CN216351209U

CN216351209U - Anti-interference half-wave folded antenna microwave detection device

Info

Publication number: CN216351209U
Application number: CN202121531038.3U
Authority: CN
Inventors: 邹高迪; 邹新
Original assignee: Shenzhen Merrytek Technology Co Ltd
Current assignee: Shenzhen Merrytek Technology Co Ltd
Priority date: 2021-04-27
Filing date: 2021-07-07
Publication date: 2022-04-19
Anticipated expiration: 2031-07-07
Also published as: CN215771548U; CN216773510U; CN215771546U; CN217239740U; CN215377682U; CN216354776U; CN216900920U; CN217427078U; CN113131202B; CN217361891U; CN113131203A; CN113131203B; CN215771547U; CN216354774U; CN113131202A; CN217823252U; CN113794048A; CN215816392U; CN215816391U; CN217934208U

Abstract

The utility model relates to the field of microwave detection, in particular to an anti-interference half-wave backfolding antenna microwave detection device, wherein the anti-interference half-wave backfolding antenna microwave detection device has anti-interference frequency selection characteristics for corresponding local oscillator signals and/or feedback signals in a state of being fed and connected to corresponding local oscillator circuits and/or frequency mixing loops, the anti-interference half-wave backfolding antenna microwave detection device adopts an optimized antenna structure design, and the anti-interference half-wave backfolding antenna microwave detection device has longer detection distance, larger detection sector angle and more stable anti-interference capability, and can realize precise microwave detection in a large area and a large area.

Description

Anti-interference half-wave folded antenna microwave detection device

Technical Field

The utility model relates to the field of microwave detection, in particular to an anti-interference half-wave backfolding antenna microwave detection device.

Background

With the development of the internet of things technology, the requirements of artificial intelligence, smart home and intelligent security technology on environment detection, particularly on detection accuracy of human existence, movement and micro motion are higher and higher, and accurate judgment basis can be provided for intelligent terminal equipment only by acquiring a stable enough detection result. Among them, the radio technology, including the microwave detection technology based on the doppler effect principle, is used as a person and an object, and the important junction between the objects has unique advantages in the behavior detection and the existence detection technology, and can detect the action characteristics, the movement characteristics and the micromotion characteristics of a moving object, such as a person, even the heartbeat and the respiration characteristic information of the person without invading the privacy of the person, thereby having wide application prospect.

The conventional microwave detector emits at least one detection beam in a detection space under the excitation of an excitation signal, and receives an echo formed by the detection beam reflected by at least one object in the detection space to generate an echo signal, so as to generate a doppler intermediate frequency signal corresponding to a frequency difference between the excitation signal and the echo signal based on a doppler effect principle, wherein the microwave detector is capable of responding to a full-band electromagnetic wave signal, that is, in the detection space, electromagnetic wave signals of different frequency bands can be responded by the microwave detector to affect the echo signal, and further affect the doppler intermediate frequency signal, that is, the accuracy of the microwave detector, and the doppler intermediate frequency signal can also be directly interfered by an electromagnetic environment of the detection space, that is, the echo signal and the doppler intermediate frequency signal can be interfered by the electromagnetic environment of the detection space, particularly, the low-frequency electromagnetic radiation interference is that on one hand, the doppler intermediate frequency signal corresponding to the human body movement is in the low frequency band and is difficult to completely eliminate the low-frequency electromagnetic interference in a filtering mode, and on the other hand, the low-frequency electromagnetic radiation has strong attenuation resistance and has a large influence on the echo signal and the doppler intermediate frequency signal. The microwave detector in the prior art filters a signal with a lower frequency and a high frequency signal in the doppler intermediate frequency signal based on filtering processing of the doppler intermediate frequency signal, on one hand, simultaneously filters a part of low frequency signal corresponding to human body activity in the doppler intermediate frequency signal so that feedback of the microwave detector to the human body activity is incomplete, on the other hand, filtering processing of the doppler intermediate frequency signal generated based on an echo signal that has been affected by electromagnetic radiation in the environment and the doppler intermediate frequency signal that is further affected by low frequency electromagnetic radiation cannot restore feedback of the doppler intermediate frequency signal to the human body activity, that is, feedback of the microwave detector to the human body activity is incomplete and accurate at present, and the integrity and accuracy of the feedback of the current microwave detector to the human body activity are further limited as the electromagnetic environment becomes more complex.

The microwave detector of the cylindrical radiation source structure is vertical to the reference ground, and compared with the microwave detector of the flat radiation source structure which tends to be a flat plate structure, the microwave detector of the cylindrical radiation source structure easily occupies larger installation space in actual installation, however, the plane size of the microwave detector of the flat radiation source structure in the reference ground direction is directly limited by the area of the reference ground, so that the plane size of the microwave detector of the flat radiation source structure in the reference ground direction is difficult to reduce relative to the plane size of the microwave detector of the cylindrical radiation source structure in the reference ground direction. That is to say, although the microwave detector of the flat-panel radiation source structure can occupy a smaller installation space than the microwave detector of the columnar radiation source structure in actual installation, the area of the reference ground of the microwave detector of the columnar radiation source structure is allowed to be smaller than the area of the reference ground of the microwave detector of the flat-panel radiation source structure, and accordingly, when the installation scene of the microwave detector of the columnar radiation source structure in the occupation space in the columnar radiation source direction does not need to be considered, the microwave detector of the columnar radiation source structure can occupy a smaller installation space than the microwave detector of the flat-panel radiation source structure. Therefore, the microwave detector with the columnar radiation source structure still has wide application requirements. However, the existing microwave detector with a columnar radiation source structure has a large backward lobe by taking the reference ground as a boundary, and a concave detection dead zone is arranged in the extending direction of two ends of the columnar radiation source by taking the columnar radiation source as a central axis, corresponding to the condition that the detection area of the microwave detector forming the columnar radiation source structure can not be matched with the target space, such as a situation where the detection zone coincides with the target space section across, such that the target space outside the detection zone cannot be effectively detected, and/or the detection area outside the target space has an environment interference state, including action interference, electromagnetic interference and self-excitation interference caused by an electromagnetic shielding environment, so that the microwave detector with the columnar radiation source structure has the problems of poor detection accuracy and/or poor anti-interference performance. In other words, the existing microwave detector with a cylindrical radiation source structure has poor detection stability in practical application and has limited adaptability to different application scenarios in practical application. In addition, the cylindrical radiation source of the microwave detector with the existing cylindrical radiation source structure has a high height in a direction perpendicular to the reference ground, and certain requirements are provided for the structural form of the corresponding microwave detection device of the microwave detector with the cylindrical radiation source structure. In addition, whether the microwave detector is of a cylindrical radiation source structure or a flat radiation source structure, the coupling energy forming the radiation space is mainly concentrated between the reference ground and the corresponding radiation source, and the resonance stability of the corresponding microwave detector has severe electrical parameter requirements on the medium between the reference ground and the corresponding radiation source and the reference ground, so that the corresponding microwave detector needs to be arranged on the corresponding microwave detection device in an independent modular structure comprising the reference ground and the corresponding radiation source in actual use, and the structure of the corresponding microwave detection device has further requirements, and is not beneficial to cost control and automatic production control.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to provide an anti-interference half-wave folded antenna microwave detection device, which has an anti-interference frequency selection characteristic for a corresponding local oscillator signal and/or a feedback signal in a state of being fed and connected to a corresponding local oscillator circuit and/or a frequency mixing loop, so as to reduce interference of electromagnetic radiation in an environment different from a working frequency band of the anti-interference half-wave folded antenna microwave detection device on the anti-interference half-wave folded antenna microwave detection device, and in particular, to filter and suppress low-frequency band electromagnetic radiation (such as bluetooth and WiFi signals in a 2.5GHz band) having a strong anti-attenuation characteristic, so as to improve detection accuracy of the anti-interference half-wave folded antenna microwave detection device.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detection device, wherein the anti-jamming half-wave folded antenna microwave detection device includes at least one frequency selection unit, wherein the frequency selection unit is configured to form a high-pass filter network in the anti-jamming half-wave folded antenna microwave detection device, so as to selectively allow the electric signal in the specific frequency range to pass through by the high-pass filter network, thereby reducing interference of electromagnetic radiation in an environment different from an operating frequency band of the anti-jamming half-wave folded antenna microwave detection device on the anti-jamming half-wave folded antenna microwave detection device.

