CN109283518B - Distance measuring system - Google Patents
Distance measuring system Download PDFInfo
- Publication number
- CN109283518B CN109283518B CN201811271538.0A CN201811271538A CN109283518B CN 109283518 B CN109283518 B CN 109283518B CN 201811271538 A CN201811271538 A CN 201811271538A CN 109283518 B CN109283518 B CN 109283518B
- Authority
- CN
- China
- Prior art keywords
- signal
- module
- signals
- transmitting
- radiation group
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO 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
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/08—Systems for measuring distance only
- G01S13/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO 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
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/024—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using polarisation effects
- G01S7/026—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using polarisation effects involving the transmission of elliptically or circularly polarised waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO 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
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/35—Details of non-pulse systems
Abstract
The invention relates to the field of distance measurement and discloses a distance measurement system, which comprises: the signal generation module, the low-pass filtering module, the power distribution module, the power amplification module, the antenna module, the low-noise amplification module, the signal amplification module, the mixing module, the intermediate frequency filtering module and the signal conversion module.
Description
Technical Field
The invention relates to the field of distance measurement, in particular to a distance measurement system.
Background
In the prior art, ranging applications are very mature, including short-range ranging and long-range ranging, for example: long range radar ranging, short range millimeter wave, infrared and laser ranging. In current closely range finding, pulse wave carries out the range finding for use in many, because pulse wave energy itself is little, and the pulse signal that reflects is weak for pulse wave range finding has the problem that the precision is low. The linear frequency modulation continuous wave has high energy, so the linear frequency modulation continuous wave is adopted for distance measurement at present, but when the linear frequency modulation continuous wave is used for distance measurement, the problems of low isolation of antenna receiving and transmitting and poor anti-interference performance exist. In the prior art, the isolation degree of the antenna transmitting part and the receiving part in the ranging system is improved by isolating the antenna transmitting part from the receiving part, but the isolation of the antenna transmitting part from the receiving part means that the volume of the ranging system is greatly increased, and the ranging system cannot be applied to the field with strict limitation on space.
Disclosure of Invention
Accordingly, the present invention is directed to a ranging system. The system adopts the linear frequency modulation continuous wave as a distance measuring medium, when the antenna transmits, the phase shift feeding treatment is carried out on the linear frequency modulation continuous wave, so that two paths of transmitting signal waves with the phase difference of 90 degrees are generated, the two paths of transmitting signal waves are reflected and then rotated and reversed, and then the phase shift feeding action is carried out to synthesize the two paths of transmitting signal waves into a receiving signal wave, thereby accurately calculating the fundamental wave frequency fbThereby accurately calculating the distance.
A ranging system, the system comprising: signal generation module, low pass filter module, power distribution module, power amplification module, antenna module, low noise amplification module, signal amplification module, mixing module, intermediate frequency filter module and signal conversion module, wherein:
the signal generation module is used for generating a linear frequency modulation continuous wave signal;
the low-pass filtering module is used for suppressing higher harmonics and out-of-band signals of the linear frequency modulation continuous wave signals generated by the signal generating module and filtering useless signals;
the power distribution module is used for dividing the signals input by the low-pass filtering module into a first path of linear frequency modulation continuous wave signals and a second path of linear frequency modulation continuous wave signals which are equal in size and consistent in phase;
the power amplification module is used for performing power amplification on the first path of linear frequency modulation continuous wave signal so that the power intensity meets the preset intensity;
the antenna module is used for transmitting the first path of linear frequency modulation continuous wave transmitting signal amplified by the power amplification module to a space and receiving a return signal; wherein the antenna module includes: the phase-shifting feed unit comprises a signal transmitting port connected with the signal transmitting unit, a signal receiving port connected with the signal receiving unit and a plurality of connecting ports connected with the radiating groups in a one-to-one corresponding manner; the transmitting signals of the signal transmitting unit generate two paths of transmitting signals after being acted by the phase-shifting feed unit, the phase difference between each path of transmitting signals is 90 degrees, and the two paths of transmitting signals are respectively and correspondingly sent to the two radiation groups and then radiated and synthesized to transmit circularly polarized waves; the two radiation groups are also used for receiving circularly polarized waves with the rotating direction opposite to that of the transmitting circularly polarized waves and respectively and correspondingly inducing a path of induction signal, the phase difference between the two paths of induction signals is 90 degrees, and the two paths of induction signals are combined into a return signal at the signal receiving port after being acted by the phase-shifting feed unit and then are transmitted to the signal receiving unit;
the transmitting frequency of the transmitting signal is ft, the return signal comprises a noise signal and a return signal, the frequency of the return signal is fr, and the frequency of the fundamental wave is fb-ft-fr;
the low-noise amplification module is used for carrying out noise reduction processing on the return signal received by the antenna module and reducing noise signal components, so that the signal-to-noise ratio is improved and a noise reduction signal is obtained;
the signal amplification module is used for receiving the second path of linear frequency modulation continuous wave signals distributed by the power distribution module and carrying out signal amplification processing on the second path of linear frequency modulation continuous wave signals;
the frequency mixing module is used for mixing the second path of linear frequency modulation continuous wave signal processed by the signal amplification module and the noise reduction signal processed by the low-noise amplification module to obtain a frequency mixing signal; the frequency-sweep bandwidth fs and the frequency-sweep time ts of the frequency-mixing signal are set.
