Blind decoding for an enhanced physical downlink control channel (EPDCCH)

1. At least one non-transitory machine readable storage medium having instructions embodied thereon for blind decoding downlink control information (DCI) from an enhanced physical downlink control channel (EPDCCH), the instructions when executed by one or more processors of a user equipment (UE) perform the following:

processing, at the UE, the EPDCCH received from a base station, wherein the EPDCCH includes the DCI; and

attempting one or more times to decode the DCI from enhanced control channel elements (ECCE) of the EPDCCH from physical resource block (PRB) region candidates in a PRB set using a selected set of enhanced resource element group (EREG) index maps for the ECCE until the DCI is successfully decoded.

2. The at least one non-transitory machine readable storage medium of claim 1 , wherein resource elements (REs) of a PRB pair include a block of symbols mapped in sequence to REs on an associated port when the REs of the PRB pair are part of EREGs assigned for the EPDCCH transmission.

3. The at least one non-transitory machine readable storage medium of claim 1 , further comprising instructions which when executed performs the following: decoding the DCI with an EREG index map associated with a same aggregation level used to encode the DCI.

4. The at least one non-transitory machine readable storage medium of claim 1 , wherein each EREG index map is configured for a different aggregation level (AL), and resource elements (REs) of a PRB pair include a block of complex-valued symbols y(0), . . . , y(M symb −1) mapped in sequence starting with y(0) to resource elements (k,l) on the associated antenna port when the REs are part of the EREGS assigned for the EPDCCH transmission, where M symb is a number of modulation symbols to transmit on a physical channel, and the mapping to resource elements (k,l) on antenna port p is an increasing order of first an index k and then an index l, starting with a first slot and ending with a second slot in a subframe.

5. The at least one non-transitory machine readable storage medium of claim 1 , wherein each EREG index map is used to determine which resource elements (RE) in a physical resource block (PRB) pair are associated with the ECCE for aggregation level.

6. The at least one non-transitory machine readable storage medium of claim 1 , further comprising instructions which when executed performs the following: failing to decode the DCI when an assumed aggregation level differs from an encoded aggregation level, wherein the processor attempts to decode with an EREG index map associated with the assumed aggregation level, and the encoded aggregation level is the same aggregation level used by the base station to encode the DCI for transmission in the EPDCCH.

7. The at least one non-transitory machine readable storage medium of claim 1 , further comprising instructions which when executed performs the following:

receiving a physical downlink shared channel (PDSCH) with the EPDCCH in a resource allocation (RA), wherein the RA is a RA type 0 , RA type 1 , or a RA type 2 defined in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard Release 11; and

rate matching the PDSCH around a physical resource block (PRB) pair including the DCI in the EPDCCH.

8. The at least one non-transitory machine readable storage medium of claim 1 , wherein the same aggregation level is used to encode the DCI in 1, 2, 4, 8, 16, or 32 ECCE.

9. The at least one non-transitory machine readable storage medium of claim 1 , further comprising instructions which when executed performs the following: resolving an aggregation level ambiguity.

10. The at least one non-transitory machine readable storage medium of claim 1 , further comprising instructions which when executed performs the following: resolving a lowest ECCE ambiguity.

11. A user equipment (UE) operable to blindly decode downlink control information (DCI) from an enhanced physical downlink control channel (EPDCCH), the UE comprising:

a transceiver configured to receive the EPDCCH from a base station, wherein the EPDCCH includes the DCI; and

one or more processors configured to attempt one or more times to decode the DCI from enhanced control channel elements (ECCE) of the EPDCCH from physical resource block (PRB) region candidates in a PRB set using a selected set of enhanced resource element group (EREG) index maps for the ECCE until the DCI is successfully decoded.

12. The UE of claim 11 , wherein resource elements (REs) of a PRB pair include a block of symbols mapped in sequence to REs on an associated port when the REs of the PRB pair are part of EREGs assigned for the EPDCCH transmission.

13. The UE of claim 11 , wherein the one or more processors are further configured to decode the DCI with an EREG index map associated with a same aggregation level used to encode the DCI.

