Per-User Unitary Rate Control (PU<sup>2</sup>RC) is a multi-user MIMO scheme. PU2RC utilizes both transmission pre-coding and multi-user scheduling. By doing that, the network capacity is further enhanced that the capacity of the single-user MIMO scheme.
-* Background technologies: A single-user MIMO was initially developed to improve the spectral efficiency of point-to-point wireless transmission link. A multi-user MIMO was developed for cellular systems where the base station simultaneously communicates with multiple users.
-* Principle: The concept of Per-User Unitary Rate Control (PU<sup>2</sup>RC) was proposed in [http://www.google.com/patents/about?id=lpWnAAAAEBAJ&dq=7,324,480 US Patent No. 7,324,480, ''Mobile communication apparatus and method including base station and mobile station having multi-antenna''] by James S. Kim, Kwang Bok Lee, Kiho Kim and Changsoon Park.
Recently, PU<sup>2</sup>RC has been adopted in the IEEE 802.16m system description documentation (SDD) and the concept of this scheme was included in 3GPP [[3GPP Long Term Evolution|LTE]] standard.
