Method and apparatus for generating and transmitting channel feedback in mobile communication system employing two dimensional antenna array

A method of a user equipment to send feedback information to a base station, the method comprising:

• receiving a channel status indication reference signal (CSI-RS) from a base station;
• selecting a precoding matrix for all antenna port groups of the base station;
• determining an additional precoding matrix to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the precoding matrixes for all of the antenna port groups and the additional precoding matrix;
• generating feedback information comprising the selected precoding matrix and the additional precoding matrix, on a basis of the received CSI-RS;
• and
• transmitting the generated feedback information to the base station.

A method of a user equipment to send feedback information to a base station, the method comprising:

• receiving feedback configuration information from the base station;
• receiving a channel status indication reference signal (CSI-RS) from the base station;
• selecting a precoding matrix for each antenna port group of the base station;
• determining an additional precoding matrix to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the precoding matrixes selected respectively for the antenna port groups and the additional precoding matrix;
• generating feedback information comprising the selected precoding matrix and the additional precoding matrix, on a basis of the received feedback configuration information and the CSI-RS;
• and
• transmitting the generated feedback information to the base station,
• wherein receiving feedback configuration information comprises receiving feedback configuration information corresponding to antenna port groups of the base station and receiving additional feedback configuration information based on a relationship between the antenna port groups.

A method of a user equipment to send feedback information to a base station, the method comprising:

• transmitting first feedback information generated based on a first channel status indication reference signal (CSI-RS) from the base station;
• receiving a second CSI-RS beamformed on a basis of the first feedback information from the base station;
• generating second feedback information on a basis of the received second CSI-RS, to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the first feedback information and the second feedback information;
• and
• transmitting the second feedback information to the base station.

A method of a base station to receive feedback information from a user equipment, the method comprising:

• transmitting feedback configuration information to a user equipment (UE);
• transmitting a channel status indication reference signal (CSI-RS) to the UE;
• and
• receiving feedback information generated based on the feedback configuration information and the CSI-RS from the user equipment,
• wherein the feedback information is generated, by the UE, to comprise a precoding matrix and an additional precoding matrix, the precoding matrix is selected for each antenna port group of the base station, and the additional precoding matrix is determined to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the precoding matrixes selected respectively for the antenna port groups and the additional precoding matrix.

A method of a base station to receive feedback information from a user equipment (UE), the method comprising:

• receiving first feedback information from the user equipment;
• transmitting a channel status indication reference signal (CSI-RS) beamformed on the basis of the first feedback information to the user equipment;
• and
• receiving second feedback information generated based on the CSI-RS from the UE,
• wherein the second feedback information is generated, by the UE, to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the first feedback information and the second feedback information.

A base station capable of receiving feedback information from a user equipment (UE), comprising:

• a communicator configured to send and receive signals to and from the user equipment;
• and
• a controller configure to control the communicator to transmit feedback configuration information to the user equipment, transmit a channel status indication reference signal (CSI-RS) to the user equipment, and receive feedback information generated based on the feedback configuration information and the CSI-RS from the user equipment,
• wherein the feedback information is generated, by the UE, to comprise a precoding matrix and an additional precoding matrix, the precoding matrix is selected for each antenna port group of the base station, and the additional precoding matrix is determined to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the precoding matrixes selected respectively for the antenna port groups and the additional precoding matrix.

A base station capable of receiving feedback information from a user equipment (UE), comprising:

• a communicator configured to send and receive signals to and from the user equipment;
• and
• a controller configure to control the communicator to receive first feedback information from the user equipment, transmit a channel status indication reference signal (CSI-RS) beamformed on a basis of the first feedback information to the user equipment, and receive second feedback information generated based on the CSI-RS from the user equipment,
• wherein the second feedback information is generated, by the UE, to maximize a signal-to-noise ratio (SNR) of a signal, transmitted using a first channel which is based on a second channel corresponding to the first feedback information and the second feedback information.