Beam-Based Listen-Before-Talk for mmWave Coexistence

The patent segments the omnidirectional LBT procedure into multiple directional beam-based LBT procedures. Instead of performing a single omnidirectional channel access check, the system divides the channel access into multiple directional beams, each performing its own LBT procedure. This segmentation allows each beam to independently assess channel availability in its specific direction, resolving the hidden/exposed node problems while maintaining coexistence fairness with other unlicensed band users.

The patent performs preliminary LBT procedures on each directional beam before actual data transmission. By conducting channel access checks in advance on each narrow beam, the system ensures that transmissions only proceed when the channel is clear in that specific direction. This preliminary action maintains channel access reliability while enabling the benefits of narrow beam spatial multiplexing.

The patent changes the parameter of LBT procedure from omnidirectional to directional beam-based operations. By modifying the spatial parameter of channel access from a single omnidirectional check to multiple directional checks, the system enhances coexistence fairness and reduces power consumption through more targeted transmissions. The complexity increase is managed by systematically organizing these parameter changes across multiple beams with coordinated timing.