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Navigation satellites systems need a very precisely predictable orbits. A low orbit is influenced by not precisely predictable drag. A higher orbit is necessary to keep the influence of drag very low. To limit the number of necessary satellites, a high orbit is necessary too. A larger distance to ground increases the area on Earth where the satellite is visible and receivable.
To get very precise orbital data, the positions of the satellites must be measured from ground stations frequently. For measurement an orbit period of about 12 hours is used, the satellites will pass a ground station twice a day. For exact calculation, the length of a siderial day, 23 hours, 56 minutes and 4 seconds is used.
GPS uses 1/2 of a sideral day, 11:58:02 and an orbit height of 20192 km.
Other satellite navigation use similar orbit periods, 17 orbits per 8 to 10 sideral days.
Glonass uses 8/17 of a sideral day, 11:15:48 and an orbit height of 19140 km.
BeiDou uses 9/17 of a sideral day, 12:40:16 and an orbit height of 21224 km.
Galileo uses 10/17 of a sideral day, 14:04:45 and an orbit height of 23232 km.
The ratio of 1/2 may be also written as 17/34, the other ones as 16/34 , 18/34 and 20/34. The differences are small. Thus all satellites could be measured about twice a day from the same ground stations.
I calculated the orbit heights using an online calculator, the resulting values differ a little from those found in Wikipedia.