CN219777917U

CN219777917U - Composite microwave radar system with blanking and material level fluctuation state detection functions

Info

Publication number: CN219777917U
Application number: CN202321179644.2U
Authority: CN
Inventors: 呼秀山; 李圆圆; 韩玉
Original assignee: Beijing Ruida Instrument Co ltd
Current assignee: Beijing Ruida Instrument Co ltd
Priority date: 2023-05-16
Filing date: 2023-05-16
Publication date: 2023-09-29
Anticipated expiration: 2033-05-16

Abstract

The application provides a composite microwave radar system with blanking and material level fluctuation state detection functions, which comprises: the signal receiving and transmitting module is used for transmitting a fixed frequency microwave signal and a continuous frequency modulation microwave signal, receiving a Doppler signal and a ranging echo signal and uploading the Doppler signal and the ranging echo signal to the measuring module; the measuring module is used for generating a fixed frequency microwave signal and a continuous frequency modulation microwave signal according to the fixed frequency signal and the continuous frequency modulation signal issued by the control module and issuing the fixed frequency microwave signal and the continuous frequency modulation microwave signal to the signal receiving and transmitting module, receiving a Doppler signal and a ranging echo signal and uploading the Doppler signal and the ranging echo signal to the control module; the control module is used for alternately generating a fixed frequency signal and a continuous frequency modulation signal and obtaining a blanking state, a material level fluctuation state and/or a material level distance according to the Doppler signal and the ranging echo signal. The application solves the problem that the existing radar measurement system is difficult to obtain the high-precision material level value and the blanking state of the container, not only can obtain the precision material level distance, but also can identify the blanking state and the material level fluctuation state.

Description

Composite microwave radar system with blanking and material level fluctuation state detection functions

Technical Field

The embodiment of the utility model relates to the technical field of industrial measurement, in particular to a composite microwave radar system with blanking and material level fluctuation state detection functions.

Background

The radar measurement system has the advantages of safety, high efficiency, environmental protection and the like, so that the radar measurement system is widely popularized and applied in the industrial fields of material level monitoring and the like of materials in a container.

However, under some monitoring conditions, the material level of the material is affected by process factors such as stirring and vibration to generate fluctuation or even vibration, at this time, the material level reflected echo signals received by the existing radar measurement system are weak, and a large amount of interference echo signals are received by the radar measurement system together with the material level reflected echo signals, so that the existing radar measurement system can hardly effectively judge the material level reflected echo signals, and cannot obtain a high-precision material level value according to the material level reflected echo signals. In addition, the conventional radar measurement system is limited by conditions such as a measurement principle, and the blanking state of a container, such as the blanking state of a pipeline in the container, is difficult to identify.

Disclosure of Invention

The embodiment of the utility model provides a composite microwave radar system with blanking and material level fluctuation state detection functions, which is used for acquiring a precise material level distance and effectively identifying a blanking state and a material level fluctuation state.

The embodiment of the utility model provides a composite microwave radar system with blanking and material level fluctuation state detection functions, which comprises a control module, a measuring module and a signal receiving and transmitting module;

the signal receiving and transmitting module is connected with the measuring module and used for transmitting fixed-frequency microwave signals and continuous frequency modulation microwave signals; receiving Doppler signals and ranging echo signals and uploading the Doppler signals and the ranging echo signals to the measurement module;

the measuring module is connected with the control module and is used for generating the fixed frequency microwave signal and the continuous frequency modulation microwave signal according to the fixed frequency signal and the continuous frequency modulation signal issued by the control module and issuing the fixed frequency microwave signal and the continuous frequency modulation microwave signal to the signal receiving and transmitting module; and receiving the Doppler signal and the ranging echo signal and uploading the Doppler signal and the ranging echo signal to the control module;

the control module is used for alternately generating the fixed frequency signal and the continuous frequency modulation signal; and obtaining at least one of a blanking state, a material level fluctuation state and a material level distance according to the Doppler signal and the ranging echo signal;

the measuring module at least comprises a Doppler measuring module, wherein the Doppler measuring module is connected between the control module and the signal receiving and transmitting module and is used for generating the fixed frequency microwave signal according to the fixed frequency signal issued by the control module and issuing the fixed frequency microwave signal to the signal receiving and transmitting module; and receiving the Doppler signal uploaded by the signal receiving and transmitting module and uploading the Doppler signal to the control module.

Optionally, the pipe blanking state includes a blocking state, a venting state, and a flow state;

the level distance comprises a material distance value and/or a stirring structure distance value.

Optionally, the characteristic information of the doppler signal includes at least one of a level change speed of the material, a rotation speed and period of the stirring structure, a fluctuation degree of the level, or a flowing state of the material;

the characteristic information of the ranging echo signals at least comprises a target echo signal formed by the reflection of the materials, a disturbance echo signal formed by the reflection of the stirring structure and an interference echo signal formed by the reflection of an interfering object.

Optionally, the measurement module further comprises a ranging module;

the distance measuring module is connected between the control module and the signal receiving and transmitting module and is used for generating the continuous frequency modulation microwave signal according to the continuous frequency modulation signal issued by the control module and issuing the continuous frequency modulation microwave signal to the signal receiving and transmitting module; and receiving the ranging echo signals uploaded by the signal receiving and transmitting module and uploading the ranging echo signals to the control module.

