JP6264316B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device that transmits or receives high-frequency signals such as microwaves and millimeter waves.

  In an antenna device composed of a transmission antenna and a reception antenna, in order to minimize the transmission path to the mixer of the millimeter wave signal received by the reception antenna, a microstrip line is provided as a feed line on one surface of the resin substrate. A technique is known in which a receiving antenna and a transmitting antenna are formed and a mixer is mounted near the receiving antenna (see, for example, Patent Document 1).

  In addition, in an antenna device composed of a transmission antenna and a reception antenna, a technique for reducing leakage and wraparound of transmission power from the transmission antenna to the reception antenna by providing a radio wave absorber between the transmission antenna and the reception antenna in the radome It has been known.

JP 2010-273049 A

  However, in the conventional antenna device shown in Patent Document 1, radio waves radiated from a transmission antenna or a transmission circuit leak into a reception system circuit such as a mixer or a low-noise amplifier, and interfere with the reception system circuit or cause noise. There is a problem of mixing.

  In order to reduce this radio wave interference, it is possible to provide a radio wave absorber between the transmission antenna and the mixer. However, the radio wave absorber has a problem that the manufacturing price is expensive and the manufacturing price of the antenna device is high.

  The present invention has been made to solve the problem, and a transmission antenna and a reception antenna, and a receiving circuit such as a mixer and a low noise amplifier are provided on the same surface of the substrate, and without using a radio wave absorber, An object is to suppress leakage of transmission radio waves from a transmission antenna to a reception circuit.

  An antenna device according to the present invention includes a transmission antenna that radiates a transmission radio wave, a reception antenna that receives a reflected wave of the transmission radio wave, a transmission circuit connected to the transmission antenna by a transmission antenna feed line, and a reception antenna feed line. A resin having a receiving circuit connected to the receiving antenna and connected to the transmitting circuit by a local signal line and having a conductor film mounted so as to surround the transmitting antenna, the receiving antenna, the transmitting circuit, and the receiving circuit Forming a substrate, a first compartment containing at least the transmitting circuit, and a second compartment containing at least the receiving circuit, and forming a partition between the first compartment and the second compartment; A radome having a conductor film formed therein and a groove surrounded by the conductor film in which the first and second compartments communicate with each other and in which the local signal line is disposed The provided, the width of the groove is obtained by the following half-wave of the radio wave leaking from the transmitting antenna feed line.

  According to the present invention, in an antenna device in which a transmission antenna, a reception antenna, a transmission circuit, and a reception circuit are arranged on the same surface of a resin substrate, the reception circuit can be changed from the transmission antenna and the transmission circuit without using a radio wave absorber. Leakage of radio waves transmitted to the can be suppressed.

1 is an upper cross-sectional view illustrating a configuration of an antenna device according to a first embodiment. FIG. 2 is a side cross-sectional view showing the configuration of the antenna device according to the first embodiment. 3 is a BB side cross-sectional view showing the configuration of the antenna device according to the first embodiment. FIG. It is a figure which shows the inner surface structure of the radome of the antenna apparatus by Embodiment 1. FIG. It is a figure which shows the peripheral part of the groove | channel which connects the compartment of the radome of the antenna apparatus by Embodiment 1. FIG.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of an antenna apparatus according to Embodiment 1 of the present invention. FIG. 2 is a side cross-sectional view showing the configuration of the antenna device according to the first embodiment, as viewed from the direction of arrows AA in FIG. 3 is a side cross-sectional view showing the configuration of the antenna device according to the first embodiment, viewed from the direction of the arrow BB in FIG. FIG. 4 is a diagram showing the inner surface structure of the radome of the antenna device according to the first embodiment, as viewed from the inner surface of the radome. FIG. 5 is a detailed view around the groove provided in the partition wall of the radome.

  In FIG. 1, the antenna device 10 includes a resin substrate 1 and a radome 50. The resin substrate 1 has an antenna mounting surface 60 constituting the transmitting antenna 2 and the receiving antenna 3 formed on the surface (the upper surface in FIG. 1) of the printed wiring board mounted on both sides.

