CN111948640A - Water level and flow rate integrated measuring meter - Google Patents
Water level and flow rate integrated measuring meter Download PDFInfo
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- CN111948640A CN111948640A CN202010803068.9A CN202010803068A CN111948640A CN 111948640 A CN111948640 A CN 111948640A CN 202010803068 A CN202010803068 A CN 202010803068A CN 111948640 A CN111948640 A CN 111948640A
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- water level
- flow rate
- frequency
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 56
- 230000003321 amplification Effects 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 4
- 238000005070 sampling Methods 0.000 claims description 4
- 238000001228 spectrum Methods 0.000 claims description 4
- 230000001629 suppression Effects 0.000 claims description 4
- 238000005259 measurement Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000012544 monitoring process Methods 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 230000006855 networking Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- 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
- G01S13/50—Systems of measurement based on relative movement of target
- G01S13/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
- G01S13/583—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves and based upon the Doppler effect resulting from movement of targets
- G01S13/584—Velocity or trajectory determination systems; Sense-of-movement determination systems using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves and based upon the Doppler effect resulting from movement of targets adapted for simultaneous range and velocity measurements
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/28—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring the variations of parameters of electromagnetic or acoustic waves applied directly to the liquid or fluent solid material
- G01F23/284—Electromagnetic waves
Abstract
The invention discloses a water level and flow rate integrated measuring meter, which comprises: the antenna comprises a first transceiving antenna group, a second transceiving antenna group and a signal processor; the first transceiving antenna group comprises a first transmitting antenna and a first receiving antenna, and the second transceiving antenna group comprises a second transmitting antenna and a second receiving antenna; wherein the axis of the first transmitting antenna is vertical to the water surface to be measured; the axis of the second transmitting antenna and the water surface to be measured form a preset included angle; the signal processor is electrically connected with the first transmitting antenna, the first receiving antenna, the second transmitting antenna and the second receiving antenna, and can calculate the current water level according to the signals received by the first receiving antenna and calculate the current flow rate according to the signals received by the second receiving antenna.
Description
Technical Field
The invention relates to the field of radars, in particular to a water level and flow rate integrated measuring meter.
Background
The water level and the flow velocity respectively refer to the height of the radar from the water surface and the flow velocity of liquid, and are important components for knowing river information.
As shown in fig. 1 to 3, the conventional water level and flow rate measurement can be performed using two radars. When measuring the water level, one radar sends and receives signals in the vertical direction, the water level information is calculated according to the frequency difference of receiving and transmitting, and when measuring the flow rate, the other radar sets the transmitting and receiving angles according to the actual situation and calculates the flow rate information according to the Doppler effect.
Obviously, because two radars are adopted to measure the water level and the flow rate respectively, the device has the defects of inconvenient debugging, larger occupied space, high cost and the like.
Disclosure of Invention
The embodiment of the invention provides a water level and flow rate integrated meter, which can realize the measurement of water level and flow rate simultaneously by using one radar.
The embodiment of the invention provides a water level and flow rate integrated measuring meter, which comprises: the antenna comprises a first transceiving antenna group, a second transceiving antenna group and a signal processor; the first transceiving antenna group comprises a first transmitting antenna and a first receiving antenna, and the second transceiving antenna group comprises a second transmitting antenna and a second receiving antenna; wherein the axis of the first transmitting antenna is vertical to the water surface to be measured; the axis of the second transmitting antenna and the water surface to be measured form a preset included angle; the signal processor is electrically connected with the first transmitting antenna, the first receiving antenna, the second transmitting antenna and the second receiving antenna, and can calculate the current water level according to the signals received by the first receiving antenna and calculate the current flow rate according to the signals received by the second receiving antenna.
Preferably, the included angle between the axis of the second transmitting antenna and the water surface to be measured is 15-60 degrees.
Preferably, the signal transmitted by the first transmitting antenna is a frequency modulated continuous wave signal:
wherein f iscThe carrier frequency of the frequency modulated continuous wave is shown, wherein B is the bandwidth of the frequency modulated continuous wave, and T is the pulse width.
Preferably, the first receiving antenna beam width is 26 ° + 10 °, gain 15 dBi; frequency modulated continuous wave signal s1(t) after reflection by the target, the echo signal is represented as:
wherein, tdAre time intervals.
