Cell selection techniques for femtocell measurements

1. A method comprising:

obtaining, at radio resource control (RRC) circuitry, a set of macrocell frequencies for measurement;

scheduling reselection measurements on the macrocell frequencies;

obtaining a set of potential femtocell frequencies;

selecting a particular femtocell frequency from the set of potential femtocell frequencies for measurement; and

excluding from a subsequent reselection measurement a selected macrocell frequency from the set of macrocell frequencies; and

during a scheduled measurement window for the selected macrocell frequency, preforming, via the RRC circuitry, a measurement at the particular femtocell frequency.

2. The method of claim 1 , where selecting comprises:

round-robin selection.

3. The method of claim 1 , where excluding comprises:

excluding the selected macrocell frequency responsive to an exclusion criterion.

4. The method of claim 1 , where excluding comprises:

excluding the selected macrocell frequency because no reselection timer is running for the selected macrocell frequency.

5. The method of claim 1 , where excluding comprises:

determining a frequency band that is not in use; and

determining that the selected macrocell frequency is within the frequency band.

6. The method of claim 5 , where determining the frequency band comprises:

obtaining a region code that indicates a current geographic region of operation; and

identifying the frequency band based on the region code.

7. The method of claim 6 , where identifying comprises:

determining that the frequency band is absent in a pre-configured table that links the region code to frequency bands that are in use in the current geographic region of operation.

8. The method of claim 6 , where the region code comprises:

a mobile country code.

9. A system comprising:

a radio frequency (RF) interface;

memory comprising:

a macrocell frequency list; and

a femtocell frequency list; and

radio resource control (RRC) circuitry in communication with the RF interface, the RRC circuitry configured to:

determine inter-frequency and intra-frequency measurement capabilities of the RF interface during an upcoming cell reselection measurement window;

determine a selected macrocell frequency from the macrocell frequency list to exclude from the cell reselection measurement window;

determine a selected femtocell frequency from the femtocell frequency list to measure instead of the selected macrocell frequency; and

schedule the selected femtocell frequency in the cell reselection measurement window as:

an inter-frequency measurement when the selected macrocell frequency was an inter-frequency macrocell; or

as an intra-frequency measurement, when the selected macrocell was an intra-frequency measurement.

10. The system of claim 9 , where the RRC circuitry is configured to determine to exclude by:

determining that no reselection timer is running for the selected macrocell frequency;

determining that the selected macrocell frequency is not in use in a geographic location in which the system is operating;

determining that the selected macrocell frequency is subject to round-robin replacement by the selected femtocell frequency;

or any combination of the above.

11. A system comprising:

a physical layer comprising a radio frequency (RF) communication interface; and radio resource control (RRC) circuitry coupled to the RF communication interface configured to:

obtain a set of macrocell frequencies for measurement;

schedule reselection measurements on the macrocell frequencies;

obtain a set of potential femtocell frequencies;

select a particular femtocell frequency from the set of potential femtocell frequencies for measurement; and

exclude from a subsequent reselection measurement a selected macrocell frequency from the set of macrocell frequencies; and

during a scheduled measurement window for the selected macrocell frequency, preform a measurement at the particular femtocell frequency.

12. The system of claim 11 , where:

the RRC circuitry is configured to schedule the reselection measurements by sending a round-robin scheduling request to the physical layer.

13. The system of claim 11 , where the RRC circuitry is further configured to obtain the set of potential femtocell frequencies from the RF communication interface.

14. The system of claim 13 , where the RRC circuitry is further configured to:

obtain the set of potential femtocell frequencies by receiving system information from a network controller in communication with the RF communication interface.

15. The system of claim 14 , where the system information comprises:

any combination of system information blocks (SIB) 11, SIB11.bis, SIB 12, and SIB 19.

16. The system of claim 11 , where the RRC circuitry is configured to exclude by:

comparing a reselection timer for the selected frequency to a timer threshold.

17. The system of claim 11 , where the RRC circuitry is configured to exclude by:

evaluating an exclusion criterion, other than a reselection timer, applicable to the selected macrocell frequency.

18. The system of claim 11 , where the RRC circuitry is configured to exclude by:

obtaining a code that indicates a geographic region of operation; and

exclude the selected macrocell frequency because it is not in use in the geographic region.

19. The system of claim 18 , where the code comprises a mobile country code.

20. The system of claim 18 , where the RRC circuitry is further configured to:

index the code into a frequency table to determine a frequency band including the selected macrocell frequency that is not in use in the geographic region.