CN114859369A - Laser detector sensitivity adjusting device and method - Google Patents

Laser detector sensitivity adjusting device and method Download PDF

Info

Publication number
CN114859369A
CN114859369A CN202210477221.2A CN202210477221A CN114859369A CN 114859369 A CN114859369 A CN 114859369A CN 202210477221 A CN202210477221 A CN 202210477221A CN 114859369 A CN114859369 A CN 114859369A
Authority
CN
China
Prior art keywords
laser
signal
gain
value
guidance device
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.)
Pending
Application number
CN202210477221.2A
Other languages
Chinese (zh)
Inventor
高文元
邬佳杰
俞建杰
刘姝仪
马才伟
梁正
胡传舟
张焱
黄霁月
桑潇蓥
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.)
Huzhou Institute of Zhejiang University
Original Assignee
Huzhou Institute of Zhejiang University
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 Huzhou Institute of Zhejiang University filed Critical Huzhou Institute of Zhejiang University
Priority to CN202210477221.2A priority Critical patent/CN114859369A/en
Publication of CN114859369A publication Critical patent/CN114859369A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/66Tracking systems using electromagnetic waves other than radio waves

Abstract

The invention provides a sensitivity adjusting device and a method for a laser detector, wherein a multidimensional interpretation mechanism is innovatively adopted in a laser receiving and signal processing circuit, the detection sensitivity of the laser receiving circuit is dynamically adjusted according to a plurality of parameters such as the intensity of laser echo energy, the distance information of a facula tracker or a guidance device from a target, the movement speed information of the facula tracker or the guidance device and the like, the detection sensitivity of the laser receiving circuit is ensured to be dynamically and automatically adjusted along with the detected intensity of the echo energy, the adjusted energy range is always kept in a certain reasonable interval, and linear and smooth change is carried out in the interval.

