An earth orbit that is lower to earth then both a medium and high earth orbit.

A: Low Earth orbit, B: Medium Earth orbit, & D: Geosynchronous orbit.

With large number of low-earth-orbit satellites and the geo-synchronous orbit stuffed full of communications satellites, there aren't all THAT many "medium" altitude satellites. But there are some.

The GPS navigation satellites, for example, are in highly inclined 12-hour orbits, and an unknown number of military "spy" satellites are in that middle range.

At present there are around 24-32 satellites orbiting in medium earth orbit(11,000 miles)
more the satellites more accurate navigation is produced.

Satellites orbit in several different regions of space in the sky. Orbits fall into 3 main categories based on distance: Low Earth Orbit (LEO) at an altitude of 160 - 2000 km, Medium Earth Orbit (MEO) at an altitude of 2000 - 35000 km, and High Earth Orbit (HEO) at altitudes greater than 36000 km. One special orbit in which a large number of satellites have been placed into is a geosynchronous earth orbit (GEO), which is at the exact distance such that the satellite orbits the earth at the same angular velocity at which the earth spins. Most satellites orbit in circular orbits. A few are in elliptical orbits in which their distance varies.