Peter Cochrane's Blog: Smartphones, wi-fi, TV - we're swimming in a sea of radiation

But what can we make of the signals?

Woman on smartphone

Analysing signals and wireless activity can tell us a huge amount about society and how people operatePhoto: Shutterstock

Written on the Ipswich-to-London train and dispatched to via a free wi-fi hotspot in the capital at 12.5Mbps later the same day.

We all swim in a sea of radiation from radio and TV broadcasters, mobile phones, public mobile radio, walkie-talkies, games consoles, wi-fi and much more. Monitoring where the radiation hotspots are can tell us a lot about people and sections of our society.

As I travel the planet, I periodically scan the airwaves for signals and wireless activity. This habit is usually motivated by pure interest but sometimes it allows me to diagnose connectivity problems in real time. The results are always interesting, and sometimes very surprising.

To illustrate the diversity of recent scans, I have selected four very extreme examples in the 2.4GHz wi-fi band. The first is a UK retirement community, where it would appear no one is communicating.

Graphic showing wi-fi use of a retirement community of people aged over 70 years

Figure 1. A retirement community of people aged over 70 yearsImage: Peter Cochrane/

The second example is right at the other end of the age spectrum, with a cluster of teens and younger children online with a variety of devices. Here the electronic and verbal communication was intense, continuous and augmented by a lot of physical interaction through keyboards and screens.

Graphic showing wi-fi use of a cluster of young people online and communicating

Figure 2. A cluster of young people online and communicatingImage: Peter Cochrane/

The third example is a secure facility operated by a company where all communication and access was tightly controlled and monitored. Here we can see definite evidence of control. Surprisingly, it was suggested that there was no radiation on, in, or off the site.

However, I could see some activity - authorised or not - and I would guess it was for specific and specialised purposes and involved a great deal of encryption and protection.

The reality is that containing or keeping all radiation out is a really big and difficult problem. Even a Faraday cage will leak, and tinfoil is...