JP3414383B2 - Transmission line, integrated circuit and transmitting / receiving device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission line formed on a dielectric plate, an integrated circuit provided with the dielectric plate, or
The present invention relates to a transmission / reception device such as a radar device or a communication device including the integrated circuit.

[0002]

2. Description of the Related Art Conventionally, a waveguide type transmission line has been constructed on a dielectric substrate to be integrated with the dielectric substrate.
JP-A-6-53711 and JP-A-10-7510
8 are disclosed.

In the waveguide line, a plurality of conducting holes (through holes) connecting the conductor layers are provided in two rows on a dielectric substrate having two or more conductor layers, and the conductor layers and the conducting holes of the two layers are provided. Between the two rows of (1) and (2) are operated as a waveguide (dielectric-filled waveguide). In addition to the above-mentioned configuration, the dielectric waveguide line and the wiring board of the sub-device are electrically connected to the via hole between the two main conductor layers and on both outsides of the via hole (conduction hole). A conductor layer is formed.

[0004]

[Problems to be Solved by the Invention]
The current path that acts as a wall in the plane along the vertical direction (direction perpendicular to the plane of the dielectric substrate) of the waveguide is
Since there are only through holes or via holes, there is a problem that current concentrates on the through holes or via holes and conductor loss increases. Further, due to the through hole or via hole formed in the direction perpendicular to the surface of the dielectric substrate, the current flows only in the direction perpendicular to the surface of the dielectric substrate, and the current does not flow in the diagonal direction.
There is a problem that good transmission characteristics cannot be obtained as compared with a general waveguide or a dielectric-filled waveguide.

An object of the present invention is to provide a waveguide type transmission line on a dielectric plate, which has the effect of improving productivity and the effect of integration by integration with a wiring board, and also improves the transmission characteristics. An object of the present invention is to provide a transmission line, an integrated circuit including the transmission line, and a radar device.

[0006]

The transmission line of the present invention comprises:
At least one surface of the dielectric plate is provided with a continuous protruding portion having a convex cross-section, electrodes are formed on both surfaces of the dielectric plate including the outer surface of the protruding portion, and The distance between the electrodes in the thickness direction is set to be equal to or more than a half wavelength of the wavelength in the dielectric at the operating frequency, and a plurality of through holes are formed on both sides of the ridge to electrically connect the electrodes formed on both sides of the dielectric plate. It is configured by arranging holes.
In this way, the continuous raised portion having a convex cross section of the dielectric plate acts as a part of the dielectric-filled waveguide type transmission line.

Further, in the transmission line of the present invention, the distance between the through holes in the direction along the raised portion is set to be equal to or less than a half wavelength of the dielectric medium wavelength at the used frequency. As a result, the arrayed through holes form the wall surface of the waveguide equivalently at the used frequency and the higher frequency band.
Suppress unnecessary transmission modes.

Further, in the transmission line of the present invention, the distance between the through holes arranged on both sides of the raised portion in the direction crossing the raised portion is set to one wavelength or less of the wavelength in the dielectric. This makes it difficult to convert to the parallel plate mode at the used frequency.

Further, in the transmission line of the present invention, the distance between the electrodes in the raised portion is set to be equal to or less than the wavelength of the wavelength in the dielectric at the operating frequency, and the width of the raised portion and the through hole in the direction crossing the raised portion. The distance between them is set to be equal to or less than a half wavelength of the wavelength in the dielectric at the used frequency. This enables transmission in a single mode in the used frequency band.

Further, in the transmission line of the present invention, the corners of the convex cross section are rounded. This alleviates the current concentration at the edge portion of the electrode and reduces the conductor loss.

Further, in the transmission line according to the present invention, the side surface of the raised portion is tapered so as to be farther from the dielectric plate. This improves the productivity of the transmission line.

In the integrated circuit of the present invention, by forming a plurality of transmission lines on the dielectric plate having the transmission line of the above-mentioned structure or by mounting electronic parts,
An integrated circuit including the transmission line is configured.

In the integrated circuit of the present invention, the base material of the dielectric plate is ceramic. This improves heat resistance, enables mounting of surface mount components by the collective reflow soldering method, and improves productivity.

