Uplink spectrum efficiency

Methods and systems are disclosed for reducing control signaling in uplink transmissions. A device, such as a wireless transmit/receive unit, may determine to use a demodulation reference signal (DM-RS) transmission schedule out of a plurality of DM-RS transmission schedules. The DM-RS transmission schedule may be characterized by a DM-RS transmission being mapped to a single orthogonal frequency-division multiplexing (OFDM) symbol per subframe of a data stream. The DM-RS transmission schedule may be characterized by a DM-RS transmission being mapped to a first subset of subcarriers of an OFDM symbol of a subframe of a data stream and Physical Uplink Shared Channel (PUSCH) transmission or Physical Uplink Control Channel (PUCCH) control information being mapped to a second set of subcarriers of the OFDM symbol. The first set of subcarriers may be different than the second set of subcarriers. The data stream may be transmitted according to the DM-RS transmission schedule.