Optionally, the signal transceiver module includes a common antenna structure that is common to the doppler measurement module and the ranging module;

Alternatively, the signal transceiver module includes a first antenna structure and a second antenna structure; the first antenna structure is connected with the Doppler measurement module and is used for transmitting the fixed frequency microwave signal, receiving the Doppler signal and uploading the Doppler signal to the Doppler measurement module; the second antenna structure is connected with the ranging module and used for transmitting the continuous frequency modulation microwave signals, receiving the ranging echo signals and uploading the ranging echo signals to the ranging module.

Optionally, the control module comprises a micro control unit, an AD collector, an amplifier and a microwave unit;

the microwave unit is respectively connected with the measuring module, the micro control unit and the amplifier and is used for alternately generating the fixed frequency signal and the continuous frequency modulation signal according to the control parameters issued by the micro control unit and issuing the signals to the measuring module; the Doppler signal and the ranging echo signal uploaded by the measuring module are received, a first mixed signal is generated according to the Doppler signal, a second mixed signal is generated according to the ranging echo signal, and then the first mixed signal and the second mixed signal are transmitted to the amplifier;

The micro control unit is connected with the amplifier through the AD collector and is used for acquiring characteristic information of the Doppler signal and the ranging echo signal according to the first mixed signal and the second mixed signal which are amplified by the amplifier and subjected to signal conversion through the AD collector, so that at least one of the blanking state, the material level fluctuation state and the material level distance is acquired.

Optionally, the microwave unit includes a mixer and a local oscillator circuit;

the local oscillation circuit is connected with the mixer and used for generating local oscillation signals and transmitting the local oscillation signals to the mixer;

the mixer is connected between the amplifier and the measurement module and is used for receiving the Doppler signals and the ranging echo signals uploaded by the measurement module; and mixing the local oscillation signal and the Doppler signal to obtain a first mixed signal, mixing the local oscillation signal and the ranging echo signal to obtain a second mixed signal, and transmitting the first mixed signal and the second mixed signal to the amplifier.

Optionally, the microwave unit generates at least 8 continuous frequency modulation signals at equal intervals, and the total frequency modulation time of the continuous frequency modulation signals is longer than 10ms.

Optionally, the micro control unit is further configured to perform two-dimensional fourier transform on at least 8 second mixed signals after being amplified by the amplifier and subjected to signal conversion by the AD collector, so as to obtain a plurality of velocity echo curves.

Optionally, the micro control unit obtains the level fluctuation state and/or the level distance according to the plurality of velocity echo curves and the characteristic information of the doppler signal.

Optionally, the control module obtains the level fluctuation state and/or the level distance according to the ranging echo signal and the rotation speed and period of the stirring structure.

Optionally, the control module obtains the level fluctuation state and/or the level distance according to the ranging echo signal and the fluctuation degree of the level of the material.

Optionally, the control module obtains the blanking state according to the ranging echo signal and the flow state of the material.

Optionally, the method further comprises:

the display module is connected with the control module and is at least used for displaying one of the blanking state, the material level fluctuation state and the material level distance;

and the power supply module is connected with the control module and used for accessing external power supply and converting the external power supply into multi-stage working voltage so as to maintain the normal operation of the composite microwave radar system.

According to the technical scheme provided by the embodiment of the utility model, the control module alternately generates the fixed frequency signal and the continuous frequency modulation signal; the measurement module generates a fixed frequency microwave signal and a continuous frequency modulation microwave signal according to the fixed frequency signal and the continuous frequency modulation signal issued by the control module and issues the fixed frequency microwave signal and the continuous frequency modulation microwave signal to the signal receiving and transmitting module; the signal receiving and transmitting module transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal; the signal receiving and transmitting module receives Doppler signals and ranging echo signals and uploads the Doppler signals and the ranging echo signals to the measuring module; the measuring module receives Doppler signals and ranging echo signals and uploads the Doppler signals and the ranging echo signals to the control module; the control module obtains the blanking state, the material level fluctuation state and/or the material level distance according to the Doppler signal and the ranging echo signal, solves the problems that the existing radar measurement system cannot obtain a high-precision material level value and is difficult to identify the blanking state of a container, can obtain the precise material level distance according to the Doppler signal and the ranging echo signal, and can effectively identify the blanking state and the material level fluctuation state.

Drawings

Fig. 1 is a schematic structural diagram of a composite microwave radar system with blanking and level fluctuation state detection functions according to an embodiment of the present utility model;

FIG. 2 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation state detection functions according to an embodiment of the present utility model;

FIG. 3 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation detection functions according to an embodiment of the present utility model;

fig. 4 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation state detection functions according to an embodiment of the present utility model.

Detailed Description

The utility model is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present utility model are shown in the drawings.

Just as the prior radar measurement system mentioned in the background art cannot obtain a high-precision material level value according to a material level reflection echo signal under the influence of technological factors such as stirring, vibration and the like; moreover, due to the measurement principle and other conditions, the blanking state of the container is difficult to identify by the conventional radar measurement system. The inventor has found through careful study that the above technical problem is caused by the fact that the material (such as a liquid material or a solid-liquid mixed state material) in the container (such as a bucket or a bin) is affected by the process factors such as stirring, vibration and the like, and the stirring rod, the stirring blade and the like of the stirring device are also in the container and continuously move, when the existing radar measurement system (such as a radar level gauge) sends out signals for measurement, the fluctuating material in the container does not reflect the signals to form echo signals, the stirring blade, the stirring rod and the like of the stirring device reflect the signals to form echo signals, and the echo signals formed by the material reflection in the container are weaker, and the echo signals formed by the stirring blade, the stirring rod and the like of the stirring device are received by the radar level gauge together, so that the radar level gauge can hardly effectively judge or screen the echo signals reflected by the materials from the echo signals, and the high-precision level value can not be obtained. It is therefore important to identify the echo signal required by the user from among the plurality of echo signals.