14. The UE of claim 11 , wherein each EREG index map is configured for a different aggregation level (AL), and resource elements (REs) of a PRB pair include a block of complex-valued symbols y(0), . . . , y(M symb −1) mapped in sequence starting with y(0) to resource elements (k,l) on the associated antenna port when the REs are part of the EREGS assigned for the EPDCCH transmission, where M symb is a number of modulation symbols to transmit on a physical channel, and the mapping to resource elements (k,l) on antenna port p is an increasing order of first an index k and then an index l, starting with a first slot and ending with a second slot in a subframe.

15. The UE of claim 11 , wherein each EREG index map is used to determine which resource elements (RE) in a physical resource block (PRB) pair are associated with the ECCE for aggregation level.

16. The UE of claim 11 , wherein the one or more processors are further configured to fail to decode the DCI when an assumed aggregation level differs from an encoded aggregation level, wherein the processor attempts to decode with an EREG index map associated with the assumed aggregation level, and the encoded aggregation level is the same aggregation level used by the base station to encode the DCI for transmission in the EPDCCH.

17. The UE of claim 11 , wherein:

the transceiver is further configured to receive a physical downlink shared channel (PDSCH) with the EPDCCH in a resource allocation (RA), wherein the RA is a RA type 0 , RA type 1 , or a RA type 2 defined in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard Release 11; and

the one or more processors are further configured to rate match the PDSCH around a physical resource block (PRB) pair including the DCI in the EPDCCH.

18. The UE of claim 11 , wherein the same aggregation level is used to encode the DCI in 1, 2, 4, 8, 16, or 32 ECCE.

19. The UE of claim 11 , wherein the one or more processors are further configured to resolve an aggregation level ambiguity.

20. The UE of claim 11 , wherein the one or more processors are further configured to resolve a lowest ECCE ambiguity.

21. At least one non-transitory machine readable storage medium having instructions embodied thereon for blind decoding downlink control information (DCI) from an enhanced physical downlink control channel (EPDCCH), the instructions when executed by one or more processors of a user equipment (UE) perform the following:

processing, at the UE, the EPDCCH received from a base station, wherein the EPDCCH includes the DCI;

attempting one or more times to decode the DCI from enhanced control channel elements (ECCE) of the EPDCCH from physical resource block (PRB) region candidates in a PRB set using a selected set of enhanced resource element group (EREG) index maps for the ECCE until the DCI is successfully decoded, wherein the DCI is decoded with an EREG index map associated with a same aggregation level used to encode the DCI; and

failing to decode the DCI when an assumed aggregation level differs from an encoded aggregation level, wherein the processor attempts to decode with an EREG index map associated with the assumed aggregation level, and the encoded aggregation level is the same aggregation level used by the base station to encode the DCI for transmission in the EPDCCH,

wherein resource elements (REs) of a PRB pair include a block of symbols mapped in sequence to REs on an associated port when the REs of the PRB pair are part of EREGs assigned for the EPDCCH transmission.

22. The at least one non-transitory machine readable storage medium of claim 21 ,

wherein each EREG index map is configured for a different aggregation level (AL), and resource elements (REs) of a PRB pair include a block of complex-valued symbols y(0), . . . , y(M symb −1) mapped in sequence starting with y(0) to resource elements (k,l) on the associated antenna port when the REs are part of the EREGS assigned for the EPDCCH transmission, where M symb is a number of modulation symbols to transmit on a physical channel, and the mapping to resource elements (k,l) on antenna port p is an increasing order of first an index k and then an index l, starting with a first slot and ending with a second slot in a subframe.

23. The at least one non-transitory machine readable storage medium of claim 21 ,

wherein each EREG index map is used to determine which resource elements (RE) in a physical resource block (PRB) pair are associated with the ECCE for aggregation level.

24. The at least one non-transitory machine readable storage medium of claim 21 , further comprising instructions which when executed performs the following:

receiving a physical downlink shared channel (PDSCH) with the EPDCCH in a resource allocation (RA), wherein the RA is a RA type 0 , RA type 1 , or a RA type 2 defined in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard Release 11; and

rate matching the PDSCH around a physical resource block (PRB) pair including the DCI in the EPDCCH.

25. The at least one non-transitory machine readable storage medium of claim 21 , wherein the same aggregation level is used to encode the DCI in 1, 2, 4, 8, 16, or 32 ECCE.