Closed metal shell internal structure monitoring system and monitoring method

Abstract

The present invention discloses a closed metal shell internal structure monitoring system, including a transmitting antenna extending into the metal shell for transmitting electromagnetic waves into the closed shell; a wavefront modulator installed inside the metal shell, which is connected to a circuit board and a computer for modulating the electromagnetic waves in the metal shell, and the wavefront modulator includes a plurality of modulation units, and each modulation unit can be controlled to be turned on or off by a computer and a circuit board; a receiving antenna for receiving electromagnetic waves in the metal shell, and a network analyzer electrically connected to the transmitting antenna and the receiving antenna, respectively. The present invention also provides a monitoring method for the closed metal shell internal structure monitoring system. The present invention can judge the changes in different parts of the internal structure of the closed metal shell by the changes in the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna, thereby realizing real-time monitoring of the internal structure of the closed metal shell.

Description

Technical Field

[0001] The invention relates to a closed metal shell internal structure monitoring system and a monitoring method thereof, which are used for monitoring the structural changes inside the closed metal shell. Background Art

[0002] Sealed metal shells are widely used in various industrial designs. For example, most electronic equipment uses metal shells as outer shells to enhance their electromagnetic compatibility; some special materials need to be placed in sealed metal shells to maintain the performance of the materials; shielded rooms, microwave darkrooms, etc. are all designed with closed metal shell structures to reduce the impact of external electromagnetic signals on indoor testing.

[0003] Some metal shells are difficult to disassemble or are not allowed to be disassembled, but their internal structures need to be monitored to promptly detect structural changes such as parts falling off, parts moving and deforming, and parts oxidizing, so as to facilitate maintenance at the first time, shorten the maintenance cycle, and ensure equipment operation. Since the inside of the shell is a dark environment, existing monitoring equipment usually finds it difficult to monitor the internal structure of a closed metal shell. Summary of the invention

[0004] In order to solve the above technical problems, the first object of the present invention is to provide a closed metal shell internal structure monitoring system, which can realize real-time monitoring of the internal structure of the closed metal shell.

[0005] To achieve the above purpose, the technical solution of the present invention is as follows:

[0006] A closed metal shell internal structure monitoring system comprises a transmitting antenna extending into the metal shell and used for transmitting electromagnetic waves into the metal shell; a wavefront modulator installed inside the metal shell, which is connected to a circuit board and a computer and is used for modulating the electromagnetic waves in the metal shell, the wavefront modulator comprises a plurality of modulation units, each modulation unit can be controlled to be turned on or off by a computer and a circuit board; a receiving antenna for receiving electromagnetic waves in the metal shell, and a network analyzer electrically connected to the transmitting antenna and the receiving antenna respectively.

[0007] By adopting the above technical solution, the transmission amplitude between the transmitting antenna and the receiving antenna is measured regularly using a network analyzer and compared with the standard data at the initial assembly of the equipment. This can determine whether the internal structure of the sealed metal shell has changed. By controlling the on and off of each modulation unit of the wavefront modulator through the circuit board, different electromagnetic wave beams can be formed to scan different parts of the internal structure of the metal shell.

[0008] Preferably, the modulation unit includes a dielectric substrate, the front and back surfaces of the dielectric substrate are both paved with microstrip metal sheets, and at least two modulation circuits are formed on the front surface. Adjacent modulation circuits are connected through diodes, and each diode can be controlled to be turned on or off through a computer and a circuit board. With the above structure, the modulation circuit can be lengthened or shortened by turning on or off the diode. The two states can reflect or absorb electromagnetic waves in different frequency bands, thereby achieving the purpose of modulating the direction and amplitude of the electromagnetic wave beam.

[0009] To facilitate the on-off control of the diode, the wavefront modulator is connected to the circuit board via a cable. Two metal through holes are provided on the dielectric substrate of each modulation unit at the position corresponding to the diode, and are connected to the interface of the cable via a wire.

[0010] Preferably, the transmitting antenna extends from the top of the metal shell, the receiving antenna passes through one side of the metal shell, and the modulation units are distributed in a matrix at the bottom of the metal shell. Such a design can facilitate the assembly of the system.

