In an overlay, network-based Wireless Location System, Location
Measurement Units (LMUs) are used to collect radio signaling both in the
forward and reverse channels for use in TDOA and/or AoA positioning
methods. Information broadcast from the radio network and by global
satellite navigation system constellations can be received by the LMUs
and used to reduce the difficulty of initial system configuration and
reconfiguration due to radio network changes.