Methods and devices for determining suitable transmit directions for beamformed transmission

A method performed by a wireless device for determining beam directions to use for communication between the wireless device and a radio base station, the wireless device and the radio base station being connected through an existing radio link, wherein the method comprising:

• transmitting a message over the existing radio link to trigger the radio base station to perform beam scan;
• transmitting according to a pre-determined transmission scheme, tracking beams in different transmit directions for the radio base station to perform the beam scan to detect a transmitted tracking beam;
• receiving information relating to the outcome of the performed beam scan from the radio base station over the existing radio link;
• and
• determining, based on the received information, a transmit direction to use for beamformed transmissions to the radio base station.

A transmitting communication unit for determining beam directions to use for communication between the transmitting communication unit and a receiving communication unit that have an existing radio link, the transmitting communication unit comprising:

• a processor;
• and
• a memory, the memory comprising instructions which, when executed by the processor, cause the transmitting communication link to:
• transmit a message over the existing radio link to trigger the receiving communication unit to perform a beam scan;
• transmit, according to a pre-determined transmission scheme, tracking beams in different transmit directions for the receiving communication unit to perform the beam scan to detect a transmitted tracking beam;
• receive information relating to the outcome of the performed beam scan from the receiving communication unit over the existing radio link;
• and
• determine, based on the received information, a transmit direction to use for beamformed transmissions to the receiving communication unit.

A beam scanning method performed by a radio base station to enable determination of beam directions to use for communication between the radio base station and a wireless device, the radio base station and the wireless device being connected through an existing radio link, wherein the method comprising:

• triggering, by a message transmitted over the existing radio link, the wireless device to perform a transmission of tracking beams;
• performing a beam scan in order to detect tracking beams transmitted by the wireless device;
• collecting information relating to the outcome of the performed beam scan, the information to enable the wireless device to identify at least one transmit direction corresponding to a detected tracking beam;
• and
• transmitting the collected information to the wireless device over the existing radio link.