Do I want a connected or disconnected GPS system?
1 Feb 2010 Jason 2
Last time we talked about the basics of GPS is and how it works. There are many different uses for GPS systems from farming to aviation and everything in between.
One sector that benefits heavily from GPS is ground transportation. Whether you’re getting your kids to an out-of-town soccer game or you’re moving hazardous chemicals interstate, GPS navigation systems for ground transport can make the journey faster, more economical and safer for everyone.
But there are two distinct flavors of GPS devices and your navigation needs will determine which you should choose:
- Connected – A connected GPS receiver uses its built-in connectivity (either GSM/GPRS or CDMA – GPRS is preferred and is more suitable for live tracking) to connect to a wireless provider (e.g. Sprint). This allows it to communicate information such as its location, altitude or speed to other devices or a web browser application, such as this program. An example of this is Telogis Fleet, which helps fleet owners manage multiple GPS receivers (which could be in cars, trucks, vans or even attached to people).
- Disconnected – A GPS device that is disconnected only receives signals from the free GPS satellite network, or constellation as it’s called. Information such as current location, speed, altitude and time is only available to the user of the GPS device. Unlike a connected GPS receiver it cannot send or transmit data to another device. The units are often cheaper because they do not have any built-in connectivity.
What are the differences between a connected GPS system and a disconnected one?
Whether you choose a connected or disconnected GPS navigation system really depends on what your needs are. Let’s review the features of each system to help you decide.
Connected GPS System Disconnected GPS System Pros
- Send data – Information can be sent to other devices including to a network such as the internet, allowing effective management of deployed GPS devices.
- Receive from other devices – While all GPS units receive data from the satellite constellation, only connected GPS units can receive data from other terrestrial (earth-based) devices including internet browsers, which can add functionality to the GPS receiver. This may include live route changes from a central command unit or task updating from a supervisor.
- Monitor remote or harsh locations – Unmanned GPS devices can send data to an operator many thousands of miles away. This can be used in situations where a GPS device is monitoring a weather balloon, tectonic plates, wave buoys or a parked trailer unit.
- Increased safety – Interested parties can be alerted to predefined exceptions such as when a GPS device strays outside a perimeter or exceeds a speed restriction. For example, some parents subscribe to Verizon’s Family Locator service which can be setup to alert them when their child leaves a specific location such as school or a friend’s house.
- It’s free – No surprises here. While deploying and maintaining a network of satellites costs billions of dollars, the U.S. military kindly made it available to the general public for free. What this means is that all you need is a GPS-enabled device, like a mobile phone or a Garmin in-car unit, and you can start accessing location data right away. No monthly fees required!
- It’s accurate – While a connected device offers the same degree of accuracy, to know you can get location data accurate to within a few meters for free is good value in anyone’s books. Of course, it’s not as accurate as the location data used by military or commercial devices, which enjoy pinpoint accuracy but it’s still accurate enough to make sure you don’t get lost, no matter where you are.
- Built-in applications – Many GPS-enabled devices come preloaded with city or country maps and POI (Point of Interest) data that can allow a user to start using navigation features right out of the box. Of course, this data can become outdated in which case you might need to pay for an upgrade.
Cons Cost – Unlike the free access GPS receivers have to the satellites, because a connected unit accesses a wireless carrier’s network data charges usually apply. While costs will vary depending on which carrier you connect to and how much data you send and receive using the connection, an example from Verizon Wireless lists a monthly charge of $10 for the Navigator product which provides turn-by-turn directions for travelers. Limited – Because the unit can only receive, the data is only available to the user so it cannot be used by any third party, limiting its usefulness. Due to their traditionally small size, devices are often limited in processing power and storage capacity, which can lead to a lack of functionality and ability to store historical data.
So which do I choose – connected or disconnected?
When you’re shopping for a GPS navigation system, you need to step back and see the bigger picture. If you only need it to find your way in and out of the woods, then a disconnected device will probably be all you need.
On the other hand, if you need extended functionality, turn-by-turn directions, location information, provide interested parties with details of your location or have to manage several vehicles or workers on the move then you’ll need connected devices. Make sure you check you’re getting the right hardware for your needs and, if you are investing in commercial fleet management software, check with your vendor for details on what hardware they recommend. For example, Telogis list their recommended hardware suppliers for fleet owners purchasing the necessary GPS hardware.
In our next post, we’ll talk about finding the best GPS system for your ground transportation needs using connected devices.