Antenna device

Abstract

The present invention relates to the field of antenna manufacturing technology, and more specifically, to an antenna device which is small in size, compact in structure, and has antenna characteristics that do not change dramatically with changes in ambient temperature. The antenna device includes a first dielectric substrate, an antenna part is provided on the first dielectric substrate, and a second dielectric substrate is provided parallel to the first dielectric substrate. The invention is characterized in that a heating part is provided on the surface of the second dielectric substrate facing the back of the first dielectric substrate, an air insulation layer is formed between the first dielectric substrate and the second dielectric substrate, and an insulation wall is provided between the first dielectric substrate and the second dielectric substrate to surround the air insulation layer. The antenna device proposed by the present invention has the effect of reducing the change of component constants accompanying the environmental change of the antenna part because the insulation wall covering the space between the first dielectric substrate carrying the antenna and the second dielectric substrate oppositely provided is provided, and the heating part for adjusting the temperature in the space is provided.

Description

Technical field:

[0001] The present invention relates to the technical field of antenna manufacturing, in particular to an antenna device which forms an antenna loop on a plane substrate and has a small size, a compact structure, and antenna characteristics that do not change dramatically with ambient temperature changes. Background technology:

[0002] Small antenna devices for receiving milliwave or microwave bands need to ensure that the antenna's directivity, gain, and bandwidth meet the specified values ​​when the ambient temperature changes significantly. The antenna device uses a waveguide type, a multi-layer or single-layer strip antenna as the insulating layer, etc. Among them, since the single-layer strip antenna can be formed on the substrate plane using printed wiring technology, the yield is high.

[0003] It is known that in a strip antenna, the thicker the insulating layer, the higher the antenna gain, and it is a known technology to set a reflector to increase the gain. Regarding the gain (G), bandwidth (BW), and volume (V) of the antenna, there is a relationship: G×BW∝V. Therefore, G and BW are inversely proportional.

[0004] In the special opening 2019-47238 Figure 1 (Reference 1) discloses an antenna device in which a plurality of array antennas 100 are provided on one surface and a strip line as a ground plane (ground conductor) is formed on the other surface.

[0005] In WO2015 / 129089 Figure 2 (Reference 2) discloses an antenna device having a stacked array of a first dielectric 1, a second dielectric 3, and a third dielectric 4. Figure 6 (b) (reference 3) discloses an antenna device which accommodates a multi-layer substrate 30 inside a housing 11, and provides a cover 21 covering an opening of the housing 11. Even if a temperature difference occurs between the inside and the outside of the cover 21, the distance between the wiring antenna 61 and the non-powered element 71 is kept constant by the protrusion 25 of the cover 21.

[0006] However, neither Patent Document 1 nor Patent Document 2 describes changes in substrate characteristics and antenna characteristics caused by wide changes in the thermal expansion coefficient. In other words, when the substrate warps due to temperature changes, antenna characteristics such as antenna directivity, performance index Q, and frequency band will change. There is also no description of relevant technical means for overcoming the impact of temperature changes on antenna characteristics.

[0007] The content recorded in Patent Document 3 focuses on the pressure changes caused by the temperature difference between the inside and the outside. Although the gap between the patch antenna 61 and the passive device 71 in the protrusion 25 of the cover 21 becomes constant, the gain characteristics and frequency band characteristics are improved, but only the relationship with the passive device 71 is explained. Summary of the invention:

[0008] In view of the shortcomings and deficiencies of the prior art, an object of the present invention is to solve the above problems and provide an antenna device that maintains antenna characteristics without significant changes in ambient temperature.

[0009] The present invention is achieved by the following measures:

[0010] An antenna device comprises a first dielectric substrate, on which an antenna portion is arranged, and a second dielectric substrate arranged parallel to the first dielectric substrate, wherein a heating portion is arranged on the surface of the second dielectric substrate facing the back side of the first dielectric substrate, an air insulation layer is formed between the first dielectric substrate and the second dielectric substrate, and an insulation wall arranged around the air insulation layer is arranged between the first dielectric substrate and the second dielectric substrate.

[0011] The heating part on the second dielectric substrate of the present invention is realized by heating resistors distributed in a spiral, serpentine or bow shape.