Further, the transmission / reception device of the present invention is configured such that the transmission line in the integrated circuit is a transmission line for transmitting a transmission signal and a reception signal, and an oscillator and a mixer are provided. As a result, low power consumption and high sensitivity due to low loss are achieved. For example, a radar device with detection ability and low power consumption is obtained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the transmission line according to the first embodiment will be described with reference to FIGS. 1A is a perspective view of the transmission line, and FIG. 1B is a sectional view thereof. In FIG. 1, reference numeral 1 is a dielectric plate, and a ridge 2 having a convex cross section and being continuous in the direction perpendicular to the cross section is formed on a part of the dielectric plate. Electrodes 3 are provided on both surfaces of the dielectric plate 1 including the outer surfaces (both side surfaces and upper surface) of the raised portion 2. Also,
A plurality of through holes 4 are formed on both sides of the raised portion 2 so as to electrically connect between the electrodes 3 formed on both surfaces of the dielectric plate 1 along the extending direction of the raised portion 2. Here, the width W of the raised portion 2 is set to 1/2 or less of the wavelength in the dielectric at the operating frequency, and the height H from the lower surface of the dielectric plate to the upper surface of the raised portion is set in the dielectric at the operating frequency. It is set to 1/2 or more of the wavelength.

FIG. 2A shows the distribution of the electromagnetic field in the cross section of the plane perpendicular to the extending direction of the raised portion 2. Further, (B) shows the distribution of the electromagnetic field in the perspective view of the transmission line.

With this structure, the plurality of arranged through holes 4 equivalently form the wall surface of the waveguide, so that the two side surfaces of the raised portion 2 facing each other are the H surface, the upper surface of the raised portion 2 and the dielectric. Electromagnetic waves propagate in a mode conforming to the TE10 mode in which the lower surface of the plate 1 is the E surface.

FIG. 3 shows the electric field vector of this transmission line as
The thickness of the dielectric plate 1 other than the raised portion 2 is taken into consideration. (A) shows an electric field vector in a direction perpendicular to the electromagnetic wave propagation direction and parallel to the surface direction of the dielectric plate. (B) shows the electric field vector in the direction perpendicular to the electromagnetic wave propagation direction and perpendicular to the surface of the dielectric plate. This transmission line is considered to be a superposition of the electric field vector shown in (A) and the electric field vector shown in (B). Therefore, the composite electric field vector is expressed as shown in (C).

The mode having the electric field vector shown in FIG. 3B is a higher-order mode of the parallel plate mode, and is a mode causing radiation loss. The cutoff frequency of this mode is the interval P between the two rows of through holes arranged.
Since it is determined by x and the dielectric constant of the dielectric, if the wavelength in the dielectric in the frequency band used is represented by λ, then Px <λ to make it difficult to convert to the unnecessary parallel plate mode in the frequency band used. Is possible. The distance between the through holes in the electromagnetic wave propagation direction (P in (A) of FIG.
With respect to z) as well, if the wavelength is equal to or less than a half wavelength of the wavelength in the dielectric in the used frequency band, the parallel plate mode is not excited, so that the radiation loss due to conversion of the used propagation mode into the parallel plate mode does not occur.

That is, in order to make it difficult to convert to the parallel plate mode, if the width W of the raised portion is a half wavelength, the distance from the side surface of the raised portion to the through hole is 1/4.
It should be set below the wavelength.

It should be noted that the electrode spacing H in the thickness direction of the dielectric at the portion where the raised portion shown in FIG. 1B is formed.
Is not less than a half wavelength and not more than 1 wavelength of the wavelength in the dielectric at the used frequency, and the width W of the raised portion 2 and the through hole 4 are
Since the mode orthogonal to the use mode becomes a cutoff condition by setting the interval of half wavelength or less, TE1
It is possible to transmit in a single mode, which is a mode based on the 0 mode. Therefore, even if the bend portion is provided on the raised portion 2, a loss due to mode conversion or a loss due to spurious emission does not occur.

Next, FIG. 4 shows the configuration of the transmission line according to the second embodiment. In the first embodiment, two rows of through holes facing each other are arranged on both sides of the raised portion formed on the dielectric plate, but in the second embodiment, the through holes are arranged in a plurality of rows. In the example shown in FIG. 4A, two rows of through holes are arranged in a zigzag pattern on both sides of the raised portion 2. Further, in the example shown in (B), three rows of through holes are arranged on both sides of the raised portion 2. By thus multiplexing the row of through holes, it is possible to further suppress radiation from the transmission line portion of the parallel plate mode propagating in the dielectric plate to the outside or incidence from the outside to the transmission line.

Next, the structure of the transmission line according to the third embodiment will be described with reference to FIGS. Figure 3 is the third
It is a perspective view of the transmission line which concerns on embodiment of FIG. In this example, a ridge 2 having a bend structure is formed on the dielectric plate 1, and through holes 4 are arranged on both sides of the ridge 2.

