Antenna device and protection device for electronic circuits

Abstract

In an antenna device, it is configured to protect the built-in electronic circuit from the effect of electric stress and to mitigate the effect on signal transmission. It is provided with an antenna part (11), a substrate (12) for connecting the antenna part (11), an electronic circuit (14) provided on the substrate (12), and a reactance adjusting device (16) for canceling the electric reactance of the electric stress applied to the constituent part of the electronic circuit (14). The substrate (12) includes a substrate input part (A) and a circuit input part (B). The reactance adjusting device (16) is provided between the substrate input part (A) and the circuit input part (B) and is connected with a ground part.

Description

Technical Field

[0001] This invention relates to antenna devices that can be mounted on mobile bodies and the like, as well as protection devices for electronic circuits. Background Technology

[0002] For example, in vehicle-mounted antenna devices, when electronic components for multiple frequency bands are arranged close together in a single housing, interference may occur between the electronic components, or external noise may be introduced, preventing the antenna from achieving the designed performance. With this in mind, Patent Document 1 discloses a vehicle-mounted antenna device in which one of the two antenna elements corresponding to two frequency bands is connected to an attenuation circuit that attenuates the signal of the other frequency band.

[0003] Furthermore, Patent Document 2 discloses an antenna device with a protection circuit between the antenna section and the electronic circuit (external connection terminal), one end of which is grounded and the other end is connected to the line connecting the antenna section and the electronic circuit. This protection circuit directs surge current caused by surge voltage that momentarily exceeds the steady state to the ground side.

[0004] Such attenuation circuits or protection circuits typically function as protective devices to eliminate electrical stress in electronic circuits used in environments where they may be subjected to electrical stress caused by unintentionally generated electromagnetic fields, voltages, or currents.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: JP 2020-136880

[0008] Patent Document 2: JP 2019-125861 Summary of the Invention

[0009] The protective devices described in Patent Documents 1 and 2 are extremely useful for electronic circuits that must be used in environments where they may be subjected to electrical stress.

[0010] However, such devices are not used to directly transmit signals from the input side to the output side of electronic circuits. Therefore, from a signal transmission point of view, this becomes an additional unnecessary load, and sometimes, depending on the operating frequency band of the electronic circuit, the reactance of the protection device can become so large as to be non-negligible. Especially when a protection device is added between the antenna section and the electronic circuit, impedance mismatch or increased power insertion loss can sometimes lead to a decrease in the gain characteristics or VSWR characteristics of the antenna section observed from the electronic circuit side.

[0011] One example of the object of the present invention is that, in an antenna device, components of electronic circuits used in environments where they may be subjected to electrical stress are protected from such stress, and the impact on signal transmission is mitigated. Another object of the present invention will become clear from the description herein.

[0012] One aspect of the present invention comprises: an antenna section; a substrate to which the antenna section is connected; an electronic circuit provided on the substrate; and a reactance adjustment device that cancels out the reactance of electrical stress applied to components of the electronic circuit in the operating frequency band, the substrate having a substrate input section that serves as an input interface between the antenna section and the antenna section, the reactance adjustment device being provided between the substrate input section and the electronic circuit and connected to a ground section for the antenna device.

[0013] Another aspect of the present invention provides an antenna device comprising: an antenna section; a substrate to which the antenna section is connected; an electronic circuit disposed on the substrate; and a reactance adjustment device for reactance cancellation of electrical stress applied to components of the electronic circuit in the operating frequency band, the substrate having an external connection portion for connection to an external electronic device, the reactance adjustment device being disposed between the electronic circuit and the external connection portion and connected to a ground portion.

[0014] Another aspect of the present invention provides a protection device for an electronic circuit, comprising: an electronic circuit; an additional device attached to protect the constituent components of the electronic circuit from electrical stress, which is connected between the input side or output side of the electronic circuit and a ground portion; and a reactance adjustment device for canceling the reactance of the additional device in the operating frequency band.

[0015] Invention Effects

[0016] Based on the above aspects, it is possible to protect the components of electronic circuits from electrical stress and to mitigate the impact on signal transmission. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating a basic configuration example of an antenna device to which the present invention can be applied.

[0018] Figure 2 This is a schematic diagram illustrating an example of the configuration of an antenna device with only additional components.

[0019] Figure 3 This is a schematic diagram showing an example of the configuration of an antenna device according to the first embodiment of which is equipped with a reactance adjustment device.

[0020] Figure 4A This refers to the reactance regulating device itself, and Figure 2 as well as Figure 3Smith chart of the impedance trace in the antenna device.

[0021] Figure 4B It is the reactance regulation device itself, and Figure 2 as well as Figure 3 VSWR characteristic diagram of the antenna device.

[0022] Figure 5 It means Figure 2 as well as Figure 3 A graph showing the insertion loss characteristics of an antenna device.

[0023] Figure 6A This is a diagram showing a specific example of a reactance regulating device.

[0024] Figure 6B This is a diagram showing a specific example of a reactance regulating device.

[0025] Figure 6C This is a diagram showing a specific example of a reactance regulating device.

[0026] Figure 6D This is a diagram showing a specific example of a reactance regulating device.

[0027] Figure 6E This is a diagram showing a specific example of a reactance regulating device.

[0028] Figure 6F This is a diagram showing a specific example of a reactance regulating device.

[0029] Figure 6G This is a diagram showing a specific example of a reactance regulating device.

[0030] Figure 7 This is a diagram illustrating an example of a reactance regulating device constructed using a conductor pattern.

[0031] Figure 8 This is a schematic diagram showing an example of the configuration of the components of the antenna device according to the first embodiment.

[0032] Figure 9 This is a schematic diagram showing an example of the configuration of the antenna device according to the second embodiment.

[0033] Figure 10A It is an expression Figure 2 as well as Figure 9 Smith chart of impedance traces in an antenna device

[0034] Figure 10B yes Figure 2 as well as Figure 9 VSWR characteristic diagram of the antenna device.

[0035] Figure 11 It is an expression Figure 2 as well as Figure 9 A graph showing the insertion loss characteristics of an antenna device.

[0036] Figure 12 This is a schematic diagram showing an example of the configuration of the antenna device according to the third embodiment.

[0037] Figure 13A It is an expression Figure 2 as well as Figure 12 Smith chart of the impedance trace in the antenna device.

[0038] Figure 13B yes Figure 2 as well as Figure 12 The antenna device VSWR characteristic diagram.

[0039] Figure 14 It is an expression Figure 2 as well as Figure 12 A graph showing the insertion loss characteristics of an antenna device.

[0040] Figure 15 This is a schematic diagram showing an example of the configuration of the antenna device according to the fourth embodiment.

[0041] Figure 16A yes Figure 2 as well as Figure 15 VSWR characteristic diagram of the antenna device.

[0042] Figure 16B yes Figure 2 as well as Figure 15 VSWR characteristic diagram of the antenna device.

[0043] Figure 17 This is a graph showing the insertion loss characteristics of the antenna device of the fourth embodiment, comparing the case with only a Zener diode with the case with both a Zener diode and a TVS diode.

