Location devices are one of the most affordable car safety solutions and business aids. These small devices are used to track and monitor vehicles and items that require extra security. The tracker performs more functions when connected to the car than providing real-time location. It can set virtual boundaries, send speeding alerts, and detect vibrations. Due to the small size of the device and the many tasks it performs, it is indeed something that everyone should use and enjoy the benefits. In addition, from a business perspective, it is considered a resource that can monitor assets in the field. These trackers are very useful for businesses involved in transportation, such as taxi services and delivery networks. A fleet of taxis can be tracked using a single computer application. Now let’s take a deeper look at how GPS works.
- Satellite Transmitted Signals
GPS Satellites: The Global Positioning System consists of 24 (31 plus backup satellites) satellites orbiting the earth, which orbit according to a predetermined orbit, ensuring that signals from at least 4 satellites can be received simultaneously anywhere on the earth.
Signal Content: Unique identifier (ID) of the satellite.
Precise timestamp (using the atomic clock on the satellite).
Current position of the satellite (orbital information, called ephemeris).
- Receiver receives signal
The built-in receiver of the GPS locator receives radio signals from multiple satellites.
The receiver decodes the satellite’s time and position data through the signal content.
- Distance calculation
Signal propagation time: The receiver calculates the time delay of the satellite signal from sending to receiving.
Distance calculation formula: Distance = signal propagation time × speed of light Distance = signal propagation time \times speed of light Distance = signal propagation time × speed of light Since radio signals propagate at the speed of light, the receiver can calculate the distance to each satellite through the propagation time.
- Triangulation positioning
In order to determine the position of the receiver, signals from at least 4 satellites are required: 3 satellites provide the position in three-dimensional space (longitude, latitude and altitude).
The 4th satellite is used to correct the receiver clock error.
Triangulation method: The distance between each satellite and the receiver corresponds to a sphere centered on the satellite.
The intersection of the 4 satellites is the position of the receiver.
- Error correction and optimization
Time error: The receiver uses 4 satellites to correct its internal clock error.
Signal interference: Buildings, terrain and atmosphere on the earth’s surface may cause signal delays. The GPS system will improve positioning accuracy through modeling (such as correction of ionospheric errors).
Differential GPS (DGPS): Further error correction through ground reference stations provides higher positioning accuracy.
- Final positioning results
The GPS receiver calculates and outputs the current longitude, latitude and altitude information.
Advanced equipment may further combine geographic information systems (GIS) to provide navigation functions.
Common sources of error
Satellite clock error: Satellite time is not synchronized with ground time.
Signal multipath effect: Path delay caused by signal reflection.
Atmospheric refraction: The propagation speed of signals in the ionosphere and troposphere is affected.
Geometric Dilution of Precision (GDOP): When the spatial distribution of satellites is not good, it affects positioning accuracy.
GPS receiver and integrated program console
The GPS receiver is responsible for connecting the tracker device to the GPS satellites in space. The device receives incoming signals from satellites. It needs signals from at least 4 satellites to locate the position of the GPS receiver on the earth. There are 32 GPS satellites covering the entire earth. The accuracy of GPS location mapping increases when the GPS receiver receives signals from more than 4 satellites.
Program console is a microchip that acts as a motherboard for communication between different components in the location tracker. It is the basis for performing computational tasks and exchanging result outputs between components in the locator device. It also takes care of the coordination work between connected components.
Network adapter
The network adapter helps the locator device to send data from the tracking device to the server with the help of the internet. It houses the SIM card that connects the locator device to the cloud server. The data includes the coordinates of the current location and data from other components. This information is instantly transmitted to the server so that the user can analyze it in real time.
In fact, these data transmissions are fast and are updated within nanoseconds, thus enabling real-time tracking.
Web application
The web application helps us visualize the data from the locator device for better understanding. It is stored on a secure server so that only authorized personnel can view it on their mobile phones or desktops. The data from the GPS tracker is carefully processed and displayed on the application dashboard from which we can draw useful inferences.
For businesses, the dashboard on the geo tracker device helps to understand the asset configuration and running costs.
How a Navigation Tracker Works – Step by Step Explanation
The system working procedure of the locator device is as follows: Once the navigation tracker is connected to the car, it tries to capture the signal from the satellite network. As mentioned earlier, the program console then uses the time required to receive the signal and the speed of the signal to determine the distance between the GPS receiver and the satellite. These distances from different satellites can be further used to determine the location on the earth. All these calculations happen in a fraction of a second, so there is no delay in the calculations.
Once the location is determined, the car tracking device tries to send the data to the end user using the internet. For this purpose, the satellite tracker has a network adapter enabled. Usually, M2M SIM cards work well regardless of the country. This means that one SIM card can be used in all countries without any additional costs. The data of the locator device is first recorded and processed in the server and then made available to the user device in a more comprehensive manner.
GPS Tracker for Fleet Management
The tracking unit can be used for fleet management. Unlike tracking a single vehicle, fleet management requires powerful computing and data transmission speed. The advantage of using a geo tracker for fleet management is that it only requires one application interface to manage all location trackers on different vehicles.
Fleet management offers many additional options to the customers. Using the Fniot portal, users can easily find nearby devices. The heat map on the app tells us where the vehicle spends most of its time.
Summary
GPS locators use satellite signals to calculate the distance to multiple satellites through signal propagation time, and determine the current location through triangulation. After error correction, it provides accurate location information. This technology is widely used in navigation, transportation, surveying, military and other fields.