The intermediate frequency filtering module is used for filtering signals outside an intermediate frequency band to obtain intermediate frequency band signals;
and the signal conversion module is used for converting the analog-digital signal of the intermediate frequency waveband signal, calculating the distance D according to D ═ c × ts × fb/2fs, and outputting a distance signal result.
Preferably, the working frequency band of the chirped continuous wave is an L-band.
Preferably, the low-pass filter module is one of model LFCN-1700+, LFCN-1800+, LFCN-2000+ and LFCN-2250 +.
Preferably, the frequency mixing module adopts MCA1-24MH + or SIM-43H +.
Preferably, the phase-shift feeding unit includes a 3dB bridge.
Preferably, the radiation group includes a first radiation group and a second radiation group, the first radiation group and the second radiation group both include two radiators, and a center connecting line between the two radiators of the first radiation group is perpendicular to a center connecting line between the two radiators of the second radiation group.
Preferably, the radiators of the first radiation group and the radiators of the second radiation group are arranged in a circumferential array along the center of the antenna on the cross section of the antenna, and the radiators of the first radiation group and the radiators of the second radiation group are sequentially arranged adjacently at intervals.
Preferably, the radiator includes radial paster and axial paster that connect gradually with certain contained angle, and is adjacent axial paster connect respectively in on the relative both sides limit of radial paster.
Preferably, radial paster is including end to end's first side, second side, third side and fourth side in proper order, first side with the third side is relative, the second side with the fourth side is relative, the fourth side is close to the axis setting of antenna, the second side is kept away from the axis setting of line, the fourth side with be the cockscomb structure on the second side.
In the technical scheme, the distance measuring medium adopts linear frequency modulation continuous waves, low-pass filtering is carried out on the medium by adopting the linear frequency modulation continuous waves, then power distribution is carried out on the waves, the waves are distributed into two paths of waves with equal size and consistent phase, one path of wave is transmitted to an antenna module, a phase-shifting feed unit receives a transmitting signal sent by a signal transmitting unit through a signal transmitting port, the transmitting signal is subjected to phase shifting to form two paths of constant amplitude signals with 90-degree phase difference, the two paths of constant amplitude signals are correspondingly transmitted to two radiation groups and then radiated to form two paths of electromagnetic fields which are perpendicular to each other and have 90-degree phase difference, and a left-hand circularly polarized signal (or a right-hand circularly polarized signal) is formed in space synthesis and transmitted outThe electromagnetic field generated by the first radiation group is coupled to the second radiation group, so that the coupling electromagnetic field has zero comprehensive effect formed at the signal receiving port, and the isolation of the signal transmitting port and the signal receiving port during signal transmission is realized. In addition, when receiving the receiving circular polarized wave, the rotating direction of the receiving circular polarized wave is opposite to that of the transmitting circular polarized wave, the two radiation groups respectively generate one of two receiving signals with the corresponding phase difference of 90 degrees, the two receiving signals enter the phase-shifting feed unit through the connecting port, and under the action of the phase-shifting feed unit, the phases of the two receiving signals at the signal receiving port are equal, so that the receiving signals are strengthened, and return signals are obtained, wherein the transmitting frequency of the transmitting signals is ftThe frequency of the return signal being frThen the fundamental frequency is fb＝ft-frThen the return signal is denoised and mixed with the second path of linear frequency modulation continuous wave signal amplified by the signal, and then the intermediate frequency filtering is carried out, and the sweep frequency bandwidth f of the mixed signalsSweep time of tsThen, the digital value is converted by the tape mode according to D ═ c × ts*fb/2fsThe distance D is calculated, and the ranging of the linear frequency modulation continuous wave is completed.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of a ranging system;
FIG. 2 is a schematic diagram of an antenna module;
fig. 3 is a schematic structural diagram of an antenna module;
fig. 4 is a diagram of an antenna module structure;
fig. 5 is another structural view of an antenna module;
fig. 6 is a schematic diagram of a working process of a ranging system.
