Adaptive beam selection in a wireless communication system

A radio network node for downlink signal transmission to a user equipment over an adaptively selected beam, the radio network node comprising:

• processing circuitry;
• memory containing instructions executable by the processing circuitry whereby the radio network node is operative to:
• transmit, over different beams, different beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the different beam selection signals comprise uplink grants that assign the user equipment the different uplink radio resources for uplink transmission, the beam selection signal serving a dual purpose of uplink grant and adaptive beam selection wherein transmitting the different beam selection signals comprises transmitting the different beam selection signals over the different beams in a randomly ordered sequence;
• receive, from the user equipment, a response over a responsive radio resource of the uplink radio resources;
• select, from the different beams, a beam over which a beam selection signal configured to prompt a response on the responsive uplink radio resource is transmitted;
• and
• transmit a downlink signal to the user equipment over the selected beam.

A non-transitory computer readable recording medium storing a computer program product for controlling a radio network node for downlink signal transmission to a user equipment over an adaptively selected beam, the computer program product comprising software instructions which, when run on processing circuitry of the radio network node, causes the radio network node to:

• transmit, over different beams, different beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the different beam selection signals comprise uplink grants that assign the user equipment the different uplink radio resources for uplink transmission, the beam selection signal serving a dual purpose of uplink grant and adaptive beam selection, wherein transmitting the different beam selection signals comprises transmitting the different beam selection signals over the different beams in a randomly ordered sequence;
• receive, from the user equipment, a response over a responsive radio resource of the uplink radio resources;
• select, from the different beams, a beam over which a beam selection signal configured to prompt a response on the responsive uplink radio resource is transmitted;
• and
• transmit a downlink signal to the user equipment over the selected beam.