RADIO COMMUNICATION TERMINAL DEVICE, RADIO COMMUNICATION CONTROL STATION DEVICE, AND RADIO COMMUNICATION METHOD

• US 20090219902A1
• Filed: 03/02/2007
• Published: 09/03/2009
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Sovereign Peak Ventures, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Aoyama, Takahisa
• Granted Patent: US 8,203,957 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Provided are a radio communication terminal device, a radio communication control station device, and a radio communication method capable of effectively managing a radio resource allocated to a terminal and context such as registration information when the terminal compatible with a plurality of different RATs moves between the RATs. According to them, when the WLAN Network control unit (110) detects the WLAN In Service state while the terminal (100) is connected to a Cellular Network, a RAT switching control unit (109) controls to switch the connection from the Cellular Network to the WLAN Network. When a timer (1) in the Cellular Network control unit (101) has expired, a registration update request is transmitted to the Cellular Network by using the WLAN and the Cellular Network exchange station updates the registration, thereby holding the context such as the registration information in the Cellular Network.

Claims

1. A radio communication terminal apparatus that is able to access a plurality of networks including a cellular network and a wireless LAN network, comprising:

a detection section that detects an in-service state or out-of-service state of each cellular network and wireless LAN network;

a switching section that switches a network to which the apparatus is connected, based on the in-service state or the out-of-service state of the detected cellular network and wireless LAN network; and

a requesting section that, when a connection to the cellular network is switched to a connection to the wireless LAN network, regularly requests the cellular network to keep a context including registration information in the cellular network via the wireless LAN network.

2. The radio communication terminal apparatus according to claim 1, further comprising an command section that, when a connection with the cellular network is switched to a connection with the wireless LAN network, commands the wireless LAN network to regularly request the cellular network to keep the context including registration information in the cellular network.

3. The radio communication terminal apparatus according to claim 1, further comprising a command section that commands a change of a timer in the cellular network that manages the storage of the context including registration information in the cellular network via the wireless LAN network.

4. A radio communication control station apparatus comprising:

a receiving section that receives a command for regularly requesting a cellular network to keep a context including registration information in a cellular network from a radio communication terminal apparatus; and

a requesting section that makes the request according to the command.

5. The radio communication control station apparatus according to claim 4, further comprising a reporting section that reports a timer value indicating a timing for updating registration information in the cellular network while the radio communication terminal apparatus is communicating with the cellular network and a timer value indicating timing of updating registration information in the cellular network while the radio communication terminal apparatus is connected to the wireless LAN network to the radio communication terminal apparatus.

6. A radio communication method for regularly requesting, when a radio communication terminal apparatus that is able to access a plurality of networks including a cellular network and a wireless LAN network switches a connection with the cellular network to a connection with the wireless LAN network, the cellular network to keep a context including registration information in the cellular network via the wireless LAN network.