  The resin substrate 1 is formed using a low-loss fluororesin having a small dielectric loss tangent (for example, a polytetrafluoroethylene substrate having a dielectric loss tangent tan θ = 0.0007 to 0.0020) so as to suppress transmission loss of high-frequency signals. It is configured by combining a plurality of base materials. A high frequency circuit mounting surface 70 is formed adjacent to the antenna mounting surface 60 of the resin substrate 1. On the high-frequency circuit mounting surface 70 of the resin substrate 1, the transmitting circuit 4 and the receiving circuit 5 are flip-chip mounted with a space therebetween. On the back surface of the resin substrate 1, one or a plurality of integrated circuits 9 such as a microcomputer and a memory are mounted. The integrated circuit 9 is connected to the transmission circuit 4 and the reception circuit 5 through the wiring pattern of the resin substrate 1 and the conductor vias, respectively.

  The transmission antenna 2 is composed of a plurality of antenna elements, and the plurality of antenna elements are arranged at a predetermined interval to form an antenna array. The transmission circuit 4 is connected to the transmission antenna feed line 6 of the transmission antenna 2. The receiving antenna 3 is composed of a plurality of antenna elements, and the plurality of antenna elements are arranged at a predetermined interval to form an antenna array. Further, the receiving antenna 3 is arranged from at least two or more antenna arrays. The reception circuit 5 is connected to a plurality of transmission antenna feed lines 7 in the reception antenna 3. The transmission circuit 4 is connected to the reception circuit 5 via a local signal line 8.

  The transmission circuit 4 includes an oscillator, a high output amplifier, a power distributor, and the like. The receiving circuit 5 includes a mixer, a low noise amplifier, and the like. The local signal line 8 connects between the oscillator of the transmission circuit 4 and the mixer of the reception circuit 5. Each antenna array of the reception antenna 3 is connected to a different mixer of the reception circuit 5 to constitute a different reception channel.

  A ground conductor 40 is formed on the outer peripheral edge of the surface of the resin substrate 1 so as to surround the antenna mounting surface 60 and the high-frequency circuit mounting surface 70. For example, the ground conductor 40 surrounds the transmitting antenna 2 and the receiving antenna 3 in a rectangular shape. The ground conductor 40 surrounds the transmission circuit 4 and the reception circuit 5 in a rectangular shape. A ground conductor 41 is formed along the outer periphery of the outer peripheral edge of the back surface of the resin substrate 1. On the inner layer of the resin substrate 1, a ground conductor 410 that forms a ground plane of the transmitting antenna 2 and the receiving antenna 3 is formed. The ground conductor 40 on the front surface of the resin substrate 1, the ground conductor 41 on the back surface, and the ground conductor 410 on the inner layer are connected to each other through the conductor via 55. The ground conductor 410 is formed with a conductor hole for passing through a conductor via (not shown) that connects the transmission circuit 4 and the receiver circuit 5 and the integrated circuit 9, and a conductor hole for passing through the conductor via 55, respectively. Yes.

  However, the ground conductor 40 has a gap 61 where there is no conductor and the dielectric surface is exposed on the surface of the portion through which the transmission antenna feed line 6 connecting the transmission antenna 2 and the transmission circuit 4 passes. Further, the ground conductor 40 is formed with a gap portion 62 where there is no conductor and the dielectric surface is exposed on the surface of the portion through which each transmission antenna feed line 7 connecting the reception antenna 3 and the reception circuit 5 passes. . Further, the ground conductor 40 is formed with a gap 63 where there is no conductor and the dielectric surface is exposed on the surface of the portion through which each antenna feed line 8 connecting the transmission circuit 4 and the reception circuit 5 passes.

In FIG. 4, the radome 50 is integrally formed from a plane portion 51, a side wall portion 52, and a partition wall portion 53. The flat part 51 is a rectangular plate shape. The planar portion 51 has a thickness and a thickness so that a radio wave having a desired transmission frequency transmitted from the transmission antenna 2 to the outside and a radio wave having a desired frequency incident from the outside and received by the reception antenna 3 are easily transmitted. The radome thickness is formed to be the radio wave matching thickness. The side wall portion 52 is erected so as to surround the entire circumference of the four sides of the flat portion 51. The partition wall portion 53 connects between the side wall portions 52 located on the opposite sides of the rectangular shape of the flat surface portion 51.
In FIG. 4, TX indicates a space in which the transmission antenna 2 and the transmission circuit 4 are accommodated, and RX indicates a space in which the reception antenna 3 and the reception circuit 5 are accommodated.

  Further, the radome 50 is formed with a plurality of compartments 45, 46, 47 and 48 surrounded by the side wall 52 and the partition wall 53. Here, the compartment 45 contains the receiving circuit 5, and the compartment 46 contains the transmitting circuit 4. The compartment 47 has the receiving antenna 3 arranged on the inner side, and the compartment 48 has the transmitting antenna 2 arranged on the inner side.

