1 . A method of operating a first communication device in a communications network that includes a second communication device, the method comprising: transmitting (202, 730) a first beamformed signal toward the second communication device using a first beam; responsive to transmitting the first beamformed signal, receiving (204, 740) a feedback signal, wherein receiving the feedback signal comprises receiving hybrid automatic repeat request, HARQ, feedback from the second communication device during a physical sidelink feedback channel, PSFCH, occasion which is specific to the first beamformed signal; and determining (206, 750) to use a second beam in sidelink communication with the second communication device based on the feedback signal.

2. The method of claim 1 , wherein transmitting the first beamformed signal comprises transmitting a first plurality of beamformed signals toward the second communication device, wherein the first plurality of beamformed signals comprises the first beamformed signal.

3. The method of claim 2, wherein each beamformed signal of the first plurality of beamformed signals is associated with a different beam of a plurality of beams.

4. The method of claim 3, wherein transmitting the first plurality of beamformed signals toward the second communication device comprises sweeping across the plurality of beams.

5. The method of any of claims 2-3, wherein transmitting the first plurality of beamformed signals toward the second communication device comprises simultaneously transmitting the first plurality of beamformed signals toward the second communication device.

6. The method of any of claims 2-5, wherein transmitting the first plurality of beamformed signals comprises at least one of:

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AMENDED SHEET (ARTICLE 19) periodically transmitting each beamformed signal of the first plurality of beamformed signals; and repeatedly transmitting each beamformed signal of the first plurality of beamformed signals a predetermined number of times.

7. The method of any of claims 2-6, wherein: each beamformed signal of the first plurality of beamformed signals includes different data; and/or some beamformed signals of the first plurality of beamformed signals are generated using different modulation and coding schemes.

8. The method of any of claims 2-7, wherein: receiving the feedback signal comprises receiving an indication of feedback associated with each beamformed signal of the first plurality of beamformed signals at different frequencies resources and/or code domains within a feedback occasion; and/or determining to use the second beam comprises determining the second beam based on the feedback signal including an acknowledgement, ACK, associated with a second beamformed signal of the first plurality of beamformed signals that used the second beam.

9. The method of any of claims 2-8, wherein the second beam is a narrower beam than the first beam and within an envelope of the first beam, and wherein determining to use the second beam comprises: determining that the first feedback signal includes an acknowledgement, ACK, of the first beamformed signal; transmitting a second beamformed signal using the second beam toward the second communication device; responsive to transmitting the second beamformed signal, receiving a second feedback signal; and determining that the second feedback signal associated with the second beamformed signal indicates the second beam is suitable for sidelink transmissions from the first communication device to the second communication device.

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10. The method of claim 9, wherein: determining that the second feedback signal indicates the second beam is suitable comprises determining that the second feedback signal includes an ACK of the second beamformed signal; or the second feedback signal includes an indication of measurements of channel state information, CSI, associated with the second beamformed signal, and determining that the second feedback signal indicates the second beam is suitable comprises determining that the second feedback signal indicates the measurements of the CSI exceeds a threshold value and/or exceeds measurements of CSI associated with another beamformed signal.

11 . The method of claims 9 or 10, wherein the second beam is a first narrow beam, wherein transmitting the second beamformed signal comprises transmitting a second plurality of beamformed signals, each beamformed signal of the second plurality of beamformed signals using a narrower beam than the first beam that is within an envelope of the first beam, and wherein receiving the second feedback signal comprises receiving a negative acknowledgment, NACK or an absence of expected feedback associated with a third beamformed signal of the second plurality of beamformed signals that is different than the second beamformed signal.

12. The method of any of claims 2-8, wherein determining to use the second beam comprises, subsequent to transmitting the first plurality of beamformed signals, determining that the feedback signal does not include an acknowledgement associated with one of the beamformed signals of the first plurality of beamformed signals and that the feedback signal includes a negative acknowledgment, NACK, associated with a second beamformed signal of the first plurality of beamformed signals that used the second beam.

13. The method of claims 12, wherein the NACK associated with the second beamformed signal was the first or the last NACK included in the feedback signal.

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14. The method of any of claims 1-8, 12 or 13, wherein receiving the feedback signal comprises receiving an indication of a negative acknowledgement, NACK, of the first beamformed signal or an absence of expected feedback associated with the first beamformed signal, wherein determining to use the second beam comprises: transmitting a second beamformed signal toward the second communication device using the second beam, the second beam being different than the first beam; responsive to transmitting the second beamformed signal, receiving a second feedback signal; and determining to use the second beam based on the second feedback signal.

15. The method of any of claims 1 -14, further comprising: establishing (710) sidelink communication between the first communication device and the second communication device; and communicating (720) configuration information with the second communication device.

16. The method of claim 15, wherein the configuration information comprises at least one of: a number of beamformed signals to be transmitted by the first communication device; and a timing of the feedback signal.

17. The method of any of claims 1 -16, further comprising: transmitting (760) an indication of the second beam to the second communication device; and/or transmitting (770) a third plurality of beamformed signals toward the second communication device using the second beam; and responsive to transmitting the third plurality of beamformed signals, receiving (780) an indication of a third beam from the second communication device and an indication that the second communication device will use the third beam to receive

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AMENDED SHEET (ARTICLE 19) subsequent sidelink communication from the first communication device.

