Memoryless Continuous-Phase Chirp Spread Spectrum for Mud Pulse Telemetry

Measurement while drilling (MWD) is essential for advancing deepwater oil and gas exploration, with mud pulse telemetry (MPT) standing out for its broad applicability and reliability. However, the strong pump noise and the reduced signal amplitude introduced by the continuous wave generators present challenges for high data rate MPT applications. This paper presents a novel modulation technique, memoryless continuous-phase chirp spread spectrum (MCPCSS), designed to address these issues. MCPCSS satisfies the continuous-phase requirement while leveraging spread spectrum techniques to counteract line-spectrum pump noise. Simulations with on-site pump noise demonstrate that MCPCSS achieves a symbol error rate of 0 at a signal-to-white-noise ratio of -4 dB and a signal-to-pump-noise ratio of -13.4 dB, significantly improving transmission reliability under strong pump noise and multiple-pump conditions.