  The conductor film 20 is attached to the lower end surface of the side wall portion 52 of the radome 50 and the lower end surface of the partition wall 53 by a metallization technique such as metal vapor deposition. Further, the conductor film 20 is attached to the bottom surface and the inner surface of the wall surface of the compartment 45 and the compartment 46 of the radome 50 by a metallization technique such as metal vapor deposition. The conductor film 20 is connected to the ground via ground conductors 40 and 41.

Note that the bottom surfaces of the compartments 47 and 48 of the radome 50 do not have the conductor film 20 so that transmission radio waves transmitted from the transmission antenna 2 and reception radio waves received by the reception antenna 3 can pass therethrough.
Further, the partition wall 53 that separates the compartment 47 and the compartment 48 of the radome 50 from the side of the compartment 47 so that radio waves radiated from the transmitting antenna 2 to the space do not pass through and enter the receiving antenna 3 side. Alternatively, the conductor film 20 is provided on the wall on the compartment 48 side.

  The radome 50 includes a groove 11 that connects the space of the partition wall 45 and the space of the partition wall 46, a groove 12 that connects the space of the partition wall 46 and the space of the partition wall 48, and the space of the partition wall 45 and the space of the partition wall 47. Grooves 13 and 14 that are connected and communicated are formed.

  The radome 50 is disposed so that the conductor film 20 on the lower end surface is in contact with the upper surface of the conductor film 40 of the resin substrate 1 and is fixed by a fastening screw portion or an adhesive.

  Note that the radome 50 may be disposed on the upper surface of the resin substrate 1 so that the outer periphery of the radome 50 protrudes outside the outer periphery of the resin substrate 1 in order to maintain watertightness or prevent moisture from being mixed. In this case, by adhering the end face of the radome 50 to the resin case at the portion where the outer periphery of the radome 50 protrudes outward from the resin substrate 1, it is possible to maintain water tightness and prevent moisture from being mixed. In addition, at the portion where the outer periphery of the radome 50 protrudes outside the resin substrate 1, the end face of the radome 50 is pressed against the waterproof ring and fastened and fixed to the resin case so as to maintain water tightness and prevent moisture from entering. Also good.

  FIG. 5 is a view showing a peripheral portion of the groove connecting the compartments of the radome of the antenna device 10 according to the first embodiment, and shows a state where the radome 50 is in contact with the resin substrate 1. 4 and 5, the transmission antenna feed line 6 is disposed in the groove 12, the local signal line 8 is disposed in the groove 11, and the transmission antenna feed line 7 is disposed in the groove 13 or the groove 14.

  In FIG. 5, each of the grooves 11, 12, 13, and 14 is covered with the ground surface by the conductor film 20 on the upper surface and side surfaces. Each of the grooves 11, 12, 13, 14 is provided with a conductor via 55 around the lower part. The conductor film 20 covering each of the grooves 11, 12, 13, 14 is connected to the ground conductor 410 or the ground conductor 41 formed on the inner layer or the back surface of the resin substrate 1 via the conductor film 40 and the conductor via 55. The lower space is covered by the ground plane. Thus, the surrounding space of each of the grooves 11, 12, 13, and 14 is surrounded by the ground surface by the conductor film 20, the conductor via 55, the ground conductor 41, and the ground conductor 410.

Further, each groove 11, 12 has a groove width W for blocking the harmonics of the transmitted wave or the transmission frequency _{f 0} of the desired transmission frequency _{f 0} of the transmit antenna 2 (e.g. second harmonic) . For example, when the wavelength at the transmission frequency f ₀ is λ, the groove width W = λ / 2 or less or the groove width W = λ / 2 or less, so that it is below the cutoff frequency of the signal to be cut off (below the cutoff wavelength). The groove width W is set.

The antenna device 10 according to the first embodiment operates as follows.
A transmission radio wave is radiated from the transmission antenna 2, the transmission radio wave is reflected by an external target (target), returns to the antenna device side, and the reflected radio wave is received by the reception antenna 3.

