Resources and Capacity Building material when explaining Spectrum

The other day we were discussing how explaining what Spectrum is can be really complicated. Conversations towards Policy and Regulation and even understanding how a device truly works can be difficult to explain because of all the technicalities are included. Could we explain it in a simpler way? Do you have any examples?

Last December we had a workshop with an Indigenous community in Puebla, Mexico. When explaining that all devices use different frequencies, we gathered all the participants in a circle and used multicoloured cotton threats to simulate the frequencies. For example, the colour orange was for the local radio. One person would be the broadcaster (he would have the tip of the orange threat) and then, another person who would represent a tower, would be connected with the broadcaster. We asked the participants “who would like to listen to the radio?” and passed along the threat, forth and back with the tower, to the ones that wanted to “listen” to the radio. Then, with another color we would simulate how it would be if someone accessed the internet from inside the community. We repeated the exercise with mobile telephony, Satellite TV and an Intranet (the participants where able to see that when accessing the Internet, the servers that save the information were outside the circle, outside their territory and in the case of the Intranet, the server was inside the circle).

Here are some photos of the exercise:


This one works great for those near urban centers: roads, with especially bus lanes.

Here is an example of a spectrum license vs shared spectrum:

Here’s an example of using multiple- or wider channels, or a frequency hog:

or even better:

Each lane is of course analogous to a channel, and each vehicle to data or packets.

It’s quite easy to compare the spectrum to lanes if you use a spectrum analyzer:

Also, to remind people that Wi-Fi is just invisible light

But it’s special in that it can go through things, so all houses look like this to it:

There are also various Wi-Fi simulators or heatmap tools

This one is called Wi-Fi Solver

What also helps is to compare it to sound, and to let people cup their ears to see how it affects what they can hear… and also to remind them that wireless point is just “an ear and a mouth”, but more specifically “a reflector and a radiator” - but that a radiator can absorb too. And that every link is a 2 way conversation.

I think the most important is to give people things that they can play with to understand vibrations and light. Even just a smartphone and a guitar can work:

Coupled with a simple oscilloscope app for a smartphone:

Or some physics experiments:

(These are also available offline on Internet-in-a-box and such.)

You can do the spectrum analyzer very cheaply with a $10 Digital TV Dongle, and apps like SDRSharp or HDSDR. I can do another post about that.

I do love the exercise with strings though :smiley: