Duke of Edinburgh supervisors and activity providers now want to provide additional safeguarding to their expeditions, in response to demands from local education authorities, and sometimes internal pressures and governance. Many have found that some of these needs can be satisfied by supplementing their existing good practice with GPS tracking technology. There are three main types of GPS tracking device; GSM, Iridium and SPOT. All have varying capabilities, and each have different costs of ownership. This is the third of three articles which discusses the merits of each. This one is about GSM trackers for D of E.
GSM devices, like SPOT and Iridium triangulate their location from satellites, but they transmit their location via mobile networks. Some transmit on 2G only, and other trackers transmit on both 2G and 3G networks. 3G networks transmit data quickly, but the range of 3G masts is only a few km, whereas 2G range can be up to 10km. Additionally, while your mobile phone might appear to have no usable signal on one given mobile network in an area, a good quality GSM tracker will still be able to function normally, as they require only a weak 2G signal to operate.
It is crucial for GSM trackers to be matched with a multi-network SIM card in order to give great performance. If instead, you were to fit a GSM tracker with a standard mobile SIM that is fixed to one mobile network, then it will be unable to transmit if you go to an area where that one network has no coverage. This is where multi-net SIMs come into play; depending on their type they will transmit on 2 or more networks, some 2G and some on 2G and 3G. It is critical to question your GSM tracker provider on the SIMs they use.
1) Does the SIM work on all mobile networks in the country where use in intended?
2) Does the SIM work abroad?
3) Does the tracker/SIM work only on 2G, or does it work on 3G as well
In terms of UK use, GSM trackers with 4-network multi-net SIMs will work in all popular expedition areas for D of E; such as the Lake District, Peak District, Dartmoor and Exmoor. There may be small gaps in coverage, but generally these are small. Only very remote areas such as the remotest areas of the Cairngorms of Scotland would get value for money from an Iridium or SPOT.
The next question come down to hardware. There are a lot of GSM trackers, and not all good. Let’s deal with those of questionable reliability and operations first. People are often tempted by a bargain; tempted to purchase a cheap tracker from an auction site or Amazon marketplace, for less than £50. These units are often advertised as Pet, child or “old person” trackers. Almost all are of Chinese origin, and the instructions that they come with make them often difficult to setup. They usually fail to meet expectation when users realise that they often are only capable of sharing their location when an SMS is sent to them, which results in a return SMS, supplying only a link to a static Google Maps view. There are some devices which provide a login to a website, where location can be viewed on a Google Maps. The reliability of these devices is usually highly intermittent. Sometimes the servers they send the data to are not available, because most are of the tracker data is sent back to servers hosted in China. Due to the nature of location-based data and protection concerns, Duke of Edinburgh supervisors should seek our the advise of a school security consultant, and check their LEA policy, to see if it is appropriate for location data about their charges to be stored outside of the EU.
If you hire or purchase your trackers from a reputable retailer, who hosts data inside of the EU, a major security obstacle is immediately addressed. Expedition Tracking GPS retailers will host the data on UK or EU-based servers, and then display that data on either Google, Openstreet Maps or Ordnance Survey Maps. Some of those map types require additional licencing which is usually covered in hire fees or may require an additional monthly premium.
Mobile data is considerably less expensive that Satellite data and so a typical monthly contract will cost under £10 per month (versus £25 – £35 for SPOT and Iridium). GSM trackers from some companies can be used on a pay as you go basis, so you only pay for months they are used, and the contract can be ‘hibernated’ for a small fee outside of those months. So a typically D of E season of should could cost the school less than £70 per tracker, which is fraction of the cost of a SPOT or Iridium over a year.
GSM trackers update far more quickly that SPOT and Iridium; typically every 90 seconds, but can be set to update as quickly as once every 15 seconds, though that is more common for fast-moving cycle events or motor sports. GSM trackers will transmit when under heavy tree cover, and often while still in buildings. They can also be remotely reset or programmed, which SPOT and Iridium cannot. GSM units have an SOS button which can be programmed to take any required action. A good vendor will usually associate the SOS button with an SMS service to multiple recipients of your choice. Each recipient will receive the SOS SMS, detailing the time and location of the GPS unit requesting help.
Garmin’s Iridium trackers are powered by inbuilt lithium batteries. Is set to update once every 2 minutes a standard 1300 Mah battery unit will last for 4-5 days. A 2000 – 2600 Mah battery-powered GSM tracker will last for 6-10 days. All GSM trackers can be recharged from mains USB, solar chargers, or power-banks, typically in less than 3 hours.
GSM trackers are the most popular choice for UK Duke of Edinburgh GPS expeditions. Schools deploy hundred every day during D of E season. The low-cost of hire or ownership makes them attractive, coupled with their fast update speeds and high reliability. The key thing to remember is not to buy into the myth that GSM trackers don’t work in remote UK areas. That is simply untrue in most cases. Always check with a vendor who retails all models, and they will tell you what is best for you.