Patent ID: 8842639

Claim:
A method for transmitting a pilot signal in a downlink Multiple-Input Multiple-Output (MIMO) system supporting a maximum M transmission antennas, the method comprising: mapping, by a Base Station (BS), cell-specific pilot symbols for transmission antenna ports R 0 ′ to R(N−1)′ to a first region of a subframe; mapping, by the BS, User Equipment-specific (UE-specific) pilot symbols for transmission antenna ports R 0 to R(M−1) to a second region of the subframe, wherein N<M; and transmitting the subframe to which the cell-specific pilot symbols and the UE-specific pilot symbols are mapped, wherein each of the first and the second regions of the subframe includes a prescribed number of consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols on a time domain.