[0012] The antenna unit of the present invention includes an antenna arranged on the upper surface of a first dielectric substrate for receiving a high-frequency signal transmitted to the surface of the first dielectric substrate, and a strip line located on the back of the first dielectric substrate for transmitting the high-frequency signal; further, the antenna unit includes an antenna for receiving a high-frequency signal transmitted to the surface of the first dielectric substrate, a strip line arranged on the back of the first dielectric substrate including the antenna for transmitting the high-frequency signal, and a coaxial line penetrating the central portion of the first dielectric substrate for transmitting the high-frequency signal from the strip line.

[0013] The second dielectric substrate of the present invention is also provided with a grounding side connected to the aforementioned coaxial line and a negative terminal connected to the heating part, and the positive terminal of the heating part is connected to the power circuit located on the back of the second dielectric substrate through the side surface of the second dielectric substrate.

[0014] The second dielectric substrate of the present invention is provided with a large hole portion 7a in the central portion, and an insulating layer 7b is provided on the back of the second dielectric substrate. The insulating layer 7b is a ceramic material coated with a glass film layer on the surface. The second dielectric substrate is relatively separated from the back of the first dielectric substrate, and a heating portion with a resistance value of 0.05 to 0.2Ω is formed on the entire surface.

[0015] The adjacent gap (L) between the vortex (radial) or serpentine or arcuate (Mianda) heating parts of the present invention is less than 20 μm, so that the relationship of wavelength (λ)>>L is used to maintain the function of the second dielectric substrate as a reflector.

[0016] The surface of the first dielectric substrate of the present invention is provided with a conductive cover plate, and the surfaces of the antenna part, the transmission line and the power supply part on the first dielectric substrate are covered by the conductive cover plate through which high-frequency signals can pass, and the signal information output from the transmission line is coaxially converted at the power supply unit; the front end of the conductive cover plate has a protrusion, which is fixed through a small hole set on the surface of the first dielectric substrate.

[0017] The interior of the heat-insulating wall of the present invention is hollow, and is used to form an air heat-insulating layer, thereby further improving the heat-insulating effect; further, the interior of the heat-insulating wall is filled with a resin that is permeable to high-frequency signals.

[0018] The antenna device proposed in the present invention has an insulating wall covering the space between the first dielectric substrate on which the antenna is mounted and the second dielectric substrate arranged opposite thereto, and a heating portion for adjusting the temperature in the space, thereby having the effect of reducing the change in component constants accompanying the environmental change of the antenna part. Description of the drawings:

[0019] Attached Figure 1 A plan view of an antenna device according to Embodiment 1 of the present invention Figure 1 (a) and cross-section Figure 1 (b).

[0020] Attached Figure 2 This is a plan view showing the configuration of a reflector of the antenna device according to the first embodiment of the present invention.

[0021] Attached Figure 3 It is a schematic diagram of a coaxial conversion portion of the antenna device according to Embodiment 1 of the present invention.

[0022] Attached Figure 4 It is a diagram for explaining the structure of a signal processing circuit of the antenna device according to the first embodiment of the present invention.

[0023] Attached Figure 5 It is a schematic diagram showing the structure of a reflector of an antenna device according to Embodiment 2 of the present invention.

[0024] Attached Figure 6 A plan view of an antenna device according to Embodiment 3 of the present invention Figure 6 (a) and cross-section Figure 6 (b).

[0025] Figure numerals: 1: first dielectric substrate; 1a: large hole, 1b: small hole, 1c: insulating layer, 1d: copper foil pattern, 1e: ground pattern (GND); 2: antenna part, 2a: wide pattern, 2b: slender pattern; 3: transmission line (microstrip line); 4: spare terminal; 5: power supply part, 5a: solder or conductive resin, 5b: solder or conductive resin, 5c: dielectric layer, 5d: ground part; 6: cover plate; 7: second dielectric substrate, 7a: large hole part; 8: heating part; 9: signal processing part; 10: coaxial conversion part; 11: internal space, 11a: insulation wall; 12: short-circuit plate; 13: band pass filter (BPF); 14: low noise amplifier (Low noise AMP); 15: mixer (Mixer); 16: local oscillator; 17: intermediate frequency amplifier (IF AMP); 18: signal processing IC; 19: temperature control circuit (TM); 20: external terminal; 21: external system, 21a: equipment power supply, 21b: heating part driving power supply; 22: temperature display; 110: sealing part; 120: short-circuit board. Specific implementation method:

