CN212848829U - Harmonic suppression antenna - Google Patents

Abstract

The utility model provides a harmonic restraines the antenna, the harmonic restraines the antenna and is suitable for a signal processing module, signal processing module has an excitation signal source. The harmonic suppression antenna comprises a dual coupling stage sub-antenna and a harmonic suppression unit, wherein the dual coupling stage sub-antenna comprises a first antenna element and a second antenna element, the first antenna element is adjacently and spacedly arranged on the second antenna element, and the first antenna element and the second antenna element are homologously fed, so that the first antenna element is dually coupled with the second antenna element.

Description

Harmonic suppression antenna

Technical Field

The utility model relates to a microwave detection field especially relates to a harmonic suppression antenna.

Background

With the development of the internet of things technology and 5G high-speed communication, the requirements of artificial intelligence, smart home and intelligent security technology on the accuracy of environment detection, especially on the detection of the action characteristics of human existence, movement and micromotion, are higher and higher. Only if a stable enough detection result is obtained, accurate judgment basis can be provided for the intelligent terminal equipment. The microwave detection technology based on the Doppler effect principle is used as a person and an object, and an important pivot connected between the object and the object has unique advantages in behavior detection and existence detection technologies, can detect characteristic information of the object under the condition of not invading the privacy of the person, and therefore has wide application prospects.

Microwave detection antennas are used as basic devices in the field of microwave detection, and can transmit and receive microwave signals in a specific frequency band, and the definition and permission of different frequency bands can regulate the use frequency bands of radios and reduce the probability of mutual interference between radios in different frequency bands, however, the problem of mutual interference between radios in adjacent or same frequency bands is becoming more serious. The precision of the signals transmitted and received by the microwave detection antenna can directly influence the detection precision, and the radio technology is simultaneously used as a pivot for information transmission in the communication field, and the anti-interference capability of the radio technology is concerned with economy and national defense safety.

A microwave detector based on the doppler effect principle, which transmits and receives microwave signals of a specific frequency band and obtains doppler intermediate frequency signals corresponding to a living body, may be used to detect the motion of a living body, such as a human or an animal, using the doppler effect principle. The main factors influencing the detection accuracy of the microwave detector are harmonic signals generated and received by the microwave antenna and detection dead zones generated by the antenna self factors. Firstly, the feedback of the harmonic signals generated by the microwave detector to the human body activity is incomplete and accurate, and the completeness and the accuracy of the feedback of the current microwave detector to the human body activity are further limited along with the increasing complexity of the electromagnetic environment. On the other hand, the antenna structure of the microwave detector is mainly divided into a microwave detection module with a columnar radiation source structure and a microwave detection module with a flat radiation source structure, and no matter which structure of the antenna structure has a detection dead zone.

SUMMERY OF THE UTILITY MODEL

The utility model has the advantages of a major advantage of providing a harmonic restraines the antenna, wherein the harmonic restraines the antenna and has reduced the harmonic signal of sending and receiving, is favorable to improving and has a microwave detection device's of harmonic restraines the antenna detection accuracy.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the harmonic suppression antenna has a relatively high radiation gain by using dual coupling mode, and can avoid forming a detection dead zone.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the microwave detection device is based on the harmonic suppression antenna transmission and the received microwave signal obtain an undulation signal, wherein the undulation signal corresponds to the motion characteristic of the object in the environment, so as by the moving object in the microwave detection device detection environment.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the microwave detection device obtains the fluctuation signal corresponds to the activity characteristic of a living body (animal or human) in the environment, which is advantageous for the microwave detection device to detect the activity characteristic of the living body in the environment.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the harmonic suppression antenna reduces electromagnetic radiation in the environment to the interference of the fluctuation signal, which is favorable for improvement the anti-interference microwave detection module is right the accuracy of detection of the action of the object in the detection space.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the harmonic suppression antenna is advantageous by reducing the harmonic of the transmitted and received microwave signal to obtain a micro motion characteristic corresponding to the living body, such as moving, micro-moving, breathing and heartbeat.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the harmonic suppression antenna includes a harmonic suppression unit and a dipole coupling dipole antenna, wherein the harmonic suppression network is electrically connected to the dipole coupling dipole antenna, whereby the harmonic suppression network reduces electromagnetic radiation in the environment to be right the interference of the fluctuation signal, so as to be favorable to improving the accuracy of the feedback of the fluctuation signal to the human body activity.

Another advantage of the present invention is to provide a harmonic suppression antenna, wherein the harmonic suppression antenna allows the signal between specific frequency intervals to pass through to reduce the noise signal in the harmonic signal and the received environment that are sent to the outside, which is favorable for improving the accuracy of detection by the microwave detection device.

The other advantages and features of the invention will be fully apparent from the following detailed description and realized by means of the instruments and combinations particularly pointed out in the appended claims.

