Method for mitigating outages in heterogeneous networks
View Patent ↗The present invention provides a method for mitigating outages in wireless communication systems using feedback for control channels formed by aggregating groups of resource blocks or resource elements, the method. One embodiment of the method includes generating control channel feedback at user equipment. The control channel feedback is generated using one or more measurements performed on signals received at the user equipment over a downlink control channel at a current aggregation level. The method also includes transmitting the control channel feedback over an uplink channel and using this information for the optimal implementation of Cell range expansion by the network.
1. A method of providing feedback for control channels formed by aggregating groups of resource blocks or resource elements, the method comprising:
generating control channel feedback at user equipment, wherein the control channel feedback is generated using at least one measurement performed on at least one signal received at said user equipment over a downlink control channel at a current aggregation level, and wherein the control channel feedback comprises a headroom indication that indicates a difference between a signal-to-interference-plus-noise ratio (SINR) on the downlink control channel at a target aggregation level for the downlink control channel and a SINR at an aggregation level one level higher than the target aggregation level; and
transmitting the control channel feedback over an uplink channel.
2. The method of claim 1 , wherein generating the control channel feedback comprises generating a channel quality indicator based on at least one measurement of a signal strength of said at least one signal received at said user equipment.
3. The method of claim 2 wherein generating the control channel feedback comprises determining the target aggregation level for the downlink control channel that achieves a predefined quality target over the downlink control channel.
4. The method of claim 3 , wherein determining the target aggregation level comprises comparing the target aggregation level to the current aggregation level and generating at least one bit indicating at least one of an increase, a decrease, and no change in the current aggregation level.
5. The method of claim 3 , wherein generating the control channel feedback comprises generating information indicating at least one of an increase, a decrease, and no change in the current aggregation level.
6. The method of claim 1 , wherein generating the control channel feedback comprises generating a headroom indication that indicates a difference between an SINR on the downlink control channel at the current aggregation level and an SINR at an aggregation level one level higher than the current aggregation level.
7. The method of claim 1 , comprising receiving information indicating a handoff bias for determining whether to hand off between a cell or sector that operates according to a first wireless access technology and a cell or sector that operates according to a second wireless technology, wherein the handoff bias is determined based upon the control channel feedback.
8. A method involving feedback for control channels formed by aggregating groups of resource blocks or resource elements, the method comprising:
receiving control channel feedback from user equipment at an access node, wherein the control channel feedback is generated using at least one measurement performed on at least one signal transmitted from the access node over a downlink control channel at a current aggregation level, and wherein the control channel feedback comprises a headroom indication that indicates a difference between a signal-to-interference-plus-noise ratio (SINR) at the user equipment at a target aggregation level for the downlink control channel and an SINR at an aggregation level one level higher than the target aggregation level; and
deciding whether to modify the current aggregation level based on the information conveyed by the control channel feedback.
9. The method of claim 8 , wherein receiving the control channel feedback comprises receiving information indicative of the target aggregation level for the downlink control channel that provides a signal energy that achieves a predefined target quality at said user equipment.
10. The method of claim 9 , wherein receiving said information indicative of the target aggregation level comprises receiving at least one bit indicating at least one of an increase, a decrease, and no change in the current aggregation level.
11. The method of claim 8 , wherein receiving the control channel feedback comprises receiving a headroom indication that indicates a difference between an SINR at said user equipment at the current aggregation level and an SINR at an aggregation level one level higher than the current aggregation level.
12. The method of claim 8 , comprising modifying the current aggregation level based on the information conveyed by the control channel feedback and transmitting control information on the downlink control channel at the modified aggregation level.
13. The method of claim 8 , comprising determining a handoff bias to be used by said user equipment to determine whether to hand off between a first cell or sector and a second cell or sector.
14. The method of claim 13 , wherein determining the handoff bias comprises determining the handoff bias between the first cell or sector that operates according to a first wireless access technology and the second cell or sector that operates according to a second wireless technology, wherein the handoff bias is determined based upon the control channel feedback.
15. A method involving feedback for control channels formed by aggregating groups of resource blocks or resource elements, the method comprising:
receiving control channel feedback from user equipment at an access node, wherein the control channel feedback is generated using at least one measurement performed on at least one signal transmitted from the access node over a downlink control channel at a current aggregation level, and wherein the control channel feedback comprises a headroom indication that indicates a difference between a signal-to-interference-plus-noise ratio (SINR) at the user equipment at a target aggregation for the downlink control channel and an SINR at an aggregation level one level higher than the target aggregation level; and
deciding whether to perform cell expansion based on the information conveyed by the control channel feedback.
16. The method of claim 15 , wherein deciding whether to perform said cell expansion comprises determining a handoff bias to be used by said user equipment to determine whether to hand off between a cell or sector that operates according to a first wireless access technology and a cell or sector that operates according to a second wireless technology, wherein the handoff bias is determined based upon the control channel feedback.
17. The method of claim 15 , comprising deciding whether to modify the current aggregation level based on the information conveyed by the control channel feedback.
18. The method of claim 15 , wherein receiving the control channel feedback comprises receiving control channel feedback that conveys information indicating at least one of an increase, a decrease, and no change in the current aggregation level.