De Beer, Dirk JohannesJoubert, Trudi-Heleen2026-02-242026-02-242026-02D.J. De Beer and T.-H. Joubert, "Level-Crossing Downsampling for Quantization Error Reduction in Sine Wave Estimation," in IEEE Transactions on Instrumentation and Measurement, vol. 75, pp. 1-8, 2026, Art no. 6504008, doi: 10.1109/TIM.2026.3660436.0018-9456 (print)1557-9662 (online)10.1109/TIM.2026.3660436http://hdl.handle.net/2263/108612This work introduces a digital postprocessing algorithm—level-crossing downsampling (LC-DS)—for estimating sine wave parameters from sequences of quantized values acquired by standard ADCs. LC-DS emulates level-crossing sampling by retaining only transition points, reducing correlated quantization error, and accelerating least-squares regression (LSR). Its performance is benchmarked against uniform LSR and calibrated sinefit to highlight accuracy and computational tradeoffs. Across a wide dynamic range, LC-DS consistently outperforms uniform sampling and approaches the accuracy of calibrated sinefit for low-level signals, while remaining up to two orders of magnitude faster for large datasets. Unlike conventional methods, LC-DS scales efficiently with data size, enabling real-time estimation without hardware modifications. Practical and simulated experiments, including electrochemical impedance spectroscopy, confirm robustness under conditions such as signal saturation. These results position LC-DS as a compelling alternative for applications requiring both high precision and computational efficiency.en© 2026 IEEE - All rights reserved, including rights for text and data mining and training of artificial intelligence and similar technologies.Quantization (signal)AccuracyEstimationDiscrete Fourier transformsFrequency estimationStandardsSignal resolutionReal-time systemsNoiseImpedance measurementElectrochemical impedance spectroscopyLeast-squares regression (LSR)Real-time signal processingSine wave estimationLevel-crossing downsampling (LC-DS)Postprint Article