CN211905692U - Triangular wave type frequency modulation continuous wave laser radar speed measurement system - Google Patents
Triangular wave type frequency modulation continuous wave laser radar speed measurement system Download PDFInfo
- Publication number
- CN211905692U CN211905692U CN202020121959.1U CN202020121959U CN211905692U CN 211905692 U CN211905692 U CN 211905692U CN 202020121959 U CN202020121959 U CN 202020121959U CN 211905692 U CN211905692 U CN 211905692U
- Authority
- CN
- China
- Prior art keywords
- laser
- optical fiber
- triangular wave
- measurement system
- continuous wave
- 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
Links
Images
Abstract
A frequency modulation continuous wave laser radar speed measurement system in a triangular wave form belongs to the technical field of laser radars. The problem that the laser radar of the traditional pulse system is harmful to people and the problem that frequency modulation nonlinearity is introduced into the frequency modulation continuous wave laser radar are solved. The technical points are as follows: the main laser, the arbitrary waveform generator, the electro-optical modulator and the slave laser form an injection locking system, the main laser emits laser and then enters the electro-optical modulator, the arbitrary waveform generator inhibits carrier modulation on laser carriers through the electro-optical modulator, modulated light is injected into the slave laser through the optical fiber circulator to achieve injection locking, and then the modulated light is divided into probe light and reference light through the coupler. The detection light is emitted to an object through the collimator, the reflected light and the reference light are subjected to coherent detection in the coupler to obtain beat frequency signals, the beat frequency signals are converted into electric signals through the photoelectric detector, and data are acquired and processed through the data acquisition card. The utility model discloses be applied to in the object instantaneous speed measures.
Description
Technical Field
The utility model relates to a frequency modulation continuous wave laser radar system of testing speed, concretely relates to frequency modulation continuous wave laser radar system of testing speed of triangle wave form belongs to laser radar technical field.
Background
Most of traditional laser radars are pulse system radars which have the defects of high peak power, high cost, complex system and the like, and the radar of the pulse system has high transmitting power and can damage the health of people, so that certain limitation exists in use. The radar of the novel system is a frequency modulation continuous wave laser radar, and the system radar mostly adopts a method of directly modulating a laser to realize large sweep frequency bandwidth, so that the measurement precision is improved. However, the method of directly modulating the laser may cause frequency modulation nonlinearity and cause deterioration of measurement accuracy, so that an additional nonlinear algorithm is required to compensate, thereby increasing the complexity of the system, and the method of directly modulating the laser is sensitive to the external environment and is susceptible to interference.
Analysis shows that the traditional laser radar with a pulse system is possibly harmful to people, and the novel frequency modulation continuous wave laser radar introduces frequency modulation nonlinearity, which is a problem to be solved at present, so that the triangular wave type frequency modulation continuous wave laser radar speed measurement system is provided.
SUMMERY OF THE UTILITY MODEL
A brief summary of the present invention is provided below in order to provide a basic understanding of some aspects of the present invention. It should be understood that this summary is not an exhaustive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is discussed later.
In view of this, in order to solve the laser radar of traditional pulse system and to be harmful to the people's problem to and frequency modulation continuous wave laser radar can introduce the nonlinear problem of frequency modulation, and then the utility model designs a frequency modulation continuous wave laser radar speed measuring system of triangle wave form.
The scheme is as follows: the utility model provides a triangular wave type frequency modulation continuous wave laser radar speed measurement system, which comprises a main laser, an arbitrary wave generator, an electro-optical modulator, a slave laser, a first optical fiber circulator, a second optical fiber circulator, a first optical fiber coupler, a second optical fiber coupler, an optical fiber collimator, a photoelectric detector and a data acquisition card;
the waveform output port of the arbitrary waveform generator is connected with the microwave signal input port of the electro-optical modulator, the output port of the main laser is connected with the optical signal input port of the electro-optical modulator, the optical output port of the electro-optical modulator is connected with the I port of the first optical fiber circulator, the output port of the slave laser is connected with the II port of the first optical fiber circulator, the III port of the first optical fiber circulator is connected with the first optical fiber coupler, the light beam is divided into two paths, one path is probe light, the other path is reference light, the probe light enters the optical fiber collimator through the second optical fiber circulator and is sent into the space to detect an object, the light reflected by the moving object is received by the optical fiber collimator, and the received signal and the reference light sequentially enter the second optical fiber coupler, the photoelectric detector and the data acquisition card.
