公开(公告)号：US20190230665A1

公开(公告)日：2019-07-25

申请号：US16340938

申请日：2017-10-12

Applicant: Nokia Technologies Oy

Inventor： David Lopez-Perez ,  Lorenzo Galati Giordano ,  Giovanni Geraci ,  Andrea Bonfante

IPC: H04W72/04

Abstract: A multiple input multiple output network node, an access network node, a computer program and method are disclosed. The method comprises prior to transmitting signals in an unlicensed band: estimating at least one channel within the unlicensed band between at least one access network node operable to transmit in the unlicensed band and the multiple input multiple output network node; determining precoding operations required to generate a null signal beam for the at least one estimated channel; monitoring the unlicensed band using the determined precoding operations. In response to detecting the unlicensed band to be clear of signals: transmitting at least one signal in the unlicensed band with the null beam in place such that no signal is transmitted on the at least one estimated channel.