Research To A Novel Type Of Frequency And Phase Meter

The direct detection for the phase variation of different frequency is unable to realize through traditional methods, especially for the complex frequency signal with phase information continuously change. Based on new theory and new technology, a new phase difference measuring method for arbitrary frequency without frequency conversion is proposed. This paper studies and develops the phase difference measuring method and the corresponding instrument with high resolution and wide frequency range on the premise of low cost.This paper begins with a discussion of the basic phase variation between arbitrary signals followed by edge effect of phase coincidence detection resolution in the application of greatly improve the frequency measurement accuracy and concludes with digital reconstruction technology. O n the basic of the frequency measurement technology with high resolution, no intervals and continuous phase, a virtual signal is reconstructed which has the same frequency valve with the measured nominal frequency. The comparison between the virtual and substances signal and adjustment of virtual signal is helped to achieve a series of precision measurement and subtly adjustment in phase and frequency of arbitrary signals. At last, the system of the frequency and phase meter with wide frequency range is given and the whole working principle and the realization of each function module is presented in details. FPGA is used in the system to realize the core part of measurementthe phase coincidence detection and the module of counting interval doors. While the MCU is used to get the data collected by FPGA to process and show the results to the screen.This study achieves frequency measurement of high resolution continuous ly in a wide frequency range, at the same time the continuous phase characteristics information of the measured signal can be measured directly by the digital processing. The experiments prove that the scheme is correctness and scientific for the stability index achieves 10-12 level and phase resolution reaches Pico level for arbitrary signal frequency and greatly simplifies the structure of measuring equipment. The frequency phase detector designed has the advantages of high resolution, wide frequency range, low additional noise and can measure the phase difference directly. Based on edge effect of phase coincidence detection resolution as well as the digital reconstruction, the conventional phase processing concept that the compared signals must have the same nominal valve is to break through, and the measurement of sophisticated frequency or phase variation can be achieved with high accuracy. The result will be a very significant achievement in a large number of related fields such as PLL technology and quantum frequency standard technology.