Further: the main laser is a narrow linewidth laser.
Further: the central wavelengths of the master laser and the slave laser are both adjustable near 1550 nm.
Further: the master and slave lasers may be fiber lasers or semiconductor lasers.
Further: the speed measuring system does not contain an optical isolator. So that the system can receive the optical signal reflected by the moving object by using the optical fiber collimator after emitting laser, thereby achieving the function of receiving and transmitting simultaneously.
Further: the arbitrary waveform generator emits a chirp signal in the form of a triangular waveform. The electro-optical modulator is driven to carry out suppressed carrier modulation on a laser carrier, and the modulated laser consists of a positive first-order sideband and a negative first-order sideband.
Further: the modulation signal sent by the arbitrary waveform generator is a triangular wave linear frequency modulation signal with the bandwidth of 1GHz-10GHz and the modulation signal is 3GHz-20 GHz.
Further: the first and second fiber couplers may be 1 x 2 or 2 x 2 ports, the first fiber coupler being 99: 1, the second fiber coupler is a 50: 50 fiber coupler.
Has the advantages that:
the utility model discloses an arbitrary waveform generator and electro-optical modulator modulate laser and can not introduce the frequency modulation nonlinearity. By using the injection locking technology, the transmitted light power is controlled by the slave lasers, the light of the radar speed measuring system is transmitted by the two lasers after injection locking, the transmitted power of the frequency modulation continuous wave radar is small, and the human body cannot be injured. And the triangular wave type frequency modulation continuous wave laser radar speed measurement directly measures the instantaneous speed of the movement of an object, so that the problem of inaccurate indirect speed measurement of a pulse radar is avoided. Additionally, the utility model discloses it is insensitive to external environment, can not receive the environmental disturbance.
Drawings
Fig. 1 is the utility model discloses a radar speed measurement system block diagram.
Fig. 2 is a schematic diagram of the speed measurement of frequency modulated continuous waves.
In fig. 1, the devices are respectively: 1. a main laser; 2. an arbitrary waveform generator; 3. an electro-optic modulator; 4. a slave laser; 5. a first fiber optic circulator; 6. a first fiber coupler; 7. a second fiber optic circulator; 8. a fiber collimator; 9. a second fiber coupler; 10. a photodetector; 11. a data acquisition card; 12. and (5) moving the object.
In FIG. 2, f0The frequency at which the laser emits laser light; f. ofmaxIs the maximum modulation frequency; b is sweep frequency bandwidth; t is a sweep frequency period; f. ofDIs a plurality ofA Doppler frequency shift; τ is the time delay between the reflected light and the reference light; f. of1And f2The beat frequency obtained in the ascending section and the descending section during frequency sweeping respectively.
Detailed Description
Exemplary embodiments of the present invention will be described hereinafter with reference to the accompanying drawings. In the interest of clarity and conciseness, not all features of an actual implementation are described in the specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the device structures and/or processing steps closely related to the solution according to the present invention are shown in the drawings, and other details not relevant to the present invention are omitted.
Example 1: as shown in the figure, the triangular wave type frequency modulation continuous wave laser radar speed measurement system of the embodiment includes a master laser 1, an arbitrary waveform generator 2, an electro-optical modulator 3, a slave laser 4, a first optical fiber circulator 5, a second optical fiber circulator 7, a first optical fiber coupler 6, a second optical fiber coupler 9, an optical fiber collimator 8, a photoelectric detector 10 and a data acquisition card 11;
the main laser 1, the arbitrary waveform generator 2, the electro-optical modulator 3 and the slave laser 4 form an injection locking system, after injection locking, a negative first-order sideband in a modulated signal is inhibited, a side lobe of the positive first-order sideband is also inhibited, and energy is concentrated on the positive first-order sideband.
The frequency of the injection-locked laser light is controlled by the master laser 1, and the output power is controlled by the slave laser 4. As shown in fig. 2, the signal from the arbitrary waveform generator 2 is a chirp continuous signal in the form of a triangular waveform, and the instantaneous speed of the object motion can be calculated from the frequency difference between the probe light and the reference light.