  In the transmission circuit 4, the oscillator transmits a source signal having a desired frequency, the high-power amplifier amplifies the source signal, and feeds the transmission signal amplified to high output from the transmission antenna feed line 6 to the transmission antenna 2. . The transmission antenna 2 radiates transmission radio waves fed from the transmission antenna feed line 6. The transmission circuit 4 transmits a local signal obtained by distributing the power of the transmission signal from the local signal line 8 to the reception circuit 5. The receiving circuit 5 inputs the received radio wave received by the receiving antenna 3 to the receiving circuit 5. The receiving circuit 5 amplifies the received radio wave received by the receiving antenna 3 and frequency-mixes it with the local signal input from the local signal line 8 to generate a baseband down-converted signal. The transmission circuit 4 performs an operation process based on the bias power supply and control signal output from the integrated circuit 9. The receiving circuit 5 performs an operation process based on the bias power supply and control signal output from the integrated circuit 9. Further, the receiving circuit 5 sends a down-converted signal to the integrated circuit 9 and performs baseband signal processing such as analog-digital conversion and Fourier transform.

  When the antenna apparatus 10 according to the first embodiment is a radar apparatus, the integrated circuit 9 detects the target, the distance to the target, the extraction of the Doppler signal, the target angle measurement process, and the like based on the baseband signal processing result. Radar signal processing. Further, based on a plurality of reception signals received by the reception circuit 5, a phase difference between reception channels is obtained, and angle measurement processing is performed.

  Here, the transmission circuit 4, the transmission antenna feed line 6, and the local signal line 8 radiate leaked radio waves into the space. In particular, the transmission antenna feed line 6 radiates high-power radio waves amplified by the high-power amplifier of the transmission circuit 4. The leaked radio wave radiated into this space is reflected by the conductor film 20 and does not leak from the compartment 46 of the radome 50 into the compartment 47. Further, since the grooves 11, 12, 13, and 14 are set to the cut-off frequency, the leaked radio wave radiated into this space does not leak through the grooves 11, 12, 13, and 14.

In order to prevent the reflected signal in the compartment 46 from resonating, the size of the compartment 46 is an integral multiple of the wavelength λ of the transmission frequency f ₀ or a harmonic of the transmission frequency f ₀ (for example, a second harmonic) or a wavelength λ / 4. It is better not to be an odd multiple.

In addition, the conductive film 20 is not provided on the wall surface 90 of at least a part of the side wall portion 52 of the compartment 46. Here, the wall surface 90 of at least a part of the side wall portion 52 where the grooves 11 and 12 are not formed in the compartment 46 is a dielectric window where the conductor film 20 is not formed.
In this case, since the reflected signal in the compartment 46 leaks to the outside from the portion where the conductor film 20 is not attached, the reflected signal in the compartment 46 does not resonate. At this time, the signal leaking to the outside from the wall surface 90 wraps around, and the signals incident on the reception circuit 5, the transmission antenna feeder 7 and the reception antenna 3 decrease. For this reason, signals leaking from the transmission circuit 4, the transmission antenna feed line 6, and the local signal line 8 and entering the reception circuit 5, the transmission antenna feed line 7 and the reception antenna 3 are reduced.

  Further, since the conductor film 20 is provided on the partition wall 53 that separates the compartment 47 and the compartment 48 of the radome 50, the radio wave radiated from the transmitting antenna 2 to the space is received from the compartment 48 into the receiving antenna in the compartment 47. Leakage to 3 can be suppressed.

  When the signal intensity of the leaked radio wave from the transmission circuit 4 is small, the partition wall 53 that separates the compartment 46 and the compartment 48 may be removed. Further, when the intensity of the signal transmitted from the transmitting antenna 2 and reflected back from the outside or directly incident from the transmitting antenna 2 is low, the power supplied to the receiving antenna feeding line 7 or the receiving circuit 5 is small. The partition wall 53 that separates the chambers 47 may be removed.

  As described above, the antenna device 10 according to Embodiment 1 is connected to the transmission antenna 2 by the transmission antenna 2 that radiates transmission radio waves, the reception antenna 3 that receives reflected waves of the transmission radio waves, and the transmission antenna feeder 6. The transmission circuit 4 is connected to the reception antenna 3 by a reception antenna feed line 7, and the reception circuit 5 is connected to the transmission circuit 4 by a local signal line 8. The resin substrate 1 on which the conductive film 20 is mounted so as to surround the antenna 3, the transmission circuit 4, and the reception circuit 5, the first compartment 46 that houses at least the transmission circuit 4, and at least the reception circuit 5 are accommodated. The second compartment 45 is formed, the conductor film 20 is formed on the partition wall 53 between the first compartment 46 and the second compartment 45, and the first compartment 46 2 including a radome 50 formed with a groove 11 surrounded by a conductor film 20 in which the local signal line 8 is disposed, and the width of the groove 11 extends from the transmission antenna feed line 6. It is characterized in that the leaked radio wave has a half wavelength (λ / 2) or less.

