Patent ID: 9559763
Date: 2017-01-31
CPC Classifications: H04B,H04L

Claim:
1. A method of controlling the polarization state of signals to be transmitted from a MIMO capable radio base station node of a cell to a plurality of user equipment, said radio base station node comprising a precoder unit connecting a first and a second virtual antenna port to a respective first and second transmit antenna port, the method comprising: controlling a relative phase between transmitted signals from said first transmit antenna port and said second transmit antenna port to provide a predetermined pair of orthogonal polarization states for signals transmitted on said first and said second virtual antenna ports; and interchanging the polarization states of said first and second virtual antenna ports by adapting said relative phase between said transmitted signals continuously in time, to provide transmitted polarized signals with alternating polarization states, wherein said base station node is configured with a plurality of carriers covering a same sector and said polarization states are interchanged between at least two of said carriers in the frequency domain.