User terminal

• US 10,582,437 B2
• Filed: 02/14/2019
• Issued: 03/03/2020
• Est. Priority Date: 04/10/2015
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Fujishiro, Masato, Yamazaki, Chiharu, Chang, Henry
• Primary Examiner(s): Tran, Mong-Thuy T
• Application Number:
  US16/276,486
• Publication Number:
  US 20190182742A1
• Time in Patent Office: 383 Days
• Field of Search: 455436
• CPC Class Codes: H04J 11/0093 Neighbour cell search
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A user equipment for a mobile communication system, and method and chip thereof, receives a first parameter and a second parameter broadcasted from the current serving cell, and reselects a target cell to be used as a serving cell from among plural cells operated at different frequencies. The first parameter defines a probability for performing reselection of the target cell, and the second parameter is a timer value to be set in a timer started at a timing at which a quality measurement for neighbor cells ends. Reselecting includes, after receiving the first and second parameter, periodically measuring qualities of neighbor cells at timer defined timings, comparing a value corresponding to IMSI of the user equipment with a value corresponding to the first parameter, and reselecting the target cell from among cells having a quality satisfying predetermined quality criteria, based on results of the quality measurement and the comparison.

Claims

1. A user equipment for a mobile communication system, comprising:

a receiver configured to receive a first parameter broadcasted from a current serving cell and a second parameter broadcasted from the current serving cell; and

a controller configured to reselect a target cell to be used as a serving cell from among a plurality of cells operated at different frequencies, wherein

the first parameter is a parameter that defines a probability for performing reselection of the target cell,

the second parameter is a timer value to be set in a timer started at a timing at which a quality measurement for neighbor cells ends, and

the controller is configured to

after receiving the first parameter and the second parameter, periodically measure qualities of neighbor cells when the timer expires,

compare a value calculated by modulo operation using IMSI (International Mobile Subscriber Identity) of the user equipment with a value corresponding to the first parameter, and

reselect the target cell from among cells having a quality satisfying predetermined quality criteria, based on results of the quality measurement and the comparison.

2. A method performed at a user equipment for a mobile communication system, comprising:

receiving a first parameter broadcasted from a current serving cell and a second parameter broadcasted from the current serving cell; and

reselecting a target cell to be used as a serving cell from among a plurality of cells operated at different frequencies, wherein

the first parameter is a parameter that defines a probability for performing reselection of the target cell,

the second parameter is a timer value to be set in a timer started at a timing at which a quality measurement for neighbor cells ends, and

the reselecting comprises;

after receiving the first parameter and the second parameter, periodically measuring qualities of neighbor cells when the timer expires;

comparing a value calculated by modulo operation using IMSI (International Mobile Subscriber Identity) of the user equipment with a value corresponding to the first parameter; and

reselecting the target cell from among cells having a quality satisfying predetermined quality criteria, based on results of the quality measurement and the comparison.

3. A chip for a user equipment for a mobile communication system, comprising:

at least one processor and at least one memory, the at least one processor configured to perform processes of;

receiving a first parameter broadcasted from a current serving cell and a second parameter broadcasted from the current serving cell; and

reselecting a target cell to be used as a serving cell from among a plurality of cells operated at different frequencies, wherein

the first parameter is a parameter that defines a probability for performing reselection of the target cell,

the second parameter is a timer value to be set in a timer started at a timing at which a quality measurement for neighbor cells ends, and

the reselecting comprises;

after receiving the first parameter and the second parameter, periodically measuring qualities of neighbor cells when the timer expires;

comparing a value calculated by modulo operation using IMSI (International Mobile Subscriber Identity) of the user equipment with a value corresponding to the first parameter; and

reselecting the target cell from among cells having a quality satisfying predetermined quality criteria, based on results of the quality measurement and the comparison.