Complicated Frequency Measurement System Dsign For Super High Resolution

In the field of modern electronic technology, quantum frequency standard, communication technology, high frequency control device, basic scientific research and scientific instruments, there are a large number of complex frequency signals. The precision measurement and control for these signals have great scientific significance, so the time and frequency measurement and control technology occupies an extremely important position. Traditional technology is generally through frequency conversion making reference signal frequency equal to the frequency of the measured signal, or using the related high-precision time interval measurement methods, such as analog interpolation, cursor, time-digital conversion auxiliary measuring. To implement circuit is complex, and the final measurement precision is still limited. The highest accuracy now may be within 10-11/s level. Therefore, in view of the high resolution of complex frequency signal effective measurement can improve accuracy, function expansion in the field of multiple aspects to have the significant effect.Aiming at the problems existing in various frequency measurement methods as quantization error and the measurement accuracy is not high, this paper puts forward a new method of frequency measurement with technology based on phase coincidence detection and edge detection, and its extension application can be used for the determination of related parameters of time and frequency signals. In this paper, the principle of phase coincidence detection has carried on the detailed elaboration, based on the group phase synchronization. As the coincidence point fuzzy zone different, the delay time of phase coincidence detection circuit is different, thus makes the two lines of fuzzy area edge detection information of the same position inverse, after "XOR" processing to obtain the fuzzy region edge accurately. On the basis of this formation the measurement gate ensure the synchronization between the signal phase groups, maximally eliminate the quantization error, and through the stability of the measurement device resolution greatly improve the accuracy of measurement. This measurement is always kept the original information of signal, therefore has the ability of phase processing, and also can measure other physical quantities of the measured complex frequency signals, the precision of frequency measurement from 10-12 / s to 10-17/days. In this paper, using the edge effect realize frequency measurement method when measured signal and the reference signal in the complex relationship. This method does not need a complex frequency conversion, there is no special auxiliary precision time measuring way, at the same time, it can get high measurement resolution based on phase treatment.This paper detailed introduces the working principle of the overall system design, including the hardware implementation method. The signal conditioning, amplifying and shaping circuit are using ECL circuit with CPLD phase coincidence detection design completed, and the data acquisition, processing, counting and displaying is realized in virtual instrument LabVIEW software.Experiments show that, by coincidence detection generated gate with the edge effect, makes the measurement accuracy depends on the stability of a circuit rather than only resolution. Measurement accuracy can be improved 2 to 3 orders of magnitude. This method has the advantages of novel principle, high measuring accuracy, simple equipment, easy to implement, small volume, high reliability, etc.