Description

Laser detector sensitivity adjusting device and method
Technical Field
The invention belongs to the field of laser guidance and laser spot tracking, and particularly relates to a sensitivity adjusting device and method for a laser detector.
Background
In the field of laser guidance and laser spot tracking, a spot tracking device or a guidance device needs to track diffuse reflection echo signals returned by laser irradiated on a target from far to near. When the distance from the target is far, the energy of an echo signal is weak, and the laser detection circuit needs to be automatically controlled to have higher detection sensitivity, so that weak signal detection is realized; when the distance to the target is close, the energy of the echo signal is strong, and the detection sensitivity needs to be automatically reduced to avoid the saturation of the detector.
The gain control in the traditional laser detection circuit is in a stepping mode, and the adjustment of the echo energy is discrete, so that the amplitude of the laser echo energy changes nonlinearly, the drastic change of a calculated target azimuth angle is easily caused due to the discrete unsmooth amplitude change during the tracking of laser spots, and serious consequences such as tracking loss can be caused under extreme conditions.
The basis of control and adjustment in the conventional automatic gain control algorithm is only one-dimensional information of the strength of signal echo energy input by a reference receiving front end, and when the basis of gain adjustment is interfered by various complex factors and is not normally changed, an error gain adjustment mode, such as gain imbalance or gain overshoot, is easily generated.
Disclosure of Invention
It is an object of the present invention to provide a laser detector sensitivity adjustment apparatus and method that provides at least the advantages described hereinafter.
The invention also aims to provide a device and a method for adjusting the sensitivity of a laser detector, which innovatively adopt a multi-dimensional interpretation mechanism in a laser receiving and signal processing circuit, dynamically adjust the detection sensitivity of the laser receiving circuit according to a plurality of parameters such as the strength of laser echo energy, the distance information of a facula tracker or a guidance device from a target, the movement speed information of the facula tracker or the guidance device and the like, ensure that the detection sensitivity of the laser receiving circuit is dynamically and automatically adjusted along with the detected strength of the echo energy, and the adjusted energy range is always kept in a certain reasonable interval and is linearly and smoothly changed in the interval.
The technical scheme of the invention is as follows:
laser detector sensitivity adjusting device, it includes:
the laser detection unit is used for acquiring laser echo signals;
a peak hold and threshold comparison unit that divides the laser echo signal into a peak hold signal and a threshold comparison signal after photoelectric conversion and gain amplification processing;
the signal acquisition unit is used for acquiring the peak holding signal, the threshold comparison signal and the movement speed and distance of the current light spot tracker or the guidance device;
the digital potentiometer is electrically connected with the laser detection unit and is used for adjusting the gain voltage value and the detector bias voltage value of the laser detection unit;
the signal processor is electrically connected with the laser detection unit, the signal acquisition unit and the peak value holding and threshold value comparison unit;
wherein;
the signal processor receives a peak value holding signal sent by the signal acquisition unit, the threshold value comparison signal, and the movement speed and distance of the current light spot tracker or the current guidance device;
when the threshold comparison signal reaches a preset amplitude upper limit value, the signal processor calculates the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the guidance device, then calculates the adjustment value of the digital potentiometer and sends the adjustment value to the digital potentiometer, and the digital potentiometer adjusts the gain voltage value and the detector bias voltage value to adjust the sensitivity of the laser detection unit;
the calculation formula is deltaVGC Ks Kv, wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained through ballistic simulation and experiments.
The sensitivity adjusting method of the laser detector comprises the following steps:
presetting a gain voltage value, a detector bias voltage value as maximum values and a preset amplitude upper limit value;
performing photoelectric conversion and gain amplification on the laser echo signal, and dividing the laser echo signal into a peak holding signal and a threshold comparison signal;
acquiring the movement speed and distance of a current light spot tracker or a current guidance device;
when the threshold comparison signal reaches the preset amplitude upper limit value, calculating to obtain the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the current guidance device, further calculating to obtain an adjustment value of a digital potentiometer, and sending the adjustment value to the digital potentiometer, wherein the digital potentiometer adjusts the gain voltage value and the detector bias voltage value, and adjusts the sensitivity of the laser detector;
the calculation formula is deltaVGC (Ks Kd Kv), wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained by ballistic simulation and experiments.
The invention has the following beneficial effects:
according to the intensity of the laser echo received by the detector, the DSP operates a linear smoothing automatic gain control algorithm to control the digital potentiometer to generate an amplifier gain voltage and a detector bias voltage, the laser detection sensitivity is adjusted in a self-adaptive mode, and the purpose of laser spot tracking under complex conditions that the intensity of a weak laser echo signal changes gradually to a strong laser echo signal or the intensity of the echo signal changes randomly is achieved.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
Fig. 1 is a structural block diagram of an embodiment of the sensitivity adjustment apparatus for a laser detector provided in the present invention.
Detailed Description
The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.
It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.
The invention provides a laser detector sensitivity adjusting device, which comprises:
the laser detection unit is used for acquiring laser echo signals;
a peak hold and threshold comparison unit that divides the laser echo signal into a peak hold signal and a threshold comparison signal after photoelectric conversion and gain amplification processing;
the signal acquisition unit is used for acquiring the peak holding signal, the threshold comparison signal and the movement speed and distance of the current light spot tracker or the guidance device;
the digital potentiometer is electrically connected with the laser detection unit and is used for adjusting the gain voltage value and the detector bias voltage value of the laser detection unit;
the signal processor is electrically connected with the laser detection unit, the signal acquisition unit and the peak value holding and threshold value comparison unit;
wherein;
the signal processor receives a peak value holding signal sent by the signal acquisition unit, the threshold value comparison signal, and the movement speed and distance of the current light spot tracker or the current guidance device;
when the threshold comparison signal reaches a preset amplitude upper limit value, the signal processor calculates the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the guidance device, then calculates the adjustment value of the digital potentiometer and sends the adjustment value to the digital potentiometer, and the digital potentiometer adjusts the gain voltage value and the detector bias voltage value to adjust the sensitivity of the laser detection unit;