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] Figure 1 It is a top view and a cross-sectional view of an antenna device composed of a parallel-powered array according to the first embodiment of the present invention. Figure 1 The first dielectric substrate 1 is provided with a large hole (1a) in the central part and a small hole (1b) in the peripheral part, and the insulating layer 1c is a liquid crystal polymer (FCP) material; a copper foil pattern 1d is formed on one surface, and the other surface (back side) is used as a grounding pattern (ground conductor part) 1e; the antenna part 2 is composed of a conical antenna pattern 2a extending toward the front end of the pattern and a rectangular elongated antenna pattern 2b, and the center of the elongated antenna pattern 2b is connected to the transmission line 3, and S represents a branch located at the central position of the antenna pattern 2b.

[0029] If the center position of the first dielectric substrate 1 is set as the power supply unit 5, the length of each transmission line to each antenna unit 2 is set to the interval distance A, and the interval distance B using the high-frequency signal is shortened by an integral multiple of one wavelength (λg), then the distance from the branching portion S to the center of the first dielectric substrate 1 of the transmission line 3 is the line length of A+B or 2A+B. This is to maintain the state of the received high-frequency signal in phase from the power supply unit 5. In addition, a spare terminal 4 for fine-tuning the performance (Q) and line impedance (Z0) is provided in the interval distance A, and if necessary, the spare terminal 4 and the transmission line 3 are heat-pressed by wire bonding or metal tape.

[0030] The signal information output from the transmission line 3 is coaxially converted at the power supply unit 5. The surfaces of the antenna unit 2, the transmission line 3, and the power supply unit 5 are covered by a conductive cover plate 6 that can pass high-frequency signals. The conductive cover plate 6 has a protrusion 6a at the front end and is fixed by a small hole 1b set on the surface of the first dielectric substrate 1.

[0031] The second dielectric substrate 7 has a large hole 7a in the center, and the insulating layer 7b is a ceramic material coated with a glass film layer on the surface, which is opposite to the back surface of the first dielectric 1 and forms a heat generating portion 8 with a resistance value of 0.05 to 0.2Ω on the entire surface.

[0032] In addition, because the adjacent gaps (L) between the vortex (radial) or serpentine or bow-shaped (Mianda) heating parts 8 are less than 20 μm, the relationship of wavelength (λ) >> L is used to maintain the function of the reflector; a signal processing part 9 is provided on the back side of the second dielectric substrate 7, and the signal processing part 9 includes a wiring pattern formed by a device (component) or a conductive material such as gold.

[0033] The coaxial conversion part 10 electrically connects the signal information from the transmission line 3 to the prescribed pattern of the signal processing part 9 of the second dielectric substrate 7. The ground terminal (GND) of the coaxial conversion part 10 is used as a ground line for high-frequency signals. The internal space 11 of the first dielectric substrate 1 and the second dielectric substrate 7 is covered by four partition walls 11a, and is a closed space for maintaining (insulating) the Joule heat generated by the heat generating part 8. A part of the pattern connection on the back side of the second dielectric substrate 7 is connected at the same potential using a short-circuit plate or a metal sheet (metal strip) 12 on the side.

[0034] Figure 2 FIG. 1 is a plan view showing the structure of a reflector of an antenna device according to Embodiment 1 of the present invention. Figure 2In the figure, one end arranged near the center of the surface of the second dielectric substrate 7 is set as a negative electrode (-), the other end arranged at the edge is set as a positive electrode (+), and the middle is used as a heating portion pattern 8 whose entire surface is made of ruthenium oxide material in a vortex or Mianda (snake) shape. In addition, since the positive electrode is connected to the signal processing part on the back, it is connected to a short-circuit plate 12 such as an elastic paper clip.