Another object of the present invention is to provide a microwave detecting apparatus of a half-wave folded antenna for noise immunity, wherein the microwave detecting apparatus of a half-wave folded antenna for noise immunity includes an antenna unit, wherein the antenna unit includes at least one half-wave oscillator and a reference ground, wherein a state in which both ends of the half-wave oscillator are close to each other within a distance range of λ/128 or more and λ/6 or less is formed by folding back the half-wave oscillator, such that both ends of the half-wave oscillator can be coupled to each other when a phase difference is formed between both ends of the half-wave oscillator based on a corresponding feeding structure, and then the half-wave oscillator is close to the reference ground with both ends thereof within a distance range of λ/128 or more, and wherein at least one end is spaced apart from the reference ground in a state in which the distance range of λ/6 or less is close to the reference ground, the energy of direct coupling between the end part of the half-wave oscillator and the reference ground can be reduced, so that obvious resonance frequency points can be generated based on the coupling between the two ends of the half-wave oscillator while the directional radiation of the antenna unit is formed, the matching with a corresponding target space is correspondingly facilitated, the selectivity of received reflected echoes is achieved, and the microwave detection device is suitable for microwave detection based on the Doppler effect principle.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detection apparatus, wherein the half-wave oscillator has a wavelength electrical length greater than or equal to 1/2 and less than or equal to 3/4, so as to facilitate forming a phase difference tending to reverse between two ends of the half-wave oscillator based on a corresponding feed structure, and further facilitate maximizing energy mutually coupled between two ends of the half-wave oscillator, thereby improving gain of the antenna unit and generating an obvious resonant frequency point.

Another object of the present invention is to provide an anti-jamming half-wave backfolding antenna microwave detecting device, wherein the half-wave oscillator has at least one feeding point, wherein when the number of the feeding points is one, the electrical length between the feeding point and one end of the half-wave oscillator along the half-wave oscillator is less than or equal to 1/6, and the end is correspondingly named as a feeding end of the half-wave oscillator, wherein the other end of the half-wave oscillator is far from the reference ground relative to the feeding end, i.e. the distance between the other end of the half-wave oscillator and the reference ground is greater than the distance between the feeding end and the reference ground, so that when the feeding point feeds the half-wave oscillator, a layer order distribution with a current density from high to low can be formed on the half-wave oscillator in a direction from the other end of the half-wave oscillator to the reference ground, therefore, the energy directly coupled between the two end parts of the half-wave oscillator and the reference ground is further reduced, the vector superposition of the electric field between the two end parts of the half-wave oscillator and the reference ground is formed, and the gain of the antenna unit is further improved while obvious resonance frequency points are generated.

Another object of the present invention is to provide an anti-interference microwave detecting apparatus with a half-wave folded antenna, wherein when the number of the feeding points is two, two of the feeding points are located between two ends of the half-wave oscillator, wherein the half-wave oscillator has an electrical length equal to or greater than 1/6 wavelengths from any end along the half-wave oscillator to the feeding point close to the end, and has an electrical length equal to or less than 1/4 wavelengths from one of the feeding points along the half-wave oscillator to the other feeding point, so that when two feeding points are respectively connected to two poles of a local oscillator signal or a local oscillator signal having a phase difference to feed the half-wave oscillator, a phase difference tending to reverse phase can be formed between two ends of the half-wave oscillator, thereby facilitating to maximize the energy mutually coupled between two ends of the half-wave oscillator and increase the gain of the antenna unit, and the two ends of the half-wave oscillator are close to the state of the reference ground within the distance range of more than or equal to lambda/128 and less than or equal to lambda/6 to generate obvious resonance frequency points, wherein the resonance frequency points of the antenna unit can be designed to be matched with corresponding working frequency points through the selection of different positions of the feed points and/or the morphological design of the half-wave oscillator between the two feed points, so that the anti-interference performance of the antenna unit is favorably ensured, and the antenna unit is simple and easy to operate and is favorable for ensuring the consistency and reliability of the antenna unit in batch production.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detecting device, wherein the antenna unit further includes at least one feeding line, wherein when the number of the feeding lines is one, the number of the feeding points corresponding to the half-wave oscillator is one, wherein one end of the feeding line is electrically connected to the feeding points of the half-wave oscillator, wherein the feeding line has an electrical length greater than or equal to 1/128 and less than or equal to 1/4, so that when the feeding line is electrically coupled to the feeding circuit at the other end thereof and receives the local oscillator signal, the feeding line is electrically connected to the feeding points via the feeding line in a state where the half-wave oscillator is spaced from the reference ground, and the half-wave oscillator is fed at the feeding points of the half-wave oscillator.

Another objective of the present invention is to provide an anti-interference microwave detecting apparatus for a half-wave folded antenna, wherein when the number of the feeder lines is two, the number of the feed points corresponding to the half-wave oscillator is two, wherein one end of each of the feeder lines is electrically connected to the feed points of the half-wave oscillator, so that two poles of local oscillator signals or a local oscillator signal having a phase difference are connected to the two feeder lines at the other ends of the feeder lines by electrically coupling the two feeder lines to corresponding feed circuits, and the feeder lines are electrically connected to the half-wave oscillator at a position where the half-wave oscillator is spaced from the reference ground, and the half-wave oscillator is fed by the feed points of the half-wave oscillator.

Another object of the present invention is to provide an anti-jamming half-wave backfolding antenna microwave detecting apparatus, wherein the resonant frequency point of the antenna unit is determined by the half-wave oscillator, the stub load and the feeder line wavelength electrical length under the limitation of the fixed connection relationship among the half-wave oscillator, the stub load and the feeder line wavelength electrical length, and the connection relationship among the half-wave oscillator, the stub load and the feeder line wavelength electrical length and each other are maintained unchanged, the working parameters of the antenna unit are difficult to be influenced based on the batch production error and the slight deformation of the half-wave oscillator formed by daily use, the corresponding anti-jamming half-wave backfolding type microwave detector has good consistency and stability, and is favorable for reducing the precision requirement for batch production and reducing the production cost of the anti-jamming half-wave backfolding antenna microwave detecting apparatus, and the industrial value of the anti-interference half-wave folded antenna microwave detection device is improved.

