A method includes: a transmit end transmits at least two mixed pilot signals to a receive end separately by using at least two physical antennas. The at least two mixed pilot signals are separately obtained after preset pilot signals corresponding to logical antennas in the at least two logical antennas are weighted by using a precoding weight matrix. The transmit sends a first codebook subset restriction instruction to the receive end. The first codebook subset restriction instruction carries a rank indication RANK and at least one precoding matrix index PMI. The transmit end receives a channel quality feedback message that is fed back by the receive end according to downlink channel quality of an equivalent channel of a specified antenna. Accordingly, a suitable serving antenna is selected for a receive end, thereby improving signal quality.