A Method for Measuring Signals from 0.001Hz to 1Hz

Ultra-low frequency signal measurements are required in deep space exploration. This paper presents a sampling algorithm to shorten the measurement time of ULF voltage by the time compression method. It is verified that the measurement result of 0.001Hz voltage can be obtained in 550s with an accuracy of 0.01%. The algorithm is also suitable for AC voltage measurements in the range of 1mHz to 1Hz.