Methods, systems, and devices for wireless communications are described that provide improved repetition techniques for autonomous uplink transmissions. Configuration information may be provided from a base station to a user equipment (UE) for autonomous uplink transmissions, that may indicate initial resources for an initial uplink transmission slot and retransmission resources for a number of retransmissions. Time resources within the retransmission resources may be configured to provide enhanced reliability, such as by being configured in non-contiguous slots to avoid one or more other transmission channels. Time resources within slots may also be configured to prevent persistent collisions with autonomous uplink transmissions or retransmissions of two or more different UEs.