[0044] Figure 18 This is a schematic diagram showing an example of the configuration of the antenna device according to the fifth embodiment.

[0045] Figure 19A This is an example diagram illustrating the alternative configuration of the reactance adjustment device.

[0046] Figure 19B This is an example diagram illustrating the alternative configuration of the reactance adjustment device.

[0047] Figure 19C This is an example diagram illustrating the alternative configuration of the reactance adjustment device.

[0048] Figure 19D This is an example diagram illustrating the alternative configuration of the reactance adjustment device.

[0049] Figure 20A This is an example diagram illustrating the connection of the reactance regulating device.

[0050] Figure 20B This is an example diagram illustrating the connection of the reactance regulating device.

[0051] Figure 21 This is a diagram illustrating another example of a reactance regulating device constructed using conductor patterns.

[0052] Figure 22 This is a schematic diagram showing an example of the configuration of the antenna device according to the sixth embodiment.

[0053] Figure 23 This is a schematic diagram showing a configuration example of an antenna device according to a modified example of the sixth embodiment.

[0054] Figure 24A This is an explanatory diagram showing specific examples of the additional devices and reactance adjustment devices of the sixth embodiment.

[0055] Figure 24B This is an explanatory diagram showing specific examples of the additional devices and reactance adjustment devices of the sixth embodiment.

[0056] Figure 24C This is an explanatory diagram showing specific examples of the additional devices and reactance adjustment devices of the sixth embodiment.

[0057] Figure 25 This is a graph showing the insertion loss in the antenna device of the sixth embodiment, comparing the case with only a Zener diode with the case with both a Zener diode and a TVS diode.

[0058] Figure 26 This is a schematic diagram showing an example of the configuration of the antenna device according to the seventh embodiment.

[0059] Figure 27 This is a schematic diagram showing an example of the configuration of the antenna device according to the eighth embodiment. Detailed Implementation

[0060] Hereinafter, an example of implementing the present invention as an antenna device mounted on a moving body such as a vehicle will be described. This antenna device receives signals in the 470MHz to 720MHz frequency band of the DTTB (Digital Television Terrestrial Broadcasting System).

[0061] [First Implementation]

[0062] first, Figure 1 A basic configuration example of an antenna device to which the present invention can be applied is shown. Figure 1 The antenna device 10 shown is configured such that an antenna section 11 and a circuit board 12 are housed in an antenna housing (described later) mounted on a vehicle roof or similar surface. The antenna section 11 is constructed using planar conductors or linear (including rod-shaped) conductors, or combinations thereof, that resonate in the DTTB frequency band. The circuit board 12 has a board input section A serving as an input interface to the antenna section 11, and a circuit input section B serving as an input interface to the electronic circuit 14. The electronic circuit 14 is equipped with electronic components including active elements such as transistors or diodes. The board input section A and the circuit input section B are electrically connected together using lines 13, such as conductor patterns.

[0063] Furthermore, the arrangement between the substrate input section A and the circuit input section B is not limited to a conductor pattern. One or more circuits may be arranged between the substrate input section A and the circuit input section B. For example, one or both of the additional device 15 described later or the reactance pattern 211 may be arranged.

[0064] In the DTTB band, the characteristic impedance when viewed from the substrate input section A towards the antenna section 11 is 50Ω in this example, and the impedance when viewed from the circuit input section B towards the electronic circuit 14 is also 50Ω in this example. In this case, if the impedance of the line 13 between the substrate input section A and the circuit input section B is also 50Ω, then the impedance matching of the system from the antenna section 11 to the electronic circuit 14 results in almost no insertion loss of electrical power (signal level) during signal transmission.

[0065] The electronic circuit 14 is constructed by including the aforementioned multiple electronic components, but many of these electronic components are not resistant to the aforementioned electrical stress. Therefore, if an antenna section for other frequency bands and electronic circuits are located near the antenna housing, or if a strong transmission wave is output from an antenna device mounted on another vehicle traveling nearby, or if a surge voltage that momentarily exceeds the steady state is generated, the electronic circuit 14 will be significantly affected even if it is an electromagnetic wave or voltage of a frequency different from the DTTB band. Therefore, in the first embodiment, as... Figure 2 As shown in the antenna device 20, an additional device 15 for eliminating electrical stress is provided at the front end of the electronic circuit 14.

[0066] In this example, the additional device 15 is a two-terminal semiconductor diode, one end of which is connected to line 13 and the other end is connected to ground.

[0067] The additional device 15 has a capacitance (capacitive reactance) as the inter-terminal capacitance. The inter-terminal capacitance varies from approximately 0.2pF to 30pF depending on the type of semiconductor diode, but in this example, it is 7pF in the DTTB band. If this additional device 15 is bypassed to line 13, although it eliminates the electrical stress on the components of the electronic circuit 14, it adds an unnecessary component for signal transmission. Therefore, impedance mismatch inevitably occurs between the antenna section 11 and the electronic circuit 14 in the DTTB band. That is, the impedance of the electronic circuit 14 viewed from the substrate input section A is capacitive in the DTTB band, and the insertion loss of power transferred from the substrate input section A to the circuit input section B increases. Therefore, the antenna gain decreases.

[0068] Therefore, in the first embodiment, like Figure 3 Similar to antenna device 30, the additional device 15 is used to eliminate electrical stress, and a reactance regulating device 16 is provided in parallel with the additional device 15 to offset the change in reactance caused by the presence of the additional device 15. In this example, the reactance regulating device 16 is an inductive reactance element with an inductance of 10.2nH in the DTTB band, one end of which is connected to line 13 and the other end is connected to ground. This reactance regulating device 16 is used to eliminate the change in impedance to capacitance when a semiconductor diode is used as the additional device 15.

[0069] The type and form of the inductive element can be arbitrary, but by using a surface mount inductor, there are the following advantages: it is smaller (thinner) than a coil, and the design dimensions of the circuit board 12 do not need to be changed even when it is mounted together with the additional device 15 on the circuit board 12.

[0070] In addition, it can also replace surface mount inductors and use a combination of multiple conductor patterns to form inductive reactance elements.

[0071] The inductance of the reactance regulating device 16 is preferably set in such a way that its reactance component is in a complex conjugate relationship with respect to the inter-terminal capacitance of the auxiliary device 15. “Complex conjugate” means that they are opposite in polarity and equal in magnitude.

[0072] In other words, the "complex conjugate relationship" means that when the reactance of the auxiliary device 15 is -jX, the reactance of the reactance adjustment device 16 becomes +jX. Therefore, in the DTTB band, the capacitive reactance of the auxiliary device 15 is canceled out by the inductive reactance of the reactance adjustment device 16, and the impedance between the substrate input section A and the circuit input section B becomes 50Ω. Specifically, in numerical terms, at a frequency of 595MHz, the capacitive reactance of the auxiliary device 15 is approximately -j24.1 (Ω), and in contrast, the inductive reactance of the reactance adjustment device 16 is +j24.1 (Ω), resulting in a complex conjugate impedance relationship.