Detailed Description
The following detailed description of the present invention is given for the purpose of better understanding technical solutions of the present invention by those skilled in the art, and the present description is only exemplary and explanatory and should not be construed as limiting the scope of the present invention in any way.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
It is to be understood that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like are used in a generic and descriptive sense only and not for purposes of limitation, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like are used in the generic and descriptive sense only and not for purposes of limitation, as the term is used in the generic and descriptive sense, and not for purposes of limitation, unless otherwise specified or implied, and the specific reference to a device or element is intended to be a reference to a particular element, structure, or component. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Referring to fig. 1, a ranging system includes: a signal generating module 21, a low-pass filtering module 22, a power distributing module 23, a power amplifying module 24, an antenna module 25, a low-noise amplifying module 26, a signal amplifying module 27, a mixing module 28, an intermediate frequency filtering module 29, and a signal converting module 30, wherein:
a signal generating module 21, configured to generate a Linear Frequency Modulated Continuous Wave (LFMCW) signal, which generally selects an L-band (1-2 Ghz); the low-pass filtering module 22 performs suppression of higher harmonics and out-of-band signals on the chirp continuous wave signals generated by the signal generating module 21 to filter out unwanted signals; then, the signal input by the low-pass filtering module 22 is divided into a first path of linear frequency modulation continuous wave signal and a second path of linear frequency modulation continuous wave signal which are equal in size and consistent in phase through a power distribution module 23; the first channel of chirp continuous wave signal passes through the power amplification module 24, and the power amplification processing is performed on the first channel of chirp continuous wave signal, so that the power intensity meets the preset intensity; the antenna module 25 transmits the first linear frequency modulation continuous wave transmitting signal amplified by the power amplification module 24 to the space and receives a return signal; wherein the transmission frequency of the transmission signal is ftThe frequency of the return signal being frFundamental frequency of fb＝ft-fr(ii) a In the determined transmitted and returned signals, ftAnd frIs a value that can be calculated or directly displayed, so fb＝ft-frMay also be determined. However, since the received return signal also contains an interference signal wave or a noise signal in the signal wave processing, the signal needs to be further processed to obtain a comparisonPrecise frequency f of the return signalr. The received return signal is subjected to noise reduction processing by the low-noise amplification module 26, and noise signal components are reduced, so that the signal-to-noise ratio is improved, and a noise reduction signal is obtained.
The signal amplification module 27 receives the second channel of chirp continuous wave signals distributed by the power distribution module 23, and performs signal amplification processing on the second channel of chirp continuous wave signals; the frequency mixing module 28 performs frequency mixing on the second channel of linear frequency modulation continuous wave signal processed by the signal amplification module 27 and the noise reduction signal processed by the low-noise amplification module 26 to obtain a frequency mixing signal; wherein the swept bandwidth f of the mixing signalsSweep time of tsThe mixing signal passes through an intermediate frequency filtering module 29, and signals outside the intermediate frequency band of the mixing signal are filtered out to obtain an intermediate frequency band signal; the intermediate frequency band signal is processed by the signal conversion module 30, and the intermediate frequency band signal is converted into digital signal according to fb/td＝fs/tsAnd f isb＝ft-frCan derive td＝ts*(ft-fr) /fsAnd D ═ ct d2, so D ═ c × t can be calculateds*(ft-fr)/2fsThereby completing ranging.
Referring to fig. 3, 4 and 5, the antenna module 25 includes a signal processing unit 11, a phase-shifting feeding unit 12, a signal transmitting unit 13 and a signal receiving unit 14, the signal processing unit 11 includes two vertically arranged radiation groups, i.e., a first radiation group 111 and a second radiation group 112, the phase-shifting feeding unit 12 includes a signal transmitting port 121 connected to the signal transmitting unit 13, a signal receiving port 122 connected to the signal receiving unit 14 and a plurality of connecting ports 123 connected to the radiation groups in a one-to-one correspondence manner. The transmitting signals sent by the signal transmitting unit 13 are acted by the phase-shifting feed unit 12 to generate two transmitting signals, the phase difference between the two transmitting signals is 90 degrees, the two transmitting signals are respectively and correspondingly sent to the two radiation groups, and then the electromagnetic waves radiated by the two radiation groups are spatially synthesized to form transmitting circularly polarized waves. In addition, the two radiation groups are also used for receiving circularly polarized waves with the rotation direction opposite to that of the transmitted circularly polarized waves and respectively and correspondingly inducing a path of induction signal, the phase difference between each path of induction signal is 90 degrees, the two paths of induction signals are combined into a received signal at the signal receiving port 122 after being acted by the phase-shifting feed unit 12 and transmitted to the received signal connector, and meanwhile, the phase difference between the two paths of induction signals at the signal transmitting port 121 is 180 degrees after being acted by the phase-shifting feed unit 12 so as to be mutually offset. It is understood that the signal processing unit 11, the signal transmitting unit 13, the signal receiving unit 14 and the ports of the phase-shift feeding unit 12 are connected by a microstrip line 16.