According to the utility model discloses an aspect can realize aforementioned purpose and other purposes and advantage the utility model discloses a harmonic restraines antenna, include:

a dual-coupling-pole antenna, wherein the dual-coupling-pole antenna comprises a first antenna element and a second antenna element, the first antenna element being adjacently and spaced apart from the second antenna element, the first antenna element and the second antenna element being isostatically fed such that the first antenna element is dual-coupled to the second antenna element; and

a harmonic suppression unit, wherein the harmonic suppression unit comprises at least one equivalent capacitor and at least one equivalent inductor, the equivalent capacitor and the equivalent inductor are electrically connected to the first antenna element of the dual-coupled-pole sub-antenna, so that the harmonic suppression unit electrically connects the first antenna element to a feed of an excitation signal source, and the second antenna element is electrically connected to a ground of the excitation signal source.

According to the present invention, the harmonic suppression unit comprises an equivalent capacitor and an equivalent inductor, and the equivalent capacitor and the equivalent inductor form a frequency-selective network having selective characteristics for an electrical signal in a frequency range including the frequency of the excitation signal.

According to an embodiment of the present invention, the first antenna unit is grounded through at least one of the equivalent inductances of the harmonic suppression unit.

According to the utility model discloses an embodiment, wherein with at least one of the equivalent inductance of first antenna element ground connection is set up as the microstrip line.

According to an embodiment of the present invention, at least one of the equivalent inductances connecting the first antenna element to ground is provided as a resistive element.

According to an embodiment of the present invention, the equivalent capacitor further comprises a first capacitor unit, a second capacitor unit, a third capacitor unit and a fourth capacitor unit, the equivalent inductor further comprises a first inductor unit, a second inductor unit and a third inductor unit, wherein the first capacitance element and the first inductance element are electrically connected to the first antenna element of the dual-coupled pole sub-antenna, and the first antenna element is grounded through the first inductance element, the second inductance element and the third inductance element are connected in series with the first inductance element, the second capacitor unit, the third capacitor unit and the fourth capacitor unit of the equivalent capacitor are connected in parallel with the first inductor unit, and the second, third and fourth capacitive units are grounded.

According to an embodiment of the present invention, wherein the second capacitor unit is connected in series with the first capacitor unit and passes through the second capacitor unit is grounded, the third capacitor unit is connected in series with the first capacitor unit and the second inductor unit and passes through the third capacitor unit is grounded, the fourth capacitor unit is connected in series with the first capacitor unit, the second inductor unit and the third inductor unit and passes through the fourth capacitor unit is grounded.

According to an embodiment of the present invention, wherein the first capacitor unit of the equivalent capacitor of the harmonic suppression unit is implemented as a capacitor element, and the second capacitor unit, the third capacitor unit and the fourth capacitor unit of the equivalent capacitor are implemented as microstrip lines.

According to an embodiment of the present invention, wherein the first capacitor unit, the third capacitor unit and the fourth capacitor unit of the equivalent capacitance of the harmonic suppression unit are implemented as a capacitor element, and the second capacitor unit of the equivalent capacitance is implemented as a microstrip line.

According to the utility model discloses an embodiment, wherein the dual coupling polar antenna the first antenna element with the second antenna element is set up by axial symmetry, the second antenna element with the line length of interval distance between the first antenna element is less than or equal to lambda/16, wherein lambda is the wavelength parameter of corresponding feed signal frequency.

According to an embodiment of the present invention, the dual-coupled dipole antenna further includes a circuit substrate, the first antenna element and the second antenna element are fixed to the circuit substrate, and the harmonic suppression unit is disposed on the circuit substrate, and the second antenna element is grounded on the circuit substrate.

According to an embodiment of the present invention, wherein the harmonic suppression antenna further includes an electromagnetic reflection unit, which is disposed on the circuit substrate, the electromagnetic reflection unit and the harmonic suppression unit are disposed back to back on the circuit substrate.

According to an embodiment of the present invention, wherein the harmonic suppression antenna further includes an antenna fixing base, wherein the first antenna element and the second antenna element are fixed to the circuit substrate by the antenna fixing base.

According to an embodiment of the present invention, the first antenna unit further includes a first feeding end and a first mounting end extending integrally from the first feeding end, wherein the first feeding end is installed on the circuit substrate through the first mounting end, and the end portion of the first mounting end is electrically connected to the harmonic suppression unit, the second antenna unit further includes a second feeding end and a second mounting end extending integrally from the second feeding end, wherein the second mounting end is installed on the circuit substrate.

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the appended claims.

Drawings

Fig. 1 is a schematic diagram of a microwave detecting device according to a first preferred embodiment of the present invention.