In addition, the moving object can generate Doppler effect, and the stationary object can not generate Doppler effect; according to the principle, the existing radar measurement system (such as doppler radar) can identify the material in a moving state based on the doppler technology, but cannot identify the static material. Based on the method, the Doppler radar can only identify the state of a material flow (namely, flowing material), and cannot distinguish whether the blanking state is blanking blockage or pipeline emptying (if the pipeline is blanking blockage, the material cannot flow out of the pipeline, if the pipeline is emptying, no material exists in the pipeline, and whether the material is in a blocking state or an emptying state, the Doppler radar cannot effectively judge whether the material is in a static state).

Therefore, the existing radar measurement system cannot obtain a high-precision material level value according to the material level reflection echo signal under the influence of technological factors such as stirring, vibration and the like; meanwhile, the existing radar measurement system is limited by the measurement principle and other conditions, and the blanking state of the container is difficult to identify.

Aiming at the technical problems, the utility model provides the following solutions:

fig. 1 is a schematic structural diagram of a composite microwave radar system with blanking and level fluctuation detection functions according to an embodiment of the present utility model, referring to fig. 1, the composite microwave radar system with blanking and level fluctuation detection functions includes a control module 110, a measurement module 120, and a signal transceiver module 130.

The signal transceiver module 130 is connected with the measurement module 120 and is used for transmitting a fixed frequency microwave signal and a continuous frequency modulation microwave signal; and, receiving the Doppler signal and the ranging echo signal and uploading to the measurement module 120; the measurement module 120 is connected with the control module 110, and is configured to generate a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal issued by the control module 110, and issue the fixed frequency microwave signal and the continuous frequency microwave signal to the signal transceiver module 130; and, receiving the Doppler signal and the ranging echo signal and uploading to the control module 110; a control module 110 for alternately generating a fixed frequency signal and a continuous frequency modulation signal; and obtaining at least one of a blanking state, a material level fluctuation state and a material level distance according to the Doppler signal and the ranging echo signal.

The measuring module at least comprises a Doppler measuring module (not shown in fig. 1), and the Doppler measuring module is connected between the control module and the signal receiving and transmitting module and is used for generating a fixed frequency microwave signal according to a fixed frequency signal issued by the control module and issuing the fixed frequency microwave signal to the signal receiving and transmitting module; and receiving Doppler signals uploaded by the signal receiving and transmitting module and uploading the Doppler signals to the control module.

As known, a fixed frequency microwave signal refers to a microwave signal of fixed frequency. Further, the continuous frequency modulated microwave signal refers to a frequency modulated continuous wave (Frequency Modulated Continuous Wave, FMCW), i.e. a continuous microwave signal with varying frequency; the continuous frequency modulation microwave signal can be modulated in various ways, such as triangular wave modulation, sawtooth wave modulation, code modulation or noise modulation.

The Doppler signal is a signal formed by reflecting a fixed frequency microwave signal through a material or an object in a moving state in the container. It will be appreciated that the frequency of the fixed frequency microwave signal is different from the frequency of the doppler signal, the frequency difference between the fixed frequency microwave signal and the doppler signal being referred to as the doppler frequency, the magnitude of the doppler frequency may be, but is not limited to, indicative of the relative velocity of movement between the composite microwave radar system and the material or object in motion in the container, etc. Optionally, the characteristic information of the doppler signal includes at least one of a level change speed of the material, a rotation speed and period of the stirring structure, a fluctuation degree of the level, or a flow state of the material. For example, when the composite microwave radar system is used to detect a blanking condition of a pipe in a container, the characteristic information of the doppler signal may include only a flow condition of material within the pipe; when the composite microwave radar system is used for detecting the fluctuation state of the material level, the characteristic information of the doppler signal may include at least one of the change speed of the material level of the material, the rotation speed of the stirring structure (for example, the stirring fan blade) and the period or the fluctuation degree of the material level.

The ranging echo signal is a signal formed by reflection of a continuous frequency modulation microwave signal by a material or an object in a container. Likewise, there is a difference frequency between the ranging echo signal and the continuous frequency modulated microwave signal that can characterize the relative distance between the composite microwave radar system and the material or object in the container, etc.; the frequency of the aforementioned difference frequency is typically low, typically kHz. Optionally, the characteristic information of the ranging echo signal at least includes a target echo signal formed by material reflection (i.e. the foregoing material level reflection echo signal), a disturbance echo signal formed by stirring structure reflection, and a disturbance echo signal formed by disturbance object reflection; the interfering objects may be, for example, container walls, pipe walls, beams in the container or in the pipe, streams, heating coils, ladders, etc. It will be appreciated that in some embodiments, the control module 110 may obtain at least one of the blanking state, the level fluctuation state and the level distance according to the doppler frequency and the difference frequency.

Optionally, the blanking state comprises a blocking state, a venting state and a flowing state, and the material level distance comprises a material distance value and/or a distance value of the stirring structure; the blanking state of the pipeline in the container is taken as an example for explanation, the blocking state can be that the pipeline for conveying materials is blocked, the emptying state can be that the pipeline is not blocked and no materials are conveyed, the flowing state can be that the pipeline is not blocked and materials are conveyed, the material distance value is the material level value, the distance value of the stirring structure can represent the space position where the stirring structure is located, and the material level fluctuation state can represent the intensity of material fluctuation in the container.

