CSI measurement, reporting and collision-handling
This invention sets conditions for user equipment responses to channel state indicator request in channel state information that may conflict.
1. A method of wireless communication for controlling channel quality indicator measurements comprising:
transmitting a channel state information request from a base station;
receiving the channel state information request at a user equipment;
making a channel quality measurement at the user equipment on a channel state information reference resource; and
transmitting a channel state information response from the user equipment via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein said user equipment is configured in transmission mode 9 and the channel state information resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.
2. The method of claim 1 , wherein:
said transmitting a channel state information response is periodic with each transmission occurring on a subframe having the smallest value nCQI_ref greater than or equal to 4 that corresponds to a valid downlink subframe.
3. The method of claim 2 , wherein:
a valid downlink subframe is a subframe containing a Cell-specific Channel State Information Reference Signal configured for the user equipment.
4. The method of claim 2 , wherein:
a valid downlink subframe is not a Multimedia Broadcast multicast service Single Frequency Network subframe.
5. The method of claim 2 , further comprising:
not transmitting a channel state information response when there is no valid downlink subframe.
6. The method of claim 1 , wherein:
said transmitting a channel state information response is aperiodic with each transmission occurring on a subframe following the a corresponding channel state request in an uplink Downlink Control Information format.
7. The method of claim 1 , wherein:
when a channel state information reference resource is a Cell-specific Channel State Information Reference Signal subframe the user equipment assumes a presence of the Cell-specific Channel State Information Reference Signals in determining a channel quality indicator index.
8. A method of wireless communication for controlling channel quality indicator measurements comprising:
transmitting a channel state information request from a base station;
receiving the channel state information request at a user equipment;
making a channel quality measurement at the user equipment on a channel state information reference resource;
transmitting a channel state information response from the user equipment via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein each radio frame is divided into a first set of subframes and a second set of subframes and said transmitting a channel state information request is periodic with a first periodicity for transmissions in said first set of subframes and a second periodicity for transmissions in said second set of subframes;
transmitting via Radio Resource Control from the base station a predetermined priority between said first set of subframes and said second set of subframes; and
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment transmits a response to the channel state information request corresponding to the set of subframes with higher priority.
9. The method of claim 8 , wherein:
a channel state information reference resource must be a Cell-specific Channel State Information Reference Signal subframe; and
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment selects for periodic Channel State Information reporting a most recent valid Cell-specific Channel State Information Reference Signal subframe n-n CQI — ref ,n CQI — ref ≧4 which belongs to the subframe subset(s) for which Channel State Infomiation report is sent.
10. The method of claim 8 , wherein:
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment selects a single Channel State Information reporting configuration of a predetermined offset and a predetermined periodicity.
11. The method of claim 8 , wherein:
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment transmits neither channel state information response.
12. The method of claim 8 , wherein:
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment transmits both channel state information responses in a same uplink subframe.
13. The method of claim 8 , wherein:
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment transmits a response to the channel state information request lying adjacent to n where
L
=
argmax
l
=
1
,
2
n
CQI_ref
,
l
.
14. The method of claim 8 , wherein:
when said first periodicity and said second periodicity causes conflict in transmitting a channel state information response from the user equipment, the user equipment transmits a response to the channel state information request lying spaced from n where
L
=
argmax
l
=
1
,
2
n
CQI_ref
,
l
.
15. A method of wireless communication for controlling channel quality indicator measurements comprising:
transmitting a channel state information request from a base station; and
receiving in the base station a channel state information response from a user equipment via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein said user equipment is configured in transmission mode 9 and a channel state information reference resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.
16. A method of wireless communication for controlling channel quality indicator measurements comprising:
receiving in a user equipment a channel state information request from a base station;
making a channel quality measurement at the user equipment on a channel state information reference resource; and
transmitting a channel state information response from the user equipment via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein said user equipment is configured in transmission mode 9 and the channel state information reference resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.
17. An apparatus, comprising:
circuitry for transmitting a channel state information request; and
circuitry for receiving a channel state information response from a user equipment via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein said user equipment is configured in transmission mode 9 and a channel quality indicator reference resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.
18. An apparatus, comprising:
circuitry for receiving a channel state information request;
circuitry for making a channel quality measurement on a channel state information reference resource; and
circuitry for transmitting a channel state information response via one of a Physical Uplink Control CHannel and a Physical Uplink Shared CHannel on an uplink subframe wherein said user equipment is configured in transmission mode 9 and the channel state information reference resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.