| 摘要 |
This application relates to a wireless communication system, i.e. a wireless communication system using multiple-input multiple-output (MIMO) antennas for both a transmitting end and a receiving end. In particular, the wireless communication system is provided with a transmitter and a receiver, wherein the transmitter comprises a multi-stage precoder for transmitting signals through two layers and is technically characterized by: receiving, from the receiver, channel information comprising a first channel state information item indicating one of precoding matrices including four adjacent beam-forming vectors performing beam forming and a second channel state information item indicating one of combinations of beam-selection vectors; and transmitting signals by multi-stage precoding using a first precoding matrix corresponding to the received first channel state information item and a second precoding matrix corresponding to the received second channel state information item. The combinations of beam selection vectors include a combination of either a first beam-forming vector or a second beam-forming vector, and either a third beam-forming vector or a fourth beam-forming vector, among the four beam-forming vectors, and selectively include one of: either a combination of beam selection vectors for repeatedly selecting the first beam-forming vector or a combination of beam selection vectors for repeatedly selecting the third beam-forming vector; either a combination of beam selection vectors for repeatedly selecting the second beam-forming vector or a combination of beam selection vectors for repeatedly selecting the fourth beam-forming vector; and a combination of beam selection vectors for selecting the first beam-forming vector and the second beam-forming vector, or a combination of beam selection vectors for selecting the third beam-forming vector and the fourth beam-forming vector. |
