| 摘要 |
FIELD: measurement equipment.SUBSTANCE: method for measurement of characteristics of resonant structures consists in the fact that a single-frequency sounding oscillation is generated, converted to a multi-frequency one, supplied to the input and received from the output of the resonant structure; frequency of the sounding oscillation is retuned in the measurement range corresponding to the frequency bandwidth of the resonant structure; changes in its parameters, as per which resonant frequency f, amplitude Uand quality factor Q of the resonant structure is determined, are recorded. A peculiar feature of this method is that a sounding oscillation at the input of the resonant structure is shaped as two double-frequency oscillations with two pairs of components of equal or in-pair equal amplitude on frequencies f, fand f, frespectively with similar average frequency f=(f+f)/2=(f+f)/2 and different difference frequencies ?f=f-fand ?f=f-f, which are lower or one of which is equal to a band pass of the resonant structure, average frequency fis retuned. During re-tuning, difference frequencies ?fand ?fremain unchanged, variation in average frequency of sounding oscillation fis recorded, and at the same time, a measurement is made for modulation coefficient mand mof envelopes of beat signal between components of the first and the second double-frequency oscillations at the output of the resonant structure. When modulation coefficient achieves m=m=1, resonant frequency fis measured as equal to the value of average frequency fat this point of time and its corresponding amplitudes of envelopes of beat signal are measured between components of the first and the second double-frequency oscillations Uand Uat the output of the resonant structure; then, resonant amplitude Uof the resonant structure is calculated by the following expression:where ?=U?f/U?f, and quality factor Q of the resonant structure -where i is equal to 1 or 2. To the measurement device of characteristics of resonant structures, which includes the following elements that are in-series connected: a generator that is retunable as to frequency, a converter of a single-frequency oscillation to a multi-frequency one, a commutator and a detector, as well as a controller for control and measurement of characteristics of resonant structures, the first transmission line, a resonant structure and the second transmission line, which are in-series connected to the commutator and where the second output of the commutator is connected to the input of the first transmission line, and the second input of the commutator is connected to the output of the second transmission line, there additionally introduced are retunable selective filters of the first and the second difference frequencies respectively, which are connected with their inputs parallel to the detector output and with the outputs to the first and the second inputs of the controller for control and measurement of characteristics of resonant structures respectively, and the generator retunable as to frequency, the converter of single-frequency oscillation to the multi-frequency one, the commutator, the controller for control and measurement of characteristics of resonant structures and retunable selective filters of the first and the second difference frequencies respectively have control inputs/outputs, which are combined into a control bus.EFFECT: improving sensitivity and accuracy of measurements.2 cl, 3 dwg, 2 app? - r |
