Patent ID: 6064888
Filing Date: 2000-05-16
Classification: G01S,H04W

Abstract:
A method for use in determining a geographical position of a mobile terminal in at least a TDMA or FDMA mobile radio system, comprising the steps of:receiving in said mobile radio system a request to determine said geographical position;determining whether said mobile terminal is operating in a conversational mode, and if not, establishing a call with said mobile terminal;attempting to ascertain an uplink time slot that is unused by said mobile terminal and a serving base station, and if successful, assigning said uplink time slot that is unused as a geographical position determining time slot, and if not successful, determining to interrupt unlink communication by assigning a time slot that is currently used by said mobile terminal as said geographical position determining time slot;ordering at least one base station to listen for a transmission from said mobile terminal and to perform a measurement associated with said determining said geographical position;sending an order from said serving base station to said mobile terminal to transmit at least one uplink signal at said geographical position determining time slot, said at least one uplink signal primarily for use in said measurement associated with said determining said geographical position;said mobile terminal transmitting said at least one uplink signal on a frequency assigned to said serving base station and at said geographical position determining time slot; andsaid at least one base station performing said measurement associated with said determining said geographical position.