1. A communication method of a receiver, the communication method comprising: calculating an eigenvector matrix comprising eigenvectors of a channel matrix or a channel covariance matrix; generating a codebook for each eigenvector of the eigenvector matrix such that each codebook has a different size based on eigenvalues of the channel matrix or the channel covariance matrix; quantizing each of the eigenvectors using the respective codebook for each eigenvector; and transmitting, to a transmitter, information associated with each of the quantized eigenvectors.