FIG. 6 shows specific dimensions of each part and transmission characteristics resulting therefrom. Here, the relative permittivity of the dielectric plate is 7.0 and the radius r of the line center of the bend part is 2.0 [m
m], the diameter of the through holes 4 is 0.1 [mm], the array pitch of the through holes 4 is 0.4 [mm], and the dimensions of other parts are the values shown in FIG. 6B. Four
Is formed on one side in three rows, for a total of six rows.

FIG. 6C shows S11 and S under the above conditions.
21 characteristics are shown. Even if a bend with a small radius of curvature is provided in this way, low insertion loss and low reflection characteristics can be obtained by making the transmission line a single-mode transmission line conforming to the TE10 mode.

Next, FIG. 7 is a sectional view showing the structure of the transmission line according to the fourth embodiment. In this example, the dielectric plate 1
The corners of the raised portion 2 formed in 1 are rounded as indicated by R. With this structure, current concentration on the electrode edge is relaxed, conductor loss is reduced, and low insertion loss characteristics are obtained.

The raised portion of the transmission line shown in FIG.
It can be formed by a sandblast method.

FIG. 8 is a sectional view of a transmission line according to the fifth embodiment. In this example, the ridge 2 having a convex cross-section is formed on the dielectric plate 1, and both side surfaces of the ridge 2 are formed on the dielectric plate 1.
It has a taper shape that tapers away from it. When the dielectric plate having such a raised portion is manufactured by mold molding or injection molding, the mold release property between the molded body and the mold is improved, and thus the productivity is improved.

Next, the structure of a radar device as an example of an integrated circuit and a transmitter / receiver using the same will be described with reference to FIGS. 9 and 10. FIG. 9 is a perspective view of the dielectric plate 1 viewed from the mounting surface side of an electronic component, and FIG. 10 is an equivalent circuit diagram thereof. The dielectric plate 1 is formed with continuous ridges having a convex cross-section on the lower surface side in the figure, electrodes are formed on both sides of the dielectric plate, and a plurality of ridges are formed on both sides of the ridges along the ridges. A transmission line is configured by arranging through holes.

Since FIG. 9 shows the side of the dielectric plate 1 on which the electronic component is mounted, no ridge is shown, but the arrangement pattern of the through holes shows the arrangement shape of the transmission line. That is, roughly G1, G2, G3, G
Five transmission lines indicated by 4 and G5 are formed.

A VCO (voltage controlled oscillator) connected to a coplanar line is provided on the upper surface of the dielectric plate 1 in the figure. The coplanar line is coupled to the transmission line indicated by G1. An amplifier circuit using an FET is provided between the transmission lines G1 and G2. A slot antenna is formed at the tip of the transmission line G3, and a transmission signal is radiated from the slot antenna in a direction perpendicular to the dielectric plate 1. A directional coupler is formed by the portions of the transmission lines G2 and G5 that are close to each other. The signal distributed by the directional coupler is coupled as a local signal to the coplanar line to which one diode of the mixer circuit is connected. Further, a circulator is formed in the central portion of the transmission lines G2, G3, G4 branched into a Y shape. This circulator is configured by arranging a resonator made of a disk-shaped ferrite plate and arranging a permanent magnet that applies a static magnetic field in a direction perpendicular to the ferrite plate, but they are omitted in FIG. ing. The signal received from the slot antenna via this circulator is coupled to the coplanar line to which the other diode of the mixer circuit is connected via the transmission line G4. The two diodes of the mixer circuit act as a balanced mixer circuit, and are output to an external circuit via a balanced line having a matching passive component in the middle.

FIG. 10 is a block diagram of the radar device. In FIG. 10, the oscillation signal by the VCO is AMP
The signal is amplified by and is given to the antenna ANT as a transmission signal through the directional coupler CPL and the circulator CIR. The received signal from the circulator CIR and the local signal from the directional coupler CPL are given to the mixer MIX, and the mixer outputs the intermediate frequency signal IF.

As described above, by using the transmission line having a low transmission loss, it is possible to obtain a radar device having high power efficiency, low power consumption, and high ability to detect a target.

In the above example, the radar device is taken as an example, but if the transmission signal is transmitted to the communication device on the partner side and the transmission signal from the communication device on the partner side is received, the same applies. And a communication device can be configured.

[0035]

According to the present invention, a waveguide type transmission line with low transmission loss can be constructed by using a dielectric plate, and an apparatus in which parts are mounted on the flat surface of the dielectric plate is easily constructed. it can.

Further, according to the transmission line of the present invention, the spacing in the array direction of the through holes is set to be equal to or less than the half wavelength of the wavelength in the dielectric at the used frequency, whereby the unnecessary transmission mode is further suppressed.

