QUALCOMM Incorporated
Listen-before-talk and channel reservation for millimeter wave systems

Abstract:

Methods, systems, and devices for wireless communications are described. A method may include receiving, from a base station, a pre-grant message indicating that a downlink transmission is available for transmission to a user equipment (UE) on a first radio frequency (RF) spectrum band, and performing a listen-before-talk (LBT) procedure. The UE may then transmit, based on the LBT procedure indicating a clear channel, a channel reservation signal on a second RF spectrum band, and transmit, to the base station, a response to the pre-grant message on the second RF spectrum band. Another method may include a base station transmitting a pre-grant message to the UE, and receiving a response to the pre-grant message on a second RF spectrum band. The base station may then transmit the downlink transmission to the UE using one or more of a set of transmit beams on a first RF spectrum band.