  In addition, a transmission antenna 2 that radiates a transmission radio wave, a reception antenna 3 that receives a reflection wave of the transmission radio wave, a transmission circuit 4 connected to the transmission antenna 2 by a transmission antenna feed line 6, and a reception antenna feed line 7 And the receiving circuit 5 connected to the transmitting circuit 4 by the local signal line 8 and surrounds the transmitting antenna 2, the receiving antenna 3, the transmitting circuit 4, and the receiving circuit 5. Thus, the resin substrate 1 on which the conductor film 20 is mounted, the first compartment 46 that houses at least the transmission circuit 4, the second compartment 45 that houses the reception circuit 5, and the reception antenna 3 are housed. A third compartment 47 is formed, and a first partition 53 between the first compartment 46 and the second compartment 45 and a second partition 45 between the second compartment 45 and the third compartment 47 are formed. 2 leads to the partition walls 53 respectively The film 20 is formed, and the first groove 11 surrounded by the conductor film 20 in which the local signal line 8 is disposed in communication with the first compartment 46 and the second compartment 45, and the first A radome 50 having a second groove 13 and 14 formed in communication with the second compartment 45 and the third compartment 47 and surrounded by the conductor film 20 in which the receiving antenna feed line 7 is disposed. The antenna device in which the widths 11, 13, and 14 of the first and second grooves are equal to or less than a half wavelength of the radio wave leaking from the transmission antenna feed line. The first compartment 46 is covered with the conductor film 20 at the bottom and the wall surface.

  In addition, a transmission antenna 2 that radiates a transmission radio wave, a reception antenna 3 that receives a reflection wave of the transmission radio wave, a transmission circuit 4 connected to the transmission antenna 2 by a transmission antenna feed line 6, and a reception antenna feed line 7 And the reception circuit 5 connected to the transmission circuit 4 by the local signal line 8 so as to surround the transmission antenna 2, the reception antenna 3, the transmission circuit 4, and the reception circuit 5. The resin substrate 1 on which the conductor film 20 is mounted, the first compartment 46 for housing the transmission circuit 4, the second compartment 45 for housing the reception circuit 5, and the third compartment for housing the reception antenna 3. And a fourth partition 48 for accommodating the transmitting antenna 2 is formed, and the first partition 53 and the second partition between the first partition 46 and the third partition 47 are formed. Compartment 45 and third compartment 7, the third partition wall 53 between the first compartment 46 and the fourth compartment 48, and the fourth partition between the second compartment 45 and the fourth compartment 48. The conductor film 20 is formed on each of the partition walls 53, and the first compartment surrounded by the conductor film 20 in which the local signal line 8 is disposed through the second compartment 45 and the first compartment 46. A groove 11, second grooves 13, 14 surrounded by a conductor film 20 in which the second antenna 45 and the third compartment 47 communicate with each other and the receiving antenna feeder 7 is disposed; The first compartment 46 and the fourth compartment 48, and a radome 50 formed with the third groove 12 surrounded by the conductor film 20 in which the transmission antenna feed line 6 is disposed. The widths of the first, second, and third grooves 11, 13, 14, and 12 are equal to or less than a half wavelength of the radio wave that leaks from the transmission antenna feed line. The bottom and wall surfaces of the second and fourth compartments 45 and 48 are covered with the conductor film 20 and the side walls of the fourth compartment 48 where the first and third grooves 11 and 12 are not formed. At least a portion is a dielectric window in which the conductor film 20 is not formed.

  Thus, in the antenna device 10 in which the transmission antenna 2, the reception antenna 3, the transmission circuit 4, and the reception circuit 5 are arranged on the same surface of the resin substrate 1, the transmission antenna 2 and the transmission circuit are used without using a radio wave absorber. 4, leakage of the transmission radio wave to the receiving circuit 5 can be suppressed.

Embodiment 2. FIG.
In the radome 50 of the first embodiment, a resistive film may be used for all or part of the conductor film 20. By using a resistive film for the conductor film 20, radio waves radiated into the space from the transmission circuit 4, the transmission antenna feed line 6, and the local signal line 8 are attenuated in the compartment 46 of the radome 50, and Leakage radio waves incident on the chamber 47 are reduced. Further, by using a resistive film as the conductor film 20 on the inner surface of each groove 11, 12, 13, 14, the harmonics of the transmission frequency f ₀ passing through the grooves 11, 12, 13, 14 (for example, third harmonic, Double wave) can be suppressed.