Another object of the present invention is to provide an anti-jamming half-wave folded antenna microwave detecting device, wherein based on the adjustment of the distance between the two ends of the half-wave oscillator of the antenna unit and the reference ground, when the distance between the two ends of the half-wave oscillator and the reference ground is greater than the distance between the radiation gaps of the microwave detector of the existing flat radiation source structure, the beam angle of the anti-jamming half-wave folded antenna microwave detecting device can be increased relative to the microwave detector of the flat radiation source structure, corresponding to a vertical detection application, when the installation heights are the same, the area of the detection region covered by the anti-jamming half-wave folded antenna microwave detecting device is larger, and in a horizontal detection application, the radiation sector angle of the anti-jamming half-wave folded antenna microwave detecting device is larger, the corresponding detection region is larger, the anti-interference half-wave folded antenna microwave detection device has longer detection distance and larger detection sector angle, can realize large-area and large-area microwave detection, and improves the detection stability and detection accuracy of the anti-interference half-wave folded antenna microwave detection device.

Another object of the present invention is to provide an anti-interference half-wave folded antenna microwave detecting apparatus, wherein the frequency selecting unit includes an equivalent capacitor and a pair of ground equivalent inductors, wherein in a state where the antenna unit is fed and connected to the local oscillator circuit and/or the frequency mixing loop through the feeder line, one pole of the equivalent capacitor is fed and connected to the feeder line, and the other pole of the equivalent capacitor is fed and connected to the local oscillator circuit and/or the frequency mixing loop, so as to form a feeding path between the feeder line and the local oscillator circuit and/or the frequency mixing loop, thereby forming a state where the antenna unit is fed and connected to the local oscillator circuit and/or the frequency mixing loop through the feeder line and the feeding path, and wherein the pair of ground equivalent inductors are led out from the feeding path in a state where the pair of ground equivalent inductors are electrically connected to the other pole of the equivalent capacitor, and are led out from the feeding path to the equivalent capacitor And a frequency selection network with high-pass characteristic is formed, so that the interference of electromagnetic radiation in the working frequency band different from the working frequency band of the anti-interference half-wave folded antenna microwave detection device in the environment on the echo signal of the anti-interference half-wave folded antenna microwave detection device is reduced, and the detection accuracy of the anti-interference half-wave folded antenna microwave detection device is improved.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detection device, wherein the anti-jamming half-wave folded antenna microwave detection device further includes a ground preselection inductor, wherein the ground preselection inductor is led out from the feed path in a state of being electrically connected to the feeder line, so as to preselection and filter a low-frequency band signal, thereby reducing interference of electromagnetic radiation in an environment different from an operating frequency band of the anti-jamming half-wave folded antenna microwave detection device on the anti-jamming half-wave folded antenna microwave detection device, and further improving detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detection device, wherein the anti-jamming half-wave folded antenna microwave detection device further includes at least one series resonant network led out from the feed path, wherein the series resonant network includes a first equivalent capacitor led out from the feed path and a first equivalent inductance to ground connected in series with the first equivalent capacitor, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

Another objective of the present invention is to provide an anti-jamming half-wave folded antenna microwave detection device, wherein the anti-jamming half-wave folded antenna microwave detection device is further disposed on at least one parallel resonant network of the feed path, wherein the parallel resonant network includes a second equivalent capacitor disposed on the feed path in series with the equivalent capacitor, and a second equivalent inductor connected in parallel with the second equivalent capacitor, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

Another objective of the present invention is to provide an anti-interference half-wave folded antenna microwave detection device, which has an anti-interference frequency selection characteristic for a corresponding local oscillator signal and/or a feedback signal in a state of being fed and connected to a corresponding local oscillator circuit and/or a frequency mixing loop, and the antenna unit of the anti-interference half-wave folded antenna microwave detection device adopts an optimized structural design, and the anti-interference half-wave folded antenna microwave detection device has a longer detection distance, a larger detection sector angle, and a more stable anti-interference capability, so that the anti-interference half-wave folded antenna microwave detection device can realize precise microwave detection in a large area.

According to an aspect of the present invention, there is provided an anti-interference half-wave folded antenna microwave detection device having an anti-interference frequency selection characteristic for a corresponding local oscillator signal and/or a feedback signal in a state of being fed to a corresponding local oscillator circuit and/or a mixer circuit, the anti-interference half-wave folded antenna microwave detection device including:

an antenna unit, wherein the antenna unit comprises at least a half-wave oscillator, a reference ground and at least a feeding line, wherein the half-wave oscillator has a wavelength electrical length greater than or equal to 1/2 and less than or equal to 3/4, wherein the half-wave oscillator is folded back to form a state in which a distance between both ends thereof is greater than or equal to λ/128 and less than or equal to λ/6, wherein the half-wave oscillator has a feeding point such that both ends thereof are coupled to each other with a phase difference tending to be in antiphase in a state in which the half-wave oscillator is fed by being connected to the local oscillation signal at the feeding point, wherein λ is a wavelength parameter corresponding to a frequency of the local oscillation signal, wherein the half-wave oscillator is spaced from the reference ground with a distance between both ends thereof and the reference ground being greater than or equal to λ/128, and wherein a distance between at least one end and the reference ground is less than or equal to λ/6, wherein one end of the feed line is electrically connected to the feed point of the half-wave oscillator, wherein the feed line has an electrical length of a wavelength greater than or equal to 1/128 and less than or equal to 1/4, so that when the feed line is connected at its other end to the local oscillator circuit and/or the mixer circuit, the feed line feeds the half-wave oscillator at the feed point of the half-wave oscillator in a state where the feed point is electrically connected to the half-wave oscillator at a distance from the reference ground; and

at least one frequency selection unit, wherein the frequency selection unit comprises an equivalent capacitor and a pair of ground equivalent inductors, wherein in a state where the antenna unit is fed to be connected to the local oscillation circuit and/or the mixing loop via the feeder line, one pole of the equivalent capacitance is fed and connected to the feeder line, the other pole of the equivalent capacitance is fed and connected to the local oscillation circuit and/or the mixing loop, so as to form a feeding path between the feeding line and the local oscillator circuit and/or the mixing loop to form a state that the antenna unit is fed by the local oscillator circuit and/or the mixing loop through the feeding line and the feeding path, the equivalent inductance to ground is led out from the feed path in a state of being electrically connected with the other pole of the equivalent capacitance, and forms a frequency-selecting network with high-pass characteristic with the equivalent capacitance.

In an embodiment, the equivalent capacitance is equivalently formed by at least two capacitances based on a series and/or parallel connection relationship.

In an embodiment, the equivalent capacitance is a circuit structure with capacitance characteristics equivalently formed on the corresponding circuit board based on the coupling between the conductors with gaps

In one embodiment, the equivalent inductance to ground is equivalently formed by the connection relationship of at least two inductances based on series connection.

In an embodiment, the equivalent inductance to ground is configured in a microstrip line.

In an embodiment, the frequency selecting unit further includes a transmission equivalent inductor, wherein the transmission equivalent inductor is disposed in the feeding path in series with the equivalent capacitor, so as to suppress high-frequency signals above an operating frequency band of the microwave detecting device with the anti-jamming half-wave folded antenna.

In one embodiment, the microwave detection device further comprises a ground pre-selection inductor, wherein the ground pre-selection inductor is led out from the feed path in a state of being electrically connected with the feeder line so as to pre-select and filter low-frequency band signals.

