Patent ID: 8526384

Claim:
A method of transmitting channel state information (CSI) feedback by a receiver to a transmitter in a wireless communication system, the method comprising: mapping upper triangle components r x,y (i,k) of a channel covariance matrix R(i,k), where x≦y, to constellation points; allocating the mapped upper triangle components to a resource; and transmitting the mapped upper triangle components as the CSI feedback using the allocated resource, wherein R ⁡ ( i , k ) = [ r 1 , 1 ⁡ ( i , k ) r 1 , 2 ⁡ ( i , k ) … r 1 , N ⁡ ( i , k ) r 2 , 1 ⁡ ( i , k ) r 2 , 2 ⁡ ( i , k ) … r 2 , N ⁡ ( i , k ) ⋮ ⋮ ⋱ ⋮ r N , 1 ⁡ ( i , k ) r N , 2 ⁡ ( i , k ) … r N , N ⁡ ( i , k ) ] , where N is a number of antennas at the transmitter, i is a symbol index, and k is a subcarrier index.