Channel access method and apparatus
A channel access method is provided. Under the method, a network element performs random backoff listen before talk (LBT) for channel preemption, and after the preemption succeeds, performs signal transmission in the first transmission time interval TTI within a maximum channel occupancy time MCOT. The network element also performs nonrandom backoff LBT for channel preemption before another at least one TTI within the maximum channel occupancy time MCOT. This is to ensure coexistence and performance of systems when an LBT requirement of a high unlicensed frequency band is met.
1. A channel access method, comprising:
performing, by a network element, a random backoff listen before talk (LBT) for channel preemption;
after the channel preemption succeeds, performing, a signal transmission in the first transmission time interval (TTI) within a maximum channel occupancy time (MCOT); and
performing, by the network element before another at least one TTI within the MCOT, non-random backoff LBT for channel preemption.
2. The method according to claim 1 , wherein the random backoff LBT comprises an omnidirectional random backoff LBT or a directional random backoff LBT, and the signal transmission in the first TTI comprises a directional signal transmission.
3. The method according to claim 1 , wherein the non-random backoff LBT comprises a directional non-random backoff LBT, and a signal transmission in a TTI after the directional non-random backoff LBT comprises a directional signal transmission.
4. The method according to claim 3 , wherein a direction of the directional non-random backoff LBT is the same as a beam direction of the signal transmission performed in the TTI after the directional non=random backoff LBT.
5. A channel access method, comprising:
performing, by a first network element, a random backoff LBT for channel preemption; and
after the channel preemption succeeds, notifying, by the first network element in at least one transmission time interval (TTI) within a MCOT, a second network element of frame structure information of a set of corresponding TTIs to enable the second network element to perform a directional signal transmission in the set of corresponding TTIs.
6. The method according to claim 5 , wherein the frame structure information of the set of corresponding TTIs comprises information indicating whether the set of corresponding TTIs comprises an LBT gap.
7. The method according to claim 5 , wherein the set of corresponding TTIs comprises a plurality of consecutive TTIs, the frame structure information of the set of corresponding TTIs comprises information indicating at least one of the following:
the last TTI within the MCOT comprises an LBT gap, but other TTIs within the MCOT do not comprise an LBT gap;
only the last TTI within the MCOT comprises an LBT gap; or
information about a quantity or a length of the plurality of consecutive TTIs.
8. The method according to claim 5 , further comprising:
performing, by the first network element before another at least one TTI within the MCOT, a non-random backoff LBT for channel preemption.
9. A channel access apparatus, comprising:
a processor, configured to perform a random backoff listen before talk (LBT) for channel preemption; and
a transceiver, configured to perform, after the channel preemption succeeds, a signal transmission in the first TTI within a MCOT, wherein
the processor is further configured to perform, before another at least one TTI within the MCOT, a non-random backoff LBT for channel preemption.
10. The apparatus according to claim 9 , wherein the random backoff LBT comprises an omnidirectional random backoff LBT or a directional random backoff LBT, and the signal transmission in the first TTI comprises a directional signal transmission.
11. The apparatus according to claim 9 , wherein the non-random backoff LBT comprises a directional non-random backoff LBT, and a signal transmission in a TTI after the directional non-random backoff LBT comprises directional signal transmission.
12. The apparatus according to claim 11 , wherein a direction of the directional non-random backoff LBT is the same as a beam direction of the signal transmission performed in the TTI after the directional non-random backoff LBT.
13. A channel access apparatus, comprising:
a processor, configured to perform a random backoff listen before talk (LBT) for channel preemption; and
a transceiver, configured to notify, in at least one transmission time interval (TTI) within a maximum channel occupancy time (MCOT) after the preemption succeeds, a network element of frame structure information of a set of corresponding TTIs to enable the network element to perform a directional signal transmission in the set of corresponding TTI.
14. The apparatus according to claim 13 , wherein the frame structure information of the set of corresponding TTIs comprises information indicating: whether the corresponding TTI comprises an LBT gap.
15. The apparatus according to claim 13 , wherein the set of corresponding TTI comprises a plurality of consecutive TTIs, the frame structure information of the set of corresponding TTIs comprises at least one of the following:
the last TTI within the MCOT comprises an LBT gap, but other TTIs within the MCOT do not comprise an LBT gap;
only the last TTI within the MCOT comprises an LBT gap; or information about a quantity or a length of the plurality of consecutive TTIs.
16. The apparatus according to claim 13 , the processor is further configured to: perform a non-random backoff LBT for channel preemption before another at least one TTI within the MCOT.