In one embodiment, the microwave detecting apparatus further includes at least one series resonant network led out from the feed path, wherein the series resonant network includes a first equivalent capacitor led out from the feed path and a first equivalent inductance to ground connected in series with the first equivalent capacitor, so as to filter out the interference signal at specific frequency points.

In an embodiment, the microwave detecting apparatus further includes at least one parallel resonant network disposed in the feeding path, wherein the parallel resonant network includes a second equivalent capacitor disposed in the feeding path in series with the equivalent capacitor, and a second equivalent inductor connected in parallel with the second equivalent capacitor, so as to block interference signals at specific frequency points.

According to another aspect of the present invention, there is provided an anti-interference half-wave folded antenna microwave detecting apparatus having an anti-interference frequency selection characteristic for a corresponding local oscillator signal and/or a feedback signal in a state of being fed to a corresponding local oscillator circuit and/or a mixer circuit, the anti-interference half-wave folded antenna microwave detecting apparatus including:

an antenna unit, wherein the antenna unit includes a half-wave oscillator, a reference ground and two feeding lines, wherein the half-wave oscillator has a wavelength electrical length greater than or equal to 1/2 and less than or equal to 3/4, and has two coupling sections, wherein each coupling section has a wavelength electrical length greater than or equal to 1/6, one end of each coupling section is named as a feeding end of the coupling section, and the other end of each coupling section is named as two ends of the half-wave oscillator, wherein a distance between the two feeding ends is less than or equal to λ/4, a distance between the two ends of the half-wave oscillator is greater than or equal to λ/128 and less than or equal to λ/6, so as to feed the half-wave oscillator by accessing two poles of the local oscillator signal or accessing the local oscillator signal with a phase difference at the two feeding ends respectively, two ends of the half-wave oscillator can form phase difference to be coupled with each other, wherein lambda is a wavelength parameter corresponding to the frequency of the local oscillator signal, the half-wave oscillator is spaced from the reference ground in a state that the distance between the two ends of the half-wave oscillator and the reference ground is greater than or equal to lambda/128 and less than or equal to lambda/6, the two feeder lines are respectively and electrically connected to the corresponding feed ends, so that when the two feeder lines are connected with the local oscillator circuit and/or the mixing circuit in a feed mode, the feeder lines are electrically connected with the feed ends in a state that the half-wave oscillator is spaced from the reference ground, and the half-wave oscillator is fed by the feed ends of the half-wave oscillator;

In one embodiment, the equivalent capacitance is a circuit structure with capacitance characteristics equivalently formed on the corresponding circuit board based on the coupling between the conductors with gaps.

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

Drawings

Fig. 1 is a block diagram of a microwave detecting apparatus with a half-wave folded antenna for resisting disturbance according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of an antenna unit of the microwave detecting apparatus with a tamper-resistant half-wave folded antenna according to the above embodiment of the present invention.

Fig. 3 is a schematic structural diagram of an alternative implementation of the antenna unit of the microwave detection apparatus with a half-wave folded antenna for immunity against interference according to the above embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a modified example of the above-mentioned optional implementation of the antenna unit of the tamper-resistant half-wave folded antenna microwave detection device according to the above-mentioned embodiment of the present invention.

Fig. 5 is a partial equivalent circuit structure of the microwave detecting apparatus with a half-wave folded antenna for resisting disturbance according to the above embodiment of the present invention.

FIG. 6 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 7 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 8 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 9A is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 9B is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 10 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 11 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 12 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

FIG. 13 is a partial equivalent circuit structure of a microwave detecting device with a half-wave folded antenna for immunity against interference according to another embodiment of the present invention.

Detailed Description

The following description is presented to disclose the utility model so as to enable any person skilled in the art to practice the utility model. 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 utility model, 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 utility model.

It will be understood by those skilled in the art that in the present disclosure, the terms "vertical," "lateral," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, the above terms should not be construed as limiting the present invention.

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.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The utility model provides an anti-interference half-wave folded antenna microwave detection device, wherein the anti-interference half-wave folded antenna microwave detection device has anti-interference frequency selection characteristics on corresponding local oscillator signals and/or feedback signals in a state of being fed and connected to corresponding local oscillator circuits and/or frequency mixing loops, interference of electromagnetic radiation in an environment different from a working frequency band of the anti-interference half-wave folded antenna microwave detection device on the anti-interference half-wave folded antenna microwave detection device is reduced, particularly low-frequency band electromagnetic radiation (such as Bluetooth and WiFi signals in a 2.5GHz frequency band) with strong anti-attenuation characteristics is filtered and suppressed, and detection accuracy of the anti-interference half-wave folded antenna microwave detection device is improved.

It is worth mentioning that the anti-interference half-wave folded antenna microwave detection device is based on the optimized structural design of the antenna unit, and the anti-interference half-wave folded antenna microwave detection device has a farther detection distance and a larger detection sector angle, so that the anti-interference half-wave folded antenna microwave detection device can realize large-area microwave detection, and the detection stability and the detection accuracy of the anti-interference half-wave folded antenna microwave detection device are improved.

Referring specifically to fig. 1 of the drawings of the specification of the present invention, a block diagram of a structure of an anti-interference half-wave folded antenna microwave detection device according to an embodiment of the present invention is illustrated, where the anti-interference half-wave folded antenna microwave detection device includes an antenna unit 10 and at least one frequency selecting unit 20, where the anti-interference half-wave folded antenna microwave detection device has an anti-interference frequency selecting characteristic for an anti-interference frequency selecting characteristic of a corresponding local oscillator signal and/or a feedback signal in a state of being fed and connected to a corresponding local oscillator circuit and/or a frequency mixing loop, so as to reduce interference of electromagnetic radiation in an environment different from an operating frequency band of the anti-interference half-wave folded antenna microwave detection device on the anti-interference half-wave folded antenna microwave detection device.

In particular, the antenna unit 10 has a high gain characteristic, that is, the antenna unit 10 has a high transmission efficiency and a high receiving sensitivity, wherein based on the filtering and suppressing of the frequency selecting unit 20 to the interference signal different from the working frequency band of the anti-interference half-wave folded antenna microwave detecting device, especially the filtering and suppressing of the interference signal of the low frequency band, the interference of the interference signal different from the working frequency band of the anti-interference half-wave folded antenna microwave detecting device to the half-wave folded microwave detecting device is reduced.

It should be noted that, based on the frequency selecting unit 20, the local oscillator signal generates a fixed phase shift to the signal finally transmitted by the antenna unit 10, and the feedback signal and the local oscillator signal have the fixed phase shift simultaneously, a frequency difference and a phase shift generated by the feedback signal when the reflection of the moving object is detected are superimposed on the fixed phase shift, and the feedback signal and the local oscillator signal are mixed and detected by the mixing loop to obtain a doppler intermediate frequency signal to realize the active detection, when the anti-interference half-wave folded antenna microwave detection apparatus is applied to a high reflection environment, such as a large area metal, a large area thick glass, etc., to generate strong reflection and multiple reflections, since the feedback signal already has the fixed phase shift, the output of the mixing loop enters a linear working interval, therefore, the noise output of the mixing loop under the environment conditions of strong reflection and multiple reflection is reduced, and the working stability of the anti-interference half-wave folded antenna microwave detection device is improved.