[0073] The reactance regulating device 16 is positioned as close as possible to the location of the auxiliary device 15. This suppresses the inductance and capacitance of the line 13 from the auxiliary device 15 to the reactance regulating device 16. Preferably, the reactance regulating device 16 is positioned within 1 / 10 of the wavelength of the highest frequency in the DTTB band, starting from the location where the auxiliary device 15 is located. This further reduces the influence of the inductance and capacitance of the line 13.

[0074] Next, the antenna characteristics of the antenna device 30 of the first embodiment will be explained. Figure 4A This is a Smith chart showing the impedance traces of the individual reactance regulating device 16, antenna assembly 20, and antenna assembly 30. As is known, the upper half of the Smith chart represents inductive impedance, and the lower half represents capacitive impedance. In the figure, solid line 401 represents the impedance trace of antenna assembly 20, dashed line 402 represents the impedance trace of antenna assembly 30, and dashed line 403 represents the impedance trace of the individual reactance regulating device 16. At position 1.0 in the center of the Smith chart, the impedance matching between antenna section 11 and electronic component 14 is minimized, resulting in minimal insertion loss. Therefore, to minimize the insertion loss between antenna section 11 and electronic component 14 in the DTTB band, it is preferable that the impedance trace passes through position 1.0 in the center of the Smith chart. The above description is common to the Smith charts used in this specification.

[0075] like Figure 4A As shown, the impedance trace 403 in the reactance adjustment device 16 is inductive throughout the entire DTTB band. The impedance trace 401 in the antenna assembly 20 is capacitive throughout the entire DTTB band. Furthermore, the impedance trace 401 and the impedance trace 403 in the reactance adjustment device 16 are almost symmetrical about the horizontal axis and are located in the lower half of the Smith chart. On the other hand, the impedance trace 402 in the antenna assembly 30 passes through the horizontal axis near the center of the Smith chart at 1.0.

[0076] In this way, the antenna device 30, which has a reactance adjustment device 16 whose impedance has a complex conjugate relationship with the inter-terminal capacity of the additional device 15, reduces the insertion loss caused by the presence of the additional device 15.

[0077] Figure 4B This is a VSWR characteristic diagram for antenna devices 20 and 30. In the diagram, the vertical axis represents VSWR, and the horizontal axis represents frequency (MHz). The solid line 411 represents the VSWR characteristic of antenna device 20, and the dotted line 412 represents the VSWR characteristic of antenna device 30. Figure 4BAs shown by solid line 411, the VSWR in antenna device 20 increases almost linearly with increasing frequency, with a minimum value of 2.7 and a maximum value of 4.3. In contrast, as... Figure 4B As shown by the dotted line 412, the VSWR of the antenna device 30 has a minimum value of 1.0 and a maximum value of 1.9 near the frequency of 600MHz.

[0078] In this way, the antenna device 30, which has a reactance adjustment device 16 whose impedance is in a complex conjugate relationship with the inter-terminal capacitance of the additional device 15, has a VSWR of less than 2 at all frequencies in the DTTB band.

[0079] Figure 5 This is a graph representing the insertion loss characteristics of antenna devices 20 and 30. In this graph, [the graph will show...] Figure 1 The insertion loss in the antenna device 10 shown is set to 0 dB. In the figure, solid line 501 represents the insertion loss (dB) based on the configuration of antenna device 20. In the configuration of antenna device 20, the insertion loss is greater than -1 dB throughout the DTTB band. Furthermore, the insertion loss increases with increasing frequency, reaching -2.1 dB near 720 MHz, which is the upper limit frequency of the DTTB band. Dashed line 502 represents the insertion loss (dB) of antenna device 30. The insertion loss in antenna device 30 is almost 0 dB throughout almost the entire DTTB band, and the variation based on frequency is small, converging to a maximum of approximately -0.4 dB.

[0080] This is because in the antenna device 20 with only the additional device 15, the degree of impedance mismatch increases with the operating frequency. In contrast, in the antenna device 30 where the reactance adjustment device 16 is connected in parallel with the additional device 15, even if the reactance of the additional device 15 changes with the operating frequency, the reactance adjustment device 16 cancels out the changed reactance, thus offsetting the impedance variation caused by the additional device 15. Therefore, in the antenna device 30, the stress relief effect of the additional device 15 can be maintained, and the increase in impedance mismatch or power insertion loss can be effectively suppressed.

[0081] <Modifications of the First Embodiment>

[0082] In the first embodiment, the description assumes that the additional device 15 is a semiconductor diode, i.e., a capacitive reactance that generates capacitance in the DTTB band. However, the additional device 15 may sometimes be a device that changes the impedance from the substrate input section A to the circuit input section B to inductive form, such as an inductor. In this case, the reactance adjustment device 16 can be used. Figure 6AThe capacitive reactance element 61 is shown. This capacitive reactance element 61 can be, for example, a semiconductor diode having the aforementioned inter-terminal capacitance in the DTTB band. By configuring the capacitive reactance element 61 in parallel with the additional device 15, the increase in insertion loss of power from the substrate input section A to the circuit input section B can be suppressed.

[0083] In addition, in the reactance regulating device 16 only utilizes Figure 6B When the inductive element 62 is configured as shown, if the power input from the substrate input section A contains a DC component, the inductive element 62 will short-circuit between the line 13 and the ground section. Therefore, in applications where the input power may contain a DC component, such as... Figure 6C As shown, by connecting the DC cut-off capacitor 63 in series with the inductive element 62, it is possible to maintain the additional functionality of the electronic components based on the inductive element 62 while preventing short circuits. In this case, the DC cut-off capacitor 63 can be disposed between the inductive element 62 and the ground, or it can be disposed between the inductive element 62 and the line 13.

[0084] Furthermore, the additional device 15 and the reactance adjustment device 16 can be equipped with various devices or circuits corresponding to the type of electrical stress. For example, various devices or circuits can be used. Figure 6D The Zener diode 64 shown Figure 6E The typical semiconductor diode 65 shown is... Figure 6F The TVS diode shown is 66, or... Figure 6G The variable resistor 67 shown, or a circuit with equivalent functionality, is also shown.

[0085] The Zener diode 64 is a device that outputs a certain voltage even when the current changes. Unlike the conventional semiconductor diode 65, which is used in the forward direction, the Zener diode 64 is used in the reverse direction. The TVS diode 66 is a device that absorbs a high transition voltage by rapidly changing its resistance from high to low, thereby outputting a lower voltage. The variable resistor 67 is a device with non-linear current characteristics, designed to guide surge current to ground when a surge current that momentarily exceeds the steady-state condition flows through it.

[0086] Furthermore, the reactance regulating device 16 can also be constructed using a conductor pattern along with the circuit. For example, Figure 7 As shown, the auxiliary device 15 and the reactance pattern 71 can be connected in parallel between the line 131, which is composed of a conductor pattern, and the grounding portion 132. The width, thickness, and length (distance between the line 131 and the grounding portion 132) of the reactance pattern 71 are set such that the impedance is a complex conjugate relationship with respect to the inter-terminal capacitance of the auxiliary device 15. The shape of the reactance pattern 71 is not limited to the linear pattern shown in the figure; it can also be a non-linear pattern, or a combination of linear and non-linear patterns.

