Mud pulse telemetry devices, systems, and methods

Devices, systems and methods for transmitting downhole data are provided. The devices include a rotor-stator modulator configured for use in a drill string, and a drive and control system configured to drive the rotor according to a modulation scheme resulting in both oscillating and full rotational movement. The modulation scheme can comprise a trajectory algorithm such as a QAM trajectory algorithm. The systems include a modulator disposed within a drill string which creates modulated pulses according to an algorithm providing for both oscillating and full rotational movement of the rotor, and may also include a demodulator. The methods include transmitting coded data by driving a rotor relative a stator disposed in a drill string according to a modulation scheme that provides both oscillating and full rotational movement and results in modulated mud pulses representative of data recorded downhole, and may involve decoding the data.