Wireless communications systems and methods related to uplink (UL) communications in a wireless network are provided. In some instances, a wireless communication device is configured to: transmit, to a second wireless communication device, a transmission grant indicating a transmission period; transmit a configuration indicating a plurality of reference signal symbols within the transmission period and an association between a plurality of starting locations and the plurality of reference signal symbols; monitor, in response to the transmission grant, for a communication signal from the second wireless communication device in the transmission period; and identify, upon detection of the communication signal, a starting location of the communication signal from among the plurality of starting locations within the transmission period.