Fig. 2 is a schematic diagram of an analog circuit of a harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Fig. 3 is a schematic diagram of the overall structure of the harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Fig. 4A and 4B are schematic structural diagrams of the harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Fig. 5 is a schematic diagram of a harmonic suppression unit of the harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Fig. 6 is a sectional view of the harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Fig. 7 is a schematic diagram of another alternative implementation of a harmonic suppression unit of the harmonic suppression antenna of the microwave detection apparatus according to the above preferred embodiment of the present invention.

Fig. 8 is a schematic diagram of an analog circuit of another harmonic suppression antenna of the microwave detecting device according to the above preferred embodiment of the present invention.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in a generic and descriptive sense only and not for purposes of limitation, as the terms are used in the description to indicate that the referenced device or element must have the specified orientation, be constructed and operated in the specified orientation, and not for the purpose of limitation.

It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.

Referring to the drawings of the present invention to fig. 1 to 6, a microwave detecting device according to a first preferred embodiment of the present invention will be explained in the following description. The microwave detection device comprises a signal processing module 10 and a harmonic suppression antenna 20 electrically connected with the signal processing module 10, wherein the signal processing module 10 sends an excitation signal of microwaves to the harmonic suppression antenna 20, and the harmonic suppression antenna 20 sends out a microwave detection signal of a specific frequency under the excitation of the signal processing module 10. The microwave suppression antenna 20 sends the microwave detection signal under the excitation of the signal processing module 10, and receives an echo signal of the microwave detection signal reflected by a detected object in an environment, wherein the echo signal received by the harmonic suppression antenna 20 is transmitted to the signal processing module 10, and the signal processing module 10 obtains a doppler signal corresponding to the detected object based on a doppler effect principle according to a difference between the microwave detection signal and the echo signal sent by the harmonic suppression antenna. It will be understood by those skilled in the art that the doppler signal obtained by the signal processing module 10 can be obtained based on the frequency difference/phase difference between the microwave detection signal and the echo signal, and then the frequency of the doppler signal corresponds to the velocity of the detected object in the direction of the line connecting the harmonic suppression antenna 20. The signal processing module 10 obtains a fluctuation signal corresponding to the movement of the detected object based on the trend processing of the doppler signal, that is, the microwave detecting device obtains the fluctuation signal by trend processing of the doppler signal, so that the characteristics of each fluctuation in the fluctuation signal can be used to characterize the action characteristics of the corresponding action of the detected object.

Preferably, in this preferred embodiment of the present invention, the signal processing module 10 of the microwave detecting device trends the doppler signal according to the change of the frequency of the doppler signal with time to obtain the fluctuation signal, for example, trend the doppler signal in a filtering manner with an integral characteristic to obtain the fluctuation signal corresponding to the change of the frequency of the doppler signal with time, and selectively output the fluctuation of a specific frequency in the wave signal, thereby the corresponding relationship between the frequency of the fluctuation signal and the frequency of the corresponding action represents the activity or the motion characteristic of the living body such as human or animal. For example, in the preferred embodiment of the present invention, when the frequency of the fluctuation signal obtained after the low-pass filtering process by the signal processing module 10 of the microwave detection device is lower than 25Hz, the fluctuation signal of 3Hz or above in the fluctuation signal corresponds to the micro motion of the human body, such as walking, swinging arm, etc.; when the fluctuation signal with the frequency of 1Hz to 3Hz obtained after the low-pass filtering processing of the signal processing module 10 corresponds to the heartbeat action of the human body; the fluctuation signal of the fluctuation signal at 1Hz or below obtained after the low-pass filtering processing by the signal processing module 10 corresponds to the breathing action of the human body. In other words, in this preferred embodiment of the invention, the signal processing module 10 of the microwave detection device characteristically processes the doppler signal according to the activity characteristics of the human body to obtain the fluctuation signal corresponding to human specific activity, whereby the fluctuation signal represents human activity.

It is worth mentioning that in the preferred embodiment of the present invention, the signal processing module 10 is implemented in the form of discrete components, wherein the signal processing module 10 includes an oscillation circuit 11, a mixing detection unit 12, and a signal conversion unit 13, wherein the oscillation circuit 11 is electrically coupled with the mixing detection unit 12 and the harmonic suppression antenna 20, respectively, and is configured to generate an excitation signal of a microwave signal, and the oscillation circuit 11 provides the excitation signal to the mixing detection unit 12 and the harmonic suppression antenna 20. The harmonic suppression antenna 20 emits a microwave detection signal having the same frequency as the excitation signal under the excitation action of the excitation signal. The mixer-detector unit 12 is electrically connected to the harmonic rejection antenna 20, and the doppler signal is obtained by the mixer-detector unit 12 according to the doppler effect principle and the signal transmitted and received by the harmonic rejection antenna. The signal conversion unit 13 is electrically connected to the mixed wave detection unit 12, wherein the signal conversion unit 13 is configured to process the doppler signal based on a trend of a change in frequency of the doppler signal with time to obtain the fluctuation signal corresponding to the object to be detected, whereby a fluctuation frequency in the fluctuation signal corresponds to a frequency of an action of the object in the detection space.