the calculation formula is deltaVGC (Ks Kd Kv), wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained by ballistic simulation and experiments.
The invention provides a sensitivity adjusting method of a laser detector, which comprises the following steps:
presetting a gain voltage value, a detector bias voltage value as maximum values and a preset amplitude upper limit value;
performing photoelectric conversion and gain amplification on the laser echo signal, and dividing the laser echo signal into a peak holding signal and a threshold comparison signal;
acquiring the movement speed and distance of a current light spot tracker or a current guidance device;
when the threshold comparison signal reaches the preset amplitude upper limit value, calculating to obtain the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the current guidance device, further calculating to obtain an adjustment value of a digital potentiometer, and sending the adjustment value to the digital potentiometer, wherein the digital potentiometer adjusts the gain voltage value and the detector bias voltage value, and adjusts the sensitivity of the laser detector;
the calculation formula is deltaVGC (Ks Kd Kv), wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained by ballistic simulation and experiments.
As shown in fig. 1, the laser detection circuit receives an echo signal returned by the laser irradiator irradiating on a target, and the echo signal is divided into two paths of signals after photoelectric conversion and gain amplification: one path is used for peak value holding, and the other path is used for threshold value comparison to generate a time identification signal. The rising edge of the identification signal at any moment triggers the DSP to generate interruption, the ADC module is used for collecting a laser echo signal kept by a peak value, the change trend and the change range of the next echo energy are predicted according to the amplitude of the echo signal, the distance information of a facula tracker or a guidance device from a target, the movement speed information and the like, the DSP adopts an automatic gain control algorithm to control a digital potentiometer through an SPI (serial peripheral interface) to generate the amplifier gain voltage and the detector bias voltage on a laser detection circuit, and therefore the detection sensitivity of the detector is linearly adjusted along with the echo light intensity.
The automatic gain adjustment algorithm has different algorithms for different application modes: firstly, when a light spot tracker or a guidance device changes from far to near, amplifier gain voltage and detector bias voltage are set to be maximum values, so that the detector has the maximum sensitivity and the maximum detection capability and can detect weak echo signals at a long distance, echo energy signals are enhanced along with the movement of the light spot tracker or the guidance device to a target, and when the amplitude of the echo energy reaches the upper limit of the amplitude set in software, an automatic gain algorithm sets the output voltage of a potentiometer according to the distance from the target at the moment and the relationship between the amplitude of the next echo moment and the magnification of the echo at the moment, so that the gain voltage and the bias voltage of the amplifier are reasonably set, the amplitude is smoothly reduced, and the amplitude is always in a stable amplitude change interval; when the echo energy is not gradually changed from weak to strong but randomly changed, the DSP sets the gain voltage of the amplifier and the bias voltage of the detector to be an intermediate value, when the laser energy is detected to be saturated, the gain is adjusted downwards, when the laser echo signal energy is not detected, the gain is adjusted upwards until the amplitude of the echo energy is located in a reasonable amplitude interval, when the energy is changed, the gain voltage is automatically judged to be adjusted downwards or upwards by combining distance and speed information, the step length of gain adjustment can be determined according to the strength of the echo energy, and the gain voltage can be adjusted quickly or slowly.
Taking the automatic gain control of a laser detection circuit in a certain type of laser guidance project as an example: after the system is powered on, the DSP sets the initial gains of the peripheral and the detection circuit: the detector bias voltage level is set to be the highest level 9 (corresponding to the maximum bias voltage of-180V), the amplifier gain voltage is set to be the highest level 30 (corresponding to the initial gain voltage of the amplifier of 3V), the upper limit of the peak voltage of the detector of automatic gain adjustment is set to be 2200mv, the lower limit of the peak voltage of the detector of automatic gain adjustment is set to be 700mv, the threshold voltage of the comparator is set to be 600mv (signal-to-noise ratio of 3 times), the flying speed of the laser guidance device is 200m/s, and the initial distance of the laser guidance device to the target is 8000 m. When the laser guidance device adopting inertial guidance flies to a target from a long distance and enters a terminal guidance distance of 8000m, the laser detects a weak laser echo signal, an azimuth angle and a pitch angle of the target are calculated according to the echo signal, and the laser guidance device adjusts the posture of the laser guidance device according to angle information so that the target is always positioned at the center of an optical axis of the guidance device. As the distance from the laser guidance device to the target gradually decreases, the energy on the photosensitive surface of the detector gradually increases, when the detected peak voltage exceeds the upper limit of the automatic gain adjustment of 2200mv, the amplifier gain stage is lowered by one step, combining a velocity coefficient kv and a distance coefficient kd, the gain voltage applied to the amplifier is smoothly reduced proportionally, the detected peak voltage decreases smoothly, and as the distance from the target gets closer, when the gain level decreases to 0, the detector bias level is reduced in the same manner until the bias level will also be 0, at which point the detection sensitivity is lowest, when the detection sensitivity is reduced to the minimum, as the laser guidance device is closer to the target, the distance when the peak voltage exceeds the upper limit voltage 2200mv again is the blind distance, i.e. the minimum detection capability of the laser detection device, will no longer give accurate azimuth and elevation information for objects below the blind distance. And when the peak voltage is less than the lower limit of 700mv each time, the bias voltage of the first-stage detector is firstly adjusted back by combining the speed coefficient kv and the distance coefficient kd, and the gain stage of the amplifier is adjusted back after the bias stage is adjusted back to the highest bias stage until the gain stage of the amplifier is adjusted back to the highest gain stage, wherein the minimum value of the peak voltage which can be detected at the moment is the maximum detection capability of the laser detection device.
According to the intensity of the laser echo received by the detector, the DSP operates a linear smooth automatic gain control algorithm to control the digital potentiometer to generate amplifier gain voltage and detector bias voltage, the laser detection sensitivity is adjusted in a self-adaptive mode, and the purpose of laser spot tracking under the complex conditions that a weak laser echo signal changes gradually to a strong laser echo signal or the intensity of the echo signal changes randomly is achieved.
While embodiments of the invention have been disclosed above, it is not intended to be limited to the details shown in the description and the examples, which are set forth, but are fully applicable to various fields of endeavor as are suited to the particular use contemplated, and further modifications will readily occur to those skilled in the art, since the invention is not limited to the details shown and described without departing from the general concept as defined by the appended claims and their equivalents.

