Radio communication system channel state information feedback method and device

A method for Channel State Information, CSI, feedback in a wireless communication system, comprising:

• determining parameters required for the CSI feedback in a first wireless communication system, the parameters including a feedback period P of optimum subband Pre-encoding Matrix Information, PMI, the number of times K of information feedback for each of Bandwidth Parts, BPs, in system bandwidth within the feedback period P of the optimum subband PMI, a time interval Np between adjacent BP information feedback within the feedback period P of the optimum subband PMI, and a feedback period and a feedback position offset of wideband CSI, so that a feedback structure of the first wireless communication system in Physical Uplink Control Channel, PUCCH, is based on a feedback structure of a second wireless communication system in the PUCCH;
• notifying the parameters to a user equipment;
• transmitting a Channel State Information Reference Symbol, CSI-RS, to the user equipment periodically, so that the user equipment calculates the CSI required to be fed back;
• and
• receiving the CSI fed back by the user equipment according to the feedback structure of the first wireless communication system in the PUCCH in response to the CSI-RS, wherein the optimum subband PMI fed back is information obtained by jointly encoding the optimum subband PMI in all of the BPs,
• wherein determining the parameters required for the CSI feedback in the first wireless communication system comprises:
• configuring the feedback period P of the optimum subband PMI and the feedback period and feedback position offset of the wideband CSI through a high layer, wherein the feedback period P of the optimum subband PMI is an integral multiple of a transmission period of the CSI-RS;
• firstly determining the number of times K of information feedback, and then calculating, in accordance with the feedback period P of the optimum subband PMI, the number of times K of information feedback, and a number J of the BPs in the system bandwidth, the time interval Np through a formula of Np=└P/(J*K+1)┘, and
• notifying the parameters to the user equipment comprises:
• transmitting information containing the feedback period P of the optimum subband PMI, the number of times K of information feedback, and the feedback period and feedback position offset of the wideband CSI to the user equipment, wherein the user equipment calculates the time interval Np through the formula of Np=└P/(J*K+1)┘,
• or
• wherein determining the parameters required for the CSI feedback in the first wireless communication system comprises:
• configuring the feedback period P of the optimum subband PMI and the feedback period and feedback position offset of the wideband CSI through a high layer, wherein the feedback period P of the optimum subband PMI is an integral multiple of a transmission period of the CSI-RS;
• firstly determining the time interval Np, and then calculating, in accordance with the feedback period P of the optimum subband PMI, the time interval Np, and a number J of the BPs in the system bandwidth, the number of times K of information feedback through a formula of K=└(P/Np−1)/J┘, and
• notifying the parameters to the user equipment comprises:
• transmitting information containing the feedback period P of the optimum subband PMI, the time interval Np, and the feedback period and feedback position offset of the wideband CSI to the user equipment, wherein the user equipment calculates the number of times K of information feedback through the formula of K=└(P/Np−1)/J┘.

An apparatus for Channel State Information, CSI, feedback in a wireless communication system, comprising:

• a parameter determination unit adapted to determine parameters required for the CSI feedback in a first wireless communication system, the parameters including a feedback period P of wideband CSI, the number of times K of information feedback for each of Bandwidth Parts, BPs, in system bandwidth within the feedback period P of the wideband CSI, and a time interval Np between adjacent BP information feedback within the feedback period P of the wideband CSI, so that a feedback structure of the first wireless communication system in Physical Uplink Control Channel, PUCCH, is based on a feedback structure of a second wireless communication system in the PUCCH;
• a parameter notification unit adapted to notify the parameters determined by the parameter determination unit to a user equipment;
• a signaling transmission unit adapted to transmit a Channel State Information Reference Symbol, CSI-RS, to the user equipment periodically, so that the user equipment calculates the CSI required to be fed back;
• and
• a feedback information reception unit adapted to receive the CSI fed back by the user equipment according to the feedback structure of the first wireless communication system in the PUCCH in response to the CSI-RS transmitted by the signaling transmission unit, wherein information fed back for each BP is information obtained by jointly encoding optimum subband Channel Quality Information, CQI, with optimum subband Pre-encoding Matrix Information, PMI, in the BP,
• wherein the parameter determination unit is adapted to configure the feedback period P of the wideband CSI through a high layer, so that the feedback period P of the wideband CSI is an integral multiple of a transmission period of the CSI-RS, and to firstly determine the number of times K of information feedback, and then calculate, in accordance with the feedback period P of the wideband CSI, the number of times K of information feedback, and a number J of the BPs in the system bandwidth, the time interval Np through a formula of Np=└P/(J*K+1)┘, and
• the parameter notification unit is adapted to transmit information containing the feedback period P of the wideband CSI and the number of times K of information feedback to the user equipment, so that the user equipment calculates the time interval Np through the formula of Np=└P/(J*K+1)┘,
• or
• wherein the parameter determination unit is adapted to configure the feedback period P of the wideband CSI through a high layer, so that the feedback period P of the wideband CSI is an integral multiple of the transmission period of the CSI-RS, and to firstly determine the time interval Np, and then calculate, in accordance with the feedback period P of the wideband CSI, the time interval Np, and a number J of the BPs in the system bandwidth, the number of times K of information feedback through a formula of K=└(P/Np−1)/J┘, and
• the parameter notification unit is adapted to transmit information containing the feedback period P of the wideband CSI and the time interval Np to the user equipment, so that the user equipment calculates the number of times K of information feedback through the formula of K=└(P/Np−1)/J┘.