An on-demand scheduling request (SR) design is disclosed. Such an on-demand or triggered SR operation provides pre-configuration of user equipments (UEs) with triggered SR resources. Base stations may also configure UEs to monitor for a trigger signal within a bit field of control signaling from the base station. Upon detecting the trigger signal within such bit field, the UEs may use the triggered SR resources for transmitting triggered SR requests. Such use of the triggered SR resources may be in response to UEs detected cancelation of other periodic configured SR resources.