[0087] <Component Configuration>

[0088] Next, the configuration and structure of each component in the antenna device 30 will be described. Figure 8 This is a schematic diagram showing an example of the configuration of the antenna device 30. The antenna device 30 includes an antenna base 1 and an antenna housing 2 made of radio wave transmissive components that covers the antenna base 1 from above. A receiving space is formed by the antenna base 1 and the antenna housing 2, and the receiving space is watertightly sealed. The antenna section 11 and the circuit board 12 described above are disposed within this receiving space. A mounting part 3 for mounting the antenna device 30 to a vehicle roof or the like is provided on the antenna base 1.

[0089] The circuit board 12 is fixed to the portion corresponding to the mounting portion 3 of the antenna base 1. A feed line F, composed of a coaxial cable, a rod-shaped conductor, or a wire-shaped conductor, is connected between the antenna section 11 and the board input portion A on the circuit board 12. In this example, the circuit board 12 is positioned in front of the antenna section 11 (facing left in the figure) from a top viewpoint (viewpoint from the antenna housing 2 looking at the antenna base 1). Furthermore, Figure 8 The example shown is in Figure 1 Antenna device 10 Figure 2 This is also common in antenna device 20. The difference between antenna device 10 and antenna device 20 and antenna device 30 is that the circuit board 12 of antenna device 10 and antenna device 20 does not contain additional components 15 or reactance adjustment devices 16. Furthermore, the arrangement of the circuit board 12 is not limited to the example where it is positioned in front of the antenna section 11 from the above-mentioned upward viewpoint. The circuit board 12 can simply be positioned below the antenna section 11 from a side viewpoint, which is a viewpoint orthogonal to the upward viewpoint. Additionally, the circuit board 12 does not need to be positioned directly below the antenna section 11; for example, it can be positioned in a location where the board is not covered by the antenna section when viewed from above.

[0090] [Second Implementation]

[0091] Next, the second embodiment of the present invention will be described. Figure 9 This is a schematic diagram showing an example of the configuration of the antenna device 40 according to the second embodiment. Components that have the same function as those shown in the first embodiment are labeled with the same reference numerals. The antenna device 40 has a circuit board 12 containing... Figure 2 The antenna device 20 shown has an auxiliary device 15 connected in series with the ground portion, and a reactance adjustment device 16 with the same polarity as the auxiliary device 15 is inserted and connected to the ground portion.

[0092] The series impedance of the reactance regulating device 16 is set to be the same as or greater than the series impedance of the auxiliary device 15. As a result, the impedance between line 13 and the grounding part increases, making it impossible for power to flow. Therefore, the increase in insertion loss between the substrate input part A and the circuit input part B can be suppressed.

[0093] In this example, the additional device 15 is the same as in the first embodiment, which is a semiconductor diode, and the inter-terminal capacitance is also 7pF, as in the first embodiment. On the other hand, the reactance adjustment device 16 in the second embodiment is a surface-mount capacitor, and a surface-mount capacitor with a capacitance of 5pF is used.

[0094] like Figure 9 The diagram illustrates the conditions for counteracting impedance variations in line 13 caused by the additional devices 15 and 16, and suppressing or reducing increases in insertion loss, when the additional devices 15 and 16 are connected in series. For ease of explanation, the conductor resistance values ​​of each device 15 and 16 are set to sufficiently small, negligible values.

[0095] Series impedance is calculated using |Z|=√{(R)} 2 +(jX) 2 The reactance of the additional device 15 when connected in series at a frequency of 595MHz is -j38.3 (Ω). As mentioned above, the conductor resistance R can be ignored. Therefore, the impedance of the additional device 15 when connected in series is 38.3Ω. Similarly, the reactance of the reactance regulating device 16 is -j53.6Ω, and the impedance is 53.6Ω. From these results, it can be seen that the impedance of the reactance regulating device 16 is higher than that of the additional device 15.

[0096] From a component configuration perspective, the reactance regulating device 16 is preferably positioned as close as possible to the location where the additional device 15 is located. The wiring from the additional device 15 to the reactance regulating device 16 contains inductance or capacitance; therefore, shorter wiring better suppresses the effects of inductance or capacitance. Simulation results demonstrate that, as described above, by positioning the reactance regulating device 16 within 1 / 10 of the wavelength of the upper limit frequency of the DTTB band from the location where the additional device 15 is located, the increase in insertion loss is suppressed.

[0097] Furthermore, in the second embodiment, a chip capacitor is used as the reactance adjustment device 16, but it is not limited to this. Other devices with capacitance in the DTTB band or conductor patterns described later may also be used.

[0098] Next, the antenna characteristics of the antenna device 40 of the second embodiment will be explained. Figure 10A This is a Smith chart showing the impedance traces in antenna devices 20 and 40. Figure 10A In the diagram, solid line 901 represents the impedance trajectory in antenna device 20, and dashed line 902 represents the impedance trajectory in antenna device 40. Figure 10B These are the VSWR characteristic diagrams for antenna devices 20 and 40. Figure 10B In the diagram, the vertical axis represents VSWR, the horizontal axis represents frequency [MHz], the solid line 911 represents the VSWR characteristics in the antenna device 20, and the dotted line 912 represents the VSWR characteristics in the antenna device 40 of the second embodiment.

[0099] like Figure 10A As shown, the impedance of antenna device 20 is capacitive in the DTTB band, and its trajectory 901 lies in the lower half of the Smith chart. The impedance of antenna device 40 is also capacitive in the DTTB band, and its trajectory 902 lies in the lower half of the Smith chart. However, when a patch capacitor is used as the reactance adjustment device 16 in antenna device 40, the impedance trajectory 902 of antenna device 40 becomes closer to the horizontal axis than the impedance trajectory 901 of antenna device 20, achieving matching compared to the case with only the additional device 15.

[0100] In addition, such as Figure 10B As shown by solid line 911, the VSWR in the DTTB band of antenna device 20 increases along with the frequency, with a minimum value of 2.7 and a maximum value of 4.3. On the other hand, as... Figure 10B As shown by the dotted line 912, although the VSWR of antenna device 40 increases along with the frequency, the minimum value of VSWR is 1.6 and the maximum value is 1.9, which is a significant improvement over antenna device 20.

[0101] The same tendency is observed regarding insertion loss characteristics. That is, Figure 11 This is a graph illustrating the insertion loss characteristics of antenna devices 20 and 40. In this graph, the insertion loss of antenna device 10 is set to 0 dB. In the graph, the solid line 1001 represents the insertion loss (dB) of antenna device 20, and the dashed line 1002 represents the insertion loss (dB) of antenna device 40. The insertion loss of antenna device 20 is -1 dB to -2.1 dB in the DTTB band. In contrast, the insertion loss of antenna device 40 is significantly lower than that of antenna device 20 in the DTTB band, ranging from -0.2 dB to -0.4 dB. Therefore, antenna device 40 exhibits reduced insertion loss compared to antenna device 20.