Preferably, the beam width of the second transmitting antenna is 8 degrees, and the transmitting frequency is dot frequency between 76G and 78G;
the signal transmitted by the second transmitting antenna is a single-frequency sine wave signal:
s2(t)＝Asin(2πf0t+β)；
wherein f is0Is the frequency of the transmitted signal and β is the initial phase.
Preferably, the beam width of the second receiving antenna is 60 °. 10 °; single-frequency sine wave signal s2(t) after reflection by the target, the echo signal is represented as:
r2(t)＝Asin(2πf0(t-τ)+β)；
wherein τ is the time delay.
Preferably, the signal processor is specifically configured to:
carrying out harmonic mixing, amplification and low-pass filtering on the received echo signals, outputting difference frequency signals containing distance information, and forming difference frequency digital signals through A/D sampling;
performing FFT, clutter suppression, target detection and spectrum estimation processing on the difference frequency digital signal to obtain Doppler frequency shift;
and calculating the water level or the flow velocity according to the Doppler frequency shift.
Preferably, the first transceiver antenna group and the second transceiver antenna group operate in a time-sharing manner.
Preferably, the first transceiving antenna group and the second transceiving antenna group adopt 77G microstrip antennas, and are covered with antenna covers.
Preferably, the mobile terminal further comprises a power supply and a wireless communication module, wherein the power supply and the wireless communication module are electrically connected with the signal processor.
The water level and flow rate integrated meter provided by the embodiment of the invention integrates the two receiving and transmitting antenna groups at the same time and controls the two receiving and transmitting antenna groups to work in a time-sharing manner, so that the monitoring of the water level and the flow rate can be completed by utilizing one radar.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic view of the measurement principle of a conventional radar odometer.
Fig. 2 is a schematic view of an antenna plate of the water level ranging radar of fig. 1.
Fig. 3 is a schematic view of an antenna board of the flow velocity measurement radar of fig. 1.
FIG. 4 is a hardware diagram of the integrated water level and flow rate meter according to the embodiment of the present invention.
Fig. 5 is a measurement schematic diagram of the water level and flow rate integrated meter provided by the embodiment of the invention.
FIG. 6 is another schematic diagram of the water level and flow rate integrated meter according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 4, an embodiment of the present invention provides an integrated water level and flow rate meter 100, including: a first transceiving antenna group 10, a second transceiving antenna group 20, and a signal processor 30; wherein, the first transceiving antenna group 10 comprises a first transmitting antenna 11 and a first receiving antenna 12, and the second transceiving antenna group 20 comprises a second transmitting antenna 21 and a second receiving antenna 22; wherein, the axis of the first transmitting antenna 11 is vertical to the water surface to be measured; the axis of the second transmitting antenna 21 and the water surface to be measured form a preset included angle; the signal processor 30 is electrically connected to the first transmitting antenna 11, the first receiving antenna 12, the second transmitting antenna 21 and the second receiving antenna 22, and can calculate the current water level according to the signal received by the first receiving antenna 12 and calculate the current flow rate according to the signal received by the second receiving antenna 22.
Specifically, in this embodiment, the signal processor 30 controls the first transceiver antenna group 10 and the second transceiver antenna group 20 to operate in a time-sharing manner, that is, the direct operating states of the first transceiver antenna group 10 and the second transceiver antenna group 20 are switched at predetermined intervals, so that at most one transceiver antenna group is in an operating state in any time period.
In this embodiment, when the water level needs to be measured, that is, when the first transceiver antenna group 10 is in the working state, as shown in fig. 5 and 6, the transmitting direction of the first transmitting antenna 11 is perpendicular to the water level. The first transmitting antenna 11 transmits a frequency modulated continuous wave signal
Wherein f iscIs the carrier frequency of a frequency modulated continuous wave, where B is the frequency modulated continuous waveThe bandwidth of the wave, T, is the pulse width. The beam width of the frequency modulated continuous wave signal is: horizontal 8 degrees and vertical 8 degrees. The antenna gain is 19dBi, the maximum transmit power is 10dBm, and the ERIP is 29 dBm.
In this embodiment, the beam width of the first receiving antenna 12 may be 26 ° by 10 °, and the gain is 15 dBi. The frequency-modulated continuous wave signal s emitted by the first transmitting antenna 111(t) after reflection off the target (i.e. the water surface), the echo signal is represented as
Wherein t isdAre time intervals. Of course, it should be noted that in other embodiments of the present invention, the beam width of the first receiving antenna 12 may be adjusted according to actual needs, for example, adjusted to 30 ° by 8 °, and these schemes are all within the protection scope of the present invention.