The system uses the optical fiber collimator 8 to emit detection light and receive optical signals reflected by a moving object, thereby achieving the function of receiving and transmitting simultaneously. The moving object 12 may be a moving vehicle.
As shown in the figure, in the working method of the frequency-modulated continuous wave lidar measuring system in the triangular wave form of the embodiment, the main laser 1 emits laser with a narrow line width and a wavelength of 1550nm, and is connected to the electro-optical modulator 3 to perform suppressed carrier modulation, and a modulation signal is from the arbitrary waveform generator 2.
The modulation signal modulates the laser into two sidebands, namely a positive-negative first-order sideband, the modulated laser is sent into the slave laser 4 by using the first optical fiber circulator 5, and the wavelength of the slave laser 4 is finely adjusted to align the wavelength center of the slave laser with the wavelength center of the positive first-order sideband, so that injection locking is realized.
The light from the first optical fiber circulator 5 is divided into two paths by a first optical fiber coupler 6, wherein one path is probe light, and the speed of a moving object is detected; one path is reference light used for coherent detection of the received reflected light.
The detection light enters the optical fiber collimator 8 through the second optical fiber circulator 7 and is sent into the space to detect the object, the light reflected by the moving object is still received by the optical fiber collimator 8, the received signal and the reference light are subjected to coherent detection in the second optical fiber coupler 9, and the electric signal converted by the photoelectric detector 10 is collected by the data acquisition card 11 so as to facilitate subsequent calculation.
Respectively carrying out Fourier transform on the received signal in the ascending frequency band and the descending frequency band of the triangular wave to obtain two beat frequencies f1And f2It is substituted into the velocity equation:
the instantaneous speed of the object motion can be obtained, where λ is the central wavelength of the laser and is 1550 nm.
Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
It is right above the utility model provides a frequency modulation continuous wave laser radar speed measuring system of triangle wave form has carried out detailed introduction. The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.
Claims (7)
1. A triangular wave type frequency modulation continuous wave laser radar speed measurement system is characterized by comprising a main laser (1), an arbitrary waveform generator (2), an electro-optical modulator (3), a slave laser (4), a first optical fiber circulator (5), a first optical fiber coupler (6), a second optical fiber circulator (7), an optical fiber collimator (8), a second optical fiber coupler (9), a photoelectric detector (10) and a data acquisition card (11);
the waveform output port of the arbitrary waveform generator (2) is connected with a microwave signal input port of the electro-optical modulator (3), the output port of the main laser (1) is connected with an optical signal input port of the electro-optical modulator (3), the optical output port of the electro-optical modulator (3) is connected with an I port of the first optical fiber circulator (5), the output port of the slave laser (4) is connected with an II port of the first optical fiber circulator (5), a III port of the first optical fiber circulator (5) is connected with the first optical fiber coupler (6), light beams are divided into two paths, one path is probe light and the other path is reference light, the probe light enters the optical fiber collimator (8) through the second optical fiber circulator (7) and is sent into space to detect an object, light reflected by the moving object (12) is received by the optical fiber collimator (8), and the received signal and the reference light sequentially enter the second optical fiber coupler (9), A photoelectric detector (10) and a data acquisition card (11).
2. A frequency modulated continuous wave lidar velocity measurement system in the form of a triangular wave according to claim 1, characterized in that the primary laser (1) is a narrow linewidth laser.
3. A frequency modulated continuous wave lidar speed measurement system in the form of a triangular wave according to claim 2, characterized in that the master laser (1) and the slave laser (4) are tunable around 1550nm in both central wavelengths.
4. A frequency modulated continuous wave lidar speed measurement system in the form of a triangular wave according to claim 1, characterized in that the master laser (1) and the slave laser (4) may be fiber lasers or semiconductor lasers.
5. A frequency modulated continuous wave lidar speed measurement system according to claim 1, 2, 3 or 4 in the form of a triangular wave, wherein the arbitrary waveform generator (2) emits a chirp signal in the form of a triangular wave.
