SECONDARY TIMING ADVANCE GROUPS WITH ONLY LICENSE ASSISTED ACCESS SECONDARY CELLS

Methods, systems, and devices for wireless communication are described. A wireless system may support efficient techniques for adding license assisted access (LAA) secondary cells (SCells) to a secondary timing advance group (sTAG). For example, a base station may determine whether to add an LAA SCell to an sTAG based on whether the LAA SCell is a scheduling carrier for user equipment (UE). That is, the base station may determine whether to add an LAA SCell to an sTAG based on whether UE scheduled to communicate over the LAA SCell is self-scheduled over the LAA SCell or cross-carrier scheduledover another cell. As such, the wireless system may improve the likelihood that UE may receive a downlink transmission over an LAA SCell in an sTAG that the UE may use to determine a downlink timingreference for an uplink transmission over the LAA SCell. 描述了用于无线通信的方法、系统和设备。无线系统可以支持用于将执照辅助接入(LAA)副蜂窝小区(SCell)添加到副定时提前群(sTAG)的高效技术。例如，基站可以基于LAA SCell是否是用于用户装备(UE)的调度载波来确定是否要将该LAA SCell添加到sTAG。即，基站可以基于被调度在LAA SCell上通信的UE是在该LAA