Method of transmitting signals for multiple antenna system

A method of transmitting signals in a multi-antenna system, the method comprising:

• generating a space-time code (STC) which performs an interleaving operation and a phase shift operation on acquired signals, wherein the space-time code is generated for N antennas and M time slots;
• performing a coding of the acquired signals using the generated space-time code;
• and
• transmitting the coded signals via a plurality of antennas,
• wherein the space-time code is represented as a matrix having N rows and M columns, and
• wherein the space-time code includes a matrix CNew4×1 as denoted by equation:
• C
• New
• 4
• ×
• 1
• =
• (
• x
• ~
• 1
• x
• ~
• 2
• ⁢
• ⅇ
• j
• ⁢
• ⁢
• θ
• r
• ⁢
• ⁢
• 1
• 0
• 0
• x
• ~
• 4
• ⁢
• ⅇ
• j
• ⁢
• ⁢
• θ
• r
• ⁢
• ⁢
• 2
• x
• ~
• 3
• 0
• 0
• 0
• 0
• x
• ~
• 1
• x
• ~
• 2
• ⁢
• ⅇ
• j
• ⁢
• ⁢
• θ
• r
• ⁢
• ⁢
• 1
• 0
• 0
• x
• ~
• 4
• ⁢
• ⅇ
• j
• ⁢
• ⁢
• θ
• r
• ⁢
• ⁢
• 2
• x
• ~
• 3
• )
• ,
• where {tilde over (x)}1=x1Real+jx3imaginary, {tilde over (x)}2=x2Real+jx4imaginary, {tilde over (x)}3=x3Real+jx1imaginary, and {tilde over (x)}4=x4Real+jx2imaginary,
• where xiReal is indicative of a real part of xi (i=1, . . . , 4),
• where xiimaginary is indicative of an imaginary part of xi (i=1, . . . , 4),
• where xi (i=1, . . . , 4) is indicative of Siejθ (i=1, . . . , 4), as denoted by xi=siejθ, i=1, . . . , 4
• where si, i=1, . . . , 4 is indicative of a data symbol having a complex value, and θr1 and θr2 are indicative of phase-shifted angles,
• wherein N is 4, and M is 4.