US 6,983,148 B1
Handover performed within a base station controller
Olli Kirla, Espoo (Finland)
Assigned to Nokia Corporation, Espoo (Finland)
Appl. No. 10/89,190
PCT Filed Sep. 27, 2000, PCT No. PCT/FI00/00827
§ 371(c)(1), (2), (4) Date Mar. 27, 2002,
PCT Pub. No. WO01/24558, PCT Pub. Date Apr. 05, 2001.
Claims priority of application No. 19992090 (FI), filed on Sep. 29, 1999.
Int. Cl. H04Q 7/20 (2006.01)
U.S. Cl. 455—436 11 Claims
OG exemplary drawing
 
1. A method for performing a handover where a telecommunications channel used by a connection between a mobile station and a mobile services switching centre is changed in a mobile communications system where the telecommunications channel consists of a radio channel connecting the mobile station and a base station and of a channel connecting the base station and the mobile services switching centre, wherein the method comprises
selecting a new radio channel for the connection in question;
checking whether the handover is an internal handover of the base station controller where the base station employing the new radio channel and the base station employing the old radio channel are controlled by one and the same base station controller;
checking whether a predetermined trigger condition is met, said condition being met if either the speech coding method or the data transfer rate changes, or if both the speech coding method and data transfer rate change at the same time, in connection with the handover; and
directing a switching function located in the mobile services switching centre to perform the handover, provided that the checks show that the handover is an internal handover of the base station controller where the trigger condition is met, or alternatively
directing a switching function of the base station controller to perform the handover in question, provided that the checks show that the handover is an internal handover of the base station controller where the trigger condition is not met.