The signal processing module 10 further comprises an amplifying unit 14, wherein the amplifying unit 14 is electrically connected between the mixing detection unit 12 and the signal converting unit 13, and the amplifying unit 14 is adapted to amplify the doppler signal obtained by the mixing detection unit 12, so as to facilitate the processing of the signal converting unit 13.

As shown in fig. 2 and 3, the harmonic suppression antenna 20 includes a harmonic suppression unit 21 and a pair of dipole antennas 22, wherein the harmonic suppression unit 21 is electrically connected to the dipole antennas 22, and the dipole antennas 22 are electrically connected to the signal processing module 10 through the harmonic suppression unit 21. The excitation signal of the signal processing module 10 is transmitted to the dual-coupling pole antenna 22 through the harmonic suppression unit 21, so as to excite the dual-coupling pole antenna 22 to emit a wireless detection signal having the same frequency as the excitation signal. The dual-coupled pole antenna 22 is further configured to receive microwave signals in an environment, wherein the microwave signals received by the dual-coupled pole antenna 22 are filtered by the harmonic suppression unit, so that the harmonic suppression unit 21 filters noise signals in the microwave signals, and the noise signals are prevented from affecting the detection structure of the microwave detection apparatus. The harmonic suppression unit 21 of the harmonic suppression antenna 20 selectively receives the echo signal through the dual-coupled pole sub-antenna 22 in a frequency-selective manner, so that the mixer-detector unit 12 of the signal processing module 10 performs mixer-detection on the excitation signal and the echo signal to obtain a corresponding doppler signal.

As shown in fig. 2, the dual-coupled pole sub-antenna 22 includes a first antenna element 221 and a second antenna element 222, wherein the first antenna element 221 is electrically connected to the harmonic suppression unit 21, the second antenna element 222 is fed in a homologous manner with the first antenna element 221, and the second antenna element 222 is grounded, the second antenna element 222 is adjacently disposed to the first antenna element 221, and the first antenna element 221 and the second antenna element 222 are disposed at intervals from each other. Therefore, when the first antenna element 221 and the second antenna element 222 of the dual-coupling-pole sub-antenna 22 are fed by the same source, the first antenna element 221 and the second antenna element 222 of the dual-coupling-pole sub-antenna 22 form a dual coupling manner.

The harmonic suppression unit 21 includes at least one equivalent capacitor 211 and at least one equivalent inductor 212, wherein the equivalent capacitor 211 is electrically connected to the first antenna unit 221 of the dual-coupled dipole antenna 22 and the mixer-detector unit 12 of the signal processing module 10. The equivalent inductor 212 is electrically connected to the first antenna element 221 of the dual-coupled-pole sub-antenna 22, and the first antenna element 221 is grounded through the equivalent inductor 212. The equivalent capacitor 211 and the equivalent inductor 212 of the harmonic suppression unit 21 form a frequency-selective network, wherein the frequency-selective network is a circuit that selectively allows an electrical signal in a specific frequency interval to pass through. The specific frequency interval is a frequency interval containing the excitation signal, for example, the electric signal of the specific frequency interval is selectively allowed to pass through by the high impedance characteristic of the electric signal of all or part of the frequency interval deviating from the frequency of the excitation signal, or the electric signal of the specific frequency interval is selectively allowed to pass through by the low impedance attenuation to the ground of the electric signal of all or part of the frequency interval deviating from the frequency of the excitation signal, so that the selection characteristic of the frequency selection network on the electric signal of the specific frequency interval containing the frequency of the excitation signal is formed. Accordingly, the frequency-selective network formed by the harmonic suppression unit 21 can prevent other signals except the specific frequency from passing through, so as to prevent noise signals in other frequency bands from being received.

In short, the present invention discloses that the harmonic suppression unit 21 can be implemented as a resonant tank, or at least a filter, and the harmonic suppression unit 21 selectively allows the electric signal in the specific frequency interval to pass through the frequency selection network, so as to selectively transmit the echo signal to the mixing detection unit 12 from the dual-coupled dipole antenna 22 based on the selection characteristic of the frequency selection network for the electric signal in the specific frequency interval.

It should be mentioned that, in the preferred embodiment of the present invention, the equivalent capacitor 211 and the equivalent inductor 212 of the harmonic suppression unit 21 are components or microstrip lines respectively having a capacitance characteristic and an inductance characteristic under a high-frequency current corresponding to the frequency of the excitation signal. The equivalent capacitor 211 is a component having a capacitance characteristic at a high frequency current corresponding to the frequency of the excitation signal and is equivalent to a capacitor, such as a microstrip line or a high frequency capacitor spaced from each other. The equivalent inductor 212 is a component, such as an inductor, a microstrip line, or a resistor, having an inductance characteristic and being equivalent to an inductor under a high-frequency current corresponding to the frequency of the excitation signal. Preferably, in the preferred embodiment of the present invention, the equivalent capacitor 211 and the equivalent inductor 212 of the harmonic suppression unit 21 are implemented as microstrip lines etched on the dual-coupled dipole antenna 22.