For example, the control module 110 may generate a fixed frequency signal or a continuous frequency modulation signal at intervals of a first preset time interval; the control module 110 may also generate a plurality of fixed frequency signals in a second preset time interval, generate a plurality of continuous frequency modulation signals in a third preset time interval, and so on, so as to achieve the technical effect of alternately generating the fixed frequency signals and the continuous frequency modulation signals; it can be appreciated that the first preset time interval, the second preset time interval and the third preset time interval can be adaptively adjusted according to the actual application requirement of the composite microwave radar system, which is not limited in the embodiment of the present utility model.

In summary, in the embodiment of the present utility model, the control module alternately generates the fixed frequency signal and the continuous frequency modulation signal; the measurement module generates a fixed frequency microwave signal and a continuous frequency modulation microwave signal according to the fixed frequency signal and the continuous frequency modulation signal issued by the control module and issues the fixed frequency microwave signal and the continuous frequency modulation microwave signal to the signal receiving and transmitting module; the signal receiving and transmitting module transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal; the signal receiving and transmitting module receives Doppler signals and ranging echo signals and uploads the Doppler signals and the ranging echo signals to the measuring module; the measuring module receives Doppler signals and ranging echo signals and uploads the Doppler signals and the ranging echo signals to the control module; the control module obtains at least one means of a blanking state, a material level fluctuation state and a material level distance according to the Doppler signal and the ranging echo signal, solves the problems that the existing radar measurement system cannot obtain a high-precision material level value and is difficult to identify the blanking state of a container, can obtain the precise material level distance according to the Doppler signal and the ranging echo signal, and can effectively identify the blanking state and the fluctuation material level state.

It should be noted that, in general, the container mostly includes at least one discharge port and at least one feed port, when the feed port and the discharge port are normally fed and discharged, the position of the material in the container will change at any time, and the control module 110 may at least learn the change speed and direction (i.e. rise or fall) of the position of the material in the container by using the characteristic information of the doppler signal, so as to identify the target echo signal formed by the reflection of the material from the ranging echo signal according to the change speed and direction of the position of the material, and determine the position of the material relatively accurately.

Based on this, in some embodiments, optionally, the control module 110 obtains a level fluctuation status and/or a level distance from the ranging echo signal and the level change speed of the material. At this time, the specific workflow of the composite microwave radar system is: the control module 110 alternately generates a fixed frequency signal and a continuous frequency modulation signal and transmits the signals to the measurement module 120; the measurement module 120 generates a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal, and sends the fixed frequency microwave signal and the continuous frequency microwave signal to the signal receiving and transmitting module 130; the signal transceiver module 130 transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal, and receives a Doppler signal and a ranging echo signal; the measurement module 120 receives the Doppler signal and the ranging echo signal uploaded by the signal transceiver module 130 and uploads the Doppler signal and the ranging echo signal to the control module 110; the control module 110 obtains a level fluctuation state and/or a level distance according to the ranging echo signal and the level change speed of the material. It can be appreciated that, after knowing the speed and direction of the change of the material position, the control module 110 can obtain the speed and direction of the target echo signal in the ranging echo signal, which is changed based on the previous measurement, so that even if the energy or the amplitude of the target echo signal is reduced, the target echo signal can be effectively identified from the ranging echo signal by the control module 110 even if the energy or the amplitude of the target echo signal is far smaller than echo signals (such as the disturbance echo signal and the interference echo signal) generated by reflection of other objects (such as the stirring structure and the interference object).

It should be further noted that, when structures such as a stirring fan blade are disposed in the container, and when the material rotates along with the stirring fan blade, the position of the material in the container will be continuously changed, and the rotation of the stirring fan blade is regular, the control module 110 may at least calculate the rotation speed rule, the rotation period rule, and the like of the stirring fan blade by using the feature information of the doppler signal, so as to identify the echo signal of the stirring fan blade (i.e. the disturbance echo signal formed by the reflection of the stirring structure) from the ranging echo signal according to the rotation speed rule, the rotation period rule, and the like of the stirring fan blade, determine the spatial position of the stirring fan blade, and in addition, after identifying the echo signal of the stirring fan blade from the ranging echo signal, the disturbance of the echo signal of the stirring fan blade to the target echo signal (i.e. the echo signal formed by the material in the container) is eliminated, thereby being favorable for identifying the target echo signal from the ranging echo signal, and accurately determining the position of the material.

In other embodiments, the control module 110 may optionally obtain the level fluctuation status and/or the level distance according to the ranging echo signal and the rotation speed and period of the stirring structure. At this time, the specific workflow of the composite microwave radar system is: the control module 110 alternately generates a fixed frequency signal and a continuous frequency modulation signal and transmits the signals to the measurement module 120; the measurement module 120 generates a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal, and sends the fixed frequency microwave signal and the continuous frequency microwave signal to the signal receiving and transmitting module 130; the signal transceiver module 130 transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal, and receives a Doppler signal and a ranging echo signal; the measurement module 120 receives the Doppler signal and the ranging echo signal uploaded by the signal transceiver module 130 and uploads the Doppler signal and the ranging echo signal to the control module 110; the control module 110 obtains the level fluctuation status and/or the level distance according to the ranging echo signal and the rotation speed and period of the stirring structure. It can be understood that, after knowing the rotation speed rule or the rotation period rule of the stirring blade, the control module 110 can obtain the signal position of the stirring blade echo signal in the ranging echo signal, whether the amplitude of the stirring blade echo signal is high or low, the control module 110 can keep the stirring blade echo signal (i.e. can follow the stirring blade echo signal), and identify the stirring blade echo signal from the ranging echo signal; after identifying the echo signal of the stirring fan blade, because the stirring fan blade is in a rotating state, sometimes the amplitude or energy of the echo signal of the stirring fan blade is higher than the amplitude or energy of the target echo signal, and the control module 110 can further exclude the influence of the stirring fan blade on the material position by identifying the echo signal of the stirring fan blade, so that the material position can be accurately determined.

