Past and minor Involvements

Sunday, August 01, 2010

Idea: Building in mobile phone beacon technology to help search and rescue operations

Telcoms infrastructure is often down or saturated during a disaster, however even if a mobile device cannot be used to dial a call or send an SMS, they inherently have another capability. Mobile devices are effectively radio transmitters that with very little modification should be able to act as locating beacons to locate trapped people in the locality of say about  within a 200-500m radius.

Mobile phones are quite pervasive now with high penetration even in developing nations . These days most people carry a mobile phone wherever they go.  During my visit to Taiwan, I got an opportunity to speak to a leading OEM chip chip manufacturer, who’s chip functionally ends up in a great amount of phones today and they informed that this very doable. 

Please do not confuse this with locating mobile phone using cell towner triangulation techniques as that lacks the granularity to locate people in for example a trapped building block. With this you should be able to say the number of phone in for example a collapsed building and make a guess at the amount of people trapped. The natural attenuation of the signal also should help build a suitable “metal detector” like tool to direct a search and rescue operation to the mobile phone and the trapped people or bodies with them.

You might also counter saying that GPS technology can be a better locator, however GPS technology requires a clear line of sight and even to SMS their location it all requires active input by a potentially unconscious person and a level of literacy on mobile functionality beyond the basics.  If anything the only input required would be to say someone is OK, so that their signal no longer contributes to the noise of multitudes of signals of the number of people with mobile phone in say a 500m radius. Or they might annotate their signal with a request for urgent help or with other information if they so wish, but that would be optional. One issue is battery consumption as most of the time mobile phones are not transmitting, but are passive receivers which require consumes far less battery power. Transmitting a beacon will have to be done in very energy efficiently way. Like a periodic beep and powered for say a maximum range of 500m.

Yes you might worry about privacy or abuse in non-disaster times, in people being able to locate you, and there should be a way for the user to turn it off when needed or it is something that is turned on only on a cell broadcast by a tower. Detectors, which would be specialist directional devices that can locate people with such granularity has to be restricted to emergency use though legislation.

Additionally in more advanced phones you might be able to use it as simple short range walkie talkie to permit those that are trapped to communicate with the rescuers and broadcast a help message.

I am going to follow up on this possibility, which I thing will have a significant impact for search and rescue. Thoughts?