CN-121984510-A - Noise reduction and frequency multiplication sampling circuit and sampling method for phase discrimination sensor

CN121984510ACN 121984510 ACN121984510 ACN 121984510ACN-121984510-A

Abstract

The invention discloses a noise reduction and frequency multiplication sampling circuit and a sampling method for a phase-discrimination sensor, and belongs to the technical field of electronic circuit phase measurement. The noise reduction and frequency multiplication sampling circuit comprises an amplifying circuit, a clamping circuit, a resonant circuit and a comparison circuit which are sequentially connected. The clamping circuit is used for clamping the amplified sinusoidal alternating current signal to be shaped into a trapezoidal signal, the resonant circuit oscillates the trapezoidal signal to generate a high-frequency signal, and the comparison circuit converts the high-frequency signal into a square wave signal. The invention effectively improves the signal frequency under the condition of not changing the original signal frequency from the hardware level, and only needs to carry out high-frequency change on the input signal by adjusting the values of the inductance and the capacitance of the resonant circuit, and the frequency multiplication frequency is not influenced by the operational amplifier, thereby realizing the purpose of high-frequency sampling of the low-frequency signal. The sampling with high resolution can be realized by frequency multiplication and then converting the sampling into square wave signals and collecting data on the rising edge and the falling edge of the square wave signals.

Inventors

PENG KAI
TIAN YUXIN
XU XIAOHU
CAI WEI
Teng Wenhao
CHEN JIAXING

Assignees

重庆理工大学

Dates

Publication Date: 20260505
Application Date: 20260408

Claims (9)

1. The noise reduction and frequency multiplication sampling circuit for the phase discrimination sensor is characterized by comprising an amplifying circuit, a clamping circuit, a resonant circuit and a comparison circuit which are connected in sequence; the amplifying circuit is used for amplifying the sine alternating current signal input by the phase discrimination sensor by a certain multiple; The clamping circuit is used for clamping the amplified sinusoidal alternating current signal so as to shape the sinusoidal alternating current signal into a trapezoidal signal; The resonant circuit is used for self-oscillating the trapezoidal signal, selecting the frequency to be the frequency which becomes larger, and outputting the frequency to be a high-frequency sinusoidal alternating current signal under the action of the frequency selecting characteristic; the comparison circuit is used for converting the high-frequency sinusoidal alternating current signal into a square wave signal; the amplifying circuit, the clamping circuit, the resonant circuit and the comparing circuit work according to a preset time sequence to realize high-speed sampling processing of the phase-discrimination sensor signal.
2. The noise reduction and frequency multiplication sampling circuit for the phase discrimination sensor according to claim 1, wherein the resonance circuit is composed of a capacitor C1 and an inductor L1 which are connected in series, the capacitor C1 is connected with the output of the clamping circuit, the other end of the inductor L1 is grounded, and an output signal at the position where the capacitor C1 is connected with the inductor L1 in series is a frequency multiplication high-frequency sinusoidal alternating current signal.
3. The noise reduction and frequency multiplication sampling circuit for a phase discrimination sensor according to claim 1, wherein the clamping circuit is composed of two diodes in parallel connection, the anode of the first diode D1 is connected with the cathode of the second diode D2 and is connected with the resonant circuit as the output of the clamping circuit, the cathode of the first diode D1 is connected with the anode of the second diode D2 and is grounded, and the anode of the first diode D1 is connected with the output end of the amplifying circuit.
4. The noise reduction and frequency multiplication sampling circuit for a phase discrimination sensor according to claim 3, wherein a resistor R3 is further arranged in the clamping circuit, the anode of the first diode D1 is connected with the output end of the amplifying circuit through the resistor R3, namely one end of the resistor R3 is connected with the output end of the amplifying circuit, and the other end of the resistor R3 is connected with the anode of the first diode D1.
5. The noise reduction and frequency multiplication sampling circuit for a phase detection sensor according to claim 1, wherein the amplifying circuit is an operational amplifier, the input sinusoidal alternating current signal is connected with the non-inverting input end of the operational amplifier, and the amplified sinusoidal alternating current signal is output to the clamping circuit through the output end.
6. The noise reduction and frequency multiplication sampling circuit for a phase discrimination sensor according to claim 5, wherein the inverting input terminal of the operational amplifier is grounded, a resistor R1 is connected between the output terminal and the inverting input terminal of the operational amplifier, and a resistor R2 is connected between the inverting input terminal and the ground of the operational amplifier.
7. The noise reduction and frequency multiplication sampling circuit for a phase discrimination sensor according to claim 1, wherein the main component of the comparison circuit is a comparator, the non-inverting input end of the comparator is connected with the output of the resonant circuit, the square wave signal obtained by conversion is output from the output end of the comparator and is input into the micro control unit, and the inverting input end of the comparator is grounded.
8. A noise reduction and frequency multiplication sampling method for a phase discrimination sensor is characterized by comprising the following steps of, 1) Amplifying an original sinusoidal alternating current signal input by a phase discrimination sensor; 2) Clamping the amplified sinusoidal alternating current signal, and shaping the amplified sinusoidal alternating current signal into a trapezoidal signal; 3) The trapezoidal signal is self-excited by the resonant circuit, frequency-selected to be frequency-increased, and is output as a high-frequency sinusoidal alternating current signal under the action of frequency-selected characteristics; 4) The high-frequency sinusoidal alternating current signal is converted into a square wave signal through a comparison circuit; 5) And data acquisition is carried out on the rising edge and the falling edge of the square wave signal, namely signal sampling is realized.
9. The noise reduction and frequency multiplication sampling method for the phase-discrimination sensor according to claim 8 is characterized in that the noise reduction and frequency multiplication sampling circuit for the phase-discrimination sensor according to any one of claims 1-7 is adopted, and when the sampling is carried out, the square wave signal is output to a micro control unit, and the micro control unit carries out data acquisition on the rising edge and the falling edge of the square wave signal.