In this embodiment, after receiving the echo signal of the first receiving antenna 12, the signal processor 30 sequentially performs harmonic mixing, amplification, and low-pass filtering on the echo signal, outputs a difference frequency signal including distance information, forms a difference frequency digital signal through a/D sampling, performs FFT, clutter suppression, target detection, spectrum estimation, and the like on the difference frequency digital signal, obtains a doppler shift, and can calculate and obtain high-precision water level data according to the doppler shift.
In this embodiment, when the flow rate needs to be measured, that is, when the second transceiving antenna group 20 is in the working state, as shown in fig. 3 and 4, the transmitting direction of the second transmitting antenna 21 forms a predetermined angle with the water surface, for example, the angle is between 15 ° and 60 °. At this time, the beam width of the second transmitting antenna 21 is 8 °, and the transmitting frequency is dot frequency between 76G and 78G;
the signal transmitted by the second transmitting antenna 21 is a single-frequency sine wave signal:
s2(t)＝Asin(2πf0t+β)；
wherein f is0Is the frequency of the transmitted signal and β is the initial phase.
In the present embodiment, the beam width of the second receiving antenna 22 is 60 ° by 10 °. It is composed ofA single-frequency sine wave signal s transmitted by the second transmitting antenna 212(t) after reflection off the target (i.e., the water surface), the echo signal is expressed as:
r2(t)＝Asin(2πf0(t-τ)+β)；
wherein τ is the time delay. Of course, it should be noted that in other embodiments of the present invention, the beam width of the second receiving antenna 22 may be adjusted according to actual needs, such as 60 ° by 8 °, and these schemes are all within the protection scope of the present invention.
In this embodiment, after receiving the echo signal of the second receiving antenna 22, the signal processor 30 sequentially performs harmonic mixing, amplification and low-pass filtering on the echo signal, outputs a difference frequency signal including distance information, forms a difference frequency digital signal through a/D sampling, performs FFT, clutter suppression, target detection, spectrum estimation and other processing on the difference frequency digital signal, obtains a doppler shift, and can calculate and obtain high-precision water level data according to the doppler shift.
Preferably, in this embodiment, the first transceiver antenna group 10 and the second transceiver antenna group 20 adopt 77G microstrip antennas, and are covered with antenna covers.
Preferably, in this embodiment, the device further includes a power source 40 and a wireless communication module 50, and both the power source 40 and the wireless communication module 50 are electrically connected to the signal processor 30.
The power source 40 is used for supplying electric energy required for the operation of the whole device, and may be a lithium battery or the like. Wireless communication module 50 can be 4/5G module, wifi module or thing networking communication module etc. and it can calculate water level and the velocity of flow information that obtains with signal processor 30 and send to long-range server or user terminal to the user can real-timely know the information of monitoring.
In summary, the water level and flow rate integrated meter provided by the embodiment of the invention integrates two sets of transceiver antenna groups on the same radar antenna plate, and controls the two sets of transceiver antenna groups to work in a time-sharing manner through the signal processor 30, so that the monitoring of the water level and the flow rate can be completed by using one radar.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. An integrated water level and flow rate meter, comprising: the antenna comprises a first transceiving antenna group, a second transceiving antenna group and a signal processor; the first transceiving antenna group comprises a first transmitting antenna and a first receiving antenna, and the second transceiving antenna group comprises a second transmitting antenna and a second receiving antenna; wherein the axis of the first transmitting antenna is vertical to the water surface to be measured; the axis of the second transmitting antenna and the water surface to be measured form a preset included angle; the signal processor is electrically connected with the first transmitting antenna, the first receiving antenna, the second transmitting antenna and the second receiving antenna, and can calculate the current water level according to the signals received by the first receiving antenna and calculate the current flow rate according to the signals received by the second receiving antenna.
2. The water level and flow rate integrated meter according to claim 1, wherein the axis of the second transmitting antenna forms an angle of 15 ° to 60 ° with the water surface to be measured.
3. The water level and flow rate integral meter according to claim 1, wherein the signal transmitted by the first transmitting antenna is a frequency modulated continuous wave signal:
wherein f iscThe carrier frequency of the frequency modulated continuous wave is shown, wherein B is the bandwidth of the frequency modulated continuous wave, and T is the pulse width.