18. The method of any of claims 1 -17, wherein the first beamformed signal is a first wide beamformed signal of a plurality of wide beamformed signals and the first beam is a first wide beam, the method further comprising: prior to transmitting the first beamformed signal, transmitting (722) a second wide beamformed signal of the plurality of wide beamformed signals toward the second communication device using a second wide beam; and subsequent to transmitting the second wide beamformed signal, transmitting (724) one or more narrow beamformed signals toward the second communication device, each narrow beamformed signal of the one or more narrow beamformed signals using one of a plurality of narrow beams that are each narrower than the second wide beam and within an envelope of the second wide beam, wherein transmitting the first beamformed signal comprises, transmitting the first beamformed signal in response to one of: not receiving (726) a threshold amount of feedback associated with the one or more narrow beamformed signals within a predetermined amount of time; and receiving (726) a threshold number of negative acknowledgments, NACKs, associated with the one or more narrow beamformed signals.

19. The method of any of claims 1 -18, wherein the first communication device and/or the second communication device are vehicles.

20. A method of operating a first communication device in a communications network that includes a second communication device, the method comprising: receiving (302, 830) a first beamformed signal from the second communication device; responsive to receiving the first beamformed signal, determining (304, 840) feedback associated with the first beamformed signal based on an ability of the first communication device to decode the first beamformed signal; and transmitting (306, 850) the feedback to the second communication device, wherein transmitting the feedback comprises transmitting hybrid automatic repeat

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AMENDED SHEET (ARTICLE 19) request, HARQ, feedback during a physical sidelink feedback channel, PSFCH, occasion which is specific to the first beamformed signal.

21 . The method of claim 20, wherein receiving the first beamformed signal comprises receiving a plurality of beamformed signals from the second communication device, wherein the plurality of beamformed signals comprises the first beamformed signal.

22. The method of claim 21 , wherein each beamformed signal of the plurality of beamformed signals includes different data.

23. The method of any of claims 21 -22, wherein transmitting the feedback comprises transmitting feedback associated with each beamformed signal of the plurality of beamformed signals at different frequencies during a feedback occasion.

24. The method of any of claims 20-23, wherein: determining the feedback comprises determining that the feedback includes one of: an acknowledgment, ACK, in response to being able to decode sidelink control information, SCI, and data from the first beamformed signal; a negative acknowledgment, NACK, in response to being able to decode the SCI and failing to decode the data from the first beamformed signal; and an absence of expected feedback in response to failing to decode the SCI; or determining the feedback comprises determining a channel state information, CSI, based on the first beamformed signal.

25. The method of any of claims 20-24, wherein transmitting the HARQ feedback comprises: transmitting the HARQ feedback toward the second communication device using an omnidirectional transmission; transmitting the HARQ feedback using a transmission, Tx, beam derived from a reception, Rx, beam used to receive the first beamformed signal from the second

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AMENDED SHEET (ARTICLE 19) communication device; or transmitting the HARQ feedback using a predetermined HARQ process identifier associated with the first beamformed signal.

26. The method of any of claims 20-25, further comprising: establishing (810) sidelink communication between the first communication device and the second communication device; and communicating (820) configuration information with the second communication device.

27. The method of claim 26, wherein the configuration information comprises at least one of: a number of beamformed signals to be transmitted by the second communication device; and a timing of the feedback.

28. The method of any of claims 20-27, further comprising: responsive to transmitting the feedback, receiving (860) an indication of a transmission, Tx, beam from the second communication device and an indication that the second communication device will use the beam to transmit subsequent sidelink communication to the first communication device.

29. The method of any of claims 20-28, the method further comprising: receiving (870) a plurality of second beamformed signals from the second communication device using a plurality of beams; determining (875) to use a beam of the plurality of beams to receive subsequent sidelink communication from the second communication device; and transmitting (880) an indication of the beam to the second communication device and an indication that the first communication device will use the beam to receive subsequent sidelink communication from the second communication device.

30. The method of any of claims 20-29, wherein the first communication device and/or the second communication device are vehicles.

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31 . A first communication device (1200) operating in a communications network, the first communication device comprising: processing circuitry (1202) configured to operate in accordance with any of claims 1-19 and/or claims 20-30.

32. A computer program comprising program code to be executed by processing circuitry (1202) of a first communication device (1200) operating in a communications network, whereby execution of the program code causes the first communication device to operate in accordance with any of claims 1-19 and/or claims 20-30.

33. A computer program product comprising a non-transitory storage medium (1210) including program code to be executed by processing circuitry (1202) of a first communication device (1200) operating in a communications network, whereby execution of the program code causes the first communication device to operate in accordance with any of claims 1 -19 and/or claims 20-30.

34. A non-transitory computer-readable medium having instructions stored therein that are executable by processing circuitry (1202) of a first communication device (1200) operating in a communications network to cause the first communication device to operate in accordance with any of claims 1-19 and/or claims 20-30.

AMENDED SHEET (ARTICLE 19)