It should be noted that in some industrial situations, the container may need to be continuously oscillated and rocked under the influence of the product process to fully mix, dissolve, react, etc., and in addition, the material position may be severely fluctuated under the influence of the structure of the stirring fan blade, etc. or the material inlet and outlet process of the container; the control module 110 may at least acquire the fluctuation degree of the material position by using the characteristic information of the doppler signal, and further identify the target echo signal formed by the material reflection from the ranging echo signal according to the fluctuation degree of the material position, so as to determine the material position more accurately.

Based on this, in still other embodiments, optionally, the control module 110 obtains a level fluctuation status and/or a level distance from the ranging echo signal and the level fluctuation level of the material. At this time, the specific working principle of the composite microwave radar system is as follows: the control module 110 alternately generates a fixed frequency signal and a continuous frequency modulation signal and transmits the signals to the measurement module 120; the measurement module 120 generates a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal, and sends the fixed frequency microwave signal and the continuous frequency microwave signal to the signal receiving and transmitting module 130; the signal transceiver module 130 transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal, and receives a Doppler signal and a ranging echo signal; the measurement module 120 receives the Doppler signal and the ranging echo signal uploaded by the signal transceiver module 130 and uploads the Doppler signal and the ranging echo signal to the control module 110; the control module 110 obtains a level fluctuation state and/or a level distance according to the ranging echo signal and the fluctuation degree of the level of the material. It can be understood that after knowing the fluctuation degree of the material position, the control module 110 can obtain the fluctuation range of the target echo signal in the ranging echo signal on the basis of the previous measurement, and find the target echo signal measured in this fluctuation range, so that even if the energy or amplitude of the target echo signal becomes smaller or even far smaller than the echo signal (i.e. the disturbance echo signal and the interference echo signal) generated by the stirring structure and the reflection of the interfering object, the control module 110 can keep up with the target echo signal (i.e. the following of the target echo signal can be performed), and effectively identify the target echo signal from the ranging echo signal.

It should be noted that, since a moving object generates a doppler effect, and a stationary object does not generate a doppler effect, only a flow state can be recognized by a doppler signal, and a blockage state and a vent state cannot be distinguished. However, when the pipeline is blocked, the pipeline is filled with materials, but the materials cannot flow out of the pipeline, and at this time, the ranging echo signal contains characteristic information of the blocked materials in the pipeline; when the pipeline is empty, no material exists in the pipeline, and the ranging echo signal does not contain characteristic information of the blocked material in the pipeline; therefore, when the material is in the non-flowing state (namely the blocking state and the emptying state) based on the Doppler signal, the blocking state and the emptying state can be effectively distinguished by combining the ranging echo signal, and the control module 110 can effectively judge whether the pipeline blanking is in the blocking state or the emptying state.

In view of this, in yet other embodiments, the control module 110 optionally obtains the blanking condition based on the ranging echo signal and the flow condition of the material. At this time, the specific working principle of the composite microwave radar system is as follows: the control module 110 alternately generates a fixed frequency signal and a continuous frequency modulation signal and transmits the signals to the measurement module 120; the measurement module 120 generates a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal, and sends the fixed frequency microwave signal and the continuous frequency microwave signal to the signal receiving and transmitting module 130; the signal transceiver module 130 transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal, and receives a Doppler signal and a ranging echo signal; the measurement module 120 receives the Doppler signal and the ranging echo signal uploaded by the signal transceiver module 130 and uploads the Doppler signal and the ranging echo signal to the control module 110; after knowing that the material is in a non-flowing state based on the doppler signal, the control module 110 obtains a blanking state according to the ranging echo signal and the obtained flowing state of the material.

On the basis of the above embodiment, fig. 2 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation detection functions according to the embodiment of the present utility model, and fig. 3 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation detection functions according to the embodiment of the present utility model. Referring to fig. 2 and 3, optionally, the measurement module 120 further includes a ranging module 122; the ranging module 122 is connected between the control module 110 and the signal transceiver module 130, and is configured to generate a continuous frequency modulation microwave signal according to the continuous frequency modulation signal issued by the control module 110, and issue the continuous frequency modulation microwave signal to the signal transceiver module 130; and, the ranging echo signal uploaded by the receiving signal transceiver module 130 is uploaded to the control module 110.

Optionally, the signal transceiver module 130 includes a common antenna structure 131, and the common antenna structure 131 is shared by the doppler measurement module 121 and the ranging module 122; alternatively, the signal transceiver module 130 includes a first antenna structure 132 and a second antenna structure 133; the first antenna structure 132 is connected to the doppler measurement module 121, and is configured to transmit a fixed frequency microwave signal, receive a doppler signal, and upload the doppler signal to the doppler measurement module 121; the second antenna structure 133 is connected to the ranging module 122, and is configured to transmit the continuous frequency modulation microwave signal, receive the ranging echo signal, and upload the ranging echo signal to the ranging module 122.

The common antenna structure 131, the first antenna structure 132, and the second antenna structure 133 may be antennas that are integrated with each other, or may be antennas that are separated from each other; the antenna structure may be, but is not limited to, a dipole antenna, or a microstrip antenna.

