Methods, systems, and devices for wireless communication are described. The methods, systems, and devices may include receiving control information from a serving station, synchronizing with an end device based at least in part on the control information received from the serving station, and receiving an acknowledgement (ACK) from the end device in response to the synchronizing, the ACK indicating the end device is synchronized with the relay device. The methods, systems, and devices may also include receiving a data packet from the end device subsequent to the synchronizing, and transmitting, to the serving station, the data packet received from the end device, the transmitting based at least in part on the control information received from the serving station.