Apparatus and methods for facilitating cell reselection for higher priority layers

Patent metadata

Field	Value
Publication number	US-9615321-B2
Application number	US-201213454512-A
Country	US
Kind code	B2
Filing date	Apr 24, 2012
Priority date	Jun 21, 2011
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

User Equipments (UEs) can be adapted to enter into a lower RRC state from a higher RRC state, and search for one or more layers of higher priority within a predetermined period of time upon entering into the lower RRC state. According to at least one aspect, this search for one or more layers of higher priority may be performed irrespective of RF quality of a current serving cell. According to at least another aspect, this search for one or more layers of higher priority may be conducted within the predetermined period of time if a wait period has elapsed since the UE camped on the current serving cell. If the wait period has not elapsed since camping on the current serving cell, the search for one or more layers of higher priority may be performed within the predetermined period of time following a duration of the wait period.

First claim

What is claimed is:

1. A user equipment, comprising:
a communications interface adapted to facilitate wireless communications;
a storage medium; and
a processing circuit coupled with the communications interface and the storage medium, the processing circuit adapted to:
camp on a current serving cell;
after starting to camp on the current serving cell and while still camping on the current serving cell, enter into a lower radio resource control (RRC) state from a higher RRC state;
upon entering into the lower RRC state from the higher RRC state, wait for a duration of a wait period since starting to camp on the current serving cell to elapse prior to searching for one or more layers of higher priority; and
search for the one or more layers of higher priority, after waiting the duration of the wait period, within a first discontinuous reception (DRX) cycle after entering into the lower RRC state from the higher RRC state, irrespective of a radio frequency (RF) quality of the current serving cell.

2. The user equipment of claim 1 , wherein the lower RRC state comprises a stand-by state or an idle state, and the higher RRC state comprises a connected state.

3. The user equipment of claim 1 , wherein the lower RRC state comprises one of a CELL_PCH state, a URA_PCH state, or an idle state, and wherein the higher RRC state is a state other than the CELL_PCH state, the URA_PCH state, and the idle state.

4. The user equipment of claim 1 , wherein the RF quality of the current serving cell comprises received signal code power (RSCP) and E c /I 0 of the current serving cell.

5. The user equipment of claim 1 , wherein the wait period is equal to a delay period during which the processing circuit is adapted to delay before conducting a cell reselection procedure after camping on the current serving cell.

6. A method operational on a user equipment, comprising:
camping on a current serving cell;
after starting to camp on the current serving cell and while still camping on the current serving cell, entering into a lower radio resource control (RRC) state from a higher RRC state;
upon entering into the lower RRC state from the higher RRC state, waiting for a duration of a wait period since starting to camp on the current serving cell to elapse prior to searching for one or more layers of higher priority; and
searching for the one or more layers of higher priority, after waiting the duration of the wait period, within a first discontinuous reception (DRX) cycle after entering into the lower RRC state from the higher RRC state, regardless of a radio frequency (RF) quality of the current serving cell.

7. The method of claim 6 , wherein entering into a lower RRC state from a higher RRC state comprises:
entering into a stand-by state or an idle state from a connected state.

8. The method of claim 6 , wherein entering into a lower RRC state from a higher RRC state comprises:
entering into one of a CELL_PCH state, a URA_PCH state, or an idle state from an RRC state other than the CELL_PCH state, the URA_PCH state, and the idle state.

9. The method of claim 6 , wherein searching for one or more layers of higher priority after waiting the duration of the wait period, regardless of an RF quality of a current serving cell comprises:
searching for the one or more layers of higher priority within a first DRX cycle after waiting the duration of the wait period, regardless of respective values for received signal code power (RSCP) and for E c /I 0 of the current serving cell.

10. The method of claim 6 , wherein waiting for the duration of the wait period since starting to camp on the current serving cell to elapse comprises:
waiting for a period of time at least substantially equal to a period of time during which no cell reselection procedure is conducted after camping on the current serving cell.

11. A user equipment, comprising:
means for camping on a current serving cell;
means for entering, after starting to camp on the current serving cell and while still camping on the current serving cell, into a lower radio resource control (RRC) state from a higher RRC state;
means for waiting, upon entering into the lower RRC state from the higher RRC state, for a duration of a wait period since starting to camp on the current serving cell to elapse prior to searching for one or more layers of higher priority; and
means for searching for the one or more layers of higher priority, after waiting the duration of the wait period, within a first discontinuous reception (DRX) cycle after entering into the lower RRC state from the higher RRC state, irrespective of a radio frequency (RF) quality of the current serving cell.

12. The user equipment of claim 11 , wherein the lower RRC state includes a stand-by state or an idle state, and the higher RRC state includes a connected state.

13. The user equipment of claim 11 , wherein the lower RRC state comprises one of a CELL_PCH state, a URA_PCH state, or an idle state, and wherein the higher RRC state is a state other than the CELL_PCH state, the URA_PCH state, and the idle state.

14. A non-transitory computer-readable medium comprising code executable by a processor on a user equipment, comprising:
code for camping on a current serving cell;
code for entering, after starting to camp on the current serving cell and while still camping on the current serving cell, into a lower radio resource control (RRC) state from a higher RRC state;
code for waiting, upon entering into the lower RRC state from the higher RRC state, for a duration of a wait period since starting to camp on the current serving cell to elapse before searching for one or more layers of higher priority; and
code for searching for the one or more layers of higher priority, after waiting the duration of the wait period, within a first discontinuous reception (DRX) cycle after entering into the lower RRC state from the higher RRC state, independent of a radio frequency (RF) quality of the current serving cell.

15. The non-transitory machine-readable medium of claim 14 , wherein the lower RRC state includes a stand-by state or an idle state, and the higher RRC state includes a connected state.

16. The non-transitory machine-readable medium of claim 14 , wherein the lower RRC state comprises one of a CELL_PCH state, a URA_PCH state, or an idle state, and wherein the higher RRC state is a state other than the CELL_PCH state, the URA_PCH state, and the idle state.

17. A user equipment, comprising:
a communications interface adapted to facilitate wireless communications;
a storage medium; and
a processing circuit coupled to the communications interface and the storage medium, the processing circuit adapted to:
camp on a current serving cell;
after starting to camp on the current serving cell and while still camping on the current serving cell, enter into a lower radio resource control (RRC) state from a higher RRC state;
determine whether a wait period has elapsed since starting to camp on the current serving cell;
if the wait period has elapsed since starting to camp on the current serving cell, search for one or more layers of higher priority within a first discontinuous reception (DRX) cycle after entering into the lower RRC state from the higher RRC state; and
if the wait period has not elapsed since starting to camp on the current serving cell, search for one or more layers of higher priority within a second DRX cycle following a duration of the wait period.

18. The user equipment of claim 17 , wherein the lower RRC state comprises one of a CELL_PCH s

Assignees

• Pica Francesco
• Lee Heechoon
• Sambhwani Sharad Deepak
• Khan Uzma
• Qualcomm Inc

Inventors

• Pica Francesco
• Lee Heechoon
• Sambhwani Sharad Deepak
• Khan Uzma

Classifications

• H04W48/20 Primary

  Selecting an access point · CPC title

• H04W76/048

  Electricity · mapped topic

• H04W76/046

  Electricity · mapped topic

• H04W48/16

  Discovering, processing access restriction or access information · CPC title

• H04W76/28

  Discontinuous transmission [DTX]; Discontinuous reception [DRX] · CPC title