With further reference to fig. 2 of the drawings of the present specification, the structure of the antenna unit 10 of the tamper resistant half-wave folded-back antenna microwave detection device is illustrated, wherein the antenna unit 10 includes at least one half-wave oscillator 11 and a reference ground 12, wherein by folding back the half-wave oscillator 11, a state is formed in which both ends of the half-wave oscillator 11 are close to each other within a distance range of λ/128 or more and λ/6 or less, such that both ends of the half-wave oscillator 11 can be coupled to each other and have relatively high coupling energy when a phase difference is formed between both ends of the half-wave oscillator 11 based on the corresponding feeding structure, and then both ends of the half-wave oscillator 11 are close to the reference ground 12 within a distance range of λ/128 or more, and wherein at least one end is close to the reference ground 12 within a distance range of λ/6 or less and spaced apart from the reference ground 12 When the microwave detection device is arranged, the energy of direct coupling between the end part of the half-wave oscillator 11 and the reference ground 12 can be reduced, so that obvious resonance frequency points can be generated based on the coupling between the two ends of the half-wave oscillator 11 while the directional radiation of the antenna unit 10 is formed, the matching with a corresponding target space is correspondingly facilitated, the selectivity of the received reflection echo is realized, and the microwave detection device is suitable for microwave detection based on the Doppler effect principle.

Specifically, the half-wave oscillator 11 has a wavelength electrical length greater than or equal to 1/2 and less than or equal to 3/4, so as to facilitate forming a phase difference tending to reverse phase between two ends of the half-wave oscillator 11 based on the corresponding feeding structure, and further, when the half-wave oscillator 11 is folded back in a state where the two ends of the half-wave oscillator are close to each other within a distance range greater than or equal to λ/128 and less than or equal to λ/6, energy mutually coupled between the two ends of the half-wave oscillator 11 tends to be maximized, so that the gain of the antenna unit 10 is increased and an obvious resonant frequency point is generated.

Further, in this embodiment of the utility model, the half-wave vibrator 11 has one feeding point 110, wherein the feeding point 110 and one end of the half-wave element 11 have an electrical length of 1/6 or less along the half-wave element 11, correspondingly named as the feed end 111 of the half-wave oscillator 11, in this embodiment of the utility model, the feed point 110 is located at the feed end 111, so that when the half-wave vibrator 11 is fed at the feeding point 110, the half-wave vibrator 11 is set to have an electrical length equal to or greater than 1/2 and equal to or less than 3/4, and a structure form in which both ends of the half-wave oscillator 11 are close to each other in a distance range of λ/128 or more and λ/6 or less, the two ends of the half-wave vibrator 11 can be coupled with each other and have relatively high coupling energy.

Preferably, the other end of the half-wave oscillator 11 is disposed away from the reference ground 12 with respect to the feeding end 111, namely, the distance between the other end of the half-wave oscillator 11 and the reference ground 12 is greater than or equal to the distance between the feeding terminal 111 and the reference ground 12, thus, when the feeding point 110 feeds the half-wave oscillator 11, a step distribution with a current density from high to low can be formed in the half-wave oscillator 11 in the direction from the other end of the half-wave oscillator 11 to the reference ground 12, thereby contributing to further reducing the energy directly coupled between both ends of the half-wave vibrator 11 and the reference ground 12, and a vector of an electric field formed between both end portions of the half-wave vibrator 11 and an electric field between both end portions of the half-wave vibrator 11 and the reference ground 12 is superimposed, thereby further improving the gain of the antenna unit 10 while generating an obvious resonance frequency point.

Further, the antenna unit 10 includes a feeding line 13 corresponding to the number of the half-wave oscillators 11 and a circuit substrate 14, wherein the reference ground 12 is carried on the circuit substrate 14, wherein one end of the feeding line 13 is fixed to the circuit substrate 14, wherein the reference ground 12 is provided with an isolation hole 121, wherein the feeding line 13 penetrates the reference ground 12 through the isolation hole 121 to form an isolation gap 1211 with the reference ground 12 and is electrically isolated from the reference ground 12 in a physical structure, wherein the other end of the feeding line 13 is electrically connected to the feeding end 111 of the half-wave oscillator 11, so as to be electrically connected to the feeding end 111 of the half-wave oscillator 11 and physically support the half-wave oscillator 11 through the feeding line 13 when the feeding line 13 is connected to the local oscillator circuit and/or the mixer circuit, the half-wave vibrator 11 is formed in a state where the feeding terminal 111 is fed and is disposed spaced apart from the reference ground 12.

Further, one end of the power feeding line 13 is electrically connected to the power feeding terminal 111 of the half-wave oscillator 11, that is, one end of the power feeding line 13 is electrically connected to the power feeding point 110 of the half-wave oscillator 11, wherein the power feeding line 13 has a wavelength electrical length greater than or equal to 1/128 and less than or equal to 1/4, so that when the power feeding line 13 is electrically connected to the local oscillator circuit and/or the mixer circuit at the other end thereof, the half-wave oscillator 11 is fed at the power feeding point 110 of the half-wave oscillator 11 in a state where the power feeding point 110 is electrically connected to the half-wave oscillator 11 and the half-wave oscillator 11 is spaced from the reference ground 12 through the power feeding line 13.

It should be noted that the feeding connection between the feeding line 13 and the local oscillator circuit and/or the frequency mixing loop is a path connection under the action of a high-frequency electrical signal, so that the feeding connection between the feeding line 13 and the local oscillator circuit and/or the frequency mixing loop is allowed to be in a direct-connection path connection form in an entity circuit, or is in an open-circuit connection form coupled through a corresponding capacitor (such as a microstrip coupling capacitor, a distributed capacitor, and a capacitor element), which is not limited in this respect.

In particular, in this embodiment of the present invention, in which the power feeding line 13 is integrally designed with the half-wave vibrator 11, in other words, the power feeding line 13 extends integrally with the half-wave vibrator 11 at the power feeding end 111 of the half-wave vibrator 11, the structure of the half-wave vibrator 11 is defined in the description of "the half-wave vibrator has a wavelength electrical length equal to or greater than 1/2 and equal to or less than 3/4" and "both ends of the half-wave vibrator 11 are close to each other within a distance range equal to or greater than λ/128 and equal to or less than λ/6" and "the half-wave vibrator 11 is close to the reference ground with both ends thereof within a distance range equal to or greater than λ/128" and at least one end thereof is provided at a distance from the reference ground 12 in a state of being close to the reference ground 12 within a distance range equal to or less than λ/6 "," the structure of the half-wave vibrator 11 is defined, in a state where the feeding line 13 is electrically connected to the feeding terminal 111 of the half-wave oscillator 11, the definition of the feeding terminal 111 of the half-wave oscillator 11 may not be unique, that is, there may be a plurality of positions on the half-wave oscillator 11 that satisfy the above description of the feeding terminal 111. Therefore, it is worth mentioning that in a state that the feeder line 13 is electrically connected to the feeding end 111 of the half-wave oscillator 11, the other end of the half-wave oscillator 11 is taken as a definite end, and when the feeding end 111 satisfying the above description exists on the half-wave oscillator 11, the two ends of the half-wave oscillator 11 can be coupled with each other and have relatively high coupling energy, so that an obvious resonant frequency point can be generated based on the coupling between the two ends of the half-wave oscillator 11 while forming the directional radiation of the antenna unit 10.