[0011] Preferably, the metal shell is provided with coaxial interfaces at positions corresponding to the transmitting antenna and the receiving antenna, respectively, to facilitate the installation of the transmitting antenna and the receiving antenna and ensure the sealing performance of the installation position.

[0012] Preferably, the circuit board is connected to a DC power supply to supply power to the circuit board.

[0013] The present invention also provides a monitoring method for the above-mentioned closed metal shell internal structure monitoring system, comprising the following steps:

[0014] S1: At the initial stage of assembling the internal structure of the metal shell, a network analyzer is used to measure the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna, and the measured data is stored in a computer to establish standard data;

[0015] S2: Regularly measure the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna;

[0016] S3: Compare the measurement results with standard data to determine whether the internal structure of the metal shell has changed.

[0017] Preferably, the step S1 also includes turning on or off the corresponding modulation unit according to a predetermined logic through the circuit board, so that the wavefront modulator has several working modes, and using a network analyzer to measure the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna in various working modes, and storing the measured data in the standard data. Step S2 includes measuring the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna in various working modes of the wavefront modulator. Beneficial Effects

[0018] The closed metal shell internal structure monitoring system provided by the present invention can determine the changes in different parts of the closed metal shell internal structure through the changes in the electromagnetic wave transmission amplitude between the transmitting antenna and the receiving antenna, thereby realizing real-time monitoring of the closed metal shell internal structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of a structure according to an embodiment of the present invention;

[0020] Figure 2 for Figure 1 Schematic diagram of the structure of the medium wavefront modulator;

[0021] Figure 3 for Figure 2 A schematic diagram of the structure of the front side of the middle modulation unit;

[0022] Figure 4 for Figure 2 A schematic diagram of the structure on the back of the middle modulation unit;

[0023] Figures 5 to 12 It is a simulation diagram of the electromagnetic wave beam modulated by the wavefront modulator in different modes;

[0024] Figures 13 to 16 The following are the transmission amplitude comparison diagrams of the wavefront modulator in different modes, when the internal components of the metal shell do not move, move 1mm, and move 10mm. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with embodiments and drawings.

[0026] like Figure 1 The closed metal shell internal structure monitoring system shown includes a transmitting antenna 2, a wavefront modulator 3, a receiving antenna 6 and a network analyzer 7, wherein the transmitting antenna 2 extends into the metal shell 1 to transmit electromagnetic waves to the metal shell 1.

[0027] The wavefront modulator 3 is used to modulate the wavefront of the electromagnetic wave in the metal shell 1. The wavefront modulator 3 is connected to a circuit board 4 and a computer 5. The computer 5 and the circuit board 4 can control the operation of the wavefront modulator 3 to modulate the direction and intensity of the electromagnetic wave beam reflected inside the metal shell 1. To facilitate power supply, the circuit board 4 is also connected to a DC power supply 41.

[0028] The receiving antenna 6 is used to receive electromagnetic waves in the metal shell 1. The network analyzer 7 is electrically connected to the transmitting antenna 2 and the receiving antenna 6 respectively, and is used to measure the transmission amplitude between the two antennas. By changing the transmission amplitude, it can be determined whether the internal structure of the metal shell 1 has changed.

[0029] For the convenience of description, this embodiment takes a conical metal shell 1 as an example, and a cylinder 10 installed in its internal space simulates the internal structure of the metal shell 1. The transmitting antenna 2 extends from the top of the metal shell 1, and the receiving antenna 6 is arranged on a side wall of the metal shell 1. Coaxial interfaces 9 are provided at the positions corresponding to the transmitting antenna 2 and the receiving antenna 6, and are respectively connected to the two port positions of the network analyzer 7 through coaxial cables 71.

[0030] The wavefront modulator 3 is arranged at the bottom of the metal shell 1. Figure 2 It can be seen that the wavefront modulator 3 is composed of a plurality of modulation units 31 distributed in a matrix.

