How Does GPS Actually Work?
Ever wondered how a small chip in a tracker or phone knows exactly where it is on the planet? It's not magic, and it's not quite what most people assume either.
GPS satellites constantly broadcast the time and their own position. Your receiver picks up signals from several satellites at once and calculates how long each signal took to arrive. Since radio waves travel at a known, fixed speed, that time delay tells the receiver exactly how far away each satellite is. Overlap those distances from enough satellites and you get a single point: your location.
That process is called trilateration, and it's worth getting right, because it's genuinely different from triangulation, which measures angles rather than distances. It's a small technical point, but it's the kind of detail that separates an accurate explanation from a recycled one.
New Zealand and Australia also benefit from SouthPAN, the Southern Hemisphere's first satellite-based augmentation system, live since September 2022. It corrects small GPS errors in real time, tightening accuracy for exactly the kind of use that matters to a business: knowing a vehicle is on the right side of the yard, not just somewhere in the general vicinity.
From Satellite to Screen: How a Tracker Becomes a Dashboard
Knowing your own position is one thing. Getting that position onto your phone while you're sitting in the office is another problem entirely, and it's the part most explanations skip straight past.
A GPS tracker works out its position exactly as described above, then has to send that data somewhere. Most vehicle and asset trackers do this over the ordinary cellular network, the same one your phone uses, sending small bursts of location data to a server every so often. That data lands in a fleet management dashboard or app, where you see it as a dot on a map, along with useful extras like speed, idle time, or a route history.
This is exactly why a tracker needs a SIM card and a small amount of mobile data every month, and why coverage matters just as much as GPS accuracy. A tracker that knows exactly where it is but has no signal to report through is still, for all practical purposes, invisible to you.
Vehicle Trackers vs Asset Trackers: Which Do You Need?
Does it matter whether you buy a "vehicle tracker" or an "asset tracker"? Genuinely, yes, and mixing the two up is one of the most common mistakes we see.
A vehicle tracker, such as the Mongoose VT904, wires into the vehicle's own electrical system. It draws power constantly, which means it can report in real time without worrying about battery life, and it can often tell you extras like ignition status and harsh braking events straight from the vehicle itself.
An asset tracker, like the Logic Connect Oyster3, is built for things with no ignition to tap into: trailers, generators, plant, shipping containers. It runs on its own internal battery and typically reports less frequently to conserve power, a sensible trade-off for gear that might sit in a yard for weeks between jobs.
For smaller, higher-theft-risk items, a compact option like the Spot Trace adds a theft-alert function, useful for a trailer, jet ski, or piece of kit that's genuinely tempting to a thief in an empty car park.
When Cellular Isn't Enough: Tracking in Remote NZ
What happens to a standard tracker the moment it drives out of cellular range? It stops reporting, full stop. For a delivery van in Tauranga that's rarely an issue. For a forestry crew on the Volcanic Plateau or a farm vehicle working the back paddocks, it's a genuine gap.
Satellite-based trackers and communicators close that gap by reporting position over a satellite network instead of the cellular grid. Devices like the Garmin inReach Mini and the ZOLEO Satellite Communicator keep reporting position and allow basic two-way messaging from genuinely remote country, well beyond where a standard tracker gives up.
These devices lean more towards personal and lone worker safety than fleet-wide vehicle tracking, but for a business with people working alone in NZ's more remote corners, that safety net matters just as much as knowing where the trucks are.
Is GPS Tracking Your Staff Actually Legal?
Can you legally fit a tracker to a company vehicle and watch where your team goes all day? Yes, but only if you do it properly, and "properly" isn't optional.
Under the Privacy Act 2020, GPS location data that can identify a person counts as personal information, and it has to be collected fairly and transparently. In practice, that means telling staff a vehicle is tracked, explaining why, and only using the data for the reason you gave them, fleet management, safety, or route efficiency, not as a general surveillance tool.
We've covered this properly in a dedicated guide, since it deserves more than a paragraph here. Read our full breakdown of GPS tracking and employee privacy in NZ before you fit anything to a vehicle someone else drives.
Choosing the Right Fleet Management Software
A tracker without decent software is just an expensive way to generate data nobody looks at. The platform behind it is where the actual value shows up.
Options like Logic Connect, Navman, and Viewtech Fleetview turn raw location pings into something usable: live maps, geofence alerts, idle time reports, and driver behaviour data like harsh braking or speeding. Pricing for these platforms is generally quoted per fleet, so it's worth getting a proper quote for your specific setup rather than guessing at a number.
The right platform depends on fleet size and what you actually want out of it. A five-vehicle trade fleet needs something simple. A council or logistics operation running dozens of vehicles across multiple depots needs proper reporting and driver management built in.
Is GPS Tracking Right for Your Business?
GPS tracking earns its keep if:
- You're chasing down where a vehicle or piece of plant is more often than you'd like to admit.
- You need honest data on hours, routes, or fuel use for compliance or cost control.
- Trailers, generators, or tools have a habit of quietly disappearing from the yard.
- You have staff working alone in areas with patchy or no cellular coverage.
Think it through further if:
- You're running one vehicle with a driver you trust completely and no compliance requirement to track it.
- You haven't yet worked out how you'll notify staff and handle the Privacy Act side properly.
Getting Set Up Right
GPS tracking isn't complicated once you understand the pieces: how position is calculated, how it gets back to you, and which hardware actually fits what you're tracking. Get those right, add a proper platform on top, and a business with even a small fleet stops guessing and starts knowing.
Mobile Systems Limited has been supplying and installing GPS fleet tracking and asset management systems from Mount Maunganui for over 25 years, covering vehicle trackers, asset trackers, satellite communicators, and the software platforms behind them. Equipment is supplied and supported nationwide, with on-site installation across the Bay of Plenty, Coromandel, Rotorua, Taupō, South Waikato, the Volcanic Plateau and Eastern Waikato.
