywhere, as long as the 8ft cable to the external antenna can reach it.
As always, our support team is ready and willing to answer any questions you may have regarding our product and proper installation methods. Give us a call at 650-384-0000.