Patent ID: 8687721

Claim:
A method for selecting a user in a communication system including a base station having M antennas and K users having one receive antenna, comprising: (a) calculating channel orthogonality between each possible user and previously selected users; and (b) selecting user having a largest channel orthogonality calculated; wherein said calculation uses an equation: Î² k = âˆ i = 1 k â¢ â¢ ï˜… h i ï˜† 2 det â¡ [ HH * ] , H = [ h 1 T â¢ ï˜ƒ â¢ â€¦ â¢ ï˜„ â¢ h k - 1 T ] T , and said selecting uses an equation: Ï€ â¡ ( i ) = arg â¢ â¢ min k âˆˆ Ui â¢ ï˜… Î² k ï˜† S c â†S c âˆª{Ï€( i )}, where i represents an order of algorithm performance, h is a channel vector of one user selected among the possible users, H represents a channel matrix formed of channels of previously selected kâˆ’1 users, S represents selected user groups, and Ï€(i) represents a user number selected as i-th.