Preferably, in this embodiment of the present invention, the feeder 13 is set to have an electrical length of 1/4 or less, so as to reduce the coupling between the feeder 13 and the reference ground 12, thereby facilitating the formation of directional radiation and generating a significant resonant frequency point, and simultaneously improving the gain of the antenna unit 10 and avoiding the formation of a detection dead zone in the directional radiation direction.

Further, the power feed line 13 is provided with a wavelength electrical length of 1/128 or more, so that a state in which the half-wave vibrator 11 is provided with both ends spaced from the reference ground 12 in a distance range of λ/128 or more is formed in a state in which the half-wave vibrator 11 can be physically supported by the power feed line 13 in a medium space of air.

It should be noted that, in this embodiment of the present invention, the antenna unit 10 is further provided with at least one stub load 15, where the stub load 15 is loaded on the half-wave oscillator 11, so as to set the electrical length of the wavelength of the stub load 15 and debug the load position of the half-wave oscillator 11, the resonant frequency point of the antenna unit 10 can be debugged to match with the corresponding operating frequency point, and the number, form, electrical length of the wavelength, and load position of the stub load 15 are varied and do not limit the present invention.

In particular, the half-wave oscillator 11 is designed in a columnar strip form, wherein the feeder line 13 is designed to be thickened with respect to the half-wave oscillator 11 designed in the columnar strip form, so as to improve the structural stability of the antenna unit 10 by improving the supporting strength of the feeder line to the half-wave oscillator 11 while tuning the resonance frequency point of the antenna unit 10 to match the corresponding operating frequency based on the thickened design of the feeder line 13.

It should be noted that, in some embodiments of the present invention, on the basis that the branch load 15 is loaded on the half-wave oscillator 11, the half-wave oscillator 11 is designed in a long strip shape, and the thick design of the half-wave oscillator 11 formed by loading another branch load 15 on the half-wave oscillator 11 in a direction perpendicular to the half-wave oscillator 11 is equivalent to that, so as to form the matching between the resonant frequency point and the operating frequency point of the antenna unit 10, which is not limited in this respect.

With further reference to fig. 3 of the drawings accompanying the present specification, an alternative embodiment of the antenna unit 10 of the tamper resistant half-wave folded antenna microwave detection device is illustrated, in which the antenna unit 10 includes a half-wave element 11 and a reference ground 12, the half-wave element 11 satisfies structural limitations of "the half-wave element has a wavelength electrical length equal to or greater than 1/2 and equal to or less than 3/4" and "both ends of the half-wave element 11 are close to each other within a distance range equal to or greater than λ/128 and equal to or less than λ/6", and the half-wave element 11 is disposed at a distance from the reference ground 12 in a state where both ends of the half-wave element are close to the reference ground 12 within a distance range equal to or greater than λ/128 and equal to or less than λ/6.

Further, in this alternative embodiment, the half-wave oscillator 11 has two feeding points 110, wherein the two feeding points 110 are located between two ends of the half-wave oscillator 11, wherein the half-wave oscillator 11 has an electrical length equal to or greater than 1/6 wavelength from either end along the half-wave oscillator 11 to the feeding point 110 near the end, and has an electrical length equal to or less than 1/4 wavelength from one of the feeding points 110 along the half-wave oscillator 11 to the other feeding point 110, corresponding to a physical distance equal to or less than λ/4 between the two feeding points 110, so that when the two feeding points 110 are respectively connected to two poles of the local oscillator signal or connected to the local oscillator signal having a phase difference to feed the half-wave oscillator 11, a phase difference tending to reverse phase can be formed between two ends of the half-wave oscillator 11, and then it is favorable to make the energy of mutual coupling between the two ends of the half-wave oscillator 11 tend to maximize and improve the gain of the antenna unit 10, and generate obvious resonance frequency points at the two ends of the half-wave oscillator 11 in a state of being close to the reference ground within a distance range of λ/128 or more and λ/6 or less.

It is worth mentioning that, the half-wave oscillator 11 has two coupling sections 112 extending from two ends thereof as starting ends, wherein the coupling section 112 has an electrical length equal to or greater than 1/6 wavelength from the end of the feeding point 110, wherein one end of the coupling section 112 from the feeding point 110 is named as the feeding end 111 of the coupling section 112, that is, the other ends of the two coupling sections 112 are two ends of the half-wave oscillator 11 and are close to each other in a distance range equal to or greater than λ/128 and equal to or less than λ/6, and have a distance equal to or greater than λ/128 and equal to or less than λ/6 from the reference ground 12, and have a physical distance equal to or less than λ/4 from the corresponding feeding end 111, so that when two feeding ends 111 respectively access two poles of the local oscillation signal or access the local oscillation signal with a phase difference to feed the half-wave oscillator 11, a phase difference tending to be opposite in phase can be formed between the two ends of the half-wave oscillator 11, which is further beneficial to maximizing the energy mutually coupled between the two coupling sections 112 of the half-wave oscillator 11 to improve the gain of the antenna unit 10, and generating an obvious resonance frequency point in a state that the distance range between the two ends of the half-wave oscillator 11 is greater than or equal to λ/128 and less than or equal to λ/6 and is close to the reference ground.

In particular, in this alternative embodiment, the number of the feeding lines is two corresponding to the number of the feeding points 110, wherein the two feeding lines 13 are electrically connected to the feeding point 110 of the half-wave oscillator 11 and the half-wave oscillator 11 respectively in a state that one end of each of the two feeding lines 13 is electrically connected to the feeding end 111 of the two coupling sections 112, so that when the other ends of the two feeding lines 13 are electrically connected to the local oscillator circuit and/or the mixer circuit, the half-wave oscillator 11 is fed at the two feeding points 110 through the electrical connection between the feeding point 110 and the half-wave oscillator 11 of the feeding lines 13.

It is worth mentioning that in this alternative embodiment, the two feeder lines 13 sequentially extend from the two feeder points 110 of the half-wave oscillator 11 in directions toward and towards the reference ground 12, so that the two feeder lines 13 have feeder sections 131 close to each other within a distance range smaller than the distance between the two feeder points 110 of the half-wave oscillator 11, thereby being beneficial to reducing the loss caused by mutual coupling between the two feeder lines 13 and correspondingly ensuring the gain and the resonance stability of the antenna unit 10.

In particular, in this alternative embodiment, one end of the feed line 13, which is connected to the local oscillator signal, is fixed to the circuit substrate 14, wherein the feed line 13 penetrates the reference ground 12 through the isolation hole 121 to form the isolation gap 1211 with the reference ground 12, and is electrically isolated from the reference ground 12 in terms of physical structure, so that when the feed line 13 is connected to the local oscillator circuit and/or the mixer circuit, the feed line 13 is electrically connected to the half-wave oscillator 11 at the feed point 110, and the half-wave oscillator 11 is fed to the half-wave oscillator 11 at the feed point 110 in a state where the half-wave oscillator 11 is disposed at a distance from the reference ground 12.

It should be noted that, in this alternative embodiment, two ends of the two feeder lines 13, which are connected to the local oscillator signal, extend in a bending manner in the direction away from each other in the corresponding feeder section 131, specifically, extend from the feeder section 131 first in a reverse direction and toward the reference ground 12, then extend toward the reference ground 12, and in a state where the feeder lines 13 are designed in a columnar strip form, a section extending toward the reference ground 12 is designed to be thicker than the feeder section 131.

Corresponding to fig. 4, on the basis of the structure of the antenna unit 10 illustrated in fig. 3, one ends of the two feeding lines 13, which are connected to the local oscillator signal, are fixed to the circuit substrate 14, wherein the reference ground 12 is provided with two isolation holes 121, wherein the two feeding lines 13 penetrate through the reference ground 12 through the two isolation holes 121, respectively, wherein the two feeding lines 13 are electrically coupled to the local oscillator circuit, respectively, and wherein the frequency mixing loop and the frequency selecting unit 20 are electrically coupled between one of the feeding lines 13 and the local oscillator circuit.

With further reference to fig. 5 to 13 of the drawings of the specification of the present invention, a partial equivalent circuit structure of the interference-free half-wave folded antenna microwave detecting device according to various embodiments of the present invention is disclosed, specifically as shown in fig. 5, wherein the frequency selecting unit 20 includes an equivalent capacitor 21 and a pair of ground equivalent inductors 22, wherein in a state where the antenna unit 10 is fed and connected to the local oscillator circuit and/or the frequency mixing loop through the feeder line 13, one pole of the equivalent capacitor 21 is fed and connected to the feeder line 13, and the other pole of the equivalent capacitor 21 is fed and connected to the local oscillator circuit and/or the frequency mixing loop, so as to form a feeding path between the feeder line 13 and the local oscillator circuit and/or the frequency mixing loop to form a state where the antenna unit 10 is fed by the local oscillator circuit and/or the frequency mixing loop through the feeder line and the feeding path, the equivalent inductance to ground 22 is led out from the feed path in a state of being electrically connected to the other electrode of the equivalent capacitance 21 to form a frequency selection network with high-pass characteristic with the equivalent capacitance 21, so as to reduce interference of electromagnetic radiation in an environment different from an operating frequency band of the anti-interference half-wave folded antenna microwave detection device on the anti-interference half-wave folded antenna microwave detection device.

In particular, the frequency selecting unit 20 can suppress a high-frequency band signal of higher harmonic radiation generated by the local oscillator circuit and/or the frequency mixing loop, so as to suppress interference of a signal different from an operating frequency band of the half-wave folded-back antenna microwave detection device on the anti-interference half-wave folded-back antenna microwave detection device, and improve detection accuracy of the anti-interference half-wave folded-back antenna microwave detection device.

It should be noted that the equivalent capacitor 21 and the equivalent inductance to ground 22 are components respectively having a capacitance characteristic and an inductance characteristic under the high-frequency current corresponding to the frequency of the local oscillator signal, that is, the equivalent capacitor 21 is a component having a capacitance characteristic and being equivalent to a capacitance under the high-frequency current corresponding to the frequency of the local oscillator signal, such as a microstrip line or a high-frequency capacitor spaced from each other, and the equivalent inductance to ground 22 is a component having an inductance characteristic and being equivalent to an inductance under the high-frequency current corresponding to the frequency of the local oscillator signal, such as an inductance, a microstrip line or a resistance, that is, a conductor having a certain resistance, which is not limited in this respect.

In particular, wherein the equivalent capacitor 22 can be equivalently formed by at least two capacitors based on the connection relationship of series and/or parallel, further referring to fig. 6 of the drawings of the specification of the present invention, a partial equivalent circuit structure of the microwave detecting device of the tamper-resistant half-wave folded antenna according to an embodiment of the present invention is disclosed, in which the equivalent capacitor 21 is equivalently formed by two capacitors 21A in series, and further referring to fig. 7 of the drawings of the specification of the present invention, in which the equivalent capacitor 21 is equivalently formed by two capacitors 21A in parallel in this embodiment shown in fig. 7, wherein the equivalent inductor 22 to ground can be equivalently formed by at least two inductors based on the connection relationship of series, further referring to fig. 8, in which the equivalent inductor 22 to ground is equivalently formed by two inductors 22A in parallel in this embodiment shown in fig. 8.

It should be noted that, in some embodiments of the present invention, the equivalent capacitor 21 is a circuit structure with a capacitive characteristic equivalently formed on the corresponding circuit board based on the coupling between the conductors with gaps, such as a distributed capacitor formed by coupling between the conductors with gaps disposed on both sides of the corresponding circuit board, or a microstrip capacitor formed by coupling between microstrip lines with gaps disposed on the same side of the corresponding circuit board. It is also worth mentioning that, in some embodiments of the present invention, the ground equivalent inductor 22 is disposed in a microstrip line.

With further reference to fig. 9A of the drawings of the specification of the present invention, a partial equivalent circuit structure of the tamper resistant half-wave folded antenna microwave detecting device according to another embodiment of the present invention is disclosed, which is different from fig. 5, in this embodiment shown in fig. 9A, wherein the frequency selecting unit 20 further includes a transmission equivalent inductor 23, wherein the transmission equivalent inductor 23 is disposed in the feeding path in series with the equivalent capacitor 21, wherein the transmission equivalent inductor 23 is disposed in the feeding path between the ground equivalent inductor 22 and the equivalent capacitor 21 to suppress high frequency signals above the operating frequency band of the tamper resistant half-wave folded antenna microwave detecting device, so as to further reduce interference of electromagnetic radiation in the environment different from the operating frequency band of the tamper resistant half-wave folded antenna microwave detecting device on the tamper resistant half-wave folded antenna microwave detecting device, and the detection accuracy of the anti-interference half-wave folded antenna microwave detection device is further improved.

In particular, with further reference to fig. 9B of the drawings of the specification of the present invention, unlike fig. 9A, wherein the transmission equivalent inductor 23 is disposed on the feeding path between the ground equivalent inductor 22 and the local oscillator circuit and/or the mixer circuit, that is, the specific location where the transmission equivalent inductor 23 is disposed on the feeding path is not limited as long as the location limitation that "the transmission equivalent inductor 23 is disposed on the feeding path in a state of being connected in series with the equivalent capacitor 21" is satisfied.

With further reference to fig. 10 of the drawings of the specification of the present invention, a partial equivalent circuit structure of the anti-jamming half-wave folded antenna microwave detection device according to another embodiment of the present invention is disclosed, which is different from fig. 5. in this embodiment shown in fig. 10, the number of the frequency selecting units 20 is two, that is, by providing a plurality of frequency selecting units 20, interference signals lower than the working frequency band of the anti-jamming half-wave folded antenna microwave detection device are filtered step by step, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

In particular, the impedance between the antenna unit 10 and the feeding circuit and/or the mixing loop is matched based on appropriate numerical selection of components of the frequency selection unit, that is, the equivalent capacitor 21, the equivalent inductance to ground 22 and the equivalent inductance to transmission 23, so that the microwave detection apparatus of the anti-interference half-wave folded antenna operates in an optimal state.

With further reference to fig. 11 of the drawings accompanying the present specification, a partial equivalent circuit structure of the tamper resistant half-wave folded antenna microwave detection device according to another embodiment of the present invention is disclosed, which is different from fig. 10, in this embodiment shown in fig. 11, wherein the tamper resistant half-wave folded antenna microwave detection device further includes a pair-ground pre-selection inductor 200, wherein the pair-ground pre-selection inductor 200 is led out from the feeding path in an electrically connected state with the feeding line 13 to pre-select and filter a low-frequency band signal, so as to further improve the detection accuracy of the tamper resistant half-wave folded antenna microwave detection device.