[0102] [Third Implementation]

[0103] The third embodiment of the present invention will be described. Figure 12 This is a schematic diagram showing an example of the configuration of the antenna device 50 according to the third embodiment. This antenna device 50 replaces the... Figure 9 The reactor regulating device 16 shown is composed of capacitive reactance elements, while the reactor regulating device 16a is composed of inductive reactance elements.

[0104] In this example, a surface-mount inductor with an inductance of approximately 47nH at the center frequency of the DTTB band is used as the inductive element. However, other inductive elements or conductor patterns described later that provide the same inductance in the DTTB band can also be used.

[0105] In the third embodiment, the series impedance of the reactance regulating device 16a is also set to be the same as or greater than the series impedance of the auxiliary device 15. Calculating the series impedance of the reactance regulating device 16a at a frequency of, for example, 595MHz using the formula for series impedance, yields +j175.4Ω, which is higher than the series impedance of the auxiliary device 15 (38.3Ω).

[0106] Next, the antenna characteristics of the antenna device 50 of the third embodiment will be explained. Figure 13A This is a Smith chart showing the frequency characteristics of antenna devices 20 and 50. In the figure, the solid line 1201 represents the impedance trajectory in antenna device 20, and the dashed line 1202 represents the impedance trajectory in antenna device 50. Figure 13B This is a VSWR characteristic diagram of antenna device 20 and antenna device 50 of the third embodiment. In this diagram, the vertical axis is VSWR and the horizontal axis is frequency (MHz). The solid line 1211 represents the VSWR characteristic of antenna device 20, and the dashed line 1212 represents the VSWR characteristic of antenna device 50 of the third embodiment.

[0107] like Figure 13A As shown, the impedance of antenna device 20 is capacitive in the DTTB band, and its trajectory 1201 is located in the lower half of the Smith chart. On the other hand, the impedance of antenna device 50 is inductive in the DTTB band, and its trajectory 1202 is located in the upper half of the Smith chart, becoming closer to the horizontal axis compared to the impedance trajectory of antenna device 20.

[0108] In addition, such as Figure 13B As shown, the VSWR in antenna device 20 and antenna device 50 increases along with the frequency, with a minimum value of 2.7 and a maximum value of 4.3. Conversely, the VSWR in antenna device 50 decreases along with the frequency, with a maximum value of 1.7 and a minimum value of 1.0.

[0109] Figure 14A graph is provided to illustrate the insertion loss characteristics of antenna devices 20 and 50. In this graph, the insertion loss of antenna device 10 is set to 0 dB. In the graph, solid line 1301 represents the insertion loss of antenna device 20. In antenna device 20, the insertion loss is greater than -1 dB, and it increases with increasing frequency, reaching a maximum of -2.1 dB. Dashed line 1302 represents the insertion loss of antenna device 50. The insertion loss of antenna device 50 is -0.3 dB to -0.1 dB in the DTTB band, thus reducing insertion loss.

[0110] In the antenna device 40 of the second embodiment, one end of the auxiliary device 15 is connected to the line 13 connecting the substrate input section A and the electronic components, and the other end is connected to one end of the reactance adjustment device 16, the other end of which is grounded. Similarly, in the antenna device 50 of the third embodiment, one end of the auxiliary device 15 is connected to the line 13 connecting the substrate input section A and the electronic circuit 14, and the other end is connected to one end of the reactance adjustment device 16a, the other end of which is grounded. However, the same effect can be obtained by interchanged arrangements of the reactance adjustment device 16 (or reactance adjustment device 16a) of the auxiliary device 15.

[0111] [Fourth Implementation]

[0112] The fourth embodiment of the present invention will be described. Figure 15 This is a schematic diagram showing a configuration example of the antenna device 60 according to the fourth embodiment. The difference between this antenna device 60 and the embodiments described so far is that one end of the reactance adjustment device 16 is connected to the line 13 that connects the substrate input section A and the electronic circuit 14, and the other end is connected to one end of the auxiliary device 15, and the other end of the auxiliary device 15 is connected to the ground section.

[0113] That is, the positions of the additional device 15 and the reactance adjustment device 16 are interchanged. The reactance adjustment device 16 is a 5pF patch capacitor, just like the antenna device 40. In the antenna device 60, the reactance adjustment device 16 can also be a capacitor, an inductor, or a device that connects a capacitor and an inductor in parallel.

[0114] Figure 16A This is a Smith chart showing the impedance traces in antenna devices 20 and 60. In the chart, the solid line 1501 represents the impedance trace in antenna device 20, and the dashed line 1502 represents the impedance trace in antenna device 60. Figure 16BThis is a VSWR characteristic diagram of antenna device 20 and antenna device 60. In the diagram, the vertical axis represents VSWR, the horizontal axis represents frequency [MHz], the solid line 1511 represents the VSWR characteristic of antenna device 20, and the dotted line 1512 represents the VSWR characteristic of antenna device 60.

[0115] like Figure 16A As shown, the impedance of antenna device 20 is capacitive in the DTTB band, and its trajectory, as shown by solid line 1501, lies in the lower half of the Smith chart. The impedance of antenna device 60 is also capacitive in the DTTB band, and its trajectory, as shown by dashed line 1502, lies in the lower half of the Smith chart, the same as antenna device 20. However, by connecting reactance adjustment device 16 to line 13 and in series with additional device 15, the impedance trajectory 1502 in antenna device 60 is located closer to the horizontal axis than that in antenna device 20.

[0116] In addition, such as Figure 16B As shown by solid line 1511, the VSWR in antenna device 20 increases along with the frequency, with a minimum value of 2.7 and a maximum value of 4.3. On the other hand, as... Figure 16B As shown by solid line 1512, the VSWR in antenna device 60 increases along with the frequency, but the VSWR and its variation are smaller than those in antenna device 20, with a minimum value of 1.6 and a maximum value of 1.9.

[0117] Figure 17 This is a graph illustrating the insertion loss characteristics of antenna device 20 and antenna device 60 in the fourth embodiment. In this graph, the insertion loss of antenna device 10 is set to 0 dB. In the graph, the solid line 1601 represents the insertion loss characteristic of antenna device 20, and the dashed line 1602 represents the insertion loss characteristic of antenna device 60. The insertion loss of antenna device 20 in the DTTB band is -1 to -2.1 dB, and the insertion loss of antenna device 60 in the DTTB band is -0.2 to -0.4 dB. Thus, it can be seen that antenna device 60 reduces power insertion loss compared to antenna device 20. Furthermore, Figure 17 Insertion loss characteristics 1602 and Figure 11 The insertion loss characteristics 1002 are almost identical. Therefore, it can be concluded that antenna device 60 and antenna device 40 obtain the same insertion loss characteristics.

[0118] [Fifth Implementation]

[0119] The fifth embodiment of the present invention will now be described. In the description up to this point, capacitive and inductive components utilizing surface-mount elements or conductor patterns have been described as reactance adjustment devices 16 and 16a. In the fifth embodiment, an example is described where a semiconductor element such as a diode is used as the reactance adjustment device 16b.