As shown in fig. 2, the equivalent capacitor 211 of the harmonic suppression unit 21 further includes a first capacitor unit 2111, a second capacitor unit 2112, a third capacitor unit 2113 and a fourth capacitor unit 2114, and the equivalent inductor 212 further includes a first inductor unit 2121, a second inductor unit 2122 and a third inductor unit 2123, wherein the first capacitor unit 2111 and the first inductor unit 2121 are electrically connected to the first antenna unit 221 of the dual-coupled-pole sub-antenna 22, and the first inductor unit 2121 is grounded to the first antenna unit 221 of the dual-coupled-pole sub-antenna 22. The second inductive unit 2122 and the third inductive unit 2123 are connected in series between the first inductive unit 2111 and the signal processing module 10. The second capacitance unit 2112, the third capacitance unit 2113 and the fourth capacitance unit 2114 of the equivalent capacitance 211 are connected in parallel to the first inductance unit 2121, and the second capacitance unit 2112, the third capacitance unit 2113 and the fourth capacitance unit 2114 are respectively grounded. In detail, the second capacitance unit 2112 is connected in series with the first capacitance unit 2111, and is grounded through the second capacitance unit 2112. The third capacitive unit 2113 is connected in series with the first capacitive unit 2111 and the second inductive unit 2122, and is grounded through the third capacitive unit 2113. The fourth capacitive unit 2114 is connected in series with the first capacitive unit 2111, the second inductive unit 2122, and the third inductive unit 2123, and is grounded through the fourth capacitive unit 2114.

It is worth mentioning that, in the preferred embodiment of the present invention, the equivalent capacitor 211 and the equivalent inductor 212 of the harmonic suppression unit 21 satisfy a specific impedance matching relationship based on the frequency characteristics of the microwave detection signal transmitted and received by the dual-coupled dipole antenna 22.

As shown in fig. 3 to 4B, the first antenna element 221 and the second antenna element 222 of the dual-coupled pole antenna 22 are disposed in an axisymmetric manner, and the first antenna element 221 and the second antenna element 222 of the dual-coupled pole antenna 22 are fed by the same source, and when the first antenna element 221 and the second antenna element 222 are fed by the same source, the first antenna element 221 is correspondingly coupled to the second antenna element 222. The first antenna element 221 and the second antenna element 222 of the dual-coupled-pole antenna 22 are fed by the same source, so that the size requirement for coupling between the second antenna element 222 and the first antenna element 221 is reduced. Illustratively, the spacing distance between the second antenna element 222 and the first antenna element 221 is greater than or equal to λ/16 line length, where λ is a wavelength parameter corresponding to the feed signal frequency.

Further, the first antenna element 221 and the second antenna element 222 are adjacently disposed, wherein a distance between the first antenna element 221 and the second antenna element 222 is less than or equal to λ/32, so that the first antenna element 221 and the second antenna element 222 can be coupled to each other when the first antenna element 221 and the second antenna element 222 are respectively fed by the same source. Preferably, the distance between the first antenna element 221 and the second antenna element 222 tends to be λ/128, so that when the first antenna element 221 and the second antenna element 222 are fed from the same source as the first antenna element 221 and the second antenna element 222, respectively, the loss of mutual coupling between the first antenna element 221 and the second antenna element 222 can be reduced to correspondingly increase the gain of the dual-coupled-pole antenna 22.

In the preferred embodiment of the present invention, the first antenna element 221 and the second antenna element 222 are respectively fed and connected to different poles of the same excitation signal source and are fed by the same source. In the preferred embodiment of the present invention, the first antenna unit 221 is electrically connected to the signal processing module 10 through the harmonic suppression unit 21, wherein the feeding end of the second antenna unit 222 is grounded. In other words, the first antenna element 221 is electrically connected to the feed of the excitation signal source of the wireless probe signal, and the second antenna element 222 is electrically connected to the ground of the excitation signal source of the wireless probe signal and is fed by the excitation signal source with respect to the first antenna element.

When the first antenna element 221 and the second antenna element 222 of the dipole antenna 22 are fed by the same source, the first antenna element 221 is correspondingly coupled to the second antenna element 222, and a detection space 201 is formed along the direction in which the first antenna element 221 and the second antenna element 222 correspond, wherein the coverage range of the electromagnetic wave radiated by the dipole antenna 22, that is, the range in which the wireless detection signal can be transmitted, is defined.

