The satellites measured by the SLR station can be split up in four main groups:
Passive/geodetic satellites are of spherical shape and constructed in a way not to be influenced by external forces except gravitation. Typically, a large amount of retro-reflectors leads to response signals for SLR measurements, which can be easily identified. Distances range from 800 to 20,000 km and their main area of use is highly precise measurements of the Earth's gravitational field.
Satellites in low Earth orbit (LEO) can be found in distances between 450 and 1,350 km. Their field of use is versatile and ranges from the measurement of Earth's ice mass, ocean currents, sea level rise etc. up to high resolution radar images. All of them need to know their accurate orbit, which is measured and determined by SLR data.
Besides the American and European satellite navigation systems, GPS and Galileo, several other countries such as China, Russia and India sent their own navigation satellites to space. Distances vary between 20,000 and 36,000 km, with total masses of 600 to 1,400 kg. Their field of use is the exact positioning and navigation on Earth.