In this embodiment, when transmitting signals, the phase-shifting feeding unit 12 receives the transmission signals sent by the signal transmitting unit 13 through the signal transmitting port 121, then phase-shifts the transmission signals to form two equal amplitude signals with a phase difference of 90 °, and correspondingly sends the two equal amplitude signals to the two radiation groups to form two electromagnetic fields with a phase difference of 90 ° and perpendicular to each other, and the two electromagnetic fields are spatially synthesized to form right-handed circularly polarized signals (or right-handed circularly polarized waves) and then are transmitted. In addition, when receiving the circular polarized wave, the two radiation components respectively and correspondingly generate one of two induction signals with a phase difference of 90 degrees, the two induction signals enter the phase-shifting feed unit 12 through the connection port 123, under the phase-shifting action of the phase-shifting feed unit 12, the phases of the two induction signals at the signal receiving port 122 are equal, so that the received signals are strengthened and transmitted to the signal receiving unit 14, and on the contrary, the phases of the two received signals at the signal transmitting port 121 are opposite and offset, so that the received signals cannot be formed at the signal transmitting port 121, and the receiving and transmitting isolation during receiving the signals is realized. The antenna module 25 of the invention can still realize real-time transceiving when the transceiving is in the same frequency, and can reduce the occupation of the frequency to the bandwidth, so that the antenna module 25 occupies less frequency spectrum resources.
In the present embodiment, referring to fig. 3, the phase-shift feeding unit 12 includes a 3dB bridge. It is understood that the 3dB bridge has four ports, which are port No. 1, port No. 2, port No. 3 and port No. 4, wherein port No. 3 and port No. 4 are disposed near the signal receiving and transmitting unit, and port No. 1 and port No. 2 are disposed near the signal transmitting unit 13 and the signal receiving unit 14. In this embodiment, the port No. 1 is a signal transmitting port 121 connected to the signal transmitting unit 13, the port No. 2 is a signal receiving port 122 connected to the signal receiving unit 14, the port No. 4 is a connection port 123 connected to the first radiating group 111, and the port No. 3 is a connection port 123 connected to the second radiating group 112.
In this embodiment, when transmitting signals, after the transmitting signals are sent to port No. 1 of the 3dB bridge, signals with a phase difference of 90 ° are formed at port No. 4 and port No. 3, respectively, a 0 ° phase signal attenuated by 3dB is formed at port No. 4, and a 90 ° phase-shifted signal attenuated by 3dB is formed at port No. 3. The two paths of signals are respectively sent to the first radiation group 111 and the second radiation group 112 through the microstrip line 16 and radiated to the space, and two paths of electromagnetic fields which are perpendicular to each other and have the phase difference of 90 degrees are synthesized in the space to just form left-handed circularly polarized signals to be transmitted. It should be noted that the phase difference of 90 ° includes two cases of phase difference of +90 ° and phase difference of-90 °, and the antenna module 25 of the present invention may emit left-hand circular polarized waves or right-hand circular polarized waves, which is not limited herein.
It is emphasized that the isolation between port 1 and port 2 of the 3dB bridge is high, typically measured as 20dB, and the signal leakage from the transmit signal through port 1 of the 3dB bridge to port 2 is attenuated by approximately 20 dB. In addition, when the No. 3 port outputs the transmitting signal, the signal of the reflected signal entering the No. 2 port is also very small, and is attenuated by about-15 dB approximately. Therefore, the isolation of the signal transmitting port 121 and the signal receiving port 122 at the 3dB bridge is high.
On the other hand, since the transmission signal passes through the 3dB bridge, the microstrip line 16 is directly connected to the first radiation group 111, and the reception signal is connected to the second radiation group 112. Here, port No. 1 is directly connected to port No. 4, and port No. 2 is directly connected to port No. 3 of the 3dB bridge. The first radiation group 111 and the second radiation group 112 are perpendicular to each other, so that when the electromagnetic field generated by the first radiation group 111 is coupled to the second radiation group 112, the combined effect of the coupled electromagnetic field on the port is theoretically zero. Simulation analysis results show that the data can reach at least more than 35 dB. In view of the precision of the machining, typically 20dB can be achieved. By adopting the topological structure, the signal intensity of coupling and leakage of the transmitting signal to the signal receiving port 122 is fundamentally and greatly reduced, and experimental data analysis shows that the isolation degree of more than 15dB can be formed at least. By the scheme, the signal receiving port 122 cannot generate a transmitting signal, and the transmitting and receiving isolation is realized.