As shown in fig. 3 to 4B, the dual-coupled pole sub-antenna 22 further includes a circuit substrate 223, wherein the harmonic suppression unit 21 of the harmonic suppression antenna 20 is disposed on the circuit substrate 223 of the dual-coupled pole sub-antenna 22, or the harmonic suppression unit 21 is formed on the circuit substrate 223. The first antenna element 221 and the second antenna element 222 of the dipole antenna 22 are fixed to the circuit substrate 223, and the second antenna element 222 is grounded via the circuit substrate 223, and the first antenna element 221 is electrically connected to the harmonic suppression unit 21 via the circuit substrate 223.

Preferably, in the preferred embodiment of the present invention, the harmonic suppression unit 21 of the harmonic suppression antenna 20 is formed on the circuit substrate 223. The circuit substrate 223 is provided with at least two electrical connection holes 2230, wherein the first antenna element 221 and the second antenna element 222 of the dual-coupled pole sub-antenna 22 are electrically connected to the circuit substrate 223 through the electrical connection holes 2230.

In detail, the electrical connection hole 2230 penetrates the circuit substrate 223, wherein the first antenna element 221 of the dual-coupled pole sub-antenna 22 passes through the electrical connection hole 2230, and the equivalent capacitance 211 and the equivalent inductance 212 electrically connected to the harmonic suppression unit 21; wherein the second antenna element 222 of the dual-coupled pole sub-antenna 22 is grounded through the electrical connection hole 2230. In the preferred embodiment of the present invention, the mixing detector unit 12 of the signal processing module 10 is disposed on the circuit substrate 223, and the mixing detector unit 12 is electrically coupled to the first antenna unit 221 through the harmonic suppression unit 21. When the oscillation circuit 11 is powered as an excitation signal source, the first antenna unit 221 and the second antenna unit 222 are co-fed by the oscillation circuit 11 to transmit a probe beam and receive an echo of the probe beam, where the echo is received to generate an echo signal.

As will be understood by those skilled in the art, when the first antenna element 221 and the second antenna element 222 are fed by the oscillator circuit 11, the potentials and currents of the first antenna element 221 and the second antenna element 222 are distributed dually, and the second antenna element 222 and the first antenna element 221 are coupled dually. The correlation degree of the signal output by the mix detection unit 13 with the motion of the corresponding object is improved so that the corresponding data processing for the dual-coupled-pole antenna can be simplified, thereby contributing to a reduction in the cost of the dual-coupled-pole antenna 22 and an improvement in the stability and accuracy of the dual-coupled-pole antenna.

The harmonic suppression antenna 20 further includes at least one electromagnetic reflection unit 23, wherein the electromagnetic reflection unit 23 is disposed on the circuit substrate 223 of the dual-coupled pole sub-antenna 22, so that the electromagnetic reflection unit 23 blocks the microwave signal emitted by the dual-coupled pole sub-antenna 22 of the harmonic suppression antenna, and the microwave detection signal emitted by the harmonic suppression antenna is prevented from affecting the external environment. The electromagnetic reflection unit 23 is disposed on the circuit substrate 23, wherein the electromagnetic reflection unit 23 is spaced between the dual-coupled dipole antenna 22 and the harmonic suppression unit 21, so as to avoid interference of microwave detection signals transmitted by the dual-coupled dipole antenna 22 on harmonic suppression network noise signals, thereby improving working stability and anti-interference performance of the harmonic suppression antenna.

Preferably, in the preferred embodiment of the present invention, the electromagnetic reflection unit 23 of the harmonic suppression antenna 20 and the harmonic suppression unit 21 disposed on the circuit substrate 223 are disposed back to back.

As shown in fig. 3 to 4B, the harmonic suppression antenna 20 further includes an antenna holder 24, wherein the antenna holder 24 is disposed on the circuit substrate 223, so that the antenna holder 24 fixes the first antenna unit 221 and the second antenna unit 222 of the dual-coupled-pole antenna 22 on the circuit substrate 223. The first antenna element 221 and the second antenna element 222 of the dual-coupled pole antenna 22 are fixed and maintained by the antenna fixing base 24 with a certain gap, so as to maintain the consistency of the dual-coupled pole antenna in the manufacturing process and the stability in the using process.

The first antenna element 221 of the dual-coupled dipole antenna 22 further comprises a first feeding end 2211 and a first mounting end 2212 integrally extending from the first feeding end 2211, wherein the first feeding end 2211 is electrically connected to the circuit substrate 223 through the first mounting end 2212. The second antenna element 222 further includes a second feeding end 2221 and a second mounting end 2222 integrally extending from the second feeding end 2221, wherein the second mounting end 2222 is electrically connected to the circuit substrate 223. The first antenna element 221 and the second antenna element 222 are arranged and adapted to be fed from the same source at the first feed end 2211 and the second feed end 2221, respectively. The first antenna element 221 is correspondingly coupled to the second antenna element 222 from the second feeding end 2221 along the first antenna element 221 at a corresponding position along the second antenna element 222 from the first feeding end 2211, so as to form a dual coupling manner between the first antenna element 221 and the second antenna element 222. The first antenna element 221 and the second antenna element 222 of the dual-coupled dipole antenna 22 are fed by the same source, and the first feeding end 2211 and the second feeding end 2221 radiate directionally to emit the detection beam outwards to form the detection space 201.

