An apparatus and method for transmitting signals in a wireless communication system are provided. The apparatus includes N antennas, a processor coupled to the N antennas and configured to generate N transmit signals by performing precoding on R spatial streams for R spatial layers, and to transmit the N transmit signals respectively through the N antennas, wherein an information stream, a reference signal sequence, and a reference signal pattern are allocated to each of the R spatial layers, and the reference signal pattern is a time-frequency resource pattern used for transmission of the reference signal sequence, wherein each of the R spatial streams corresponds to one spatial layer, and wherein each of the R spatial streams is generated based on the information stream, reference signal sequence, and reference signal pattern allocated to a corresponding spatial layer.