Graeme Blick gave us his Viewpoint tonight. He said ...
'We live in an age where we have all seen huge technological advances from the
- introduction of television
- the use of the PC; and
- the introduction of cell phones and smartphones
'For my part, for the past thirty years I have been involved in and seen the development and wide adoption of the US Global Positioning System, or as we know it, GPS.
'However GPS is just one of a number of Global Navigation Satellite Systems (GNSS) with the Europeans, Chinese, and Russians also now having fully operational systems in addition to GPS. These navigation systems use constellations of satellites orbiting at over 20,000 kms (the international space station orbits at about 400km), travelling at about 4km/second, and have a low transmitted power output of about 45 Watts – the power of a small light bulb.
'Such systems allow us to position ourselves in real-time to an accuracy of about 10m using a smartphone or car navigation system. I recently tallied up and we had seven such devices that used GNSS at home.
'We can also use this technology with more sophisticated receivers and in a differential mode to make precise measurements – for example for measuring plate tectonic motions at the mm level – i.e. tectonic plates that move at a similar speed at which your finger nails grow!
'However, what is not so widely known it that GNSS systems give us the ability to access precise timing (at the picosecond level – 0.000000001") easily and cheaply (chips worth tens to thousands of dollars) – something that otherwise would need atomic clocks worth many hundreds of thousands of dollars. Precise timing is used in many applications that we rely on in our everyday lives, e.g.
- for our computer networks and internet
- in the telecommunications industry for satellite TV and communications
- in cell phone networks
- in the power industry for switching; and
- in the finance industry when we make electronic financial transactions and use ATM machines
'GNSS has now become a ubiquitous technology that has permeated our everyday lives. And yet we receive these signals from space for free but have no (or little) control over their delivery, accuracy, or integrity. Added to this is the fact that GNSS signals are very weak and are susceptible to disruption and interference. This disruption can come from
- natural events such as solar storms
- unintentionally through the use of devices using radio frequencies close to GNSS frequencies
- or intentionally through the use of jammers – these can be easily made or brought for as little as $30 through the internet
'A recent example of the impact of using a jammer in the US was when a truck driver used a jammer in his truck so that the trucking company could not track him at lunchtime when he visited his girlfriend. Unfortunately, his girlfriend lived near a major airport, and when he turned on his jammer not only did he deny the trucking company access to his position but he also disrupted the navigational aids at the airport – essentially shutting down the airport.
'So my point of view is that technology can assist us in many ways in our everyday lives and bring tremendous benefits but we need to be aware of the risks of adopting these technologies that we have little or no control over. We must ensure that we have back-up systems in place or measures to mitigate any disruptions to services. Otherwise, we put ourselves at huge risk and potential cost should these technologies fail or be disrupted, either unintentionally or intentionally'.