The first mounting end 2212 of the first antenna element 221 and the second mounting end 2222 of the second antenna element 222 are fixedly mounted to the circuit substrate 223 by the antenna fixing base 24, respectively, and the antenna fixing base 24 maintains a distance between the first feeding end 2211 and the second feeding end 2221 by holding the first mounting end 2212 and the second mounting end 2222.

Preferably, in the preferred embodiment of the present invention, the first feeding end 2211 of the first antenna unit 221 and the second feeding end 2221 of the second antenna unit 222 are rod-shaped and parallel to the circuit substrate 223. Optionally, in other optional embodiments of the present invention, the first feeding end 2211 of the first antenna unit 221 and the second feeding end 2221 of the second antenna unit 222 are in an "L" or inverted "L" structure, and the first feeding end 2211 and the second feeding end 2221 are based on the axisymmetric structure of the first mounting end 2212 and the second mounting end 2222.

It will be understood by those skilled in the art that the first mounting end 2212 of the first antenna element 221 and the second mounting end 2222 of the second antenna element 222 are designed according to the distance requirement between the first feeding end 2211 and the second feeding end 2221. Preferably, in the preferred embodiment of the present invention, the ends of the first mounting end 2212 of the first antenna unit 221 and the second mounting end 2222 of the second antenna unit 222 are electrically connected to the circuit substrate 223.

As shown in fig. 4B, the first mounting end 2212 of the first antenna element 221 is electrically connected to the harmonic suppression unit 21 through the circuit board 223, and the second mounting end 2222 of the second antenna element 222 is grounded through the circuit board 223.

As shown in fig. 5, in the preferred embodiment of the present invention, the first capacitor 2111 of the equivalent capacitor 211 of the harmonic suppression unit 21 is implemented as a capacitor, and the second capacitor 2112, the third capacitor 2113 and the fourth capacitor 2114 of the equivalent capacitor 211 are microstrip lines formed on the circuit substrate 223. The first inductance element 2121, the second inductance element 2122, and the third inductance element 2123 of the equivalent inductance 212 are implemented as microstrip lines formed on the circuit substrate 223.

Fig. 7 shows another alternative implementation of the harmonic suppression unit 21 according to the above preferred embodiment of the present invention, wherein the first capacitor unit 2111, the third capacitor unit 2113 and the fourth capacitor unit 2114 of the equivalent capacitor 211 of the harmonic suppression unit 21 are implemented as a capacitor, and the second capacitor unit 2112 of the equivalent capacitor 211 is implemented as a microstrip line formed on the circuit substrate 223. The first inductance element 2121, the second inductance element 2122, and the third inductance element 2123 of the equivalent inductance 212 are implemented as microstrip lines formed on the circuit substrate 223.

Referring to fig. 8 of the drawings accompanying the present application, another alternative embodiment of the microwave detection device according to the above preferred embodiment of the present invention is illustrated in the following description. The microwave detection device comprises a signal processing module 10A and a harmonic suppression antenna 20 electrically connected with the signal processing module 10A, wherein the signal processing module 10A sends an excitation signal of microwaves to the harmonic suppression antenna 20, and the harmonic suppression antenna 20 sends out a microwave detection signal of a specific frequency under the excitation of the signal processing module 10A.

It should be noted that in the preferred embodiment of the present invention, the structure of the harmonic suppression antenna 20 is the same as that of the above preferred embodiment, except that the signal processing module 10A is implemented as a microwave chip or a radio frequency chip, wherein the harmonic suppression antenna 20 is electrically connected to the TX/RX port of the signal processing module 10A.

It will be understood by those skilled in the art that the signal processing module 10A is configured to have the same function as the signal processing module 10A of the above preferred embodiment, wherein the microwave suppression antenna 20 transmits the microwave detection signal under the excitation of the signal processing module 10A, and receives an echo signal of the microwave detection signal reflected by the detected object in the environment, wherein the echo signal received by the harmonic suppression antenna 20 is transmitted to the signal processing module 10A, and the signal processing module 10A obtains a doppler signal corresponding to the detected object based on the doppler effect principle according to the difference between the microwave detection signal and the echo signal transmitted by the harmonic suppression antenna. It will be understood by those skilled in the art that the doppler signal obtained by the signal processing module 10A can be obtained based on the difference between the signals such as the frequency difference or amplitude difference between the microwave detection signal and the echo signal. The signal processing module 10A obtains a fluctuation signal corresponding to the movement of the detected object based on the doppler signal processing, that is, the microwave detecting device processes the signal data of the doppler signal according to the movement characteristic trend of the detected object to obtain the fluctuation signal, so that the fluctuation signal can be used for characterizing the movement characteristic of the detected object.