[0120] Figure 18 This is a schematic diagram showing an example of the configuration of the antenna device 70 according to the fifth embodiment. The reactance adjustment device 16b uses a semiconductor element. As shown, in the antenna device 70, the auxiliary device 15 and the reactance adjustment device 16b are connected in series. According to this configuration, it is possible to achieve the function of eliminating electrical stress by utilizing the auxiliary device 15, and also to reduce insertion loss by utilizing the reactance adjustment device 16b.

[0121] Figures 19A to 19D An alternative configuration example of the reactance regulating device 16b is shown. Figure 19A This configuration consists of a capacitor 181, which is a reactance regulating device 16b, connected in series with the additional device 15. Figure 19B It is a configuration in which an inductor 182, which serves as a reactance adjustment device 16b, is connected in series with the additional device 15. Figure 19C It is a configuration in which a diode 183, which serves as a reactance adjustment device 16b, is connected in series with the additional device 15. Figure 19D It is configured such that a TVS diode 184, which serves as a reactance adjustment device 16b, is connected in series with the additional device 15.

[0122] Alternatively, other forms of the reactance adjustment device 16b, such as filters that allow only the DTTB band to pass through or band-stop filters that block high-frequency components of external noise or static electricity, can also suppress insertion loss in the DTTB band. The filter can be constructed from electronic components or wiring patterns.

[0123] Figure 20A as well as Figure 20B This is an example diagram illustrating the connection of the reactance regulating device 16. Figure 20A It is configured to be connected in series in the order of additional device 15, capacitor 191, and inductor 192. Figure 20B It is a configuration in which a capacitor 180 and an inductor 192 are connected in series with the additional device 15 in parallel. Based on these configurations, insertion loss in the DTTB band can be suppressed.

[0124] The reactance regulating devices 16, 16a, and 16b, similar to those in the first embodiment, can also be constructed using conductor patterns along with the circuit. For example, as... Figure 21As shown, the configuration can also be such that the other end of the auxiliary device 15, which is connected to the line 131 composed of a conductor pattern, is connected to the ground portion 132 using a reactance pattern 211. The width, thickness, and length (distance between the other end of the auxiliary device 15 and the ground portion 132) of the reactance pattern 211 are set to an impedance value equal to or greater than the inter-terminal capacitance of the auxiliary device 15. Furthermore, the polarity of the reactance pattern 211 relative to the auxiliary device 15 is not particularly limited. The shape of the reactance pattern 211 is not limited to the linear pattern shown in the figure; it can also be a non-linear pattern, or a combination of linear and non-linear patterns.

[0125] [Sixth Implementation]

[0126] In embodiments 1 to 5, an example was described in which an additional device 15 and a reactance adjustment device 16 were disposed on the input side of the circuit board 12, that is, between the board input section A and the circuit input section B. This is because the additional device 15 needs to protect the electronic components of the electronic circuit 14 from the electrical stress caused by the power input mainly through the antenna section 11.

[0127] However, electrical stress can sometimes be generated on the output side of electronic circuit 14. That is, in vehicle-mounted antenna devices, external electronic devices, such as system units, are sometimes connected to the output side of electronic circuit 14.

[0128] The system unit supplies the DC voltage for antenna driving to the antenna section 11 via the circuit board 12, and receives DTTB band signals (RF signals) from the circuit board 12. In vehicle-mounted antenna devices, the DC voltage for antenna driving is supplied by the vehicle battery; therefore, the DC voltage sometimes fluctuates due to engine start / stop or vehicle driving status. This DC voltage fluctuation becomes electrical stress relative to the circuit board 12, and particularly relative to the electronic circuit 14. In the sixth embodiment, an example is described where an additional device 15 for eliminating this electrical stress and a reactance adjustment device 16 paired with the additional device 15 are provided.

[0129] Figure 22This is a schematic diagram showing a configuration example of the antenna device 80 according to the sixth embodiment. In this antenna device 80, an auxiliary device 15 and a reactance adjustment device 16 are arranged in parallel on the output side of the circuit board 12, that is, between the circuit output section C and the board output section D. Furthermore, the board output section D is also a part that connects to external electronic devices such as system units; therefore, the board output section D is also called an external connection section D that serves as an interface with external electronic devices. The auxiliary device 15 and the reactance adjustment device 16 are connected in parallel. That is, one end of the line 17 connecting the circuit output section C and the board output section D is connected to the auxiliary device 15, and the other end of the auxiliary device 15 is grounded. One end of the line 17 is also connected to the reactance adjustment device 16, and the other end of the reactance adjustment device 16 is grounded. The aforementioned system unit 18 is connected to the board output section D.

[0130] Figure 23 This is a schematic diagram showing a configuration example of the antenna device 90, which is a variation of the sixth embodiment. In this antenna device 90, the auxiliary device 15 and the reactance adjustment device 16 are connected in series in that order, and the other end of the reactance adjustment device 16 is grounded. Other configurations are similar to... Figure 22 same.

[0131] In the configuration of these antenna devices 80 and 90, the same effect as that of antenna devices 30 and 40 can be achieved. That is, antenna devices 80 and 90 maintain the stress relief effect of the additional device 15 and suppress the increase of insertion loss.

[0132] Reference Figures 24A-24C This section describes a specific configuration example of the additional device 15 and the reactance adjustment device 16 in the antenna device 90. Figure 24A This is an example of connecting a Zener diode 2201, which is an additional device 15, and a TVS (transition voltage suppression) diode 2202, which is a reactance regulation device 16, in series.

[0133] The Zener diode 2201 operates when a DC voltage applied from system unit 18 exceeds the maximum rated voltage of the electronic components on circuit board 12. However, the inter-terminal capacitance of the Zener diode 2201 is typically in the tens to hundreds of pF range. Therefore, when using only the Zener diode 2201 as an add-on device 15 in the DTTB band, the signal level (RF signal) output from circuit board 12 to system unit 18 is significantly attenuated. Therefore, in Figure 24A In the example configuration shown, the TVS diode 2202 is connected in series as a reactance adjustment device 16 relative to the Zener diode 2201.

[0134] At frequencies with the DTTB band, the inter-terminal capacitance of Zener diode 2201 is 275pF, and the inter-terminal capacitance of TVS diode 2202 is 0.35pF. Therefore, when Zener diode 2201 and TVS diode 2202 are connected in series, the inter-terminal capacitance of 0.35pF is very small and can suppress RF signal attenuation.

[0135] Furthermore, the TVS diode 2202 functions as an overvoltage protection component. Therefore, in addition to its role as a reactance regulating device 16, it also has the advantage of protecting electronic components from electrical stresses such as static electricity generated during handling or processing in the production line of the antenna device 90 or circuit board 12. Figure 24A The diagram illustrates a configuration where a Zener diode 2201 and a TVS diode 2202 are connected in series. In this example, the operating voltage of the protection element is increased by connecting the Zener diode and the TVS diode in series. Other configurations are also shown. Figure 24B This illustrates an example of increasing the operating voltage of a protection element by configuring two TVS diodes in series. Figure 24A as well as Figure 24B In the example, because the operating voltage of the protection element increases, it is possible to obtain the advantage of being able to prevent faults caused by the supplied DC voltage or ripple voltage.