Illustratively, with continued reference to fig. 2, assuming that the control module 110 generates a fixed frequency signal and then generates a continuous frequency modulated signal, the workflow of the composite microwave radar system may be specifically as follows:

the control module 110 generates a fixed frequency signal; the Doppler measurement module 121 generates a fixed frequency microwave signal according to the fixed frequency signal issued by the control module 110 and issues the fixed frequency microwave signal to the common antenna structure 131; the common antenna structure 131 emits a fixed frequency microwave signal; the common antenna structure 131 receives the doppler signal and uploads the doppler signal to the doppler measurement module 121; the Doppler measurement module 121 receives Doppler signals uploaded by the common antenna structure 131 and uploads the Doppler signals to the control module 110; the control module 110 generates a continuous frequency modulation signal; the ranging module 122 generates continuous frequency modulation microwave signals according to the continuous frequency modulation signals issued by the control module 110 and issues the continuous frequency modulation microwave signals to the common antenna structure 131; the common antenna structure 131 transmits continuous frequency modulated microwave signals; the common antenna structure 131 receives the ranging echo signals and uploads them to the ranging module 122; the ranging module 122 receives the ranging echo signals uploaded by the common antenna structure 131 and uploads the ranging echo signals to the control module 110; the control module 110 obtains at least one of a blanking state, a level fluctuation state, and a level distance from the Doppler signal and the ranging echo signal.

Illustratively, with continued reference to fig. 3, assuming that the control module 110 generates a continuous frequency modulated signal and then a fixed frequency signal, the workflow of the composite microwave radar system may be specified as follows:

the control module 110 generates a continuous frequency modulation signal; the ranging module 122 generates continuous frequency modulation microwave signals according to the continuous frequency modulation signals issued by the control module 110 and issues the continuous frequency modulation microwave signals to the second antenna structure 133; the second antenna structure 133 emits a continuous frequency modulated microwave signal; the second antenna structure 133 receives the ranging echo signal and uploads to the ranging module 122; the ranging module 122 receives the ranging echo signal uploaded by the second antenna structure 133 and uploads the ranging echo signal to the control module 110; the control module 110 generates a fixed frequency signal; the Doppler measurement module 121 generates a fixed frequency microwave signal according to the fixed frequency signal issued by the control module 110 and issues the fixed frequency microwave signal to the first antenna structure 132; the first antenna structure 132 emits a fixed frequency microwave signal; the first antenna structure 132 receives the Doppler signal and uploads the Doppler signal to the Doppler measurement module 121; the Doppler measurement module 121 receives Doppler signals uploaded by the first antenna structure 132 and uploads the Doppler signals to the control module 110; the control module 110 obtains at least one of a blanking state, a level fluctuation state, and a level distance from the Doppler signal and the ranging echo signal.

In summary, the embodiment of the utility model can overcome the defects that the existing radar measurement system cannot obtain a high-precision material level value and is difficult to identify the blanking state of a container, can obtain a precise material level distance according to the characteristic information of Doppler signals and ranging echo signals, and can effectively identify the blanking state and the material level fluctuation state. In addition, compared with a signal transceiver module comprising a first antenna structure and a second antenna structure, when the signal transceiver module adopts a shared antenna structure, the method and the device can further simplify the process steps of the composite microwave radar system, and are beneficial to reducing the hardware cost of the composite microwave radar system.

On the basis of the above embodiment, fig. 4 is a schematic structural diagram of another composite microwave radar system with blanking and level fluctuation state detection functions according to an embodiment of the present utility model. Referring to fig. 4, the control module 110 optionally includes a micro control unit 110, an AD collector 113, an amplifier 112, and a microwave unit 114; the microwave unit 114 is respectively connected with the measurement module 120, the micro control unit 111 and the amplifier 112, and is used for alternately generating a fixed frequency signal and a continuous frequency modulation signal according to control parameters issued by the micro control unit 111 and issuing the fixed frequency signal and the continuous frequency modulation signal to the measurement module 120; and, receiving the Doppler signal and the ranging echo signal uploaded by the measurement module 120, generating a first mixing signal according to the Doppler signal and generating a second mixing signal according to the ranging echo signal, and transmitting the first mixing signal and the second mixing signal to the amplifier 112; the micro control unit 111 is connected to the amplifier 112 through the AD collector 113, and is configured to obtain, according to the first mixing signal and the second mixing signal after being amplified by the amplifier 112 and subjected to signal conversion by the AD collector 113, characteristic information of the doppler signal and the ranging echo signal, and further obtain at least one of a blanking state, a level fluctuation state, and a level distance.

Optionally, the microwave unit 114 includes a mixer 114a and a local oscillator circuit 114b; a local oscillation circuit 114b connected to the mixer 114a for generating a local oscillation signal and transmitting the local oscillation signal to the mixer 114a; the mixer 114a is connected between the amplifier 112 and the measurement module 120, and is used for receiving the Doppler signal and the ranging echo signal uploaded by the measurement module 120; and, after the local oscillation signal and the Doppler signal are mixed to obtain a first mixed signal, and the local oscillation signal and the ranging echo signal are mixed to obtain a second mixed signal, the first mixed signal and the second mixed signal are transmitted to the amplifier 112.

Optionally, the method further comprises:

the display module 140 is connected with the control module 110 and is at least used for displaying one of a blanking state, a material level fluctuation state and a material level distance; the power supply module 150 is connected to the control module 110, and is used for accessing external power supply and converting the external power supply into multi-stage working voltage so as to maintain the normal operation of the composite microwave radar system.

