Method and apparatus for configuring channel quality indicator and method and apparatus for configuring modulation and coding scheme
Embodiments of the present disclosure provide a method and apparatus for configuring channel quality indicator (CQI) and a method and apparatus for configuring modulation and coding scheme. The method for configuring CQI includes: configuring UE with a CQI index table by an eNB via CQI index table indication information, so that the UE determines the configured CQI index table according to the indication information, and calculates a CQI index according to calculated precoding matrix indicator (PMI) and rank indication (RI) by using the configured CQI index table. With the embodiments of the present disclosure, the eNB may configure different UEs with different ‘4-bit CQI tables’ and/or ‘modulation and TBS index tables’ while keeping the CQI index and the I MCS bit number unchanged. Therefore, not only the CQI index and the I MCS bit number need not to be increased, but also normal configuration of the LTE system may be ensured.
1. A base station for configuring a User Equipment (UE) with a Channel Quality Indicator (CQI) index table selected from among at least two CQI index tables, the base station comprising:
a processor coupled with memory and arranged to configure the selected CQI index table to be used by the UE; and
a transceiver configured to transmit CQI index table indication information, the CQI index indication information indicating to the UE the configured CQI index table so the UE calculates a CQI index according to a precoding matrix indicator (PMI) and rank indication (RI) calculated by the UE using the configured CQI index table indicated by the CQI index indication information, wherein the CQI index table indication information is transmitted to the UE via Radio Resource Control (RRC) signaling.
2. The base station according to claim 1 , wherein the RRC signaling is carried via a common information element used for configuring PUCCH transmission.
3. The base station according to claim 1 , wherein the RRC signaling is carried via a UE-specific information element used for configuring PUCCH transmission.
4. The base station of claim 1 wherein one of the at least two CQI index tables is an alternative CQI index table.
5. The base station of claim 1 wherein one of the at least two CQI index tables is an extended CQI index table.
6. The base station of claim 5 wherein the extended CQI index table includes one or more CQI index corresponding to a modulation greater than 64QAM.
7. The base station of claim 5 wherein the extended CQI index table is a 4 bit CQI table.
8. A User Equipment (UE), comprising:
a receiver configured to receive Channel Quality Indicator (CQI) index table indication information transmitted by a base station, the CQI index table indication information indicating one of at least two CQI index tables, configured by the base station, to be used by the UE; and
a processor coupled to memory and configured to calculate a CQI index according to Precoding Matrix Indicator (PMI) and Rank Indication (RI) by using the CQI index table configured by the base station, wherein the CQI index table indication information is transmitted to the UE via Radio Resource Control (RRC) signaling.
9. The UE of claim 8 , further comprising a transmitter configured to report the calculated CQI index to the base station.
10. A communication system comprising:
a base station comprising:
a processor coupled with memory and arranged to configure a Channel Quality Indicator (CQI) index table selected from among at least two CQI index tables to be used by a User Equipment (UE); and
a transceiver configured to transmit CQI index table indication information, the CQI index information indicating to the UE the configured CQI index table; and
the UE comprising: a receiver configured to
receive the CQI index table indication information indicating the configured CQI index table transmitted by the base station; and
a processor coupled to memory and configured to calculate a CQI index according to a Precoding Matrix Indicator (PMI) and Rank Indication (RI) by using the configured CQI index table indicated by the received CQI index table indication information, wherein the CQI index table indication information is transmitted to the UE via Radio Resource Control (RRC) signaling.