In this embodiment, when the receiving and transmitting circular polarized waves are reflected back by the obstacle 15 to form receiving circular polarized waves, the receiving circular polarized waves enter the signal processing unit 11, and equivalent "circular polarized signals" are induced in the first radiation group 111 and the second radiation group 112 that are perpendicular to each other, and after the equivalent induced currents flow out from the first radiation group 111 and the second radiation group 112, the induced currents enter the No. 4 port and the No. 3 port of the 3dB bridge, respectively, and the phase difference between the two paths of induced signals is 90 °. In this embodiment, the phase of the sensing signal of the first radiation group 111 at the port No. 4 is 0 °, and the phase of the sensing signal of the second radiation group 112 at the port No. 3 is 90 °. The induced signal of the port 4 forms a 90-degree phase signal at the port 2 after passing through the 3dB bridge, the phase of the induced signal of the port 3 is still 90 degrees on the port 2 after passing through the 3dB bridge, therefore, the signal phases of the induced signals of the port 3 and the port 4 at the port 2 after passing through the 3dB bridge are both 90 degrees, and the two 90-degree phase signals are synthesized to form a received signal. In addition, the phase of the induction signal of the port 4 is still 0 degree after passing through the 3dB bridge and the phase of the induction signal of the port 3 is 180 degrees after passing through the 3dB bridge on the port 1, and the two signals with the signal phase difference of 180 degrees are just counteracted with each other, so that a receiving signal cannot be formed on the port 1, the generation of the receiving signal at the signal transmitting port when the signal is received is avoided, and the receiving and transmitting isolation is realized.
In the embodiment, the topological network is skillfully designed, so that multiple purposes are achieved, the problem of transmitting and receiving isolation is fundamentally solved, and circularly polarized signals are formed, so that the radio range finder is not sensitive to the posture any more.
It should be noted that the center frequency of the antenna module 25 of the embodiment of the present invention is not less than 1.2GHz, the achievable bandwidth is at least 400MHz, the antenna module has an ultra-wideband characteristic, and the isolation is 15dB to 30 dB. Note that the higher the center frequency, the smaller the spatial size required. The antenna module 25 of the present embodiment can be applied to radar, and particularly, to radar ranging.
Further, referring to fig. 5, each of the first radiation group 111 and the second radiation group 112 includes two radiators, and a central connection line between the two radiators of the first radiation group 111 is perpendicular to a central connection line between the two radiators of the second radiation group 112. It should be noted that, in this embodiment, the central connection line refers to a connection line between center lines of two radiators on the cross section of the antenna module 25. The first radiation group 111 and the second radiation group 112 are formed by combining two radiators, so that the working distance can be increased on the premise of considering both the size and the cost. Preferably, the center line of the first radiation group 111 is horizontally arranged, and the center line of the second radiation group 112 is vertically arranged. In other implementations, the number of radiators of the first radiation group 111 and the number of radiators of the second radiation group 112 may also be multiple.
Preferably, the radiators of the first radiation group 111 and the radiators of the second radiation group 112 are arranged in a circumferential array along the center of the antenna module 25 on the cross section of the antenna module 25, and the radiators of the first radiation group 111 and the radiators of the second radiation group 112 are sequentially arranged at intervals. That is, the radiators of the first radiation group 111, the radiators of the second radiation group 112, and the radiators of the first radiation group 111 are sequentially arranged at intervals along the circumference. The radiators of the first radiation group 111 and the radiators of the second radiation group 112 are sequentially arranged at intervals, so that the first radiation group 111 and the second radiation group 112 form field type complementation, the size of the antenna module 25 is reduced, and the technical trend of miniaturization and integration is met.
It should be noted that the radiator may be a block, a sheet, etc., and the cross-sectional shape of the radiator may be a circle, a square, a triangle, a trapezoid, a special shape, etc. Referring to fig. 3 and 4, as an embodiment of the present invention, referring to fig. 4, each radiator includes a radial patch 113 and an axial patch 114 sequentially connected at an included angle, and adjacent axial patches 114 are respectively connected to two opposite sides of the same radial patch 113. Preferably, the radial patches 113 are arranged in multiple layers in the axial direction of the antenna module 25. Preferably, the radial patch 113 and the axial patch 114 are connected perpendicularly, facilitating the machining.
Further, referring to fig. 4 and 5, the radial patch includes a first side, a second side, a third side and a fourth side that are sequentially connected end to end, the first side is opposite to the third side, the second side is opposite to the fourth side, the fourth side is close to the axis of the antenna module 25, the second side is far away from the axis of the antenna module 25, and the fourth side and the second side are both provided with saw-toothed shapes. Preferably, the serrations are rectangular serrations. In other embodiments, the triangular saw-tooth shape is also possible. The zigzag design is beneficial to lengthening the radiation wavelength, thereby being suitable for the emission of low-frequency signals.
In addition, the antenna module 25 in the embodiment of the present invention includes the supporting structure 115, the first radiation group 111 and the second radiation group 112 are disposed in the supporting structure 115, and the outer diameter of the supporting structure 115 is preferably 25-30mm, that is, the preferred outer diameter of the antenna module 25 is 25-30mm, which illustrates that the present technical solution can enable the small antenna to have a good transceiving isolation effect, and can overcome the problem that the existing dual-function small antenna cannot have a good isolation effect while transceiving.