Claims (2)

1. Laser detector sensitivity adjusting device, its characterized in that includes:
the laser detection unit is used for acquiring laser echo signals;
a peak hold and threshold comparison unit that divides the laser echo signal into a peak hold signal and a threshold comparison signal after photoelectric conversion and gain amplification processing;
the signal acquisition unit is used for acquiring the peak holding signal, the threshold comparison signal and the movement speed and distance of the current light spot tracker or the guidance device;
the digital potentiometer is electrically connected with the laser detection unit and is used for adjusting the gain voltage value and the detector bias voltage value of the laser detection unit;
the signal processor is electrically connected with the laser detection unit, the signal acquisition unit and the peak value holding and threshold value comparison unit;
wherein;
the signal processor receives a peak value holding signal sent by the signal acquisition unit, the threshold value comparison signal, and the movement speed and distance of the current light spot tracker or the current guidance device;
when the threshold comparison signal reaches a preset amplitude upper limit value, the signal processor calculates the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the guidance device, then calculates the adjustment value of the digital potentiometer and sends the adjustment value to the digital potentiometer, and the digital potentiometer adjusts the gain voltage value and the detector bias voltage value to adjust the sensitivity of the laser detection unit;
the calculation formula is deltaVGC (Ks Kd Kv), wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained by ballistic simulation and experiments.
2. The sensitivity adjusting method of the laser detector is characterized by comprising the following steps of:
presetting a gain voltage value, a detector bias voltage value as maximum values and a preset amplitude upper limit value;
performing photoelectric conversion and gain amplification on the laser echo signal, and dividing the laser echo signal into a peak holding signal and a threshold comparison signal;
acquiring the movement speed and distance of a current light spot tracker or a current guidance device;
when the threshold comparison signal reaches the preset amplitude upper limit value, calculating to obtain the change trend and the change range of the next laser echo signal by adopting an automatic gain algorithm according to the movement speed and the distance of the current spot tracker or the current guidance device, further calculating to obtain an adjustment value of a digital potentiometer, and sending the adjustment value to the digital potentiometer, wherein the digital potentiometer adjusts the gain voltage value and the detector bias voltage value, and adjusts the sensitivity of the laser detector;
the calculation formula is deltaVGC (Ks Kd Kv), wherein deltaVGC represents the gain voltage variation of the digital potentiometer, Ks represents the gain voltage variation coefficient caused by the flying speed of the laser guidance device, Kd represents the distance gain voltage conversion relation coefficient between the laser guidance device and the target, Kv represents the gain voltage variation relation caused by the variation of the unit digital potentiometer, and the coefficients can be obtained by ballistic simulation and experiments.
CN202210477221.2A 2022-05-03 2022-05-03 Laser detector sensitivity adjusting device and method Pending CN114859369A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210477221.2A CN114859369A (en) 2022-05-03 2022-05-03 Laser detector sensitivity adjusting device and method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210477221.2A CN114859369A (en) 2022-05-03 2022-05-03 Laser detector sensitivity adjusting device and method

