Method for minimizing current consumption at handover in multimode terminal and terminal for use in the same

• US 8,264,993 B2
• Filed: 12/26/2006
• Issued: 09/11/2012
• Est. Priority Date: 12/26/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Noh, Jeong-Min, Kim, Ho-Joong
• Primary Examiner(s): Patel, Nimesh
• Application Number:
  US11/645,478
• Publication Number:
  US 20070147302A1
• Time in Patent Office: 2,086 Days
• Field of Search: 370/324, 370/330, 370/395.62, 370/503, 370/507, 370/905, 370/331, 455/436, 455/552.1, 455/439, 455/442
• US Class Current: 370/311
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and a multimode terminal for minimizing current consumption and simultaneously reducing a handover processing time when a handover occurs between communication networks which provide communication services using different mobile communication technologies. The communication network modems of the multimode terminal are interconnected via a one-to-one communication path, so that a handover target communication network modem is powered on only when handover actually occurs. In this way, by efficiently determining a time point when the handover target communication network modem is powered on, a processing time according to the occurrence of handover can be reduced, and additional current consumption can be minimized.

Claims

1. A method for minimizing current consumption in a multimode terminal, which includes first and second modems supporting different communication services, when a handover is performed, the method comprising:

detecting, by the first modem operating in a first communication mode, a time point of the handover according to at least one handover condition from a first communication network and then transmitting a detection result to the first communication network;

receiving, by the first modem, a handover command from the first communication network in response to transmission of the detection result; and

transmitting, by the first modem, a power-on command to the second modem through a direct communication path interconnecting the first and second modems to switch the second modem to a second communication mode in which communication is performed through a second communication network.

2. The method as claimed in claim 1, wherein the first and second networks correspond to a Code Division Multiple Access (CDMA) network and a Wideband CDMA (WCDMA) network, respectively, the first and second communication modes correspond to a CDMA mode and a WCDMA mode, respectively, and the first and second moderns are modems for processing signals transmitted/received through the CDMA and WCDMA networks, respectively.

3. The method as claimed in claim 1, wherein the first and second networks correspond to a Global System for Mobile Communication (GSM) network and a Wideband Code Division Multiple Access (WCDMA) network, respectively, the first and second communication modes correspond to a GSM mode and a WCDMA mode, respectively, and the first and second modems are modems for processing signals transmitted/received through the GSM and WCDMA networks, respectively.

4. The method as claimed in claim 1, further comprising:

receiving a Measurement Control signal including the handover condition from the first communication network by the first modern operating in the first communication mode; and

detecting the time point when the handover condition is satisfied.

5. The method as claimed in claim 4, wherein in the step of detecting the time point, it is detected whether or not strength of a reception signal measured in the first modem satisfies a reference value which the first communication network specifies in order to determine the time point of the handover of the terminal communicating through the first modem.

6. The method as claimed in claim 1, further comprising:

analyzing the handover command in the first modem if the second modem is powered on;

extracting a Universal Handover Direction message based on analysis of the handover command; and

transferring the extracted Universal Handover Direction message to the second modem through the direct communication path.

7. A multimode terminal for minimizing current consumption when handover is performed between different communication networks, the terminal comprising:

a first modem for detecting a time point when at least one handover condition from a first communication network is satisfied and transmitting a detection result to the first communication network while operating in a first communication mode, and transmitting a power-on command to a second modem through a direct communication path interconnecting the first and second modems if a handover command received in response to transmission of the detection result; and

the second modem for attempting to acquire a second communication network if powered on according to the first modem'"'"'s power-on command, and performing a second communication mode through the acquired second communication network.

8. The terminal as claimed in claim 7, wherein the first and second networks correspond to a Code Division Multiple Access (CDMA) network and a Wideband CDMA (WCDMA) network, respectively, the first and second communication modes correspond to a CDMA mode and a WCDMA mode, respectively, and the first and second modems are modems for processing signals transmitted/received through the CDMA and WCDMA networks, respectively.

9. The terminal as claimed in claim 7, wherein the first and second networks correspond to a Global System for Mobile Communication (GSM) network and a Wideband Code Division Multiple Access (WCDMA) network, respectively, the first and second communication modes correspond to a GSM mode and a WCDMA mode, respectively, and the first and second modems are modems for processing signals transmitted/received through the GSM and WCDMA networks, respectively.

10. The terminal as claimed in claim 7, wherein the first modem detects the time point when the handover condition is satisfied based on a Measurement Control signal received from the first communication network while operating in the first communication mode, and transmits the detection result to the first communication network.

11. The terminal as claimed in claim 7, wherein if the second modem is recognized as being powered on, the first modern analyzes the handover command to extract a Universal Handover Direction message, and transfers the extracted Universal handover Direction message to the second modem so that the second modem can acquire the second communication network.