Efficient resource utilization in TDD
In a wireless communication system unused resource elements are utilized to transmit additional pilot and control signals. The additional pilot and control signals may mitigate the impact of interference. The unused resource elements may be in a downlink pilot timeslot (DwPTS) in a time division duplex system.
1. A method for wireless communications, comprising:
determining a hybrid automatic repeat request (HARQ) timeline;
identifying downlink resource elements in a downlink pilot timeslot (DwPTS), based at least in part on a HARQ configuration of the HARQ timeline, the identified downlink resource elements being allocated for HARQ communications according to the HARQ configuration but remaining unused for HARQ communications during a subframe; and
utilizing the unused resource elements to transmit, by a base station, at least one of pilot signals and control signals during the subframe.
2. The method of claim 1 , in which the identified resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.
3. The method of claim 2 , further comprising:
utilizing the identified resource elements to increase a size of aggregation for a physical downlink control channel to mitigate an impact of interference.
4. The method of claim 2 , further comprising:
utilizing the identified resource elements to send information for another carrier.
5. The method of claim 2 , further comprising:
utilizing the identified resource elements to send information for another subframe.
6. The method of claim 1 , in which the identified resource elements are utilized for noise estimation in receiver processing.
7. The method of claim 1 , in which the identified resource elements are utilized by one or more weak cells for additional transmissions in at least one of: a physical control format indicator channel, a physical hybrid automatic repeat request indicator channel, and a physical downlink control channel.
8. The method of claim 1 , further comprising:
creating at least one identified resource element by not scheduling physical downlink shared channel transmissions in a downlink pilot timeslot.
9. The method of claim 1 , further comprising:
creating at least one identified resource element by advertising fewer symbols in the downlink pilot timeslot.
10. The method of claim 9 in which the advertising occurs semi-statically in a system information block (SIB).
11. The method of claim 9 in which the advertising is based on a deterministic function of at least one of a system frame number (SFN) and a cell identification number.
12. An apparatus for wireless communication, the apparatus comprising:
means for determining a hybrid automatic repeat request (HARQ) timeline;
means for identifying downlink resource elements in a downlink pilot timeslot (DwPTS), based at least in part on a HARQ configuration of the HARQ timeline, the identified downlink resource elements being allocated for HARQ communications according to the HARQ configuration but remaining unused for HARQ communications during a subframe; and
means for utilizing the unused resource elements to transmit, by a base station, at least one of pilot signals and control signals during the subframe.
13. A computer program product configured for wireless communications in a wireless network, the computer program product comprising:
a non-transitory computer-readable medium having program code recorded thereon, the program code comprising:
program code to determine a hybrid automatic repeat request (HARQ) timeline;
program code to identify downlink resource elements in a downlink pilot timeslot (DwPTS), based at least in part on a HARQ configuration of the HARQ timeline, the identified downlink resource elements being allocated for HARQ communications according to the HARQ configuration but remaining unused for HARQ communications during a subframe; and
program code to utilize the unused resource elements to transmit, by a base station, at least one of pilot signals and control signals during the subframe.
14. An apparatus configured for wireless communication, the apparatus comprising:
a memory; and
at least one processor coupled to the memory and configured:
to determine a hybrid automatic repeat request (HARQ) timeline;
to identify downlink resource elements in a downlink pilot timeslot (DwPTS), based at least in part on a HARQ configuration of the HARQ timeline, the identified downlink resource elements being allocated for HARQ communications according to the HARQ configuration but remaining unused for HARQ communications during a subframe; and
to utilize the unused resource elements to transmit, by a base station, at least one of pilot signals and control signals during the subframe.
15. The apparatus of claim 14 , in which the identified resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.
16. The apparatus of claim 15 , in which the at least one processor is further configured:
to utilize the identified resource elements to increase a size of aggregation for a physical downlink control channel to mitigate an impact of interference.
17. The apparatus of claim 15 , in which the at least one processor is further configured:
to utilize the identified resource elements to send information for another carrier.
18. The apparatus of claim 15 , in which the at least one processor is further configured:
to utilize the identified resource elements to send information for another subframe.
19. The apparatus of claim 14 , in which the identified resource elements are utilized for noise estimation in receiver processing.
20. The apparatus of claim 14 , in which the identified resource elements are utilized by one or more weak cells for additional transmissions in at least one of: a physical control format indicator channel, a physical hybrid automatic repeat request indicator channel, and a physical downlink control channel.
21. The apparatus of claim 14 , in which the at least one processor is further configured:
to create at least one identified resource element by not scheduling physical downlink shared channel transmissions in a downlink pilot timeslot.
22. The apparatus of claim 14 , in which the at least one processor is further configured:
to create at least one identified resource element by advertising fewer symbols in the downlink pilot timeslot.
23. The apparatus of claim 22 in which the advertising occurs semi-statically in a system information block (SIB).
24. The apparatus of claim 22 in which the advertising is based on a deterministic function of at least one of a system frame number (SFN) and a cell identification number.
25. A method for wireless communications, comprising: receiving, by a user equipment, at least one of pilot signals and control signals on downlink resource elements in a downlink pilot timeslot (DwPTS), the downlink resource elements being allocated for hybrid automatic repeat request (HARQ) communications and having been previously identified by an eNodeB as being available in a subframe due to no scheduled HARQ communications during the subframe according to a HARQ timeline.
26. The method of claim 25 , in which the downlink resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.
27. An apparatus configured for wireless communication, the apparatus comprising:
a memory; and
at least one processor coupled to the memory and configured:
to receive, by a user equipment, at least one of pilot signals and control signals on downlink resource elements in a downlink pilot timeslot (DwPTS), the downlink resource elements being allocated for hybrid automatic repeat request (HARQ) communications and having been previously identified by an eNodeB as being available in a subframe due to no scheduled HARQ communications during the subframe according to a HARQ timeline.
28. The apparatus of claim 27 , in which the downlink resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.
29. A computer program product configured for wireless communications in a wireless network, the computer program product comprising:
a non-transitory computer-readable medium having program code recorded thereon, the program code comprising:
program code to receive, by a user equipment, at least one of pilot signals and control signals on downlink resource elements in a downlink pilot timeslot (DwPTS), the downlink resource elements being allocated for hybrid automatic repeat request (HARQ) communications and having been previously identified by an eNodeB as being available in a subframe due to no scheduled HARQ communications during the subframe according to a HARQ timeline.
30. The non-transitory computer program product of claim 29 , in which the downlink resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.
31. An apparatus for wireless communications, comprising:
means for receiving, by a user equipment, at least one of pilot signals and control signals on downlink resource elements in a downlink pilot timeslot (DwPTS), the downlink resource elements being allocated for hybrid automatic repeat request (HARQ) communications and having been previously identified by an eNodeB as being available in a subframe due to no scheduled HARQ communications during the subframe according to a HARQ timeline; and
means for decoding the at least one of pilot signals and control signals.
32. The apparatus of claim 31 , in which the downlink resource elements are in physical downlink control channel (PDCCH) symbols in the DwPTS.