4. The water level and flow rate integrated meter according to claim 3, wherein the first receiving antenna has a beam width of 26 ° + 10 °, and a gain of 15 dBi; frequency modulated continuous wave signal s1(t) after reflection by the target, the echo signal is represented as:
wherein, tdAre time intervals.
5. The water level and flow rate integrated meter according to claim 2, wherein the second transmitting antenna has a beam width of 8 ° and a transmitting frequency of 76G to 78G;
the signal transmitted by the second transmitting antenna is a single-frequency sine wave signal:
s2(t)＝Asin(2πf0t+β)；
wherein f is0Is the frequency of the transmitted signal and β is the initial phase.
6. The water level and flow rate integrated meter according to claim 5, wherein the second receiving antenna has a beam width of 60 ° by 10 °; single-frequency sine wave signal s2(t) after reflection by the target, the echo signal is represented as:
r2(t)＝Asin(2πf0(t-τ)+β)；
wherein τ is the time delay.
7. The water level and flow rate integrated meter according to claims 1 to 6, wherein the signal processor is specifically configured to:
carrying out harmonic mixing, amplification and low-pass filtering on the received echo signals, outputting difference frequency signals containing distance information, and forming difference frequency digital signals through A/D sampling;
performing FFT, clutter suppression, target detection and spectrum estimation processing on the difference frequency digital signal to obtain Doppler frequency shift;
and calculating the water level or the flow velocity according to the Doppler frequency shift.
8. The water level and flow rate integrated meter according to any one of claims 1 to 6, wherein the first transceiver antenna group and the second transceiver antenna group operate in a time-sharing manner.
9. The water level and flow rate integrated meter according to any one of claims 1 to 6, wherein the first and second transceiver antenna groups employ 77G microstrip antennas and are covered with antenna covers.
10. The water level and flow rate integrated meter according to any one of claims 1 to 6, further comprising a power supply and a wireless communication module, both of which are electrically connected to the signal processor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202010803068.9A CN111948640A (en) | 2020-08-11 | 2020-08-11 | Water level and flow rate integrated measuring meter |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010803068.9A CN111948640A (en) | 2020-08-11 | 2020-08-11 | Water level and flow rate integrated measuring meter |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060220946A1 (en) * | 2004-12-24 | 2006-10-05 | Nec Corporation | Interferometer-type radar |
| CN104849491A (en) * | 2015-04-28 | 2015-08-19 | 奇瑞汽车股份有限公司 | Water flow velocity detection method and system |
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| US20170016984A1 (en) * | 2015-07-14 | 2017-01-19 | U&U Engineering Inc. | Device for Measuring Surface Speed and Liquid Level of Fluid |
| CN107845860A (en) * | 2016-09-21 | 2018-03-27 | 北京行易道科技有限公司 | Antenna system and radar |
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| CN109001723A (en) * | 2018-06-29 | 2018-12-14 | 薛志勇 | Radar current meter |
| CN109557531A (en) * | 2018-11-21 | 2019-04-02 | 南京微麦科斯电子科技有限责任公司 | A kind of high-resolution river radar installations based on phased-array technique |
| CN110596699A (en) * | 2019-08-30 | 2019-12-20 | 厦门四信通信科技有限公司 | Method, device and equipment for measuring water level flow velocity based on radar |
-
2020
- 2020-08-11 CN CN202010803068.9A patent/CN111948640A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060220946A1 (en) * | 2004-12-24 | 2006-10-05 | Nec Corporation | Interferometer-type radar |
| CN104849491A (en) * | 2015-04-28 | 2015-08-19 | 奇瑞汽车股份有限公司 | Water flow velocity detection method and system |
| US20170016984A1 (en) * | 2015-07-14 | 2017-01-19 | U&U Engineering Inc. | Device for Measuring Surface Speed and Liquid Level of Fluid |
| CN205102883U (en) * | 2015-09-28 | 2016-03-23 | 内蒙古信源信息技术有限公司 | Novel radar fluviograph |
| CN106093929A (en) * | 2016-05-27 | 2016-11-09 | 南京微麦科斯电子科技有限责任公司 | A kind of radar installations measuring river flow velocity |
| CN107845860A (en) * | 2016-09-21 | 2018-03-27 | 北京行易道科技有限公司 | Antenna system and radar |
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| CN207817193U (en) * | 2018-03-02 | 2018-09-04 | 中船重工西安海澜装备技术有限公司 | Radar range finding circuit |
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