CN108347231B - Broadband 90-degree phase shifter - Google Patents

Broadband 90-degree phase shifter Download PDF

Info

Publication number
CN108347231B
CN108347231B CN201810085250.8A CN201810085250A CN108347231B CN 108347231 B CN108347231 B CN 108347231B CN 201810085250 A CN201810085250 A CN 201810085250A CN 108347231 B CN108347231 B CN 108347231B
Authority
CN
China
Prior art keywords
current
resistor
output
operational amplifier
phase difference
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810085250.8A
Other languages
Chinese (zh)
Other versions
CN108347231A (en
Inventor
谭超
王家成
李宗燎
杨哲
龚晓辉
乐周美
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Three Gorges University CTGU
Original Assignee
China Three Gorges University CTGU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Three Gorges University CTGU filed Critical China Three Gorges University CTGU
Priority to CN202110524143.2A priority Critical patent/CN113328727B/en
Priority to CN201810085250.8A priority patent/CN108347231B/en
Publication of CN108347231A publication Critical patent/CN108347231A/en
Application granted granted Critical
Publication of CN108347231B publication Critical patent/CN108347231B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03HIMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00Networks using active elements
    • H03H11/02Multiple-port networks
    • H03H11/16Networks for phase shifting
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02DCLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00Reducing energy consumption in communication networks
    • Y02D30/70Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Networks Using Active Elements (AREA)
  • Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)

Abstract

A broadband 90 DEG phase shifter comprises a resistor R5, a resistor R3, a capacitor C2, an operational amplifier A1, a current controllable resistance unit and a phase difference/current conversion unit. The resistor R5, the resistor R3, the capacitor C2, the operational amplifier A1 and the current controllable resistance unit form a phase-shifting circuit. The phase difference/current conversion unit receives an input signal Uin and an output signal Uo of the operational amplifier A1, and converts the phase difference of two paths of signals into current output. The current controllable resistance unit receives the output current of the phase difference/current conversion unit, converts the current change into resistance change, controls the phase of the output signal of the phase shift circuit, and ensures that the phase difference between the input signal and the output signal of the phase shift circuit is 90 degrees. The phase shifter can adaptively track frequency change to input sinusoidal signals with frequency change in a wider frequency range to realize 90-degree phase shift under different frequencies.

