The Development Of A Novel Universal Counter With High Resolution

On the basis of the study on the conventional measurement techniques of frequency and time, this paper presents two novel schemes for frequency and time measurement, and combines these two schemes to realize a universal counter with high resolution and relatively simple structure.For frequency measurement, this paper exploits the variation patterns of phase differences between two periodical signals, and investigates a kind of high resolution measurement scheme for frequency, which is based on the group phase relationship. When there exists a certain relationship between frequencies of two periodical signals, high resolution frequency measurement can be achieved through the accurate detection of group phase coincidence. To realize the high resolution frequency measurement for arbitrary periodical signals with equal-precision, a DDS should be used to synthesize a signal of proper frequency with high stability according to the frequency of signal to be measured. For time interval measurement, this paper illustrates the use of conventional time-voltage conversion method in time interval measurement, and proposes a novel time-voltage conversion method for time interval measurement, which not only lowers the requirement for the hardware structure of time-voltage conversion, but can also obtain very high resolution for time interval measurement by simple calibration procedure.Based on the frequency and time interval measurement techniques presented in this paper, a novel universal counter prototype is developed with initial functions of frequency and time interval measurement, of which frequency measurement resolution can achieve 10-12/s, and time interval measurement resolution can reach 150ps, which can match the measurement precision of Agilent53132.