It will be understood by those skilled in the art that the embodiments of the present invention as described above and shown in the drawings are given by way of example only and are not limiting of the present invention. The objects of the present invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the embodiments without departing from the principles, embodiments of the present invention may have any deformation or modification.

Claims (14)

1. A harmonic rejection antenna, comprising:

a dual-coupling-pole antenna, wherein the dual-coupling-pole antenna comprises a first antenna element and a second antenna element, the first antenna element being adjacently and spaced apart from the second antenna element, the first antenna element and the second antenna element being isostatically fed such that the first antenna element is dual-coupled to the second antenna element; and

a harmonic suppression unit, wherein the harmonic suppression unit comprises at least one equivalent capacitor and at least one equivalent inductor, the equivalent capacitor and the equivalent inductor are electrically connected to the first antenna element of the dual-coupled-pole sub-antenna, so that the harmonic suppression unit electrically connects the first antenna element to a feed of an excitation signal source, and the second antenna element is electrically connected to a ground of the excitation signal source.

2. The harmonic rejection antenna as in claim 1, wherein the equivalent capacitance and the equivalent inductance of the harmonic rejection unit form a frequency selective network having selective characteristics for electrical signals of a frequency interval including the frequency of the excitation signal.

3. The harmonic rejection antenna as in claim 2, wherein the first antenna element is grounded through at least one of the equivalent inductances of the harmonic rejection elements.

4. The harmonic rejection antenna as in claim 3, wherein at least one of the equivalent inductances connecting the first antenna element to ground is provided as a microstrip line.

5. The harmonic rejection antenna as in claim 3, wherein at least one of said equivalent inductances connecting said first antenna element to ground is provided as a resistive element.

6. The harmonic rejection antenna as in claim 3, wherein the equivalent capacitance further comprises a first capacitance unit, a second capacitance unit, a third capacitance unit and a fourth capacitance unit, the equivalent inductor further comprises a first inductor unit, a second inductor unit and a third inductor unit, wherein the first capacitance element and the first inductance element are electrically connected to the first antenna element of the dual-coupled pole sub-antenna, and the first antenna element is grounded through the first inductance element, the second inductance element and the third inductance element are connected in series with the first inductance element, the second capacitor unit, the third capacitor unit and the fourth capacitor unit of the equivalent capacitor are connected in parallel with the first inductor unit, and the second, third and fourth capacitive units are grounded.

7. The harmonic rejection antenna as in claim 6, wherein the second capacitive element is in series with the first capacitive element and is grounded through the second capacitive element, the third capacitive element is in series with the first capacitive element and the second inductive element and is grounded through the third capacitive element, and the fourth capacitive element is in series with the first capacitive element, the second inductive element, and the third inductive element and is grounded through the fourth capacitive element.

8. The harmonic rejection antenna as in claim 7, wherein the first capacitive element of the equivalent capacitance of the harmonic rejection unit is implemented as a capacitive element, and the second capacitive element, the third capacitive element, and the fourth capacitive element of the equivalent capacitance are implemented as microstrip lines.

9. The harmonic rejection antenna as in claim 7, wherein the first, third and fourth capacitive units of the equivalent capacitance of the harmonic rejection unit are implemented as a capacitive element and the second capacitive unit of the equivalent capacitance is implemented as a microstrip line.

10. The harmonic rejection antenna as in any one of claims 1 to 9, wherein the first antenna element and the second antenna element of the dual-coupled pole antenna are disposed axisymmetrically, a separation distance between the second antenna element and the first antenna element being a line length of λ/16 or less, where λ is a wavelength parameter of a corresponding feed signal frequency.

11. The harmonic rejection antenna as in claim 10, wherein the dual-coupled-pole sub-antenna further comprises a circuit substrate to which the first and second antenna elements are secured and the harmonic rejection element is disposed on the circuit substrate to which the second antenna element is grounded.

12. The harmonic rejection antenna as in claim 11, wherein the harmonic rejection antenna further comprises an electromagnetic reflection unit disposed on the circuit substrate, the electromagnetic reflection unit and the harmonic rejection unit being disposed back-to-back based on the circuit substrate.

13. The harmonic rejection antenna as in claim 12, wherein the harmonic rejection antenna further comprises an antenna mount, wherein the first and second antenna elements are secured to the circuit substrate by the antenna mount.

14. The harmonic rejection antenna as in claim 13, wherein the first antenna element further comprises a first feed end and a first mounting end integrally extending from the first feed end, wherein the first feed end is mounted to the circuit substrate through the first mounting end and an end of the first mounting end is electrically connected to the harmonic rejection unit, the second antenna element further comprises a second feed end and a second mounting end integrally extending from the second feed end, wherein the second mounting end is mounted to the circuit substrate.

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