Radio communication terminal, base station, handoff control method and base station control method capable of achieving handoff while continuing service such as broadcast service and/or multicast service

• US 8,725,147 B2
• Filed: 05/31/2006
• Issued: 05/13/2014
• Est. Priority Date: 05/31/2005
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Kono, Kenji
• Primary Examiner(s): PATEL, MAHENDRA R
• Application Number:
  US11/444,972
• Publication Number:
  US 20070025295A1
• Time in Patent Office: 2,904 Days
• Field of Search: 370331-332, 370/338, 370/333, 370/335, 370/343, 370/465, 455436-440, 455/442, 455/466, 375/134, 375/267, 709/238
• US Class Current: 455/436
• CPC Class Codes: H04W 36/0007 for multicast or broadcast services, e.g. MBMS multicast or broadcast application services H04W4/06; resource management for broadcast services H04W72/30; connection management for selective distribution or broadcast H04W76/40
• CPC Class Codes: H04W 36/0072 of resource information of target access point
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 76/40 for selective distribution or broadcast

Abstract

A radio communication terminal (AT) includes a communication section for performing a radio communication with a base station, and a controller. Before performing a handoff from a first base station to another peripheral base station while receiving service information delivered by the first base station, the controller checks a progress of sequence of the service information being received. Then, the controller performs a handoff control depending on the check result. When it is determined that reception of a packet having the sequence number being received is to be completed within a certain time as a result of checking the progress, the controller suspends the handoff until the reception of the packet is completed.

Claims

1. A base station comprising:

a broadcasting section which performs a broadcast of at least one of a broadcast service and a multicast service;

a receiver which receives a first message indicating a handoff is to be performed from at least one radio communication terminal, the first message including identification information of the broadcast being received by the radio communication terminal, a sequence number of a packet received by the radio communication terminal, and information on a base station of a handoff destination;

a notifying section which notifies the base station of the handoff destination, of the identification information of the broadcast and the sequence number of the packet; and

a transmitter which transmits a second message indicating a time to perform the handoff to the radio communication terminal;

wherein

the packet is not a channel burst, and

when the receiver receives the first message from each of a plurality of radio communication terminals, the transmitter transmits the second message indicating the time to perform the handoff being set based on the first message that is received the latest to each of the plurality of radio communication terminals.

2. A base station control method comprising:

performing a broadcast of at least one of a broadcast service and a multicast service;

receiving a first message indicating a handoff is to be performed from at least one radio communication terminal that is receiving the broadcast, the first message including identification information of the broadcast being received by the radio communication terminal, a sequence number of a packet received by the radio communication terminal, and information on a base station of a handoff destination;

notifying the base station of the handoff destination, of the identification information of the broadcast and the sequence number of the packet; and

transmitting a second message indicating a time to perform the handoff to the radio communication terminal;

wherein

the packet is not a channel burst, and

when the first message is received from each of a plurality of radio communication terminals, the second message indicating the time to perform the handoff being set based on the first message that is received the latest is transmitted to each of the plurality of radio communication terminals.