We are craving for real time data. This morning I was sitting squeezed like a sardine in the train to work and eavesdropped on a man commenting via mobile phone live on the train´s journey: “I´m leaving Bensheim (…) just passing Eberstadt (…) now arriving at Darmstadt main station.” ‘Live tracking’ can be more or less adequate. In some cases it is indispensable.
Tracking and tracing the cold chain
Live data monitoring does make sense in temperature controlled logistics. Especially when it comes down to shipping high value medication like IMPs, vaccines, APIs, biological samples or batch samples. For many years, common data loggers with USB connection have been the tool of choice in cold chain logistics. They save data locally during transit, which is then retrieved at the destination. Pitfall of those data loggers: e. g. temperature excursions are only discovered after the damage is done.
Improvements and cost-reduction in GPS (Global Positioning System) technologies in the past years gave rise to real time tracking devices. Combined with sensors to monitor temperature, humidity, light (opening) etc., they enable monitoring location, movement, temperature, humidity and light detection (which discloses whether the shipment was opened). Thus documenting regulatory compliance, preventing loss and reducing risks.
GPS real-time tracker – how do they work?
Live tracking devices are equipped with a GPS receiver. The tracking device is thus able to receive signals of various GPS satellites circling the earth. There are more than 24 working GPS satellites in total, which follow different orbits. Due to their number and arrangement, GPS devices receive signals from minimum 4 GPS satellites at a time.
Based on the period of time the GPS signal needs to travel to the GPS receiver, the latter can measure its location, movement and speed. So far, so good. But how does the data get to the recipient? Two different technologies are used to transmit data. Both drag along pros and cons.
The live tracking device using GSM (Global System for Mobile Communications) or UMTS (Universal Mobile Telecommunications System) in other words is using the mobile telephone network with a SIM card. The live tracking device sends the data to the nearest mobile mast. The mobile mast is an intermediate station that transforms the incoming radio signal into data packets that are sent via the Internet to a server (e. g. the server of the tracking device provider). From there, the logistics data is sent to the end-user who can see the temperature, humidity profile etc.
Pro: In using common mobile technology, the data transmission of a GPS GSM tracker is cheap, given country borders are not crossed. In this case roaming fees are high.
Con: The technology falls short in areas that are not covered by GSM such as in remote areas, on the sea etc.
A monitoring device using satellite networks functions slightly different. The device sends the data via satellite to a satellite relay which hence sends the data in packages via Internet to a server.
Pro: GPS satellite tracking devices make sense in remote locations and when tracking shipments across country borders.
Con: Satellite-based tracking is in general more costly than devices working on GSM basis.
Often the pros of both technologies are combined in using satellite driven tracking functions in shippings across borders and GSM based systems where GSM coverage is good.
Real time data tracking in cold chain logistics is more than a short-lived trend. It is the future. We are getting ever more used to receiving information, no matter where we are, in real time.
Thinking about it: You are familiar with Glympse? It´s an app to automatically share one´s location to others. Next time I meet the man, I´ll drop him the hint.
 Which achieves a higher data transmission rate than GSM.