Tour

Let us explain how Flexihaul operates in a UHF-band scenario

The laptop on the right is acting as the basestation and the laptop on the left is the access point. Normally, the distance between these two points in a wireless backhaul link would be between 20 and 160km. The example backhaul application is a video link in this case.

The box on the top is a vector signal generator, which is transmitting a real digital TV signal captured over the air from a transmitter on Three Rock Mountain in Dublin, Ireland.

This image shows the energy associated with our digital TV transmission. We are going to move this transmission around the band to try and disrupt our backhaul link and to demonstrate how digital TV signals are detected and avoided.

This is the basestation with an additional RF front-end used for sensing and as part of the decision-making system on the right-hand side. Four channels are displayed on the screen; red indicates an occupied channel; one that we should not use, green indicates an available channel that we can use, and the channel we're currently using for our backhaul link is indicated using flashing orange.

We now change the channel that the digital TV signal is using, to interfere with our backhaul link currently using Channel 2.

The basestation detects the TV transmission. The backhaul link now changes from Channel 2 to an available channel; Channel 4.

Let's change the TV channel again. The backhaul link is using Channel 1 to begin with in this example.

At the basestation, the digital TV signal is detected and the basestation changes the backhaul link from Channel 1 to Channel 4.

And finally, taking a look at the access point on the other end of the backhaul link, you can see that the channel is now also 4 and the video link is still operating.