HOW ACCURATE IS GPS?
Today's GPS receivers are extremely accurate, thanks to their parallel multichannel designs. Our receivers are quick to lock onto satellites when first turned on. They maintain tracking locks in dense tree cover or in urban settings with tall buildings. Certain atmospheric factors and other error sources can affect the accuracy of GPS receivers. Garmin GPS receivers are typically accurate to within 10 meters. Accuracy is even better on the water because there are no obstructions to interfere with the signal.
A Garmin GPS receiver’s accuracy is improved when using the Wide Area Augmentation System (WAAS). This capability can improve accuracy to better than 3 meters by providing corrections to the atmosphere and satellite positions. No additional equipment or fees are required to take advantage of WAAS satellites.
OTHER GPS SYSTEMS
There are other systems similar to GPS in the world, which are all classified as global navigation satellite systems (GNSS). GNSS is a generic term referring to all satellite navigation systems. Most Garmin receivers track GPS, GLONASS and Galileo, and some regional variations even track BeiDou and QZSS. These are sometimes referred to as multiconstellation receivers since they track and utilize multiple satellite constellations. Generally, you can expect a more reliable solution when you track more satellites. You could be tracking nearly 20 or 30 satellites with newer Garmin products.