Unified feedback frame for supporting a plurality of feedback modes and a multiple-input multiple-output (MIMO) communication system using the unified feedback frame

A communication method of a receiver in a MIMO communication system, the communication method comprising:

• estimating a channel formed between a transmitter and the receiver;
• accessing a base codebook comprising base codewords and an additional codebook comprising additional codewords;
• generating, based on the estimated channel, a base codeword indicator that indicates one of the base codewords included in the base codebook recommended for a wideband and an additional codeword indicator that indicates one of the additional codewords included in the additional codeword recommended for a sub-band from among a plurality of sub-bands included in the wideband;
• and
• transmitting the base codeword indicator recommended for the wideband and the additional codeword indicator recommended for the sub-band to the transmitter.

A transmitter supporting multiple feedback modes in a multiple-input multiple-output (MIMO) network, the transmitter comprising:

• a memory configured to store at least a first mode codebook and a second mode codebook;
• a receiving unit configured to receive, from a receiver, a first codeword indicator that indicates a first codeword from among a plurality of codewords included in the first mode codebook recommended for a wideband, and a second codeword indicator that indicates a second codeword out of a plurality of codewords included in the second mode codebook recommended for a sub-band from among a plurality of sub-bands included in the wideband;
• a precoding matrix generator configured to generate a precoding matrix for the receiver in the sub-band based on the first codeword indicator recommended for the wideband and the second codeword indicator recommended for the sub-band;
• a precoder configured to precode at least one data stream using the generated precoding matrix;
• and
• a transmitting unit configured to transmit the precoded at least one data stream to the receiver.

A receiver supporting multiple feedback modes in a multiple-input multiple-output (MIMO) network, the receiver comprising:

• a channel estimator configured to estimate a channel formed between the receiver and a transmitter;
• a memory configured to store at least a first mode codebook and a second mode codebook;
• and
• an indicator generator configured to generate a first codeword indicator that indicates a first codeword out of a plurality of codewords included in the first mode codebook recommended for a wideband, and configured to generate a second codeword indicator that indicates a second codeword out of a plurality of codewords included in the second mode codebook recommended for a sub-band from among a plurality of sub-bands included in the wideband;
• and
• a transmitting unit configured to transmit the first codeword indicator recommended for the wideband and the second codeword indicator recommended for the sub-band to the transmitter.