Wherein, the amplifier 112 is configured to amplify the first mixed signal and the second mixed signal; the AD collector 113 is configured to perform signal conversion on the amplified first mixed signal and the amplified second mixed signal, and upload the signals to the micro control unit 111; the micro control unit 111 may be a system on a chip, a single chip microcomputer, a DSP processor, etc.; the AD collector 113 may employ any AD conversion circuit; amplifier 112 may be any signal amplifying circuit; the control parameters issued by the micro control unit 111 may include at least signal frequency information, signal amplitude information and signal width information; the external power supply may be mains; the multi-stage operating voltage is used for guaranteeing steady-state operation of the micro control unit 111, the AD collector 113, the amplifier 112, the microwave unit 114 and the like, so as to maintain normal operation of the whole composite microwave radar system, and the multi-stage operating voltage can comprise voltage levels of 3.3V, 5V, 12V, 15V or 24V and the like; the display module 140 may be a CRT display, an LCD display, an LED display, or the like.

With continued reference to fig. 4, the workflow of the composite microwave radar system may be embodied as follows:

the power supply module 150 accesses external power supply and converts the external power supply into a multi-stage working voltage to maintain the normal operation of the composite microwave radar system; the micro control unit 111 issues control parameters to the microwave unit 114; the microwave unit 114 alternately generates a fixed frequency signal and a continuous frequency modulation signal according to the control parameters and transmits the signals to the measurement module 120; the measurement module 120 generates a fixed frequency microwave signal and a continuous frequency microwave signal according to the fixed frequency signal and the continuous frequency signal, and sends the fixed frequency microwave signal and the continuous frequency microwave signal to the signal receiving and transmitting module 130; the signal transceiver module 130 transmits a fixed frequency microwave signal and a continuous frequency modulation microwave signal; the signal transceiver module 130 receives the doppler signal and the ranging echo signal and uploads the signals to the measurement module 120; the local oscillation circuit 114b generates a local oscillation signal and transmits the local oscillation signal to the mixer 114a, and the measurement module 120 receives the Doppler signal and the ranging echo signal and uploads the Doppler signal and the ranging echo signal to the mixer 114a; the mixer 114a mixes the local oscillation signal and the Doppler signal to obtain a first mixed signal, mixes the local oscillation signal and the ranging echo signal to obtain a second mixed signal, and then transmits the first mixed signal and the second mixed signal to the amplifier 112; the amplifier 112 amplifies the first mixed signal and the second mixed signal; the AD collector 113 performs signal conversion on the amplified first mixed signal and second mixed signal, and then uploads the signals to the micro control unit 111; the micro control unit 111 obtains characteristic information of Doppler signals and ranging echo signals according to the first mixed signals and the second mixed signals which are amplified by the amplifier 112 and subjected to signal conversion by the AD collector 113, and further obtains a blanking state, a material level fluctuation state and/or a material level distance; the display module 140 displays a blanking state, a level fluctuation state, and/or a level distance.

Illustratively, the AD collector 113 may sample the first mixed signal to generate a first AD sampled signal, and specifically, the AD collector 113 may collect the first mixed signal and convert a signal type of the first mixed signal from an analog signal to a discrete digital signal, where the discrete digital signal is the first AD sampled signal; similarly, the AD collector 113 may further sample the second mixed signal to generate a second AD sampled signal, and specifically, the AD collector 113 may collect the second mixed signal and convert the signal type of the second mixed signal from an analog signal to a discrete digital signal, where the discrete digital signal is the second AD sampled signal.

It is known that the local oscillator signal may be a fixed frequency signal or a continuous frequency modulated signal, and the frequency of the local oscillator signal may be linearly varied over time, i.e., chirped. It will be appreciated that there are differences in frequency between the local oscillator signal and the doppler signal and between the local oscillator signal and the ranging echo signal, and based on this, the first mixed signal is a signal that can characterize the frequency difference between the local oscillator signal and the doppler signal, and the second mixed signal is a signal that can characterize the frequency difference between the local oscillator signal and the ranging echo signal. In general, the frequency of the mixed signal is lower, so that the sampling rate requirements of the first mixed signal and the second mixed signal on the AD collector are lower, and the hardware cost of the composite microwave radar system is reduced.

In some embodiments, the micro control unit 111 obtains the characteristic information of the doppler signal and the ranging echo signal according to the first mixing signal and the second mixing signal amplified by the amplifier 112 and subjected to signal conversion by the AD collector 113, so as to obtain at least one of the blanking state, the level fluctuation state and the level distance, which may include: the micro control unit 111 performs one-dimensional fourier transform operation on the first mixed signal and the second mixed signal, which are amplified by the amplifier 112 and subjected to signal conversion by the AD collector 113, so as to correspondingly obtain characteristic information of the doppler signal and the ranging echo signal, thereby obtaining at least one of a blanking state, a material level fluctuation state and a material level distance.

Further, in other embodiments, the microwave unit 114 may alternatively generate at least 8 continuous frequency modulation signals at equal intervals, with the total frequency modulation time of the continuous frequency modulation signals being greater than 10ms; the micro control unit 111 is further configured to perform two-dimensional fourier transform on at least 8 second mixed signals amplified by the amplifier 112 and subjected to signal conversion by the AD collector 113, so as to obtain a plurality of velocity echo curves; the micro control unit 111 obtains the level fluctuation state and/or the level distance according to the characteristic information of the plurality of velocity echo curves and the Doppler signals.