Description

Noise reduction and frequency multiplication sampling circuit and sampling method for phase discrimination sensor Technical Field The invention relates to improvement of frequency multiplication circuit technology, in particular to a noise reduction frequency multiplication sampling circuit and a sampling method for a phase discrimination sensor, and belongs to the technical field of electronic circuit phase measurement. Background With the continuous development of electronic technology, the requirement for high-frequency signals in a hardware circuit is continuously improved, and meanwhile, the improvement of the measurement precision of a sensor also has urgent practical requirements. High performance frequency doubling schemes are often required to achieve high frequency doubling and high accuracy sampling of signals. At present, frequency multiplication schemes which are frequently used are operational amplifiers, triodes, step diodes and the like for realizing frequency multiplication on signals. However, the operational amplifier and the triode belong to active devices, and when the frequency doubling circuit is designed, an additional design is required for the working power supply of the operational amplifier or the triode, so that the complexity and the cost of the whole circuit are increased, and the integration and the productization are not facilitated. Secondly, the quality of the multiplied signal obtained by the operational amplifier is related to the magnitude of the frequency and the performance of the amplifier. For the step diode, the principle of the step diode also utilizes the nonlinearity of the diode to realize the function of signal frequency multiplication, but the frequency multiplication circuit has a complex structure, the optimal duty ratio is usually 10% -30%, and the defects of low frequency multiplication efficiency, high cost and the like are overcome. Again, the multiplied signal phase is non-linearly related to the input signal and is difficult to use in a phase coherent system. Disclosure of Invention Aiming at the defects in the prior art, the invention aims to provide the noise-reduction frequency-multiplication sampling circuit for the phase-discrimination sensor, which is all passive devices, has a simple structure, is convenient to adjust and stabilize the signal frequency, can realize high-resolution sampling, reduces out-of-band noise, and is beneficial to improving the measuring precision and real-time performance of the sensor. The technical scheme of the invention is realized as follows: A noise reduction and frequency multiplication sampling circuit for a phase discrimination sensor comprises an amplifying circuit, a clamping circuit, a resonant circuit and a comparison circuit which are connected in sequence; the amplifying circuit is used for amplifying the sine alternating current signal input by the phase discrimination sensor by a certain multiple; The clamping circuit is used for clamping the amplified sinusoidal alternating current signal so as to shape the sinusoidal alternating current signal into a trapezoidal signal; The resonant circuit is used for self-oscillating the trapezoidal signal, selecting the frequency to be the frequency which becomes larger, and outputting the frequency to be a high-frequency sinusoidal alternating current signal under the action of the frequency selecting characteristic; the comparison circuit is used for converting the high-frequency sinusoidal alternating current signal into a square wave signal; the amplifying circuit, the clamping circuit, the resonant circuit and the comparing circuit work according to a preset time sequence to realize high-speed sampling processing of the phase-discrimination sensor signal. Further, the resonant circuit is composed of a capacitor C1 and an inductor L1 which are connected in series, the capacitor C1 is connected with the output of the clamping circuit, the other end of the inductor L1 is grounded, and an output signal at the serial connection position of the capacitor C1 and the inductor L1 is a frequency-doubled high-frequency sinusoidal alternating current signal. Further, the clamping circuit is formed by connecting two diodes in parallel, the anode of the first diode D1 is connected with the cathode of the second diode D2 and is used as the output of the clamping circuit to be connected with the resonance circuit, the cathode of the first diode D1 is connected with the anode of the second diode D2 and is grounded, and the anode of the first diode D1 is connected with the output end of the amplifying circuit. Further, a resistor R3 is further disposed in the clamping circuit, and the anode of the first diode D1 is connected to the output end of the amplifying circuit through the resistor R3, that is, one end of the resistor R3 is connected to the output end of the amplifying circuit, and the other end is connected to the anode of the first diode D1. Further, the main body of t