Patent ID: 8675766

Claim:
A method of transmitting pilot signals by a transmitter in a multiple-input multiple-output (MIMO) antenna system using an orthogonal frequency division multiplexing (OFDM) scheme, the method comprising: allocating a first pilot P 1 for a first antenna, a second pilot P 2 for a second antenna, a third pilot P 3 for a third antenna and a fourth pilot P 4 for a fourth antenna to each of a plurality of OFDM symbols in a basic resource block comprising the plurality of OFDM symbols in a time domain and a plurality of subcarriers in a frequency domain; and transmitting the first, second, third, and fourth pilots P 1 to P 4 to a receiver, wherein the first, second, third, and fourth pilots P 1 to P 4 are allocated to two consecutive subcarriers in two consecutive OFDM symbols of the basic resource block to be a first pattern according to Table 1 or a second pattern according to Table 2: TABLE 1 even numbered odd numbered OFDM symbol OFDM symbol Subcarrier k P1 P2 Subcarrier k + 1 P3 P4 and TABLE 2 even numbered odd numbered OFDM symbol OFDM symbol Subcarrier k P2 P1 Subcarrier k + 1 P4 P3, wherein k is a subcarrier index, and wherein the first pattern and the second pattern alternate with each other along the frequency domain in the two consecutive OFDM symbols.