Referring to fig. 6, a working procedure of a distance measuring system includes: signal generator 31, low pass filter 32, power divider 33, power amplifier 34, antenna 35, signal amplifier 36, low noise amplifier 37, mixer 38, intermediate frequency filter 39, and microcontroller 40, wherein: the LFMCW signal generator 31 generates a LFMCW signal (LFMCW), which is a radio frequency microwave signal, and the LFMCW signal passes through a low pass filter 32 to suppress the high order harmonics and out-of-band of the LFMCW signal and filter out unwanted signals, and then passes through a power divider 33, which divides the input signal into two LFMCW signals with equal size and same phase, one of which enters a power amplifier 34, and the other of which enters a signal amplifier 36 to amplify the signal and then inputs the signal to a mixer 38 as a local oscillation input port of the mixer. The signal entering the power amplifier 34 amplifies the radio frequency microwave signal to a specified value, then the signal passes through the antenna 35 feed network, the electromagnetic wave energy is radiated to the space through the transmitting antenna radiator, when the electromagnetic wave meets the obstacle 41, the rotation direction of the electromagnetic wave is reversed, the reflected signal passes through the receiving antenna radiator, then the antenna feed network, the space electromagnetic wave energy is converted into the radio frequency microwave signal, the radio frequency microwave signal is transmitted into the low noise amplifier 37 for noise reduction, then the radio frequency microwave signal is input into the radio frequency microwave signal input end of the frequency mixer, the radio frequency microwave signal is mixed with the signal input into the local oscillation input end of the frequency mixer 38, the intermediate frequency signal is generated and enters the intermediate frequency filter 39, the intermediate frequency filter selects a useful signal, the useless signals except the intermediate frequency are inhibited, the intermediate frequency signal is conditioned and then is input into the microcontroller 40 with analog-to-digital, and outputting the distance signal to obtain a distance measurement result.
When the low-pass filter 32 is selected, if the highest frequency of the radio frequency microwave generated by the chirp continuous wave signal generator 31 is set to be F MHz, then the low-pass filter 32 is selected to generally select the cutoff frequency to be (F +100) MHz; for example: when the applied product works in an L wave band, the type of the filter can be selected as follows: LFCN-1700 +; LFCN-1800 +; LFCN-2000(+) and LFCN-2250(+) may be selected according to the actual situation, and when the mixer 38 is selected, a mixer with higher linearity is generally selected, and the device of the mixer 38 pays attention to the index of 1dB compression point and the index of IIP3, where 1dB compression point is greater than 5dBm and IIP3 is greater than 10 dBm; MCA1-24MH + or SIM-43H + from Mini Circuit are generally used, and the mixer can be selected according to the actual situation.
The above-described embodiments are merely illustrative, and the embodiments of the present invention may be sequentially adjusted, combined, and deleted according to actual needs.
The embodiments describe the present invention in detail, and the specific embodiments are applied to explain the structural principle and the implementation of the present invention, and the above embodiments are only used to help understand the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (8)
1. A ranging system, the system comprising: signal generation module, low pass filter module, power distribution module, power amplification module, antenna module, low noise amplification module, signal amplification module, mixing module, intermediate frequency filter module and signal conversion module, wherein:
the signal generation module is used for generating a linear frequency modulation continuous wave signal;
the low-pass filtering module is used for suppressing higher harmonics and out-of-band signals of the linear frequency modulation continuous wave signals generated by the signal generating module and filtering useless signals;
the power distribution module is used for dividing the signals input by the low-pass filtering module into a first path of linear frequency modulation continuous wave signals and a second path of linear frequency modulation continuous wave signals which are equal in size and consistent in phase;
the power amplification module is used for performing power amplification on the first path of linear frequency modulation continuous wave signal so that the power intensity meets the preset intensity;
the antenna module is used for transmitting the first path of linear frequency modulation continuous wave transmitting signal amplified by the power amplification module to a space and receiving a return signal; wherein the antenna module includes: the phase-shifting feed unit comprises a signal transmitting port connected with the signal transmitting unit, a signal receiving port connected with the signal receiving unit and a plurality of connecting ports connected with the radiating groups in a one-to-one corresponding manner; the transmitting signals of the signal transmitting unit generate two paths of transmitting signals after being acted by the phase-shifting feed unit, the phase difference between each path of transmitting signals is 90 degrees, and the two paths of transmitting signals are respectively and correspondingly sent to the two radiation groups and then radiated and synthesized to transmit circularly polarized waves; the two radiation groups are also used for receiving circularly polarized waves with the rotating direction opposite to that of the transmitting circularly polarized waves and respectively and correspondingly inducing a path of induction signal, the phase difference between the two paths of induction signals is 90 degrees, and the two paths of induction signals are combined into a return signal at the signal receiving port after being acted by the phase-shifting feed unit and then are transmitted to the signal receiving unit;
the transmission frequency of the transmission signal is ftSaid return signal having a frequency frFundamental frequency of fb＝ft-fr；
The low-noise amplification module is used for carrying out noise reduction processing on the return signal received by the antenna module and reducing noise signal components, so that the signal-to-noise ratio is improved and a noise reduction signal is obtained;
the signal amplification module is used for receiving the second path of linear frequency modulation continuous wave signals distributed by the power distribution module and carrying out signal amplification processing on the second path of linear frequency modulation continuous wave signals;
the frequency mixing module is used for mixing the second path of linear frequency modulation continuous wave signal processed by the signal amplification module and the noise reduction signal processed by the low-noise amplification module to obtain a frequency mixing signal; swept bandwidth f of the mixing signalsSweep time of ts；
The intermediate frequency filtering module is used for filtering signals outside an intermediate frequency band to obtain intermediate frequency band signals;
the signal conversion module is used for converting the analog-digital signals of the intermediate frequency wave band signals according to D ═ c × (t)s*fb/2fsCalculating the distance D and outputting a distance signal result;
the radiation group comprises a first radiation group and a second radiation group, the first radiation group and the second radiation group both comprise two radiators, and a central connecting line between the two radiators of the first radiation group is perpendicular to a central connecting line between the two radiators of the second radiation group.