[0035] Figure 3 1 is a schematic diagram of a coaxial conversion unit of an antenna device according to Embodiment 1 of the present invention. Figure 3 In the embodiment, the front end of one core wire portion 5a of the high frequency signal passing through the center of the coaxial conversion portion 10 is used as the power supply portion 5, and is connected to the pattern of the transmission line 3 using solder or conductive resin 5b, and the ground conductor portion 5d located outside the dielectric layer 5c around the core wire portion 5a of the coaxial conversion portion 10 is connected to the ground conductor 1e on the back surface of the first dielectric substrate 1 by a wire, and is connected to the heating portion 8 on the surface of the second dielectric substrate 7, thereby, the ground conductor 1d of the high frequency circuit and the negative electrode of the heating portion 8 become the same potential on the surface of the second dielectric substrate 7. The high frequency signal passes through the large hole 7a of the second dielectric substrate 7, but the ground side of the coaxial conversion portion 10 is a mesh twisted pair, so that the inappropriate situation such as the GND potential rise caused by the feedback current of the heating portion 8 does not occur.

[0036] The first dielectric substrate 1 and the second dielectric substrate 7 are spaced apart at about 1 / 4 wavelength of the frequency (λ) used, and are fixed by fine adjustment using an insulating coaxial cover 10a;

[0037] Figure 4 Schematic diagram of signal processing of the antenna device according to Embodiment 1 of the present invention. Figure 4 In the embodiment, a high-frequency signal appearing on a coaxial conversion portion 10 located in the center of a second dielectric substrate 7 is amplified by a low-noise amplifier 14 via a band-pass filter (BPF) 13 for removing environmental noise, and then frequency mixing is started by a mixer (Mixer) 15 and a local oscillator (Local Osc.) 16, and is converted into an intermediate frequency signal under the action of an intermediate frequency amplifier 17; a temperature control circuit (19) includes a temperature detector having a positive or negative temperature coefficient, and sends environmental temperature information to a signal processing IC 18.

[0038] Next, the operation and related effects of the heating unit 8 are described: in the case of a high-frequency circuit, due to the intervention of a dielectric, a characteristic curve of the physical constant attenuating with temperature is obtained with the physical constant (dielectric constant) as the horizontal axis.

[0039] The heating unit 8 is set to start / stop based on the ambient temperature information, and the starting temperature is preferably set to be less than 5°C. Therefore, the heating unit 8 gradually increases the output toward the low temperature side from ON based on the signal of the signal processing IC 18, controls the temperature at around 5°C, and then gradually reduces the output.

[0040] The heat generating unit 8 is not a common power source but an independent power source having a maximum power capacity of about 20 W, and performs variable voltage or pulse control on the external system 21 .

[0041] In the signal processing IC 18, the signal information and temperature information from the intermediate frequency are digitized and sent from the external terminal (SIN) (TMCONT) 20 to the external system 21. The external system 21 sends a synchronization signal to the external terminal 20 (SYSC) for controlling the system signal of the antenna device, and has a power supply for the driving device and a power supply for the heating part 8; input and output are to the external terminal 20 (VDD, AGND). In addition, the power supply for the heating part 8 is returned from the external terminal 20 (TMV) via the short-circuit plate 12 and a part of the ground conductor 5d on the coaxial converter 10 side from the external terminal 20 (TMGND). The external system 21 is installed with a power supply 21a for driving each device and a power supply 21b for driving the heating part 8. A signal is sent from the external system 21 to the display 22 that displays the ambient temperature.

[0042] According to an antenna device of embodiment 1, since a heat-insulating wall is provided to cover the space between a first dielectric substrate on which an antenna is mounted and a second dielectric substrate arranged opposite thereto, and a heating portion is provided on the side of the second dielectric 7 for adjusting the temperature in the space, it has the effect of reducing the change in the component constant of the antenna part accompanying the change in the environment.

[0043] Embodiment 2:

[0044] Figure 5 FIG. 1 is a schematic diagram of the structure of the reflector of the antenna device according to the second embodiment of the present invention. Figure 2 In the figure, a spiral heating portion 8 is provided. When the sheet resistance value of the heating portion is low, the desired resistance value can be obtained by bending the pattern multiple times in a Mianda shape. It is not necessary to set the bending gap portion to adopt a floating island pattern, thereby maintaining the function of the high-frequency reflector.

