Port-to-beam pre-coding to enable codebook based MU-MIMO operation in active antenna systems

[0027] discussed below Figure 1 to Figure 10 The various examples and examples used to describe the principles of the invention are by way of illustration only and should not be construed in any way as limiting the scope of the invention. Those skilled in the art will understand that the principles of the invention may be implemented in any suitably arranged wireless system.

[0028] The downlink of a wireless system includes a base station (BS) for transmitting data to a number of UEs located within the coverage of the base station. A base station seeks to increase the capacity experienced by all UEs within its coverage area through various techniques such as intelligent resource scheduling, spatial multiplexing using multiple antennas, and precoding data streams to eliminate inter-stream interference. like image 3 and Figure 4 As shown, the base station comprises a baseband unit (BBU) 1 and a remote radio head (RRH) 2 or 3 . The BBU is responsible for the digital process