2. The range finding system of claim 1, wherein: and the working frequency band of the linear frequency modulation continuous wave is an L wave band.
3. The range finding system of claim 2, wherein: the low-pass filtering module adopts one of LFCN-1700+, LFCN-1800+, LFCN-2000+ and LFCN-2250 +.
4. The range finding system of claim 1, wherein: the frequency mixing module adopts MCA1-24MH + or SIM-43H +.
5. The range finding system of claim 1, wherein: the phase-shift feed unit includes a 3dB bridge.
6. The range finding system of claim 1, wherein the radiators of the first radiation group and the radiators of the second radiation group are arranged in a circumferential array along a center of the antenna on a cross section of the antenna, and the radiators of the first radiation group and the radiators of the second radiation group are sequentially and adjacently disposed at intervals.
7. The range finding system of claim 6, wherein: the radiator comprises a radial patch and an axial patch which are sequentially connected at a certain included angle, and the axial patches are adjacent to each other and are respectively connected to two opposite side edges of the radial patch.
8. The range finding system of claim 7, wherein: radial paster is including end to end's first side, second side, third side and fourth side in proper order, first side with the third side is relative, the second side with the fourth side is relative, the fourth side is close to the axis setting of antenna, the second side is kept away from the axis setting of line, the fourth side with be the cockscomb structure on the second side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811271538.0A CN109283518B (en) | 2018-10-29 | 2018-10-29 | Distance measuring system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811271538.0A CN109283518B (en) | 2018-10-29 | 2018-10-29 | Distance measuring system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109283518A CN109283518A (en) | 2019-01-29 |
| CN109283518B true CN109283518B (en) | 2020-12-04 |
Family
ID=65174597
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811271538.0A Active CN109283518B (en) | 2018-10-29 | 2018-10-29 | Distance measuring system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109283518B (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1802554A (en) * | 2003-04-25 | 2006-07-12 | Vega格里沙贝两合公司 | Radar filling level measurement using circularly polarized waves |
| CN101876707A (en) * | 2009-12-21 | 2010-11-03 | 薛良金 | Millimeter wave/infrared composite detection radar |
| US20110175771A1 (en) * | 2007-05-08 | 2011-07-21 | Raney Russell K | Synthetic Aperture Radar Hybrid-Quadrature-Polarity Method and Architecture for Obtaining the Stokes Parameters of Radar Backscatter |
| CN201965232U (en) * | 2010-12-20 | 2011-09-07 | 河北珠峰仪器仪表设备有限公司 | High-sweeping-linearity range-measuring circuit of frequency modulation continuous wave (FMCW) radar |
| CN102393512A (en) * | 2011-09-28 | 2012-03-28 | 中国电子科技集团公司第十研究所 | Single-antenna frequency-modulated continuous-wave radar radio frequency passive cancellation method |
| CN103558598A (en) * | 2013-11-04 | 2014-02-05 | 深圳市翌日科技有限公司 | Accurate positioning method based on linear frequency modulation continuous wave technology and accurate positioning devices based on linear frequency modulation continuous wave technology |
| CN104076352A (en) * | 2014-06-27 | 2014-10-01 | 电子科技大学 | Low-interception speed measurement method and radar device |
| CN204925384U (en) * | 2015-07-21 | 2015-12-30 | 南京信息工程大学 | Millimeter wave radar ranging system |
| CN107004961A (en) * | 2017-01-22 | 2017-08-01 | 深圳市大疆创新科技有限公司 | Two-dimensional antenna system, the method and apparatus for positioning target |
| CN107580682A (en) * | 2015-05-13 | 2018-01-12 | 罗伯特·博世有限公司 | Radar sensor for motor vehicle |
| CN107607923A (en) * | 2017-08-21 | 2018-01-19 | 上海交通大学 | Vibration monitor system and signal processing method based on LFMCW radars |
| CN108474840A (en) * | 2016-01-22 | 2018-08-31 | 德克萨斯仪器股份有限公司 | Digital compensation for the mismatch in radar system |
-
2018
- 2018-10-29 CN CN201811271538.0A patent/CN109283518B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1802554A (en) * | 2003-04-25 | 2006-07-12 | Vega格里沙贝两合公司 | Radar filling level measurement using circularly polarized waves |