  However, the partition wall 53 separating the compartment 47 and the compartment 48 of the radome 50 is preferably covered with a metal film so that radio waves radiated from the transmitting antenna 2 to the space do not pass.

  1 resin substrate, 2 transmitting antenna, 3 receiving antenna, 4 transmitting circuit, 5 receiving circuit, 6 transmitting antenna feed line, 7 transmitting antenna feed line, 8 local signal line, 9 integrated circuit, 10 antenna device, 11 groove, 12 groove , 13 groove, 14 groove, 20 conductor film, 40 conductor film, 45 compartment, 46 compartment, 47 compartment, 48 compartment, 50 radome, 53 partition.

Claims (4)

A transmission antenna that radiates transmission radio waves,
A receiving antenna for receiving the reflected wave of the transmission radio wave;
A transmission circuit connected to the transmission antenna by a transmission antenna feed line;
A receiving circuit connected to the receiving antenna by a receiving antenna feed line and connected to a transmitting circuit by a local signal line;
A resin substrate on which a conductor film is mounted so as to surround the transmission antenna, the reception antenna, the transmission circuit, and the reception circuit;
Forming at least a first compartment containing the transmitting circuit and a second compartment containing at least the receiving circuit, and forming a conductor film on a partition between the first compartment and the second compartment; A radome formed with a groove surrounded by a conductor film in which the first signal chamber and the second chamber communicate with each other and the local signal line is disposed;
With
The antenna device wherein the width of the groove is equal to or less than a half wavelength of the radio wave leaking from the transmission antenna feeder line. A transmission antenna that radiates transmission radio waves,
A receiving antenna for receiving the reflected wave of the transmission radio wave;
A transmission circuit connected to the transmission antenna by a transmission antenna feed line;
A receiving circuit connected to the receiving antenna by a receiving antenna feed line and connected to a transmitting circuit by a local signal line;
A resin substrate on which a conductor film is mounted so as to surround the transmission antenna, the reception antenna, the transmission circuit, and the reception circuit;
Forming at least a first compartment containing the transmitting circuit, a second compartment containing the receiving circuit, and a third compartment containing the receiving antenna; Conductive films are formed on the first partition between the compartments and on the second partition between the second and third compartments, respectively, and the first and second compartments are formed. The first groove surrounded by the conductor film in which the local signal line is disposed and the conductor film in which the reception antenna feed line is disposed in communication with the second compartment and the third compartment A radome formed with a second groove surrounded by
With
The antenna device wherein the width of the first and second grooves is equal to or less than a half wavelength of the radio wave leaking from the transmission antenna feed line.   3. The antenna apparatus according to claim 2, wherein the first compartment has a bottom surface and a wall surface covered with a conductor film. A transmission antenna that radiates transmission radio waves,
A receiving antenna for receiving the reflected wave of the transmission radio wave;
A transmission circuit connected to the transmission antenna by a transmission antenna feed line;
A receiving circuit connected to the receiving antenna by a receiving antenna feed line and connected to a transmitting circuit by a local signal line;
A resin substrate on which a conductor film is mounted so as to surround the transmission antenna, the reception antenna, the transmission circuit, and the reception circuit;
Forming a first compartment for housing the transmission circuit, a second compartment for housing the reception circuit, and a third compartment for housing the reception antenna, and a fourth compartment for housing the transmission antenna. Forming a first partition between the first compartment and the third compartment, a second partition between the second compartment and the third compartment, the first compartment and the first compartment. Conductive films are respectively formed on the third partition between the four compartments and on the fourth partition between the second and fourth compartments, and the second compartment and the first partition. The first antenna groove surrounded by the conductor film in which the local signal line is arranged through the chamber, the second compartment and the third compartment are communicated with the receiving antenna feed line. A second groove surrounded by the conductor film, and a third groove surrounded by the conductor film in which the transmission antenna feed line is arranged to communicate with the first compartment and the fourth compartment are formed. Redo And,
With
The width of the first, second, and third grooves is equal to or less than a half wavelength of the radio wave leaking from the transmission antenna feed line,
The bottom and wall surfaces of the second and fourth compartments are covered with a conductor film, and a conductor film is formed on at least a part of the side wall portion in the fourth compartment where the first and third grooves are not formed. Antenna device in which is not formed.

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