Information Transmission Method, Access Network Device, and Terminal Device

An access network device, comprising:

• a transmitter configured to:
• send a channel state information-reference signal (CSI-RS) configuration parameter to a user equipment (UE), wherein the CSI-RS configuration parameter comprises a quantity of CSI-RS signals to be sent by the access network device at each level and a sampling rate at each level;
• and
• send, based on the quantity of CSI-RS signals at each level, a CSI-RS signal corresponding to each level to the UE;
• and
• a receiver configured to receive a beamforming parameter at each level that is reported by the UE for the CSI-RS signal at each level, wherein the beamforming parameter at each level is determined by the UE based on the CSI-RS signal at each level and the sampling rate at each level, wherein a width of a beam represented by the beamforming parameter at each level is less than a width of beamforming used for delivering the CSI-RS signal at each level, and wherein a width of beamforming used for delivering a CSI-RS signal at a current level is less than or equal to a width of a beam represented by a beamforming parameter reported at a previous level.

A terminal device, comprising:

• a receiver configured to:
• receive a channel state information-reference signal (CSI-RS) configuration parameter sent by an access network device, wherein the CSI-RS configuration parameter comprises a quantity of CSI-RS signals to be sent by the access network device at each level and a sampling rate at each level;
• and
• receive a CSI-RS signal at each level that is sent by the access network device;
• and
• a processor coupled to the receiver and configured to:
• determine a beamforming parameter at each level based on the CSI-RS signal at each level and the sampling rate at each level;
• and
• report the beamforming parameter at each level to the access network device, wherein a width of a beam represented by the beamforming parameter at each level is less than a width of beamforming used for delivering the CSI-RS signal at each level, and a width of beamforming used for delivering a CSI-RS signal at a current level is less than or equal to a width of a beam represented by a beamforming parameter reported at a previous level.