Handoff method for communication system using multiple wireless resources
First Claim
1. A wireless communications system comprising multiple base stations connected to a network, communication with a terminal being performed using multiple carriers, and a soft handoff of said terminal being performed among said multiple base stations, wherein when said terminal is in a soft handoff state between said first and second base stations, said first base station and second base station receive communication quality information about said multiple carriers from said terminal, wherein a termination message of a network side soft handoff which instructs termination of soft handoff of at least a second carrier to be determined based on the received communication quality information about at least a first carrier, is notified to said terminal from said first or second base station.
2 Assignments
0 Petitions
Accused Products
Abstract
In a wireless communications system operating according to CDMA or the like, when one terminal simultaneously performs communication using multiple wireless resources (e.g., multiple carriers), there was a problem that when it was attempted to guarantee network mobility by the same soft handoff system as in the case where communication was performed using only one wireless resource, efficiency suffered from the viewpoint of network forwarding load, processing load and wireless resource occupancy time. Soft handoff termination is judged and soft handoff is forcibly terminated according to whether or not the data rate obtained for all resources on the network side satisfies a requested rate, based on a reception state notification from a terminal concerning wireless resources. By performing this processing, the soft handoff period is shortened, sufficient received strength in the terminal is maintained and terminal mobility is guaranteed, while at the same time network forwarding load, terminal processing load and wireless resource occupancy time are suppressed to the absolute minimum.
27 Citations
20 Claims
-
1. A wireless communications system comprising multiple base stations connected to a network, communication with a terminal being performed using multiple carriers, and a soft handoff of said terminal being performed among said multiple base stations,
wherein when said terminal is in a soft handoff state between said first and second base stations, said first base station and second base station receive communication quality information about said multiple carriers from said terminal, wherein a termination message of a network side soft handoff which instructs termination of soft handoff of at least a second carrier to be determined based on the received communication quality information about at least a first carrier, is notified to said terminal from said first or second base station.
-
13. A control node connected between multiple base stations which perform communication between terminals using multiple carriers, these multiple base stations and a network, soft handoff of said terminal being performed among these multiple base stations,
wherein said node has: -
a first network interface part that performs transmission and reception of communication data of said terminal with said network;
a second network interface part that performs transmission and reception of communication data of said terminal between first and second base stations; and
a control part, wherein, when said terminal is in a soft handoff state between said first and second base stations, said second network interface part receives communication quality information about multiple carriers between this first or second base station and this terminal via said first or second base station, and wherein, the control part determines termination of a soft handoff of at least a second carrier based on the received communication quality information about said terminal from said first or second base station at least a first carrier, and notifies a network side soft handoff termination message which instructs the termination of a soft handoff of at least a second carrier to said terminal from said first or second base station. - View Dependent Claims (14, 15, 16, 17)
-
-
18. A base station in a wireless communications system having multiple base stations connected to a network which perform communication with a terminal using multiple carriers, soft handoff of said terminal being performed among these multiple base stations, said base station comprising:
-
a network interface part which performs transmission and reception of communication data of said terminal with the network and with other base stations;
a wireless part which performs transmission and reception of communication data between said base stations; and
a control part, wherein when said terminal is in a soft handoff state between this base station and other base stations, and when this base station is the origin of the base station handoff, said network interface part forwards communication data addressed to a terminal received from the network to said second base station, and wherein said control part notifies a network side soft handoff termination message which instructs termination of soft handoff of at least a second carrier to be determined based on the received communication quality information due to said base station or said other base stations for at least a first carrier, to said terminal from said first or second base station. - View Dependent Claims (19, 20)
-
Specification