[0136] Figure 24C It is Figure 24A The example shown is a Zener diode 2201 and a TVS diode 2202 packaged in a container P10. The container P10 has an input terminal P11 and an output terminal P12. One end of the Zener diode 2201 is connected to the input terminal P11, and the other end is connected to one end of the TVS diode 2202. The other end of the TVS diode 2202 is connected to the output terminal P12.

[0137] In this way, by encapsulating the Zener diode 2201 and the TVS diode 2202 within a single container P10, the manufacturing process is simplified compared to embedding them separately in the antenna device 90. Furthermore, replacement becomes easier. Moreover, this packaged product can be manufactured as a standalone protective device. In this case, it can be used not only in the antenna device 90 but also in other electronic devices, enabling a wider range of applications for the invention.

[0138] Furthermore, the configuration encapsulated within a container P10 is not limited to... Figure 24A For example, targeting Figure 24B The examples, as well as the additional device 15 and reactance regulating device 16 described so far, can also be constructed using this package.

[0139] Explain the antenna characteristics of antenna device 90. Figure 25 This is a graph illustrating the insertion loss characteristics of the antenna device 90. Insertion loss is the insertion loss from the substrate output section D on the circuit board 12 in the DTTB band to the circuit output section C. In this graph, the insertion loss of the antenna device 10 is set to 0 dB. In the graph, the solid line 2301 represents the insertion loss in an example where only the Zener diode 2201 is inserted as an additional device 15 in the antenna device 90, with a maximum loss of -29.9 dB.

[0140] On the other hand, in the figure, the dashed line 2302 represents the insertion loss in an example where the Zener diode 2201 and the TVS diode 2202 are connected in series in the antenna device 90, and the maximum insertion loss is 0 dB. The results show that by connecting the Zener diode 2201 and the TVS diode 2202 in series, the insertion loss is significantly suppressed.

[0141] Furthermore, the same application can also be made in embodiments 2 through 6. Figure 8 Examples of the configuration of each component are shown. Furthermore, in the description of embodiments 1 to 6, the frequency band used is set to the DTTB band. However, any frequency band in which the reactance component of the auxiliary device 15 becomes too large to be ignored—that is, a frequency band in which the reactance component of the auxiliary device 15 affects the operation of the electronic circuit 14—is acceptable. This invention can be applied not only in the DTTB band but also in other high-frequency bands, such as the microwave band or higher. Alternatively, it can be applied in the FM band, below the microwave band. Hereinafter, an example of an embodiment applied to the FM band will be described.

[0142] [Seventh Implementation]

[0143] The seventh embodiment of the present invention will be described. Here, an example will be described in which an electronic circuit for the FM band is added in addition to the electronic circuit for the DTTB band. Figure 26 This is a schematic diagram showing a configuration example of the antenna device 100 according to the seventh embodiment. In this antenna device 100, the FM circuit 2430 and the DTTB circuit 2440 are provided on a circuit board 2412. In the figure, the antenna section 11 is connected to the circuit board 2412 via the board input section A, and branches into the FM circuit 2430 and the DTTB circuit 2440.

[0144] In the FM circuit 2430, the line further branches, one side connecting to the circuit input section B on the input side of the electronic circuit 2414a, and the other side connecting to the reactance adjustment device 2416. In the DTTB circuit 2440, it is connected to the electronic component 2414b via the filter 2420. In this case, the FM circuit 2430 is viewed as having a filter added in parallel with the DTTB circuit 2440. Therefore, the impedance on the DTTB circuit 2440 side (DTTB circuit impedance) imparts electrical stress relative to the FM circuit 2430. That is, the DTTB circuit impedance becomes a variable factor in the impedance of the input side of the FM circuit 2430.

[0145] Therefore, in the seventh embodiment, one end of the reactance adjustment device 2416, which has a complex conjugate relationship with the impedance of the parallel-added DTTB circuit, is connected to the input side of the electronic circuit 2414a of the FM circuit 2430, and the other end is connected to the ground.

[0146] By configuring it in this way, the reactance regulating device 2416 operates in a manner that cancels out the electrical stress applied to the electronic circuit 2414a of the FM circuit 2430 and suppresses the influence of impedance fluctuations on the input side of the FM circuit 2430 caused by the impedance of the DTTB circuit. Therefore, it can achieve the same effect as the first to sixth embodiments.

[0147] [Eighth Implementation]

[0148] The eighth embodiment of the present invention will be described. Here, an example will be described where the reactance regulating device 2416 described in the seventh embodiment is arranged on the output side of the FM circuit 2430. Figure 27 This is a schematic diagram showing a configuration example of the antenna device 110 according to the eighth embodiment. Figure 26 The same elements are labeled with the same reference numerals.

[0149] In this antenna device 110, a system unit 2518 (the same unit as the system unit 18 described above) is connected to the board output section D. The system unit 2518 supplies the DC voltage for antenna driving to the antenna section 11 (not shown) via the circuit board 2512, and receives signals (RF signals) in the DTTB band and signals (FM signals) in the FM band from the circuit board 2512. Since the DC voltage for antenna driving of the antenna device 110 is supplied by the vehicle battery, the DC voltage may fluctuate due to engine start / stop or vehicle driving status. This fluctuation of DC voltage results in electrical stress relative to the respective components of the DTTB circuit 2440 and FM circuit 2530 on the circuit board 2512.

[0150] Therefore, in the 8th embodiment, one end of the reactance regulating device 2416 is connected to the circuit output section C and the substrate output section D on the output side of the electronic circuit 2414a of the FM circuit 2530, and the other end of the reactance regulating device 2416 is connected to the ground section.

[0151] In this antenna device 110, the reactance adjustment device 2416 operates by eliminating the electrical stress applied to the electronic circuit 2414a of the FM circuit 2530 and suppressing the influence of impedance fluctuations on the output side of the FM circuit 2530 caused by the DTTB circuit 2440 (DTTB circuit impedance). Therefore, it can achieve the same effect as in the seventh embodiment.

[0152] [Other Implementation Methods]

[0153] In addition to being implemented as an antenna device 30, the present invention can also be implemented as a protection device for an electronic circuit, which includes: an electronic circuit; an auxiliary device that applies electrical stress to the constituent components of the electronic circuit, which is connected between the input side or output side of the electronic circuit and a ground portion; and a reactance adjustment device that cancels the reactance of the auxiliary device in the operating frequency band.

[0154] Or, such as Figure 22 As shown, the device, after being packaged with additional components and reactance adjustment devices, can also be implemented as a protection device for electronic circuits.

[0155] <Key Points of Each Implementation Method>

[0156] Based on the descriptions of the various embodiments above, the following configurations and their resulting effects are derived, for example.

[0157] (1) The antenna device comprises: an antenna section; a substrate to which the antenna section is connected; an electronic circuit provided on the substrate; and a reactance adjustment device that cancels out the reactance of the electrical stress applied to the constituent components of the electronic circuit in the frequency band of use, the substrate having a substrate input section that serves as an input interface between the antenna section and the antenna section, and the reactance adjustment device being provided between the substrate input section and the electronic circuit and connected to a ground section.