Description

Broadband 90-degree phase shifter
Technical Field
The invention relates to a broadband 90-degree phase shifter which is used for accurately shifting 90-degree phase of an alternating current sinusoidal signal.
Background
An optical pump magnetometer is a weak magnetic measuring instrument, which takes the Zeeman effect of some gaseous alkali metal atoms (39K, 87Rb, 133Cs, etc.) or some inert gas (3He, 4He) atoms in an external magnetic field as the basis, under the combined action of optical pumping and a radio frequency magnetic field, the atoms generate an optical magnetic resonance phenomenon, the size of the external magnetic field can be determined according to the frequency of the radio frequency magnetic field, and the optical pump magnetometer can be divided into a tracking type and a self-excited oscillation type according to different working modes. The two structures of magnetometers need to shift the phase of an output signal by 90 degrees and then feed back the phase to the sensor absorption chamber, so that the intensity of light is modulated by working substances in the absorption chamber in an absorption mode, the intensity change frequency of the modulated light is detected by the photosensitive diode, and the frequency is in direct proportion to an external magnetic field, and then a magnetic field value to be measured can be obtained. The phase shift error can cause the magnetic field measurement error, so the design of the high-precision broadband 90-degree phase shift network is one of the key technologies of the optical pump magnetometer.
A cesium optical pump magnetometer for measuring the geomagnetic field needs an accurate 90-degree phase shift circuit capable of self-adapting to frequency change in the range of 50KHz-350KHz, namely, when the input frequency of the circuit is required to be randomly changed in the range of 50KHz-350KHz, the phase difference of the output signal of the cesium optical pump magnetometer is always lagged behind the phase difference of the input signal by 90 degrees. Most of the current phase shifting circuits shift the phase of a signal with a narrow frequency range or a fixed frequency. For example, the' 201410411245.3 patent describes a phase shift circuit using the integration and comparator principle, which cannot perform a precise 90 ° phase shift on signals with frequencies higher than 10KHz due to the time required for the charging and discharging process of the integration. In addition, a phase shift circuit realized by using an RLC network is provided, and the phase shift network can accurately perform 90-degree phase shift on a fixed frequency point by adjusting R, L, C three parameters, and once the frequency changes, the phase shift angle deviates from 90 degrees, so that the 90-degree phase shift of self-adaptive frequency change in a broadband range cannot be realized. In addition, 90 ° phase shifters in a wide frequency band are also required in other engineering applications.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a broadband 90-degree phase shifter which can adaptively track frequency change to sinusoidal signals with changed input frequency and realize 90-degree phase shift under different frequencies in a wider frequency range.
The technical scheme adopted by the invention is as follows:
a broadband 90 DEG phase shifter comprises a resistor R5, a resistor R3, a capacitor C2, an operational amplifier A1, a current controllable resistance unit and a phase difference/current conversion unit.
One end of the resistor R5 is connected with the phase difference/current conversion unit, the other end of the resistor R5 is connected with one end of a resistor R3 and the reverse input end of an operational amplifier A1, and the other end of the resistor R3 is connected with the output end of an operational amplifier A1;
one end of the capacitor C2 is connected with one end of the resistor R5, and the other end of the capacitor C2 is connected with the current controllable resistance unit and the equidirectional input end of the operational amplifier A1;
the output end of the operational amplifier A1 is connected with the phase difference/current conversion unit, and the phase difference/current conversion unit is connected with the current controllable resistance unit;
the resistor R5, the resistor R3, the capacitor C2, the operational amplifier A1 and the current controllable resistance unit form a phase-shifting circuit;
the phase difference/current conversion unit receives an input signal Uin and an output signal Uo of an operational amplifier A1, and converts the phase difference of two paths of signals into current output;
the current controllable resistance unit receives the output current of the phase difference/current conversion unit, converts the current change into resistance change, controls the phase of the output signal of the phase shift circuit, and ensures that the phase difference between the input signal and the output signal of the phase shift circuit is 90 degrees.
The current controllable resistance unit comprises a photoresistor R and a light emitting diode D1, wherein the light emitting diode D1 is bonded with a transparent window of the photoresistor R and is packaged by a heat shrinkable tube to form a 4-port element;
wherein, the port I and the port II are respectively: an anode of the light emitting diode D1, a cathode of the light emitting diode D1;
a port I is connected with a current output end Iout of the phase difference/current conversion unit;
the port is grounded;
the port (c) and the port (c) are output pins of the photoresistor R, wherein the port (c) is connected with the homodromous input end of the operational amplifier A1, and the port (c) is grounded.