[0031] Figure 3 and Figure 4 The specific structure of the modulation unit 31 is shown. The modulation unit 31 is made of microstrip material and includes a dielectric substrate 310. Microstrip metal sheets 311 are laid on the front and back surfaces of the dielectric substrate 310, and two or more modulation circuits 312 are formed on the front surface of the dielectric substrate 310. Two adjacent modulation circuits 312 are connected through a diode 313. The dielectric substrate 310 is provided with two metal through holes 314 at positions corresponding to each diode 313. The two poles of the diode 313 are connected to the interface of the cable 8 connected to the circuit board 4 through a wire 315.

[0032] The computer 5 and the circuit board 4 can control each diode 313 to be turned on or off. When the diode 313 is turned on, the corresponding modulation unit 31 reflects the electromagnetic wave. When the diode 313 is turned off, the corresponding modulation unit 31 absorbs the electromagnetic wave. Specifically, when the diode 313 is turned on, the modulation circuit 312 increases, otherwise it becomes shorter. The two states can reflect or absorb electromagnetic waves within a certain frequency band, and finally achieve the effect of modulating the direction and amplitude of the electromagnetic wave beam.

[0033] Figures 5 to 8 To adopt Figure 2 When the modulation unit 31 of the 3×3 array is shown, the electromagnetic wave beam simulation diagram modulated by the wavefront modulator 3 is shown in the different modulation units 31 open states, where: Figure 5 is the beam pattern in the fully open state, Figure 6 The beam pattern when modulation units 31 of No. 4, 5, and 6 are turned on and the rest are turned off. Figure 7 The beam pattern when modulation units 31 of No. 2, 4, 5, 6, and 8 are turned on and the rest are turned off. Figure 8 This is the beam pattern when modulation units 31 No. 1, 2, 3, 7, 8, and 9 are turned on and the rest are turned off.

[0034] The distribution form of the modulation unit 31 can be adjusted according to the shape of the metal shell 1 and its internal structure layout. Figures 9 to 12When a 9×9 array of modulation units 31 is used, the electromagnetic wave beam simulation diagram modulated by the wavefront modulator 3 is shown in the different modulation unit 31 opening states, where: Fig. 9 is the beam pattern when the modulation unit 31 is fully turned on, Fig.10 The beam pattern is when the modulation units 31 in the third and sixth columns of the array are turned on and the rest are turned off. Fig.11 The beam pattern when the second and seventh columns of modulation units 31 in the array are turned on and the rest are turned off, Fig.12 is the beam pattern in another state.

[0035] It can be seen from the above beam simulation diagram that by controlling the corresponding modulation unit 31 in the wavefront modulator 3 to be turned on or off by the circuit board 4, electromagnetic wave beams of different forms can be obtained. By selecting appropriate control logic according to the shape and internal structure of the metal shell 1, different parts inside the metal shell 1 can be scanned.

[0036] The monitoring method of the above-mentioned closed metal shell internal structure monitoring system is as follows:

[0037] First, after the equipment is assembled, that is, the internal structure of the metal shell 1 is assembled, and the system modules such as the transmitting antenna 2, the wavefront modulator 3, the receiving antenna 6, and the network analyzer 7 are assembled, the transmission amplitude between the transmitting antenna 2 and the receiving antenna 6 in the initial state is measured using the network analyzer 7, and the measured data is stored in the computer 5 to establish standard data.

[0038] Afterwards, the transmission amplitude between the transmitting antenna 2 and the receiving antenna 6 is measured regularly using the network analyzer 7, and the result is compared with the standard data. If there is a change, it can be determined that the internal structure of the metal shell 1 has changed.

[0039] By controlling the wavefront modulator 3 through the circuit board 4 to modulate electromagnetic wave beams of different directions and amplitudes, multiple sets of data can be obtained. Based on the comparison results, the position and amplitude of the changes in the internal structure of the metal shell 1 can be inferred, providing reference data for equipment inspection and maintenance.

[0040] Fig.13 It shows a comparison of the transmission amplitudes between the transmitting antenna 2 and the receiving antenna 6 when the wavefront modulator 3 adopts a 3×3 array and all modulation units 31 are turned on, in which the cylinder 10 inside the metal shell 1 remains stationary, moves 1 mm, and moves 10 mm.