Publications (1)

Publication Number Publication Date
CN114859369A true CN114859369A (en) 2022-08-05

Family

ID=82634895

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210477221.2A Pending CN114859369A (en) 2022-05-03 2022-05-03 Laser detector sensitivity adjusting device and method

Country Status (1)

Country Link
CN (1) CN114859369A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115656974A (en) * 2022-12-09 2023-01-31 武汉灵途传感科技有限公司 Detection method for laser radar integrated double APDs

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115656974A (en) * 2022-12-09 2023-01-31 武汉灵途传感科技有限公司 Detection method for laser radar integrated double APDs

Similar Documents

Publication Publication Date Title
CN110308456B (en) Bias voltage adjusting device for improving detection distance and laser radar system
CN111198360B (en) Laser radar and control method thereof
US5097458A (en) Servo control system for optical disk device
US5416759A (en) Variable gain digital servo system with improved resolution and reduced quantization error
WO2020103805A1 (en) Lidar signal receiving circuits, lidar signal gain control methods, and lidars using the same
CN109870678B (en) Laser radar transmitting power and echo gain automatic adjusting method and adjusting device
CN114859369A (en) Laser detector sensitivity adjusting device and method
US5653902A (en) Method and device of correcting a welding path of an automatic welding apparatus
DE3833330C2 (en) Device for detecting a light beam from an optical memory
DE102005046989A1 (en) Vehicle laser radar sensor, has zero-cross comparator to compare light reception signals outputted from photoreceptive units with preset signal to output comparison signal, and integrator to integrate one-bit digital data for each unit
EP2917757B1 (en) Optoelectronic detection device with adjustable bias voltage of an avalanche-photodetector for a motor vehicle, motor vehicle and corresponding method
CN104393852A (en) Target signal automatic gain adjusting system and method
CN109946674A (en) Full wave shape laser radar apparatus
CN108020121B (en) A kind of laser seeker energy management system and method
CN112162258B (en) Portable multi-elevation detection radar optical device and self-adaptive scanning method thereof
CN101882918A (en) Automatic gain control method and device
JPH08201519A (en) Light reception circuit
JP3999055B2 (en) Signal detection processing circuit
CN112198520B (en) Method for reducing range finding blind area of infrared photoelectric sensor
CN113267825A (en) Dual-channel background suppression photoelectric sensor integrated circuit and control method
KR100230249B1 (en) Optimization method and device of track servo gain of optical disc system
US20040052197A1 (en) Disk device
JPH05129857A (en) Gain control method for avalanche photodiode
CN106526599A (en) Ultrasonic ranging system, echo signal receiving method and device
WO1992004628A1 (en) Ultrasonic microscope

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