Why is GPS Ineffective Inside Buildings? GPS Alternatives for Positioning and Tracking
Last update 30 JAN 2023
Source - Nikita_Krushko
The global positioning system (GPS) is widely used all over the world for navigation, tracking, and defining object location. Its operating principle is based on measuring the arrival time of the synchronized signal coming from satellites to antennas (receivers). The technology allows pinpoint the location outside the building with an accuracy of up to 5-10 m. However, in the case of indoor GPS tracking, the system loses its precision. That is due to the inability of signals to penetrate the structure of a building. To enable precise indoor positioning and navigation one should make use of GPS alternatives developed specifically for indoor environments.
Drawbacks of using GPS for Indoor Positioning
Positioning systems are actively used in healthcare, logistics, manufacturing.
In the case of indoor GPS, the average error is 6 meters. Under some conditions, it may not reach receivers or come with distortions and delays. Even advanced antennas can’t deliver the exact location inside buildings, tunnels, basements. Since the indoor GPS system works within an ultra-high radio frequency range, the quality of signals can be negatively affected by the following factors:
- thick walls;
- magnetic storms (rare);
- the low inclination of GPS orbits (for subpolar regions).
While using global positioning inside buildings, GPS signals are blocked or reflected by the walls of the building, thus becoming not powerful enough for localization. To ensure proper signal reception, receivers have to be installed near windows, which isn't always possible or convenient.
Alternative Technologies for Indoor Navigation and Tracking
Stable and accurate indoor navigation and positioning can be achieved by using technologies similar to GPS. Bluetooth® Low Energy, Wi-Fi, and UWB are the most effective ones. Let’s compare them in detail: GPS vs WiFi and Bluetooth vs GPS.
Bluetooth® Low Energy
One of the most convenient tools for tracking objects indoors is the Bluetooth Low Energy technology. To set up indoor positioning Bluetooth® Low Energy beacons should be installed inside the facility. The beacons then will emit Bluetooth® LE signals at a predefined frequency.
Advantages of the technology:
- low energy consumption;
- possibility to localize an object with an accuracy of up to several meters;
- simple deployment and minimal maintenance.
Autonomy and insignificant size the Bluetooth® LE technology is supported by most modern smartphones. It is the most economical one among similar systems on the market and provides high accuracy localization inside buildings.
GPS vs Wi-Fi
Wi-Fi technology is sometimes used as an alternative to GPS for indoor positioning. The reason for its popularity is its widespread occurrence. Access points can be found in any building, which allows leveraging of existing infrastructure.
The active range of access points is up to 150 m and positioning is carried out using smartphones.
Main advantages of the system:
- application based on the existing infrastructure;
- long-range of signal (up to 150 m);
- scalability without manual intervention;
- compatibility with other technologies for indoor navigation.
The UWB technology has a great potential for indoor positioning. It is the most accurate among the existing systems. Achievable accuracy is up to 20 cm. Calculations are performed with the help of ultra-wideband signals that are sent at a frequency of up to several GHz. The reception of these signals doesn’t require direct visibility and can be performed by a limited number of components.
Advantages of the platform:
- resistance to noises;
- spectral flexibility;
- simultaneous support of hundreds of channels;
- highly accurate object tracking.
Where can positioning without GPS be used?
In recent years navigation without GPS has been used by more and more companies. Modern alternatives to GPS are applied practically in all spheres of the economy, including industry, transport, trading, and medical institutions.
Modern technologies allow monitoring assets in real-time. They can help track the movement of any moving objects, such as forklifts, cranes, and other vehicles. When using the system, the management gets interactive maps and can track the movement of assets, as well as can avoid equipment downtime, minimizing the risks of emergencies.
Learn more about forklift monitoring systems.
In retail, the technologies help to improve customer service and increase profits. The systems are considered particularly relevant in big shopping centers. While visiting shops, visitors get the possibility to search for the required goods on the map and build the most optimal routes to them.
The advantage of navigation technologies for the management is in the fact that the system performs detailed analytics of the shop performance and provides information about visitors’ behavior and workflows, and helps to create heat maps. Thanks to this, shops can ensure more efficient management and optimize the arrangement of goods.
The use of indoor navigation technology at railway stations and airports significantly improves the performance of transport hubs. After the implementation into the company’s infrastructure, the platform can execute a wide range of functions:
- create digital maps with points of interest;
- build routes to the wanted places;
- ensure step-by-step navigation around the territory and halls;
- send out push notifications with information or targeted advertisements to passengers;
- track assets;
- create analytical reports.
The systems allow positioning clinics as modern and client-oriented institutions. Tracking medical equipment, preventing thefts, and monitoring the position of vehicles inside and outside the territory are some of the functions that can be performed by the system. This high-accuracy indoor positioning technology makes it possible to track the movements of patients around the hospital and come to the rescue if their get worse.
Navigine is ready to help you to choose an indoor positioning system to solve any task of positioning or tracking indoors. We provide our customers with effective tools that are fully consistent with the market needs.