6. A frequency modulated continuous wave lidar speed measurement system in the form of a triangular wave according to claim 5, wherein the arbitrary waveform generator (2) generates a triangular wave chirp signal in the frequency range of 3GHz-20GHz with a bandwidth of 1GHz-10 GHz.
7. A frequency modulated continuous wave lidar speed measurement system according to claim 5 in the form of a triangular wave, wherein the first fiber coupler (6) and the second fiber coupler (9) may be 1 x 2 or 2 x 2 ports, the first fiber coupler (6) is 99: 1, the second fiber coupler (9) is 50: 50 fiber coupler.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020121959.1U CN211905692U (en) | 2020-01-19 | 2020-01-19 | Triangular wave type frequency modulation continuous wave laser radar speed measurement system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020121959.1U CN211905692U (en) | 2020-01-19 | 2020-01-19 | Triangular wave type frequency modulation continuous wave laser radar speed measurement system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211905692U true CN211905692U (en) | 2020-11-10 |
Family
ID=73303069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020121959.1U Active CN211905692U (en) | 2020-01-19 | 2020-01-19 | Triangular wave type frequency modulation continuous wave laser radar speed measurement system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN211905692U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111175780A (en) * | 2020-01-19 | 2020-05-19 | 哈尔滨理工大学 | Injection locking frequency modulation continuous wave laser radar speed measuring device and method |
-
2020
- 2020-01-19 CN CN202020121959.1U patent/CN211905692U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111175780A (en) * | 2020-01-19 | 2020-05-19 | 哈尔滨理工大学 | Injection locking frequency modulation continuous wave laser radar speed measuring device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111175780A (en) | Injection locking frequency modulation continuous wave laser radar speed measuring device and method | |
| CN100478703C (en) | Chaos laser range-measurement method and device based on semiconductor laser | |
| CN102004255B (en) | Chirp amplitude laser infrared radar distance-Doppler zero-difference detection system | |
| US8119989B2 (en) | Device and method for terahertz imaging with combining terahertz technology and amplitude-division interference technology | |
| US9689772B2 (en) | Optical pulse compression reflectometer | |
| CN106226778A (en) | A kind of coherent lidar system of high resolution measurement remote object | |
| CN110220470B (en) | Single-ended chaotic Brillouin dynamic strain measurement device and method based on Rayleigh scattering | |
| CN102156221B (en) | Photon-integrated-circuit-based instantaneous microwave frequency measurement device and method | |
| CN108344558B (en) | Optical fiber optical time domain reflectometer detection system and method based on linear frequency modulation signal | |
| EP3527964B1 (en) | Light angle modulation measurement apparatus and measurement method | |
| CN109541636B (en) | Non-blind area high-distance resolution laser radar wind measurement system and method | |
| CN101625279B (en) | Device for positioning optical fiber breakpoints and method for confirming breakpoint positions | |
| CN111307054B (en) | High-precision dynamic strain monitoring device and method based on time-delay-free chaotic laser | |
| CN110470376A (en) | A kind of interference distribution type fiber-optic sound sensing device and its method for sensing | |
| CN111999739A (en) | Coherent laser radar method and device for measuring distance and speed by phase modulation | |
| CN112129491A (en) | Optical fiber time delay measuring method and device based on single-optical-frequency comb interference | |
| CN114509097A (en) | Quick Brillouin optical time domain analyzer based on optical frequency comb and frequency agility | |
| CN211905692U (en) | Triangular wave type frequency modulation continuous wave laser radar speed measurement system | |
| CN203642943U (en) | High spatial resolution light frequency domain reflectometer system based on four-wave mixing process | |
| CN114754689A (en) | Phase type distance measuring device and method based on double-electro-optical heterodyne modulation | |
| CN110702985B (en) | Beat frequency type frequency spectrum detecting system | |
| CN106918814A (en) | Ultra wide band scalariform FM/CW laser radar range systems based on double parallel MZM | |
| CN112526538A (en) | Frequency modulation continuous wave laser radar capturing system and method based on FDML | |
| CN109781156B (en) | Brillouin gain spectrum modulation-based BOTDA system and sensing method thereof | |
| CN218120898U (en) | Phase type distance measuring device based on double-electro-optical heterodyne modulation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |