Waveguide type terahertz wave Doppler interference measurement structure and measurement method

Abstract

The invention relates to the technical field of interference measurement, and provides a waveguide type terahertz wave Doppler interference measurement structure, which comprises a terahertz wave waveguide used for constraining terahertz waves and realizing two-way transmission of the terahertz waves; a terahertz wave waveguide adapter; provided is a terahertz wave waveguide probe. The measurement method comprises the following steps: a terahertz wave Doppler interference measurement host emits terahertz waves, and the terahertz waves are transmitted to a terahertz wave waveguide probe through a flexible terahertz wave waveguide; the terahertz wave waveguide probe transmits terahertz waves to a measured target, and the terahertz waves are vertically reflected by the measured target; the terahertz wave reflected by the measured target is collected by the terahertz wave waveguide probe and then is transmitted into the terahertz wave Doppler interference measurement host along the flexible terahertz wave waveguide; the terahertz wave Doppler interference measurement host converts terahertz waves into terahertz interference signals and outputs the terahertz interference signals to the oscilloscope for acquisition and storage; and analyzing and processing the terahertz interference signal.

Description

Technical Field

[0001] The present invention relates to the technical field of interferometry, and particularly relates to a waveguide-type terahertz wave Doppler interferometry structure and a measurement method. Background Art

[0002] The terahertz wave Doppler interferometry technology is a technology that measures the displacement or velocity history of a target to be measured by using terahertz waves based on the Doppler effect. The terahertz waves used in this technology have good penetration properties for non-polar materials (such as explosives) and substances such as flame soot, etc., so it is applicable to non-invasive measurements of hidden targets in environments such as internal ballistic parameters of artillery and gunpowder explosions.

[0003] In current terahertz wave Doppler interferometry systems, the free space propagation mode is generally used to transmit terahertz waves. The specific method is generally to emit the terahertz waves generated by a terahertz wave source into free space through a horn antenna. Since the diffraction effect of terahertz waves is relatively strong, generally a terahertz lens or a curved mirror is also required to expand and collimate the terahertz waves, and finally the terahertz waves are guided to the target to be measured through the free space propagation mode. When necessary, a mirror is also required to deflect the transmission direction of the terahertz waves. The terahertz waves reflected by the target to be measured are also transmitted back to the terahertz wave Doppler interferometry system through free space.

[0004] In terahertz wave Doppler interferometry, the problems brought by using free space to transmit terahertz waves are: the spot diameter of terahertz waves in the free space transmission range is relatively large; the propagation direction of terahertz waves is difficult to continuously adjust; at the target to be measured, a terahertz focusing lens is also required to focus the terahertz waves on the target, and the lateral size of the terahertz focusing lens is relatively large, and the longitudinal distance required by it (between the focusing lens and the target to be measured) is also relatively large. The above points all make it difficult for the free space transmission type terahertz wave Doppler interferometry to be used for measuring targets in a narrow space. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a waveguide-type terahertz wave Doppler interferometry structure and a measurement method, which can realize the measurement of targets in a narrow space.

[0006] According to the first aspect of the present invention, a waveguide-type terahertz wave Doppler interferometry structure is provided, including a terahertz wave Doppler interferometry host, and further including:

[0007] A terahertz wave waveguide, which is used to confine terahertz waves and realize the bidirectional transmission of the terahertz waves;

[0008] Terahertz waveguide adapter, the first end of the terahertz waveguide adapter is connected to the transmitting port of the terahertz wave Doppler interferometry host, and the second end of the terahertz waveguide adapter is connected to the first end of the terahertz waveguide;

[0009] Terahertz waveguide probe, the first end of the terahertz waveguide probe is connected to the second end of the terahertz waveguide, and the second end of the terahertz waveguide probe faces the target to be measured.

[0010] Furthermore, the terahertz waveguide is a flexible hollow tubular structure, and the cross-section of the terahertz waveguide is circular.

[0011] Furthermore, a first conversion cavity is formed inside the terahertz waveguide adapter and runs through transversely. The cross-section formed by the first conversion cavity at the first end of the terahertz waveguide adapter is rectangular, and the cross-section formed by the first conversion cavity at the second end of the terahertz waveguide adapter is circular.

[0012] Furthermore, the two ends of the first conversion cavity have a smooth transition.

[0013] Furthermore, a first annular gripper and a first locking nut are provided between the terahertz waveguide adapter and the terahertz waveguide;

[0014] The first end of the first annular gripper is fixedly connected and communicated with the first end of the terahertz waveguide. The second end of the first annular gripper is in contact with the inner wall of the first conversion cavity. The first locking nut is sleeved outside the first annular gripper and is threadedly connected to the terahertz waveguide adapter. The first locking nut makes the first annular gripper press against the inner wall of the first conversion cavity.

[0015] Furthermore, a second conversion cavity is formed inside the terahertz waveguide probe and runs through transversely. The second conversion cavity is a horn-shaped structure, and the inner diameter of the second conversion cavity gradually increases from the first end of the terahertz waveguide probe to the second end of the terahertz waveguide probe.

[0016] Furthermore, the two ends of the second conversion cavity have a smooth transition.

[0017] Furthermore, a second annular gripper and a second locking nut are provided between the terahertz waveguide probe and the terahertz waveguide;

[0018] The first end of the second annular clamping jaw is fixedly connected and communicated with the second end of the terahertz waveguide. The second end of the second annular clamping jaw contacts the inner wall of the first end of the terahertz waveguide probe. The second locking nut is sleeved on the outside of the second annular clamping jaw and is threadedly connected to the terahertz waveguide probe. The second locking nut makes the second annular clamping jaw tightly press against the inner wall of the first end of the terahertz waveguide probe.

[0019] According to the second aspect of the present invention, a measurement method is provided, including the following steps:

[0020] S1. The terahertz wave Doppler interference measurement host emits the terahertz wave, and the terahertz wave is transmitted to the terahertz waveguide probe through the flexible terahertz waveguide;

[0021] S2. The terahertz waveguide probe emits the terahertz wave to the measured target and is vertically reflected by it;

[0022] S3. The terahertz wave reflected by the measured target is collected by the terahertz waveguide probe and then transmitted to the inside of the terahertz wave Doppler interference measurement host along the flexible terahertz waveguide;

[0023] S4. The terahertz wave Doppler interference measurement host converts the terahertz wave into a terahertz interference signal and outputs it to an oscilloscope for acquisition and storage;

[0024] S5. Analyze and process the terahertz interference signal.

[0025] Advantages of the present invention: The waveguide-type terahertz wave Doppler interference measurement structure and measurement method provided by the present invention use a terahertz waveguide to transmit the terahertz wave to the measured target, use a terahertz waveguide probe to collect and transmit the terahertz wave reflected by the measured target. The terahertz waveguide used has the characteristics of a smaller lateral dimension of the device and a continuously adjustable propagation direction of the terahertz wave, so as to realize the measurement of the target in a narrow space. Description of the Drawings

[0026] Figure 1 is a schematic flow structure diagram of the present invention;

[0027] Figure 2 is a schematic three-dimensional structure diagram of the present invention;

[0028] Figure 3 is a schematic internal sectional structure diagram of the present invention;

[0029] Figure 4 is Figure 3 an enlarged structure diagram of part A in

[0030] Figure 5 is Figure 3 The enlarged structural schematic diagram of part B in

[0031] Reference numerals: 10 - Terahertz wave Doppler interferometry mainframe, 20 - Terahertz wave waveguide, 30 - Terahertz wave waveguide adapter, 31 - First conversion cavity, 32 - First gripper, 33 - First locking nut, 40 - Terahertz wave waveguide probe, 41 - Second conversion cavity, 42 - Second annular gripper, 43 - Second locking nut, 50 - Measured target. Specific embodiments

[0032] To make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

[0033] In this application, unless otherwise clearly specified and limited, the terms "connection" and "fixation" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "horizontal", "top", "bottom", "upper", "lower", "inner" and "outer" etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0035] In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. In the description of the present invention, "a plurality" means more than two unless otherwise clearly and specifically defined.

[0036] As Figures 1-5 shown, the present invention provides a waveguide-type terahertz wave Doppler interferometry structure, including a terahertz wave Doppler interferometry mainframe, which is used to emit terahertz waves of a certain frequency, collect the terahertz waves reflected by the measured target, and generate interference signals. The cross-section of the emission port of the terahertz wave Doppler interferometry mainframe is rectangular. The above contents are all prior arts and will not be elaborated on the specific structure here. The present invention also includes a terahertz wave waveguide, a terahertz wave waveguide adapter and a terahertz wave waveguide probe.

[0037] The terahertz waveguide is used to confine terahertz waves and achieve bidirectional transmission of terahertz waves. When the terahertz waveguide is bent to a certain extent, the terahertz waves can be well confined within the flexible terahertz waveguide without leakage or loss.

[0038] The first end of the terahertz waveguide adapter is connected to the transmitting port of the terahertz wave Doppler interferometry host, and the second end of the terahertz waveguide adapter is connected to the first end of the terahertz waveguide. The terahertz waveguide adapter is mainly used for the propagation mode conversion of terahertz waves, so that the terahertz waves emitted from the transmitting port of the terahertz wave Doppler interferometry host are converted from the propagation mode supported by the (rectangular) transmitting port to the propagation mode supported by the terahertz waveguide, and the terahertz waves that are reflected back from the target to be measured and propagate within the terahertz waveguide are converted back to the propagation mode supported by the (rectangular) transmitting port of the terahertz wave Doppler interferometry host.

[0039] The first end of the terahertz waveguide probe is connected to the second end of the terahertz waveguide, and the second end of the terahertz waveguide probe faces the target to be measured. The terahertz waveguide probe is used to convert the terahertz waves propagating in the terahertz waveguide into terahertz waves with a larger propagation surface and emit them to the target to be measured, and collect the terahertz waves reflected by the target to be measured and convert them into the propagation mode supported within the terahertz waveguide. It should be noted that the existing terahertz waveguide probes currently do not support the conversion of the propagation mode.

[0040] The specific working process of the present invention is as follows:

[0041] First, the staff installs the terahertz waveguide adapter on the transmitting port of the terahertz wave Doppler interferometry host, installs the terahertz waveguide probe in front of the target to be measured, and connects the two ends of the flexible terahertz waveguide to the terahertz waveguide adapter and the terahertz waveguide probe respectively.

[0042] Then, the staff controls the terahertz wave Doppler interferometry host to emit terahertz waves. The terahertz waves are transmitted through the terahertz waveguide to the terahertz waveguide probe, and the terahertz waveguide probe emits the terahertz waves to the target to be measured and is vertically reflected by it.

[0043] Next, the terahertz waves reflected by the target to be measured are collected by the terahertz waveguide probe and transmitted along the terahertz waveguide into the terahertz wave Doppler interferometry host. The terahertz wave Doppler interferometry host converts the terahertz waves into terahertz interference signals and outputs them to the oscilloscope for acquisition and storage.

[0044] Finally, the computer analyzes and processes the terahertz interference signals, and measures the terahertz Doppler frequency shift and the speed of the target to be measured obtained through the analysis, and the measurement is completed.

[0045] In one embodiment, the terahertz waveguide is a flexible hollow tubular structure, and the cross-section of the terahertz waveguide is circular. In this way, the terahertz waveguide can be bent at will to adapt to more environments.

[0046] In one embodiment, a first conversion cavity penetrating transversely is formed inside the terahertz waveguide adapter. The cross-section formed at the first end of the terahertz waveguide adapter of the first conversion cavity is rectangular to adapt to the emission port of the terahertz wave Doppler interferometry host. The cross-section formed at the second end of the terahertz waveguide adapter of the first conversion cavity is circular to adapt to the terahertz waveguide.

[0047] The waveguide converter adopts the design principle of adiabatic gradual approximation to gradually change the cross-section of the first conversion cavity from rectangular to circular, so as to achieve high-efficiency conversion of terahertz waves between the TE10 mode of the rectangular waveguide and the TE11 mode of the circular waveguide.

[0048] In one embodiment, the two ends of the first conversion cavity are smoothly transitioned so that the transmission of terahertz waves is more orderly and stable.

[0049] In one embodiment, a first annular clamping jaw and a first locking nut are provided between the terahertz waveguide adapter and the terahertz waveguide.

[0050] The first end of the first annular clamping jaw is fixedly connected and communicated with the first end of the terahertz waveguide, and the second end of the first annular clamping jaw contacts the inner wall of the first conversion cavity. The first locking nut is sleeved outside the first annular clamping jaw and is threadedly connected with the terahertz waveguide adapter, and the first locking nut makes the first annular clamping jaw press against the inner wall of the first conversion cavity.

[0051] The outer wall of the terahertz waveguide adapter has an external thread. After the first locking nut is threadedly connected with the terahertz waveguide adapter, the first annular clamping jaw will press against the inner wall of the first conversion cavity, so that the waveguide converter is connected to the terahertz wave flexible waveguide together.

[0052] This design realizes the rapid docking of the waveguide converter and the terahertz wave flexible waveguide, and has the advantages of reliable connection and not easy to fall off.

[0053] In one embodiment, a second conversion cavity penetrating transversely is formed inside the terahertz waveguide probe. The second conversion cavity is a horn-shaped structure, and the inner diameter of the second conversion cavity gradually increases from the first end to the second end of the terahertz waveguide probe.

[0054] The terahertz waveguide probe also adopts the design principle of adiabatic gradient approximation. The inner diameter of the second conversion cavity gradually increases from the first end to the second end of the terahertz waveguide probe, so as to convert the terahertz wave into a terahertz wave with a larger propagation surface and emit it into free space.

[0055] In one embodiment, the two ends of the second conversion cavity are smoothly transitioned so that the transmission of the terahertz wave is more orderly and stable.

[0056] In one embodiment, a second annular clamp and a second locking nut are provided between the terahertz waveguide probe and the terahertz waveguide.

[0057] The first end of the second annular clamp is fixedly connected and communicated with the second end of the terahertz waveguide, and the second end of the second annular clamp contacts the inner wall of the first end of the terahertz waveguide probe. The second locking nut is sleeved on the outside of the second annular clamp and is threadedly connected with the terahertz waveguide probe. The second locking nut makes the second annular clamp press against the inner wall of the first end of the terahertz waveguide probe.

[0058] The outer wall of the terahertz waveguide probe has an external thread. After the second locking nut is threadedly connected with the terahertz waveguide adapter, the second annular clamp will press against the inner wall of the second conversion cavity, so that the terahertz waveguide probe is flexibly connected to the terahertz waveguide.

[0059] This design realizes the rapid docking of the terahertz waveguide probe and the terahertz flexible waveguide, and has the advantages of reliable connection and not easy to fall off.

[0060] A measurement method includes the following steps:

[0061] S1. The staff controls the terahertz wave Doppler interference measurement host to emit terahertz waves, and the terahertz waves are transmitted to the terahertz waveguide probe through the terahertz waveguide.

[0062] S2. The terahertz waveguide probe emits the terahertz wave to the measured target and is vertically reflected by it.

[0063] S3. The terahertz wave reflected by the measured target is collected by the terahertz waveguide probe and transmitted to the terahertz wave Doppler interference measurement host along the terahertz waveguide.

[0064] S4. The terahertz wave Doppler interference measurement host converts the terahertz wave into a terahertz interference signal and outputs it to the oscilloscope for acquisition and storage.

[0065] S5. Finally, the computer analyzes and processes the terahertz interference signal, and obtains the terahertz Doppler frequency shift and the speed of the measured target through analysis, and the measurement is completed.

[0066] The foregoing has shown and described the basic principles, main features and advantages of the present invention. For a person skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, in whatever aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes that fall within the meaning and scope of the equivalent elements of the claims in the present invention.

[0067] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A waveguide terahertz wave Doppler interferometry structure, comprising a terahertz wave Doppler interferometry host, characterized in that: Also includes: A terahertz wave guide, which is used to confine the terahertz wave and realize the bidirectional transmission of the terahertz wave; A terahertz wave waveguide adapter, wherein a first end of the terahertz wave waveguide adapter is connected to a transmitting port of the terahertz wave Doppler interferometry host, and a second end of the terahertz wave waveguide adapter is connected to a first end of the terahertz wave waveguide; A terahertz wave waveguide probe, wherein a first end of the terahertz wave waveguide probe is connected to a second end of the terahertz wave waveguide, and the second end of the terahertz wave waveguide probe faces a measured object.

2. The waveguide terahertz wave Doppler interferometry measurement structure according to claim 1, characterized in that: The terahertz wave guide is a flexible hollow tubular structure, and the cross section of the terahertz wave guide is circular.

3. The waveguide terahertz wave Doppler interferometry structure according to claim 2, characterized in that: A first conversion cavity is formed inside the terahertz waveguide adapter and penetrates in the transverse direction. The cross section of the first conversion cavity formed at the first end of the terahertz waveguide adapter is rectangular, and the cross section of the first conversion cavity formed at the second end of the terahertz waveguide adapter is circular.

4. The waveguide terahertz wave Doppler interferometry structure according to claim 3, characterized in that: The first conversion cavity has a smooth transition between the two ends.

5. The waveguide terahertz wave Doppler interferometry structure according to claim 4, characterized in that: A first annular claw and a first locking nut are provided between the terahertz wave guide adapter and the terahertz wave guide; The first end of the first annular claw is fixedly connected and communicated with the first end of the terahertz wave guide, the second end of the first annular claw is in contact with the inner wall of the first conversion cavity, the first locking nut is sleeved on the outer side of the first annular claw and is threadedly connected to the terahertz wave guide adapter, and the first locking nut enables the first annular claw to press against the inner wall of the first conversion cavity.

6. The waveguide terahertz wave Doppler interferometry structure according to claim 2, characterized in that: A second conversion cavity is formed inside the terahertz waveguide probe and penetrates in the transverse direction. The second conversion cavity is a horn-shaped structure, and the inner diameter of the second conversion cavity gradually increases from the first end of the terahertz waveguide probe to the second end of the terahertz waveguide probe.

7. The waveguide terahertz wave Doppler interferometry structure according to claim 6, characterized in that: The two ends of the second conversion cavity have a smooth transition.

8. The waveguide terahertz wave Doppler interferometry structure according to claim 7, characterized in that: A second annular claw and a second locking nut are provided between the terahertz wave waveguide probe and the terahertz wave waveguide; The first end of the second annular claw is fixedly connected and communicated with the second end of the terahertz wave guide, the second end of the second annular claw contacts the inner wall of the first end of the terahertz wave guide probe, the second locking nut is sleeved on the outer side of the second annular claw and is threadedly connected with the terahertz wave guide probe, and the second locking nut enables the second annular claw to press against the inner wall of the first end of the terahertz wave guide probe.

9. A measurement method, applied to the waveguide terahertz wave Doppler interferometry measurement structure according to claim 2, characterized in that: The following steps are involved: S1, the terahertz wave Doppler interferometry host emits the terahertz wave, and the terahertz wave is transmitted to the terahertz wave waveguide probe through the flexible terahertz wave waveguide; S2, the terahertz wave waveguide probe transmits the terahertz wave to the measured object, and is vertically reflected by the object; S3, the terahertz wave reflected by the measured target is collected by the terahertz wave waveguide probe and then transmitted along the flexible terahertz wave waveguide to the terahertz wave Doppler interferometry host; S4, the terahertz wave Doppler interferometry host converts the terahertz wave into a terahertz interference signal and outputs it to an oscilloscope for collection and storage; S5. Analyze and process the terahertz interference signal.

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