[0041] Fig.14 3 is a comparison diagram of the transmission amplitude between the transmitting antenna 2 and the receiving antenna 6 in different working modes of the 3×3 array wavefront modulator 3 when the cylinder 10 does not move.

[0042] Fig.15 and Fig.16 The figures are respectively a comparison of the transmission amplitude between the transmitting antenna 2 and the receiving antenna 6 in different working modes of the wavefront modulator 3 after the cylinder 10 moves 1 mm and 10 mm.

[0043] Finally, it should be noted that the above description is only a preferred embodiment of the present invention. Under the guidance of the present invention, ordinary technicians in this field can make various similar expressions without violating the purpose and claims of the present invention, and such changes all fall within the scope of protection of the present invention.

Claims

1. A closed metal shell internal structure monitoring system, characterized in that: include: A transmitting antenna (2), which extends into the metal shell (1) and is used to transmit electromagnetic waves into the metal shell (1); A wavefront modulator (3) is installed inside the metal housing (1) and is connected to a circuit board (4) and a computer (5), and is used to modulate electromagnetic waves inside the metal housing (1). The wavefront modulator (3) includes a plurality of modulation units (31), and each modulation unit (31) can be controlled to be turned on or off by means of the computer (5) and the circuit board (4); A receiving antenna (6) for receiving electromagnetic waves in the metal housing (1); as well as A network analyzer (7), which is electrically connected to the transmitting antenna (2) and the receiving antenna (6), respectively; The modulation unit (31) comprises a dielectric substrate (310), the front and back surfaces of the dielectric substrate (310) are both provided with microstrip metal sheets (311), and at least two modulation circuits (312) are formed on the front surface, adjacent modulation circuits (312) are connected via diodes (313), and each diode (313) can be controlled to be turned on or off via a computer (5) and a circuit board (4); The transmitting antenna (2) extends into the metal shell (1) from the top, the receiving antenna (6) extends out from one side of the metal shell (1), and the modulation units (31) are distributed in a matrix at the bottom of the metal shell (1).

2. The closed metal shell internal structure monitoring system according to claim 1, characterized in that: The wavefront modulator (3) is connected to the circuit board (4) via a cable (8); two metal through holes (314) are provided on the dielectric substrate (310) of each modulation unit (31) at positions corresponding to the diodes (313), and are connected to the interface of the cable (8) via a wire (315).

3. The closed metal shell internal structure monitoring system according to claim 1 or 2, characterized in that: The metal shell (1) is provided with coaxial interfaces (9) at positions corresponding to the transmitting antenna (2) and the receiving antenna (6).

4. The closed metal shell internal structure monitoring system according to claim 1 or 2, characterized in that: The circuit board (4) is connected to a direct current power source (41).

5. The monitoring method of the internal structure monitoring system of a closed metal shell according to claim 1, characterized in that: The following steps are involved: S1: In the early stage of assembling the internal structure of the metal shell (1), the electromagnetic wave transmission amplitude between the transmitting antenna (2) and the receiving antenna (6) is measured using a network analyzer (7), and the measured data is stored in a computer (5) to establish standard data; S2: regularly measuring the amplitude of electromagnetic wave transmission between the transmitting antenna (2) and the receiving antenna (6); S3: Compare the measurement result with the standard data to determine whether the internal structure of the metal shell (1) has changed.

6. The monitoring method according to claim 5, characterized in that: The step S1 also includes turning on or off the corresponding modulation unit (31) according to a predetermined logic through the circuit board (4), so that the wavefront modulator (3) has a plurality of working modes, using a network analyzer (7) to measure the electromagnetic wave transmission amplitude between the transmitting antenna (2) and the receiving antenna (6) in various working modes, and storing the measured data in the standard data, and the step S2 includes measuring the electromagnetic wave transmission amplitude between the transmitting antenna (2) and the receiving antenna (6) in various working modes of the wavefront modulator (3).

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