[0045] As described above, according to the antenna device of embodiment 2, a heat-insulating wall is provided in the space between the first dielectric on which the antenna is mounted and the second dielectric substrate arranged opposite thereto, and a heating portion for adjusting the temperature in the space is provided on the reflector of the second dielectric substrate. Since the pattern covers the entire surface of the reflector, the function of the reflector is maintained.

[0046] Embodiment 3:

[0047] Figure 6FIG. 1 is a schematic plan view showing the structure of a reflector of an antenna device according to Embodiment 3 of the present invention. Figure 1 In the embodiment, the heat generated by the space portion 11 is radiant heating. Figure 6 In the embodiment, the filling resin that can transmit the high-frequency signal through the space part 11 serves as the sealing part 110 for conductive heating; as described above, according to the antenna device of implementation state 3 of the present invention, the resin that can transmit the high-frequency signal is filled in the insulation wall 11a, so the insulation time is prolonged, and by contacting with the heat generating part 8, the effect of protecting the surface of the heat generating part 8 can be achieved at the same time.

[0048] The antenna device proposed in the present invention has an insulating wall covering the space between the first dielectric substrate on which the antenna is mounted and the second dielectric substrate arranged opposite thereto, and a heating portion for adjusting the temperature in the space, thereby having the effect of reducing the change in component constants accompanying the environmental change of the antenna part.

Claims

1. An antenna device, comprising a first dielectric substrate, an antenna portion being arranged on the first dielectric substrate, a second dielectric substrate being arranged parallel to the first dielectric substrate, a heating portion being arranged on the surface of the second dielectric substrate facing the back of the first dielectric substrate, an air insulation layer being formed between the first dielectric substrate and the second dielectric substrate, and an insulation wall being arranged around the air insulation layer between the first dielectric substrate and the second dielectric substrate; characterized in that: The antenna part includes an antenna arranged on the upper surface of the first dielectric substrate for receiving a high-frequency signal transmitted to the surface of the first dielectric substrate and a strip line located on the back of the first dielectric substrate for transmitting the high-frequency signal; the antenna part includes an antenna for receiving a high-frequency signal transmitted to the surface of the first dielectric substrate, a strip line arranged on the back of the first dielectric substrate including the antenna for transmitting the high-frequency signal, and a coaxial line passing through the central part of the first dielectric substrate for transmitting the high-frequency signal from the strip line; the second dielectric substrate is also provided with a grounding side connected to the coaxial line and a negative electrode terminal connected to the heating part, and the positive electrode of the heating part is connected to the power circuit located on the back of the second dielectric substrate through the side of the second dielectric substrate.

2. The antenna device according to claim 1, characterized in that: The heating part on the second dielectric substrate is realized by heating resistors distributed in a spiral or serpentine shape.

3. The antenna device according to claim 1, characterized in that: The interior of the heat-insulating wall is hollow.

4. The antenna device according to claim 1, characterized in that: The interior of the insulation wall is filled with a resin that is transparent to high-frequency signals.

5. The antenna device according to claim 2, characterized in that: The back of the second dielectric substrate is provided with an insulating layer, which is a ceramic material coated with a glass film layer. The second dielectric substrate is relatively separated from the back of the first dielectric substrate, and a heating portion with a resistance value of 0.05-0.2Ω is formed on the entire surface.

6. The antenna device according to claim 2, characterized in that: The adjacent gap L between the spiral or serpentine heat generating parts is less than 20 μm, so that the relationship of wavelength λ>>L is used to maintain the function of the second dielectric substrate as a reflector.

7. The antenna device according to claim 1, characterized in that: A conductive cover is provided on the surface of the first dielectric substrate. The surfaces of the antenna part, the transmission line and the power supply part on the first dielectric substrate are covered by the conductive cover through which high-frequency signals can pass. The signal information output from the transmission line is coaxially converted at the power supply part. A protrusion is provided at the front end of the conductive cover and is fixed through a small hole provided on the surface of the first dielectric substrate.

8. The antenna device according to claim 1, characterized in that: The heating unit is not a common power source, but an independent power source with a power capacity not exceeding 20W, and has a variable voltage or pulse control function.

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