Technology for decreasing latency for contention based scheduling request (SR) transmission is disclosed. A user equipment (UE) can process, for transmission to an enhanced node B (eNB), a DeModulation Reference Signal (DM-RS) that is randomly selected from a set of configured DM-RS sequences or configured by the eNB. The UE can select an SR transmission resource as a function of a DM-RS sequence index or cell identification (ID) based on a predefined mapping rule. The UE can process, for transmission to the eNB, a SR message having a buffer status report (BSR) and UE identification (UE-ID) information on the selected SR transmission resource.