Systems and methods for using enhanced receiver and gaps when handling interference
Systems and methods that enable use of enhanced receiver techniques together with measurement gaps for measuring or reading a signal or channel from a target cell are disclosed. In one embodiment, a wireless device has an enhanced receiver and operates to measure interference from a first cell during one or more gaps created for a second cell to thereby obtain one or more interference measurements and then mitigate the interference during reception of a signal from a cell other than the first cell based on the one or more interference measurements using an enhanced receiver technique. The one or more gaps for the second cell are one or more gaps in downlink reception from the second cell, uplink transmission to the second cell, or a combination thereof. In this manner, the need for simultaneous reception for both the first cell and the other cell for interference mitigation is avoided.
1. A method of operation of a wireless device having enhanced receiver capability in a cellular communications network, comprising:
measuring interference from a first cell during one or more gaps created for a second cell to obtain one or more interference measurements, the one or more gaps being one or more gaps in at least one of a group consisting of: downlink reception from the second cell and uplink transmission to the second cell; and
mitigating the interference during reception of a signal from a cell other than the first cell based on the one or more interference measurements using the enhanced receiver capability of the wireless device.
2. The method of claim 1 wherein the cell other than the first cell is the second cell.
3. The method of claim 2 wherein:
the interference from the first cell comprises interference generated by transmission of an interfering channel from the first cell; and
mitigating the interference comprises mitigating the interference during reception of a same channel type as the interfering channel from the second cell based on the one or more interference measurements using the enhanced receiver capability of the wireless device.
4. The method of claim 2 wherein a total time for performing reception of the signal from the second cell is extended to account for the one or more gaps.
5. The method of claim 2 wherein a total time for performing reception of the signal from the second cell excludes the one or more gaps.
6. The method of claim 2 wherein:
measuring the interference comprises measuring the interference from the first cell during the one or more gaps created for the second cell during a first time period; and
mitigating the interference comprises mitigating the interference during reception of a signal from the second cell during a second time period that occurs after the first time period and does not overlap the first time period.
7. The method of claim 2 wherein:
measuring the interference comprises measuring the interference from the first cell during the one or more gaps created for the second cell during a first time period; and
mitigating the interference comprises mitigating the interference during reception of a signal from the second cell during a second time period that overlaps a portion of the first time period.
8. The method of claim 2 further comprising:
autonomously creating the one or more gaps by the wireless device.
9. The method of claim 2 wherein creating the one or more gaps comprises:
receiving gap configuration information from a network node of the cellular communications network; and
creating the one or more gaps based on the gap configuration information.
10. The method of claim 9 wherein the gap configuration information comprises information that is indicative of a time domain pattern for interference measurements.
11. The method of claim 2 wherein the interference from the first cell is generated by at least a channel transmitted by the first cell.
12. The method of claim 2 wherein the interference from the first cell is generated by at least a channel transmitted by the first cell that includes system information for the first cell.
13. The method of claim 1 wherein:
measuring the interference from the first cell comprises measuring interference generated by transmission of a first interfering channel by the first cell during one or more gaps created for the second cell during a first time period to obtain a first interference measurement, the one or more gaps created for the second cell during the first time period being one or more gaps created in at least one group consisting of: downlink reception from the second cell and uplink transmission to the second cell; and
mitigating the interference comprises mitigating the interference generated by transmission of the first interfering channel during reception of a first victim channel from the cell other than the first cell during a second time period based on the first interference measurement;
wherein the method further comprises:
measuring interference generated by transmission of a second interfering channel by the first cell during one or more gaps created for the second cell during a third time period to obtain a second interference measurement, the one or more gaps created for the second cell during the third time period being one or more gaps created in at least one of a group consisting of: downlink reception from the second cell and uplink transmission to the second cell; and
mitigating the interference generated by transmission of the second interfering channel during reception of a second victim channel from the cell other than the first cell during a fourth time period based on the second interference measurement.
14. The method of claim 13 wherein the first, second, third, and fourth time periods are non-overlapping.
15. The method of claim 13 wherein at least two of the first, second, third, and fourth time periods partially overlap.
16. The method of claim 1 , wherein the enhanced receiver capability comprises mitigating or cancelling at least interference caused by one or more of the following channels transmitted by the first cell: Physical Broadcast Channel, PBCH, Physical Downlink Shared Channel, PDSCH, Physical Downlink Control Channel, PDCCH, Physical Control Format Indicator Channel, PCFICH, or Physical Hybrid Automatic Repeat Request Indicator Channel, PHICH.
17. A wireless device having enhanced receiver capability for operation in a cellular communications network, comprising:
a transceiver; and
a processor associated with the transceiver configured to:
measure interference from a first cell during one or more gaps created for a second cell to obtain one or more interference measurements, the one or more gaps created for the second cell being one or more gaps created in at least one group consisting of: downlink reception from the second cell and uplink transmission to the second cell; and
mitigate the interference during reception of a signal from a cell other than the first cell based on the one or more interference measurements using an enhanced receiver capability of the wireless device.