Interference measurement methods for advanced receiver in LTE/LTE-A
A method for receiving a PDCH is provided. The method includes receiving, by a UE, information identifying a plurality of resource elements that are transmitted with zero power in a resource block containing the PDCH; receiving, by the UE, a first DMRS on a first DMRS port transmitted from a first cell; and receiving, by the UE, the PDCH that is transmitted on the first DMRS port.
1. A method for estimating interference, the method comprising:
receiving, by a user equipment (UE), an enhanced physical downlink control channel (EPDCCH) from a first network node, wherein physical resource block (PRB) resources of the EPDCCH overlap PRB resources of a second network node;
receiving an indication of a demodulation reference signal (DMRS) port associated with the EPDCCH; and
estimating the interference according to the EPDCCH and the DMRS port,
wherein the DMRS port is orthogonal to a second DMRS port associated with a second EPDCCH of the second network node, and wherein orthogonality between the DMRS port and the second DMRS port is maintained by using an EPDCCH Identifier (ID).
2. The method of claim 1 , wherein the DMRS port is allocated to the EPDCCH.
3. The method of claim 2 , wherein orthogonality between the DMRS port and the second DMRS port is maintained by using at least one of a same cell identifier (ID) or a same scrambling ID to initialize pseudo-random sequences for DMRSs corresponding to the DMRS port and the second DMRS port.
4. The method of claim 1 , wherein at least one of the DMRS port, a DMRS sequence, and an aggregation level of the EPDCCH is coordinated between the first network node and the second network node to enable estimating the interference according to the EPDCCH and the DMRS port.
5. The method of claim 1 , further comprising receiving one or more virtual cell identifiers (IDs) used to generate DMRS sequences for the DMRS port associated with the EPDCCH.
6. The method of claim 1 , wherein an aggregation level of the EPDCCH is aligned with an aggregation level of an EPDCCH of the second network node such that the EPDCCH of the first network node and the EPDCCH of the second network node have uniform experience.
7. The method of claim 1 , further comprising determining, by the UE, whether a second DMRS port is being used for a transmission involving a different UE, wherein the UE determines that the second DMRS port is being used for the transmission involving the different UE when an energy level present on the second DMRS port is above a threshold, wherein the interference is further estimated according to the energy level present on the second DMRS port, and wherein the second DMRS port is associated with an EPDCCH of the second network node.
8. The method of claim 1 , wherein the UE is configured to receive the EPDCCH via a localized EPDCCH transmission in which the EPDCCH is transmitted to the UE in consecutive enhanced control channel elements (eCCEs).
9. A user equipment (UE) comprising:
a memory; and
a processor coupled to the memory, the processor configured to:
receive an enhanced physical downlink control channel (EPDCCH) from a first network node, wherein physical resource block (PRB) resources of the EPDCCH overlap PRB resources of a second network node;
receive an indication of a demodulation reference signal (DMRS) port associated with the EPDCCH; and
estimate the interference according to the EPDCCH and the DMRS port,
wherein the DMRS port is orthogonal to a second DMRS port associated with a second EPDCCH of the second network node, and wherein orthogonality between the DMRS port and the second DMRS port is maintained by using an EPDCCH Identifier (ID).
10. The UE of claim 9 , wherein the DMRS port is allocated to the EPDCCH.
11. The UE of claim 9 , wherein at least one of the DMRS port, a DMRS sequence, and an aggregation level of the EPDCCH is coordinated between the first network node and the second network node to enable estimating the interference according to the EPDCCH and the DMRS port.
12. The UE of claim 9 , wherein the processor is further configured to receive one or more virtual cell identifiers (IDs) used to generate DMRS sequences for the DMRS port associated with the EPDCCH.
13. The UE of claim 9 , wherein an aggregation level of the EPDCCH is aligned with an aggregation level of an EPDCCH of the second network node such that the EPDCCH of the first network node and the EPDCCH of the second network node have uniform experience.
14. The UE of claim 9 , wherein the processor is further configured to determine whether a second DMRS port is being used for a transmission involving a different UE, wherein the UE determines that the second DMRS port is being used for the transmission involving the different UE when an energy level present on the second DMRS port is above a threshold, wherein the interference is further estimated according to the energy level present on the second DMRS port, and wherein the second DMRS port is associated with an EPDCCH of the second network node.
15. A non-transitory storage medium comprising instructions that when executed by a processor cause the processor to:
receive an enhanced physical downlink control channel (EPDCCH) from a first network node, wherein physical resource block (PRB) resources of the EPDCCH overlap PRB resources of a second network node;
receive an indication of a demodulation reference signal (DMRS) port associated with the EPDCCH; and
estimate the interference according to the EPDCCH and the DMRS port,
wherein the DMRS port is orthogonal to a second DMRS port associated with a second EPDCCH of the second network node, and wherein orthogonality between the DMRS port and the second DMRS port is maintained by using an EPDCCH Identifier (ID).
16. The non-transitory storage medium of claim 15 , wherein the DMRS port is allocated to the EPDCCH.
17. The non-transitory storage medium of claim 15 , wherein at least one of the DMRS port, a DMRS sequence, and an aggregation level of the EPDCCH is coordinated between the first network node and the second network node to enable estimating the interference according to the EPDCCH and the DMRS port.
18. The non-transitory storage medium of claim 15 , wherein the instructions further cause the processor to receive one or more virtual cell identifiers (IDs) used to generate DMRS sequences for the DMRS port associated with the EPDCCH.
19. The non-transitory storage medium of claim 15 , wherein an aggregation level of the EPDCCH is aligned with an aggregation level of an EPDCCH of the second network node such that the EPDCCH of the first network node and the EPDCCH of the second network node have uniform experience.
20. The non-transitory storage medium of claim 15 , wherein the instructions further cause the processor to determine whether a second DMRS port is being used for a transmission involving a different UE, wherein the UE determines that the second DMRS port is being used for the transmission involving the different UE when an energy level present on the second DMRS port is above a threshold, wherein the interference is further estimated according to the energy level present on the second DMRS port, and wherein the second DMRS port is associated with an EPDCCH of the second network node.