Specifically, when the microwave unit 114 sequentially generates a plurality of continuous frequency modulation signals, the microwave unit 114 may generate a plurality of continuous frequency modulation signals at equal intervals, and the total frequency modulation duration of the plurality of continuous frequency modulation signals is preferably 20ms; the plurality of continuous frequency modulation signals sequentially enter the ranging module 122, the ranging module 122 sequentially transmits the plurality of continuous frequency modulation microwave signals into the container or the pipeline through the signal receiving and transmitting module 130, the plurality of continuous frequency modulation microwave signals sequentially reflect through materials, stirring structures and the like to form a plurality of ranging echo signals and are sequentially received by the ranging module 122, the mixer 114a mixes each ranging echo signal and the continuous frequency modulation signals corresponding to each ranging echo signal to sequentially obtain a plurality of second mixed signals, the micro-control unit 111 performs two-dimensional Fourier transform on the plurality of second mixed signals subjected to amplification and AD sampling processing to obtain echo curves (namely a plurality of speed echo curves), and accordingly speed information of each ranging echo signal can be obtained. Then, the micro control unit 111 may select an echo curve at a corresponding speed according to the speed of the level change obtained by the characteristic information of the doppler signal, the speed law of rotation of the stirring blade, and the like, so as to obtain a ranging echo signal corresponding to the speed, and finally, select and identify a target echo signal and the stirring blade echo signal from the corresponding ranging echo signals, so as to confirm the position of the material and the position of the stirring blade, and obtain a precise level distance and a level fluctuation state.

Illustratively, the two-dimensional fourier transform process may specifically be: the plurality of continuous frequency modulation signals sequentially enter the ranging module 122, the ranging module 122 sequentially transmits the plurality of continuous frequency modulation microwave signals into the container or the pipeline through the signal receiving and transmitting module 130, the plurality of continuous frequency modulation microwave signals sequentially form a plurality of ranging echo signals through reflection of materials, stirring structures and the like and are sequentially received by the ranging module 122, the mixer 114 sequentially mixes each ranging echo signal and the continuous frequency modulation signals corresponding to each ranging echo signal to obtain a plurality of second mixed signals, the plurality of second mixed signals are sequentially subjected to one-dimensional Fourier transform in the first direction to obtain a plurality of echo curves, and then the obtained plurality of echo curves are subjected to one-dimensional Fourier transform in the second direction to obtain a plurality of echo curves at different speeds, so that speed information of each ranging echo signal is obtained.

In summary, the embodiment of the utility model can overcome the defects that the existing radar measurement system cannot obtain a high-precision material level value and is difficult to identify the blanking state of a container, can obtain a precise material level distance according to the characteristic information of Doppler signals and ranging echo signals, and can effectively identify the blanking state and the material level fluctuation state.

Note that the above is only a preferred embodiment of the present utility model and the technical principle applied. It will be understood by those skilled in the art that the present utility model is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the utility model. Therefore, while the utility model has been described in connection with the above embodiments, the utility model is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the utility model, which is set forth in the following claims.

Claims

1. The composite microwave radar system with the blanking and material level fluctuation state detection functions is characterized by comprising a control module, a measurement module and a signal receiving and transmitting module;

wherein the measurement module at least comprises a Doppler measurement module;

the Doppler measurement module is connected between the control module and the signal receiving and transmitting module and is used for generating the fixed frequency microwave signal according to the fixed frequency signal issued by the control module and issuing the fixed frequency microwave signal to the signal receiving and transmitting module; and receiving the Doppler signal uploaded by the signal receiving and transmitting module and uploading the Doppler signal to the control module.

2. The composite microwave radar system of claim 1, wherein the blanking condition comprises a plugged condition, a vented condition, and a flow condition;

3. The composite microwave radar system according to claim 1, wherein the characteristic information of the doppler signal includes at least one of a level change speed of the material, a rotation speed and period of the stirring structure, a fluctuation degree of the level, or a flow state of the material;

4. The composite microwave radar system of claim 1, wherein the measurement module further comprises a ranging module;

5. The composite microwave radar system of claim 4, wherein the signal transceiver module includes a common antenna structure that is common to the doppler measurement module and the ranging module;

6. The composite microwave radar system of claim 1, wherein the control module comprises a micro-control unit, an AD collector, an amplifier, and a microwave unit;

7. The composite microwave radar system of claim 6, wherein the microwave unit includes a mixer and a local oscillator circuit;

8. The composite microwave radar system of claim 6, wherein the microwave unit generates at least 8 of the continuous frequency modulated signals at equal intervals, the continuous frequency modulated signals having a total time period of frequency modulation greater than 10ms.

9. The composite microwave radar system of claim 8, wherein the micro control unit is further configured to perform two-dimensional fourier transform on at least 8 of the second mixed signals amplified by the amplifier and subjected to signal conversion by the AD collector, so as to obtain a plurality of velocity echo curves.

10. The composite microwave radar system according to claim 9, wherein the micro control unit obtains the level fluctuation status and/or the level distance from the plurality of velocity echo curves and the characteristic information of the doppler signal.

11. A composite microwave radar system according to claim 3, wherein the control module obtains the level fluctuation status and/or the level distance from the ranging echo signal and the rotational speed and period of the stirring structure.

12. A composite microwave radar system according to claim 3, characterized in that the control module obtains the level fluctuation status and/or the level distance from the ranging echo signal and the level fluctuation level of the material.

13. A composite microwave radar system according to claim 3, wherein the control module obtains the blanking condition from the ranging echo signal and a flow condition of the material.

14. The composite microwave radar system of claim 1, further comprising: