Channel quality information feedback techniques
View Patent ↗Various embodiments are generally directed to improved channel quality information feedback techniques. In one embodiment, for example, an evolved node B (eNB) may comprise a processor circuit, a communication component for execution by the processor circuit to receive a channel quality index for a physical downlink shared channel (PDSCH), the channel quality index associated with a defined reference resource, and a selection component for execution by the processor circuit to select a modulation and coding scheme (MCS) for transmission over the PDSCH of user equipment (UE) data in one or more resource blocks, the selection component to compensate for a difference between a cell-specific reference signal (CRS) overhead of the defined reference resource and a CRS overhead of the one or more resource blocks when selecting the MCS. Other embodiments are described and claimed.
1. User equipment (UE), comprising:
a radio frequency (RF) receiver to receive a channel state information (CSI) reference signal (CSI-RS);
circuitry coupled to the RF receiver, the circuitry to derive a channel quality indicator (CQI) index for a frequency band of an orthogonal frequency-division multiple access (OFDMA) wireless communication system, the logic circuitry to derive the CQI index based on the CSI-RS, a CSI interference measurement (CSI-IM) resource, and a CSI reference resource of a shared wireless downlink channel, without reference to resource elements of the CSI reference resource that are allocated to an enhanced physical downlink control channel (EPDCCH); and
an RF transmitter coupled to the circuitry, the RF transmitter to transmit electromagnetic signals representing the CQI index on a wireless uplink channel.
2. The UE of claim 1 , the CQI index comprising CSI for a serving cell of the UE.
3. The UE of claim 1 , the CSI reference resource defined in a frequency domain by a group of downlink physical resource blocks corresponding to the frequency band.
4. The UE of claim 1 , a first three orthogonal frequency-division multiplexing (OFDM) symbols of the CSI reference resource to be occupied by control signals.
5. The UE of claim 1 , the CSI reference resource defined in a time domain by a single downlink subframe.
6. The UE of claim 1 , the logic to configure a CSI process to report CSI comprising the CQI index, a precoding matrix indicator (PMI) and a rank indication (RI).
7. The UE of claim 1 , the shared wireless downlink channel comprising a physical downlink shared channel (PDSCH).
8. The UE of claim 1 , comprising one or more RF antennas coupled to the RF transmitter.
9. The UE of claim 1 , comprising a touchscreen display.
10. User equipment (UE), comprising:
a radio frequency (RF) receiver to receive a channel state information (CSI) reference signal (CSI-RS);
circuitry coupled to the RF receiver, the circuitry to configure a channel state information (CSI) process to report a precoding matrix indicator (PMI), a rank indication (RI), and a channel quality indicator (CQI) index for an orthogonal frequency-division multiple access (OFDMA) frequency band, the circuitry to derive the CQI index based on the CSI-RS, a CSI interference measurement (CSI-IM) resource, and a CSI reference resource of a downlink shared channel, the CSI reference resource to comprise a same cell-specific reference signal (CRS) overhead as a CRS overhead corresponding to a number of CRS antenna ports of a serving cell of the UE; and
an RF transmitter coupled to the circuitry, the RF transmitter to transmit the CQI index over a wireless uplink channel.
11. The UE of claim 10 , the downlink shared channel comprising a physical downlink shared channel (PDSCH).
12. The UE of claim 10 , the CSI reference resource defined in a time domain by a single downlink subframe.
13. The UE of claim 10 , the CSI reference resource defined in a frequency domain by a group of downlink physical resource blocks corresponding to the OFDMA frequency band.
14. The UE of claim 10 , the logic to configure the CSI process to report CSI for a serving cell of the UE, the CSI comprising the CQI index, the PMI, and the RI.
15. The UE of claim 10 , the logic to derive the CQI index based on an assumption that no resource elements of the CSI reference resource are allocated to an enhanced physical downlink control channel (EPDCCH).
16. The UE of claim 10 , comprising one or more RF antennas coupled to the RF transceiver.
17. The UE of claim 10 , comprising a user input device.
18. At least one non-transitory computer-readable storage medium comprising a set of instructions that, in response to being executed on user equipment (UE), cause the UE to:
receive a channel state information (CSI) reference signal (CSI-RS) and a CSI interference measurement (CSI-IM) resource;
define a CSI reference resource of a wireless downlink channel to comprise a cell-specific reference signal (CRS) overhead including a same number of CRS overhead resource elements (REs) as a CRS overhead corresponding to a number of CRS antenna ports of a serving cell of the UE;
derive a channel quality indicator (CQI) index based on the CSI-RS, the CSI-IM resource, and the CSI reference resource; and
transmit the CQI index over a wireless uplink channel.
19. The at least one non-transitory computer-readable storage medium of claim 18 , comprising instructions that, in response to being executed on the UE, cause the UE to configure a CSI process to report the CQI index.
20. The at least one non-transitory computer-readable storage medium of claim 19 , comprising instructions that, in response to being executed on the UE, cause the UE to configure the CSI process to report the CQI index, a precoding matrix indicator (PMI) and a rank indication (RI).
21. The at least one non-transitory computer-readable storage medium of claim 18 , comprising instructions that, in response to being executed on the UE, cause the UE to:
determine a channel measurement based on the CSI-RS;
determine an interference measurement based on the CSI-IM resource; and
derive the CQI index based on the channel measurement, the interference measurement, and the CSI reference resource.
22. The at least one non-transitory computer-readable storage medium of claim 18 , comprising instructions that, in response to being executed on the UE, cause the UE to derive the CQI index without reference to a number of REs of the CSI reference resource that are allocated to an enhanced physical downlink control channel (EPDCCH).
23. The at least one non-transitory computer-readable storage medium of claim 18 , the wireless downlink channel to comprise a shared channel of an orthogonal frequency-division multiple access (OFDMA) wireless network.
24. The at least one non-transitory computer-readable storage medium of claim 18 , the wireless downlink channel to comprise a physical downlink shared channel (PDSCH).
25. The at least one non-transitory computer-readable storage medium of claim 18 , the CSI-RS to comprise a non-zero power (NZP) CSI-RS.