[0158] The reactance that causes the electrical stress is, for example, the reactance of an additional device connected between the input portion of the substrate and the ground portion, which eliminates the electrical stress applied to the components of the electronic circuit.

[0159] According to this configuration, since the reactance that becomes electrical stress is canceled by the reactance adjustment device, the electrical stress is eliminated and the increase in insertion loss of signal (power) from the antenna section to the electronic circuit is suppressed.

[0160] Furthermore, the substrate has a substrate input section that serves as an input interface between the antenna section and the electronic circuit, and a circuit input section that serves as an input interface between the electronic circuit. The reactance adjustment device can also be configured to be located between the substrate input section and the electronic circuit. According to this configuration, the increase in signal (power) insertion loss from the antenna section to the electronic circuit is suppressed.

[0161] (2) An antenna device comprising: an antenna section; a substrate to which the antenna section is connected; an electronic circuit provided on the substrate; and a reactance adjustment device for canceling reactance that is applied to the constituent components of the electronic circuit in the operating frequency band; the substrate having an external connection section for connection to an external electronic device, and the reactance adjustment device being provided between the electronic circuit and the external connection section and connected to a grounding section.

[0162] The reactance that causes the electrical stress is, for example, the reactance of an additional device connected between the circuit output and the grounding portion, which eliminates the electrical stress applied to the components of the electronic circuit.

[0163] According to this configuration, since the reactance adjustment device cancels out the reactance that becomes electrical stress, the electrical stress is eliminated, and the increase in the insertion loss of the signal (power) from the external electronic device to the electronic circuit is suppressed.

[0164] Furthermore, the substrate has a circuit output section that serves as the output side of the electronic circuit and an external connection section that connects to an external electronic device. The reactance regulating device can also be configured to be located between the circuit output section and the external connection section and connected to a ground section. With this configuration, the increase in signal (power) insertion loss from the external electronic device to the circuit output section of the electronic circuit is suppressed.

[0165] (3) In the antenna device, the impedance of the reactance adjustment device is in a complex conjugate relationship with the impedance of the additional device in the operating frequency band. According to this configuration, the reactance of the additional device is canceled to zero by the reactance adjustment device, thereby matching the impedance of the antenna section with that of the electronic circuit.

[0166] (4) In the antenna assembly, the additional device and the reactance adjustment device are connected in parallel. In particular, (5) in the antenna assembly, the additional device and the reactance adjustment device are arranged with an interval of less than 1 / 10 of the wavelength of the operating frequency. According to this configuration, the increase in inductance and capacitance of the line caused by the presence of the reactance adjustment device is suppressed.

[0167] (6) In the antenna assembly, the reactance regulating device is connected in series with respect to the additional device. In particular, (7) in the antenna assembly, the additional device is a Zener diode and the reactance regulating device is a TVS diode. According to this configuration, not only is the insertion loss from the antenna section to the circuit output section of the electronic circuit greatly suppressed, but the protection of the electronic components is also more robust by utilizing the TVS diode, which also functions as an overvoltage protection component.

[0168] (8) In the antenna assembly, the additional components and the reactance adjustment components are encapsulated in a single container. This configuration simplifies the manufacturing process compared to individually embedding each component into the antenna assembly. Furthermore, replacement is easier.

[0169] (9) In the antenna device, the operating frequency band is a high-frequency band, such as a frequency band above the microwave band, where the reactance component of the additional device affects the operation of the electronic circuit. According to this configuration, the influence (increase) of the reactance of the additional device can be eliminated more significantly.

[0170] (10) The protection device for the electronic circuit includes: an electronic circuit; an additional device attached to protect the constituent components of the electronic circuit from electrical stress, which is connected between the input side or output side of the electronic circuit and a ground portion; and a reactance regulating device that cancels the reactance of the additional device in the operating frequency band. Based on this configuration, the application scenarios of the present invention can be expanded.

Claims

1. An antenna device comprising: Antenna section; A substrate to which the antenna section is connected; Electronic circuitry disposed on the substrate; Additional devices for relieving electrical stress applied to the constituent components of the electronic circuit; and A reactance adjustment device that cancels out the reactance of the additional device in the operating frequency band. The substrate has a substrate input section that serves as an input interface between the substrate and the antenna section, a circuit input section that serves as an input interface for the electronic circuit, and lines connecting the substrate input section and the circuit input section. The additional device and the reactance adjustment device are disposed on the line between the input section of the substrate and the electronic circuit, and are connected to the ground section.

2. An antenna device comprising: Antenna section; A substrate to which the antenna section is connected; Electronic circuitry disposed on the substrate; and Additional devices for relieving electrical stress applied to the constituent components of the electronic circuit; and A reactance adjustment device that cancels out the reactance of the additional device in the operating frequency band. The substrate has an external connection portion for connecting to an external electronic device, a circuit output portion that serves as an output interface for the electronic circuit, and lines connecting the external connection portion and the circuit output portion. The additional device and the reactance adjustment device are disposed on the line between the electronic circuit and the external connection part and are connected to the ground part.

3. The antenna device according to claim 1, wherein, The reactance of the additional device is connected between the input portion of the substrate and the ground portion.

4. The antenna device according to claim 2, wherein, The reactance of the additional device is connected between the electronic circuit and the grounding portion.

5. The antenna device according to claim 3 or 4, wherein, The impedance of the reactance regulating device is in a complex conjugate relationship with the impedance of the additional device in the operating frequency band.

6. The antenna device according to claim 3 or 4, wherein, The additional device is connected in parallel with the reactance adjustment device.

7. The antenna device according to claim 6, wherein, The additional device and the reactance adjustment device are configured with an interval of less than 1 / 10 of the wavelength of the operating frequency.

8. The antenna device according to claim 3 or 4, wherein, The reactance regulating device is connected in series with respect to the additional device.

9. The antenna device according to claim 8, wherein, The additional device is a Zener diode, and the reactance adjustment device is a TVS diode.

10. The antenna device according to claim 3 or 4, wherein, The additional device and the reactance adjustment device are encapsulated in a container.

11. The antenna device according to claim 1 or 2, wherein, The frequency band used is the high-frequency band in which the reactance of the additional device affects the operation of the electronic circuit.

12. The antenna device according to claim 11, wherein, The high-frequency band refers to the frequency band above the microwave band.

13. The antenna device according to claim 1 or 2, wherein, The electronic circuit includes active components.

14. A protection device for an electronic circuit, comprising: Electronic circuits; A substrate in which the electronic circuitry is provided; Additional devices are added to protect the components of the electronic circuit from electrical stress, and are connected between the input or output side of the electronic circuit and the ground. as well as A reactance adjustment device that cancels out the reactance of the additional device in the operating frequency band. The reactance of the additional device is the reactance to eliminate the electrical stress. The substrate has: A substrate input section that serves as the input interface for the substrate; The substrate output section serves as the output interface of the substrate; as well as At least one of the lines connecting the input section of the substrate to the input side of the electronic circuit and the lines connecting the output side of the electronic circuit to the output section of the substrate. The reactance regulating device is installed on the line and connected to the grounding part.

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