| US20110175771A1 (en) * | 2007-05-08 | 2011-07-21 | Raney Russell K | Synthetic Aperture Radar Hybrid-Quadrature-Polarity Method and Architecture for Obtaining the Stokes Parameters of Radar Backscatter |
| CN101876707A (en) * | 2009-12-21 | 2010-11-03 | 薛良金 | Millimeter wave/infrared composite detection radar |
| CN201965232U (en) * | 2010-12-20 | 2011-09-07 | 河北珠峰仪器仪表设备有限公司 | High-sweeping-linearity range-measuring circuit of frequency modulation continuous wave (FMCW) radar |
| CN102393512A (en) * | 2011-09-28 | 2012-03-28 | 中国电子科技集团公司第十研究所 | Single-antenna frequency-modulated continuous-wave radar radio frequency passive cancellation method |
| CN103558598A (en) * | 2013-11-04 | 2014-02-05 | 深圳市翌日科技有限公司 | Accurate positioning method based on linear frequency modulation continuous wave technology and accurate positioning devices based on linear frequency modulation continuous wave technology |
| CN104076352A (en) * | 2014-06-27 | 2014-10-01 | 电子科技大学 | Low-interception speed measurement method and radar device |
| CN107580682A (en) * | 2015-05-13 | 2018-01-12 | 罗伯特·博世有限公司 | Radar sensor for motor vehicle |
| CN204925384U (en) * | 2015-07-21 | 2015-12-30 | 南京信息工程大学 | Millimeter wave radar ranging system |
| CN108474840A (en) * | 2016-01-22 | 2018-08-31 | 德克萨斯仪器股份有限公司 | Digital compensation for the mismatch in radar system |
| CN107004961A (en) * | 2017-01-22 | 2017-08-01 | 深圳市大疆创新科技有限公司 | Two-dimensional antenna system, the method and apparatus for positioning target |
| CN107607923A (en) * | 2017-08-21 | 2018-01-19 | 上海交通大学 | Vibration monitor system and signal processing method based on LFMCW radars |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109283518A (en) | 2019-01-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8237604B2 (en) | Virtual beam forming in ultra wideband systems | |
| CN103064080B (en) | Target guiding radar with continuous waves | |
| Methfessel et al. | Design of a balanced-fed patch-excited horn antenna at millimeter-wave frequencies | |
| CN109728445A (en) | Three frequency range observing and controlling remote sensing of one kind, which are defended, leads to multi-functional compound feed | |
| CN203606490U (en) | Receiving front end of radar array employing WIFI as outer radiation source | |
| CN110568430B (en) | Non-blind area ranging method and system for monopulse radar with protection channel | |
| CN104777467B (en) | Object detection method based on frequency scan antenna | |
| CN109361061B (en) | Antenna with a shield | |
| CN107317091B (en) | Archimedes spiral antenna device for airborne ground penetrating radar | |
| CN106772335A (en) | Towards the active alien frequencies receiving type microwave radar systems of large scale structure deformation monitoring | |
| Ma et al. | A wideband dual-circularly polarized, simultaneous transmit and receive (STAR) antenna array for integrated sensing and communication in IoT | |
| CN109283518B (en) | Distance measuring system | |
| CN114280588A (en) | Microwave photon multi-band array radar implementation method and system | |
| Elhefnawy | Design and simulation of an analog beamforming phased array antenna | |
| Statnikov et al. | A 240-GHz circularly polarized FMCW radar based on a SiGe transceiver with a lens-coupled on-chip antenna | |
| CN113589273A (en) | Millimeter wave/infrared active and passive imaging detection device and method | |
| CN109283519B (en) | Based on LFMCW ranging system | |
| Kim et al. | A dual-band FMCW radar for through-wall detection | |
| US5493303A (en) | Monopulse transceiver | |
| CN108896965B (en) | 200GHz frequency band signal receiving and transmitting measurement system | |
| Engelbertz et al. | 60 GHz low phase noise radar front-end design for the detection of micro drones | |
| Shi et al. | W-band dielectric lens horn antenna and FMCW circuit module for SAR imaging radar | |
| CN111638504B (en) | Continuous wave radar front end | |
| Grüner et al. | Enhancing angle estimation accuracy of ultra compact two-channel radar MMICs at 160 GHz using a biomimetic antenna array | |
| CN112701481A (en) | Double-frequency transmitting-receiving shared antenna |
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 |