The phase difference/current conversion unit includes:
the first comparator consists of a resistor R1, a resistor R4 and a comparator A2;
the second comparator is composed of a resistor R9, a resistor R6 and a comparator A3;
the output end of the first path of comparator is connected with two input ends of a two-input AND gate U1A;
the output ends of the first path of comparator and the second path of comparator are respectively connected with two input ends of a two-input AND gate U1B;
the resistor R2 is connected with the capacitor C1 to form a low-pass filter of the first and gate output;
the resistor R10 is connected with the capacitor C3 to form a low-pass filter of the output of the second AND gate;
two paths of output signals after low-pass filtering are respectively connected into two paths of voltage followers formed by an operational amplifier A4 and an operational amplifier A5: the first path of voltage follower and the second path of voltage follower are connected;
the output voltage of the first path of voltage follower passes through a voltage division network formed by resistors R8 and R7 and then is connected to an operational amplifier A6 together with the output voltage of the second path of voltage follower;
the output end of the operational amplifier A6 is connected with a current amplification circuit which is composed of a resistor R11, a resistor R13 and a PNP triode Q1, and Iout of the current amplification circuit is connected with a port (R) of the current controllable resistance unit.
Compared with the existing 90-degree phase shifter or phase shift circuit, the broadband 90-degree phase shifter has the following technical effects: 1. the phase shift precision is high: the phase shift precision of the circuit is determined by whether the voltage difference of the positive input end and the negative input end of the amplifier is zero, if the voltage difference is zero, the phase difference is 90 degrees, the positive input end and the negative input end of the circuit are required to be consistent according to the virtual break principle of the operational amplifier, otherwise, the output of larger voltage is generated under the condition of extremely large gain, so that the phase shift circuit is controlled to carry out phase adjustment, the input voltage difference of the amplifier can be adjusted according to the phase adjustment result, and finally, the input voltage difference is zero, so that the phase shift precision.
2. The phase shift range is wide: under the condition of the selected capacitance, the 90-degree accurate phase shift can be realized on the input sinusoidal signal with any frequency within the working limit range of the selected electronic component.
3. The response tracking speed is high: once the frequency of the input sinusoidal signal changes, the phase difference between the input signal and the output signal deviates from 90 degrees, and because the operational amplifier works in an open loop state and the open loop gain is extremely large, the control speed of the phase difference adjustment is very high, and the phase difference can quickly return to 90 degrees.
Drawings
Fig. 1 is a block diagram of a wideband 90 ° phase shifter according to the present invention.
Fig. 2 is a schematic diagram of the current controllable resistance unit according to the present invention.
Fig. 3 is a circuit diagram of the phase difference/current conversion unit according to the present invention.
Detailed Description
As shown in fig. 1, in order to achieve the above object, the present invention adopts the following technical solutions: a wide-band 90 DEG phase shifter includes resistors R5, R3, a capacitor C2, an operational amplifier A1, a current controllable resistance unit and a phase difference/current conversion unit. The resistors R5 and R3, the capacitor C2, the operational amplifier a1, and the current controllable resistance unit constitute a phase shift circuit, and the phase difference between the input signal and the output signal of the phase shift circuit is controlled by the output current of the phase difference/current conversion unit.
The resistors R5 and R3, the capacitor C2, the operational amplifier A1 and the current controllable resistance unit form a phase-shifting network, according to the virtual short and virtual break principle of the operational amplifier, R5 is taken as R3, and the phase-shifting network needs to meet the following conditions for realizing 90-degree phase shifting:
Figure GDA0002982510530000031
in the formula: f is the frequency of the input sinusoidal signal, and R is the resistance value of the current controllable resistance unit. Once capacitance C2After selection, R must be adjusted according to different input frequencies to maintain the input signal 90 ° out of phase with the output signal for different input frequencies f.
The current controllable resistance unit is composed of a photoresistor R and a light-emitting diode D1, the light-emitting diode and a transparent window of the photoresistor are bonded together and packaged by a heat-shrinkable tube to form a 4-port element, wherein ports (i) and (ii) are an anode and a cathode of the light-emitting diode, the port (i) is connected with a current output Iout of the phase difference/current conversion unit, and the port (ii) is grounded; ports (c) and (c) are photoresistor output pins, wherein the port (c) is connected with the negative input end of the amplifier A1, and the port (c) is grounded. Because the whole device is in a sealed state, the photoresistor is not illuminated, and the ports (c) and (d) have extremely large output resistors. After the current is injected into the port I and the port II is grounded, the light emitting diode emits light to irradiate the photoresistor, so that the resistance value of the photoresistor changes along with the change of the luminous intensity of the light emitting diode, the luminous intensity of the light emitting diode can be changed by changing the current of the injection port I, and the purpose of changing the output resistors of the port III and the port IV is achieved.
The phase difference/current conversion unit includes: the resistors R1 and R4 and the comparator A2 form a first comparator, and the resistors R9 and R6 and the comparator A3 form a second comparator; the output of the first path of comparator is connected with two input ends of a two-input AND gate U1A, and the outputs of the first path of comparator and the second path of comparator are respectively connected with two input ends of a two-input AND gate U1B; the resistor R2 and the capacitor C1 form a low-pass filter of the output of the first AND gate, and the resistor R10 and the capacitor C3 form a low-pass filter of the output of the second AND gate; the two paths of output signals after low-pass filtering are respectively connected into two paths of voltage followers formed by operational amplifiers A4 and A5; the output voltage of the first follower passes through a voltage division network formed by resistors R8 and R7 and then is connected into an operational amplifier A6 together with the output voltage of the second follower; the output of the operational amplifier A6 is connected with a current amplifying circuit composed of resistors R11 and R13 and a PNP triode Q1, and the Iout of the current amplifying circuit is connected with the port (R) of the current controllable resistance unit.
Resistors R1 and R4 and a comparator A2 form a first comparator, the first comparator changes an input sine signal Uin into a TTL square wave signal with a duty ratio of 50%, the output square wave signal is respectively connected to pins 1 and 2 of a two-input AND gate U1A and pin 4 of the two-input AND gate U1B, and the waveform of an output pin 3 of the U1A is completely consistent with the waveform of input pins 1 and 2 and is a square wave with a duty ratio of 50%. After the square wave with 50% duty ratio output by the pin 3 of the U1A is low-pass filtered by R1 and C1, a dc voltage of VCC/2 is generated at the pin 3 of the positive input terminal of the amplifier a4, and when the dc voltage is taken as R8 ═ R7, the dc voltage passes through a voltage follower formed by an amplifier a4 and a voltage division network formed by R8 and R7, and then a dc voltage of VCC/4 is generated at the pin 3 of the negative input terminal of the amplifier a 6.
Resistors R9 and R6 and a comparator A3 form a second comparator which converts a sinusoidal signal Uo output by the phase-shift circuit into a TTL square waveThe outgoing square wave signal is connected into the 5 pins of the two-input AND gate U1B, and the phase difference between Uin and Uo is assumed to be
Figure GDA0002982510530000041
Then a duty cycle of "d" is generated at output pin 6 of U1B
Figure GDA0002982510530000042
The square wave of (2). 6 pin output duty cycle of U1B
Figure GDA0002982510530000043
After being low-pass filtered by R10 and C3, the square wave of the amplifier A5 is generated at the positive input end 3 pins
Figure GDA0002982510530000044
The dc voltage is inputted to the positive input terminal of the amplifier a6 after passing through a voltage follower constituted by the amplifier a 5.
The amplifier A6 is used as an error amplifier for combining the DC voltage VCC/4 output from the first path with the DC voltage output from the second path
Figure GDA0002982510530000051
The amplified voltage signal acts on a current amplifier formed by R11 and Q1, and a current signal is output and injected into the port (R) of the current controllable resistor to control the resistance value between the port (R) and the port (R) of the current controllable resistor. Because the amplifier A6 is in open-loop working state, if and only if the DC voltage VCC/4 outputted by the first path and the DC voltage outputted by the second path are
Figure GDA0002982510530000052
When they are equal, the output voltage of the amplifier A6 no longer changes, and the calculation can be made
Figure GDA0002982510530000053
I.e. Uin and Uo are 90 out of phase.
When the frequency of the input signal Uin changes, the phase difference between the input signal Uin and the output signal Uo of the phase shift circuit is not 90Then the DC voltage VCC/4 output by the first path and the DC voltage output by the second path of the amplifier A6 are set
Figure GDA0002982510530000054
When the voltage drop of the output of the amplifier A6 is not equal to that of the current amplifier composed of R11 and Q1, the current is generated to adjust the output resistance of the current controllable resistor, so as to change the phase difference between Uin and Uo until the phase difference is 90 degrees, namely, the DC voltage VCC/4 output by the first path of the amplifier A6 and the DC voltage VCC/4 output by the second path of the amplifier A6 are equal to each other
Figure GDA0002982510530000055
Until equal.
As the cesium optical pump magnetometer for measuring the geomagnetic field needs to shift the phase of an output signal by 90 degrees within the range of 50KHz to 350KHz and feed back the phase to a sensor, a self-oscillation system is formed, and the oscillation output frequency is in direct proportion to an external magnetic field. The broadband 90-degree phase shifter can be used for a broadband phase shifting network of a cesium optical pump magnetometer.

Claims (2)

1. A broadband 90 DEG phase shifter comprises a resistor R5, a resistor R3, a capacitor C2, an operational amplifier A1, a current controllable resistance unit and a phase difference/current conversion unit; the method is characterized in that:
one end of the resistor R5 is connected with the phase difference/current conversion unit, the other end of the resistor R5 is connected with one end of a resistor R3 and the reverse input end of an operational amplifier A1, and the other end of the resistor R3 is connected with the output end of an operational amplifier A1;
one end of the capacitor C2 is connected with one end of the resistor R5, and the other end of the capacitor C2 is connected with the current controllable resistance unit and the equidirectional input end of the operational amplifier A1;
the output end of the operational amplifier A1 is connected with the phase difference/current conversion unit, and the phase difference/current conversion unit is connected with the current controllable resistance unit;
the resistor R5, the resistor R3, the capacitor C2, the operational amplifier A1 and the current controllable resistance unit form a phase-shifting circuit;
the phase difference/current conversion unit receives an input signal Uin and an output signal Uo of an operational amplifier A1, and converts the phase difference of two paths of signals into current output;
the current controllable resistance unit receives the output current of the phase difference/current conversion unit, converts the current change into resistance change, controls the phase of the output signal of the phase shift circuit and ensures that the phase difference between the input signal and the output signal of the phase shift circuit is 90 degrees;
the phase difference/current conversion unit includes:
the first comparator consists of a resistor R1, a resistor R4 and an operational amplifier A2;
the second path of comparator consists of a resistor R9, a resistor R6 and an operational amplifier A3;
the output end of the first path of comparator is connected with two input ends of a two-input AND gate U1A;
the output ends of the first path of comparator and the second path of comparator are respectively connected with two input ends of a two-input AND gate U1B;
the resistor R2 is connected with the capacitor C1 to form a low-pass filter of the first and gate output;
the resistor R10 is connected with the capacitor C3 to form a low-pass filter of the output of the second AND gate;
two paths of output signals after low-pass filtering are respectively connected into two paths of voltage followers formed by an operational amplifier A4 and an operational amplifier A5: the first path of voltage follower and the second path of voltage follower are connected;
the output voltage of the first path of voltage follower passes through a voltage division network formed by resistors R8 and R7 and then is connected to an operational amplifier A6 together with the output voltage of the second path of voltage follower;
the output end of the operational amplifier A6 is connected with a current amplification circuit which is composed of a resistor R11, a resistor R13 and a PNP triode Q1, and Iout of the current amplification circuit is connected with a port (R) of the current controllable resistance unit.
2. A wideband 90 ° phase shifter according to claim 1, wherein: the current controllable resistance unit comprises a photoresistor R and a light emitting diode D1, wherein the light emitting diode D1 is bonded with a transparent window of the photoresistor R and is packaged by a heat shrinkable tube to form a 4-port element;
wherein, the port I and the port II are respectively: an anode of the light emitting diode D1, a cathode of the light emitting diode D1;
a port I is connected with a current output end Iout of the phase difference/current conversion unit;
the port is grounded;
the port (c) and the port (c) are output pins of the photoresistor R, wherein the port (c) is connected with the homodromous input end of the operational amplifier A1, and the port (c) is grounded.
CN201810085250.8A 2018-01-29 2018-01-29 Broadband 90-degree phase shifter Active CN108347231B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202110524143.2A CN113328727B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifting method
CN201810085250.8A CN108347231B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810085250.8A CN108347231B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifter

Related Child Applications (1)

Application Number Title Priority Date Filing Date
CN202110524143.2A Division CN113328727B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifting method

Publications (2)

Publication Number Publication Date
CN108347231A CN108347231A (en) 2018-07-31
CN108347231B true CN108347231B (en) 2021-06-18

Family

ID=62961699

Family Applications (2)

Application Number Title Priority Date Filing Date
CN202110524143.2A Active CN113328727B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifting method
CN201810085250.8A Active CN108347231B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifter

Family Applications Before (1)

Application Number Title Priority Date Filing Date
CN202110524143.2A Active CN113328727B (en) 2018-01-29 2018-01-29 Broadband 90-degree phase shifting method

Country Status (1)

Country Link
CN (2) CN113328727B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111896784B (en) * 2020-08-31 2024-09-27 连云港杰瑞电子有限公司 Square wave generating device and method for detecting digital-axial angle converter

