Yet Another Satellite Navigation System
With so many SatNav systems to choose from (GPS, GLONASS, Galileo, BeiDou, NAVIC) why waste money creating another? A cheaper option is to merge the publicly available positioning data from them all to get increased precision.
As the Russians or Iranians (presumably) have demo-ed in Syria, current SatNav systems are vulnerable to electronic interference meaning they can't be relied upon for military applications. Better to invest in alternative navigation systems combining inertial + ground radar data etc. If you must have a private SatNav for military purposes, launch 3+ disposable micro-satellites near the target area (keeping the protocol secret). All major powers can destroy satellites from the ground, so you can't expect SatNav satellites to remain active for long in a real conflict.