METHOD OF RESELECTING A CELL BY A MOBILE TERMINAL IN IDLE MODE IN A CELLULAR TELECOMMUNICATION NETWORK

• US 20080299975A1
• Filed: 08/12/2008
• Published: 12/04/2008
• Est. Priority Date: 11/28/2002
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Lambert, Jean Pierre, SANCHEZ, JAVIER
• Granted Patent: US 7,668,547 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 60/04 using triggered events

Abstract

A method of reselecting a cell by a mobile terminal in idle mode in a cellular telecommunication network in which the network sends to the terminal a list containing information with regard to the UMTS cells to be identified, and in which the mobile terminal periodically performs a series of procedures of identifying the cells and a series of intersystem measurements on the identified cells. Between two successive procedures of identification, the mobile terminal performs a series of procedures of measurement whose duration is fixed so that the total duration for performing a procedure of identification and the subsequent series of procedures of measurement is less than 25 seconds.

Claims

1. A GSM-UMTS dual mode mobile terminal comprising:

means for periodically performing a series of procedures of identifying UMTS cells and a series of intersystem measurements on the identified cells;

means for allocating, every 20 seconds, a time window for identifying new UMTS cells among a plurality of UMTS cells indicated to the mobile terminal by the network, said time windows being alternately assigned to various carrier frequencies used in the cells of the network; and

means for simultaneously performing, every five seconds, measurements on the UMTS cells already identified belonging to same carrier frequency.

2. The mobile terminal according to claim 1, further comprising means for performing a confirmation measurement on each new cell identified and satisfying a predefined reselection criterion, said confirmation measurement being performed at most five seconds after the identification of that new cell.