It should be noted that the ground preselection inductor 200 may also be disposed in a partial equivalent circuit structure of the anti-jamming half-wave folded antenna microwave detection device shown in any one of fig. 5 to 9, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

With further reference to fig. 12 of the drawings of the specification of the present invention, a partial equivalent circuit structure of the tamper-resistant half-wave folded antenna microwave detection device according to another embodiment of the present invention is disclosed, which is different from fig. 11, in this embodiment shown in fig. 12, the tamper-resistant half-wave folded antenna microwave detection device further includes at least one series resonant network led out from the feed path, where the series resonant network includes a first equivalent capacitor 211 led out from the feed path, and a first equivalent inductance 221 connected in series with the first equivalent capacitor 211, so as to filter out an interference signal at a specific frequency point, and further improve the detection accuracy of the tamper-resistant half-wave folded antenna microwave detection device.

Similarly, the series resonant network shown in fig. 12 may also be disposed in a partial equivalent circuit structure of the anti-jamming half-wave folded antenna microwave detection device shown in any one of fig. 5 to 10, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

With further reference to fig. 13 of the drawings of the specification of the present invention, a partial equivalent circuit structure of the tamper-resistant half-wave folded antenna microwave detection device according to another embodiment of the present invention is disclosed, which is different from fig. 12. in this embodiment shown in fig. 13, the tamper-resistant half-wave folded antenna microwave detection device further includes at least one parallel resonant network disposed in the feed path, wherein the parallel resonant network includes a second equivalent capacitor 212 disposed in the feed path in series with the equivalent capacitor 21, and a second equivalent inductor 222 connected in parallel with the second equivalent capacitor 212, so as to block interference signals of specific frequency points, thereby further improving the detection accuracy of the tamper-resistant half-wave folded antenna microwave detection device.

Similarly, the parallel resonant network shown in fig. 13 may also be disposed in a partial equivalent circuit structure of the anti-jamming half-wave folded antenna microwave detection device shown in any one of fig. 5 to 11, so as to further improve the detection accuracy of the anti-jamming half-wave folded antenna microwave detection device.

That is to say, the anti-interference half-wave folded antenna microwave detection device has an anti-interference frequency selection characteristic for the local oscillator signal and/or the feedback signal in a state of being fed and connected to the local oscillator circuit and/or the mixing loop, and based on the optimized structural design of the antenna unit, the anti-interference half-wave folded antenna microwave detection device has a longer detection distance, a larger detection sector angle and a more stable anti-interference capability, so that the anti-interference half-wave folded antenna microwave detection device can realize precise microwave detection in a large area and a large area.

It will be appreciated by persons skilled in the art that the embodiments of the utility model described above and shown in the drawings are given by way of example only and are not limiting of the utility model. The objects of the utility model have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. An anti-interference half-wave folded antenna microwave detection device, it has to corresponding local oscillator signal and/or anti-interference frequency selection characteristic of repayment signal in the state of being connected in corresponding local oscillator circuit and/or mixing circuit by the feed, its characterized in that includes:

2. The tamper resistant half-wave folded antenna microwave detection device of claim 1, wherein the equivalent capacitance is equivalently formed by at least two capacitances based on a series and/or parallel connection relationship.

3. The tamper resistant, half-wave folded antenna microwave detection device of claim 1, wherein the equivalent capacitance is a circuit structure with capacitive characteristics equivalently formed on the corresponding circuit board based on coupling between conductors with gaps.

4. The tamper resistant half-wave folded antenna microwave detection device of claim 1 wherein the equivalent inductance to ground is equivalently formed by at least two inductances based on a series connection relationship.

5. The tamper resistant half-wave folded antenna microwave detection device of claim 1 wherein the equivalent inductance to ground is provided in a microstrip line configuration.

6. The tamper resistant half-wave folded antenna microwave detection device of claim 1, wherein the frequency selection unit further comprises a transmission equivalent inductance, wherein the transmission equivalent inductance is disposed in the feed path in series with the equivalent capacitance.

7. The tamper resistant half-wave folded antenna microwave detection device of any of claims 1 to 6, wherein the tamper resistant half-wave folded antenna microwave detection device further comprises a pair ground pre-selection inductor, wherein the pair ground pre-selection inductor is routed from the feed path in electrical connection with the feed line.

8. The tamper resistant half-wave folded antenna microwave detection device of any of claims 1 to 6, wherein the tamper resistant half-wave folded antenna microwave detection device further comprises at least a series resonant network leading from the feed path, wherein the series resonant network comprises a first equivalent capacitance leading from the feed path and a first equivalent inductance to ground in series with the first equivalent capacitance.

9. The tamper resistant half-wave folded antenna microwave detection device of any of claims 1 to 6, wherein the tamper resistant half-wave folded antenna microwave detection device further comprises at least one parallel resonant network disposed at the feed path, wherein the parallel resonant network comprises a second equivalent capacitor disposed at the feed path in series with the equivalent capacitor, and a second equivalent inductor in parallel with the second equivalent capacitor.

10. An anti-interference half-wave folded antenna microwave detection device, it has to corresponding local oscillator signal and/or anti-interference frequency selection characteristic of repayment signal in the state of being connected in corresponding local oscillator circuit and/or mixing circuit by the feed, its characterized in that includes:

11. The tamper resistant half-wave folded antenna microwave detection device of claim 10, wherein the equivalent capacitance is equivalently formed by at least two capacitances based on a series and/or parallel connection relationship.

12. The tamper resistant, half-wave folded antenna microwave detection device of claim 10 wherein the equivalent capacitance is a capacitive circuit structure equivalently formed on the respective circuit board based on coupling between conductors having gaps.

13. The tamper resistant half-wave folded antenna microwave detection device of claim 10 wherein the equivalent inductance to ground is equivalently formed by at least two inductances based on a series connection relationship.

14. The tamper resistant half-wave folded antenna microwave detection device of claim 10 wherein the equivalent inductance to ground is provided in a microstrip line configuration.

15. The tamper resistant half-wave folded antenna microwave detection device of claim 10 wherein the frequency selection unit further comprises a transmission equivalent inductance, wherein the transmission equivalent inductance is disposed in the feed path in series with the equivalent capacitance.

16. The tamper resistant half-wave folded antenna microwave detection device of any of claims 10 to 15, wherein the tamper resistant half-wave folded antenna microwave detection device further comprises a ground pre-selection inductor, wherein the ground pre-selection inductor is routed from the feed path in electrical connection with the feed line.

17. A tamper resistant half-wave folded antenna microwave detection device according to any of claims 10 to 15 and wherein said tamper resistant half-wave folded antenna microwave detection device further comprises at least a series resonant network extending from said feed path, wherein said series resonant network comprises a first equivalent capacitance extending from said feed path and a first equivalent inductance to ground in series with said first equivalent capacitance.

18. The tamper resistant half-wave folded antenna microwave detection device of any of claims 10 to 15, wherein the tamper resistant half-wave folded antenna microwave detection device further comprises at least one parallel resonant network disposed in the feed path, wherein the parallel resonant network comprises a second equivalent capacitor disposed in the feed path in series with the equivalent capacitor, and a second equivalent inductor in parallel with the second equivalent capacitor.