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Aviation
Almost all modern aircraft are fitted with multiple GPS receivers. This provides pilots and sometimes passengers with a real-time aircraft position and map of each flight’s progress. GPS also allows airline operators to pre-select the safest, fastest and most fuel-efficient routes to each destination, and ensure that each route is followed as closely as possible when the flight is underway.
Marine
When high accuracy GPS is fitted to boats and ships, it allows captains to navigate through unfamiliar harbours, shipping channels and waterways without running aground or hitting known obstacles. GPS is also used to position and map dredging operations in rivers, wharfs and sandbars, so other boats know precisely where it is deep enough for them to operate.
Farming
Farmers rely on repeat planting season after season to maximise their crop productions. By putting GPS receivers on tractors and other agricultural equipment, farmers can map their plantations and ensure that they return to exactly the same areas when sewing their seeds in future. This strategy also allows farmers to continue working in lowvisibility conditions such as fog and darkness, as each piece of machinery is guided by its GPS position instead of visual references. High accuracy GPS is also used to map soil sample locations, allowing farmers to see where the soil is most fertile across individual fields or even entire farms.
Science
Scientists use GPS technology to conduct a wide range of experiments and research, ranging from biology to physics to earth sciences. Traditionally, when scientists wanted to understand where and how far animals roam, they had to tag animals with metal or plastic bands and then follow them to various locations to monitor their movement. Today, scientists can fit animals with GPS collars or tags that automatically log the animal’s movement and transmit the information via satellite back to the researchers. This provides them with more detailed information about the animal’s movements without having to relocate specific animals.
Earth scientists also use GPS technology to conduct a wide range of research. By installing high accuracy GPS receivers on physical features such as glaciers or landslips, scientists can observe and study both the speed and direction of movement, helping them to understand how landscapes change over time. Similarly, GPS receivers can be installed on solid bedrock to help understand very small and very slow changes in tectonic plate motion across the world.
Surveying
Surveyors are responsible for mapping and measuring features on the earth’s surface and under water with high accuracy. This includes things like determining land boundaries, monitoring changes in the shape of structures or mapping the sea floor. Surveyors have historically required line-of-sight between their instruments in order to undertake such work, but the availability of high accuracy GPS receivers has reduced the need for this. GPS can either be setup over a single point to establish a reference marker, or it can be used in a moving configuration to map out the boundaries of various features. This data can then be transferred into mapping software to create very quick and detailed maps for customers.
Military applications
The GPS system was originally developed by the United States Department of Defence for use by the US military, but was later made available for public use. Since then, GPS navigation has been adopted by many different military forces around the world, including the Australian Defence Force. Some countries have even decided to develop their own satellite navigation networks for use during wartimes. Today, GPS is used to map the location of vehicles and other assets on various battlefields in real time, which helps to manage resources and protect soldiers on the ground. GPS technology is also fitted to military vehicles and other hardware such as missiles, providing them with tracking and guidance to various targets at all times of the day and in all weather conditions.
Road Transport
Based on the number of GPS receivers sold globally, road transport applications are the majority users of GPS positioning for commercial fleet management and freight tracking, taxi services, public transport monitoring and passenger information, and emergency vehicle location, dispatch and navigation. Private car owners have also widely adopted in‑car GPS navigation systems and most automobile manufacturers now release new vehicles with optional factory-fitted GPS.
Telecommunications
GPS timing is important for telecommunications applications, particularly for mobile telephone networks. Synchronous technologies are much more efficient than asynchronous technologies but require a time source with appropriate accuracy, stability and reliability to operate effectively or at all, and GPS satellites can provide this. While ground‑based clocks are accurate enough for this purpose (especially with the availability of chip scale atomic clocks (CSAC)), the synchronisation of many such clocks is problematic. GPS allows the derivation of synchronised UTC time through resolving the signals from a number of atomic clock sources at known locations.