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06296135A (en) * 1993-04-09 1994-10-21 Fujitsu Ltd Phase locked loop circuit
CN1117231A (en) * 1993-10-05 1996-02-21 Eta草图制造公司 Phase difference and amplitude correction circuit
US7705667B2 (en) * 2007-10-10 2010-04-27 Kabushiki Kaisha Toshiba Filter adjusting circuit
CN101958712A (en) * 2010-11-10 2011-01-26 南京大学 Analog phase-locked loop circuit without phase difference
CN202018965U (en) * 2011-02-26 2011-10-26 任永斌 Coupler with light-emitting diode (LED) and photoresistor

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4040788A1 (en) * 1990-12-15 1992-06-17 Univ Chemnitz Tech Phase-responsive rectifier circuit for AM carrier signal - with sampling of original signal and phase-shifted signal to provide stepped DC output voltage
JP2005328272A (en) * 2004-05-13 2005-11-24 Nec Electronics Corp Pll circuit and frequency setting circuit using the same
CN201590774U (en) * 2009-12-10 2010-09-22 厦门科华恒盛股份有限公司 Autobalance control device for output of inverter
CN104506072B (en) * 2014-11-20 2017-11-21 许继电气股份有限公司 A kind of phase-shifting full-bridge peak current control circuitry based on PWM controller

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06296135A (en) * 1993-04-09 1994-10-21 Fujitsu Ltd Phase locked loop circuit
CN1117231A (en) * 1993-10-05 1996-02-21 Eta草图制造公司 Phase difference and amplitude correction circuit
US7705667B2 (en) * 2007-10-10 2010-04-27 Kabushiki Kaisha Toshiba Filter adjusting circuit
CN101958712A (en) * 2010-11-10 2011-01-26 南京大学 Analog phase-locked loop circuit without phase difference
CN202018965U (en) * 2011-02-26 2011-10-26 任永斌 Coupler with light-emitting diode (LED) and photoresistor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
移相电路原理;逍遥1210man;《百度文库》;20140623;全文,附图3 *

Also Published As

Publication number Publication date
CN113328727B (en) 2024-07-09
CN108347231A (en) 2018-07-31
CN113328727A (en) 2021-08-31

Similar Documents

Publication Publication Date Title
CN104734656A (en) Radio frequency signal source with amplitude modulation and automatic level control functions
CN103579896B (en) The laser frequency stabilizing system of Pound-Drever-Hall without phase shifter
CN101777891A (en) Ultrafast edge step pulse generating method and generator thereof
CN204044355U (en) A kind of calibrating installation of laser ranging and surveying instrument
Jeon et al. Simple-structured, subfemtosecond-resolution optical-microwave phase detector
CN108347231B (en) Broadband 90-degree phase shifter
CN104730310A (en) Measuring device with variable attenuation unit
CN107645341B (en) Microwave photon phase discrimination method and device and microwave photon phase locking method and device
CN102768554A (en) Constant-current source for gyroscope gauge outfit torquer
CN104076859A (en) Microwave temperature compensation detector
CN105548710A (en) Enhanced automatic balance bridge and method for realizing impedance measurement
CN108444463A (en) A kind of digital closed-loop optic fiber gyroscope circuit inhibiting spike asymmetry
SU572667A1 (en) Piezoelectric measuring transducer
CN107747952B (en) A kind of optical fibre gyro closed loop feedback control triangular phase modulating wave driving device
JPH026758A (en) Voltage/frequency converter and use thereof for light waveguide transmission system
CN204168278U (en) A kind of orthogonal lock-in-amplifier system for CPT atomic clock
FI87868C (en) Loop filter for a frequency synthesizer
US10845394B2 (en) Null detector devices and systems employing same
US9400179B2 (en) Propagation velocity compensated position measurement sensor
CN104296740A (en) Fiber-optic gyroscope main control panel crystal oscillator selecting method based on anti-fuse FPGA
CN209373109U (en) A kind of phase distancemeter
CN203536724U (en) Laser frequency stabilization device realizing third-order differential signal feedback
CN201886055U (en) Full-range high-linearity analog signal buffer circuit
RU2000023C1 (en) Optical contactless level gauge
CN111044943B (en) Multi-spectrum closed-loop locking method and system for CPT magnetometer

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant