Evolution of Positioning Techniques in Cellular Networks, from 2G to 4G

Table 2

RRLP error codes.

Error code	Description
	Undefined
	Not enough BTSs
	Not enough satellites
	EOTD Location Assistance Data missing
	EOTD Assistance Data missing
	A-GPS Location Assistance Data missing
	A-GPS Assistance Data missing
	Method not supported
	Not processed
	Ref. BTS for GPS not serving BTS
	Ref. BTS for EOTD not serving BTS