Further, according to the transmission line of the present invention, the distance between the through holes arranged on both sides of the raised portion is set to be equal to or less than 1 wavelength of the wavelength in the dielectric, so that the parallel plate mode is set at the used frequency. Since it becomes difficult to convert and there is no loss due to it, a transmission line with even lower loss can be obtained.

Further, according to the transmission line of the present invention, the interval between the electrodes in the raised portion is set to 1 wavelength or less of the wavelength in the dielectric at the working frequency, and the width of the raised portion and the direction crossing the raised portion are set. By setting the spacing between through holes to be less than half the wavelength of the dielectric medium wavelength at the operating frequency, it is possible to transmit in single mode in the operating frequency band, and loss due to mode conversion in the bend part may occur. Without
The degree of freedom of the arrangement pattern of the transmission line is improved.

Further, according to the transmission line of the present invention, by rounding the corners of the cross-sectional shape of the raised portion, the current concentration at the edge portion of the electrode is relaxed and the conductor loss is further reduced.

Further, according to the transmission line of the present invention, the side surface of the raised portion is tapered so as to be farther from the dielectric plate, whereby the productivity of the transmission line is improved and the cost is reduced. You can

Further, according to the integrated circuit of the present invention, the loss can be reduced by forming a plurality of transmission lines on the dielectric plate on which the transmission line having the above structure is formed. In particular, by forming one surface of the dielectric plate as a flat surface, it becomes easy to form a line by a conductor pattern and mount an electronic component.

Further, according to the integrated circuit of the present invention, by using ceramic as the base material of the dielectric plate, it becomes possible to mount the surface mount components by the batch reflow soldering method, and the productivity is improved, so that the cost is low. Can be realized.

Further, according to the transmitting / receiving device of the present invention, the transmission line in the integrated circuit is a transmission line for transmitting a transmission signal and a reception signal, and further, an oscillator and a mixer are provided to reduce power consumption. And high sensitivity can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view and a sectional view showing a configuration of a transmission line according to a first embodiment.

FIG. 2 is a diagram showing an example of an electromagnetic field distribution of the transmission line.

FIG. 3 is a diagram showing details of an electric field vector of the transmission line.

FIG. 4 is a perspective view of a transmission line according to a second embodiment.

FIG. 5 is a perspective view of a transmission line according to a third embodiment.

FIG. 6 is a diagram showing an example of dimensions and transmission characteristics of each part of the transmission line.

FIG. 7 is a sectional view of a transmission line according to a fourth embodiment.

FIG. 8 is a sectional view of a transmission line according to a fifth embodiment.

FIG. 9 is a diagram showing configurations of an integrated circuit and a radar device according to a sixth embodiment.

FIG. 10 is a block diagram of the radar device.

[Explanation of symbols] 1-dielectric plate 2-Protrusion 3-electrode 4-through hole

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Claims (9)

(57) [Claims] 1. A dielectric plate is provided on at least one surface thereof with a continuous ridge having a convex cross section, and electrodes are formed on both surfaces of the dielectric plate, including the outer surface of the ridge, and the ridge is formed. In, the distance between the electrodes in the thickness direction of the dielectric plate,
A transmission line having a half wavelength or more of a wavelength in the dielectric at a use frequency, and further having a plurality of through holes arranged on both sides of the raised portion to electrically connect between the electrodes formed on both surfaces of the dielectric plate. 2. The transmission line according to claim 1, wherein the distance between the through holes in the direction along the raised portion is set to be equal to or less than a half wavelength of the wavelength in the dielectric material at the working frequency. 3. The transmission line according to claim 1, wherein the distance between the through holes arranged on both sides of the raised portion is equal to or less than one wavelength of the wavelength in the dielectric. 4. The distance between the electrodes in the thickness direction of the dielectric plate in the raised portion is set to 1 of the wavelength in the dielectric at the operating frequency.
4. The wavelength is equal to or less than the wavelength, and the width of the raised portion and the distance between the through holes in the direction crossing the raised portion are set to be equal to or less than a half wavelength of the wavelength in the dielectric at the used frequency.
The transmission line described in. 5. The transmission line according to claim 1, wherein the corners of the convex cross section are rounded. 6. The transmission line according to claim 1, wherein a side surface of the raised portion is tapered so that the side surface thereof is tapered away from the dielectric plate. 7. An integrated circuit comprising a plurality of transmission lines or electronic components mounted on the dielectric plate having the transmission line according to claim 1. Description: 8. The integrated circuit according to claim 7, wherein the base material of the dielectric plate is ceramic. 9. A transmission / reception device comprising the transmission line in the integrated circuit according to claim 7 or 8 as a transmission line for transmitting a transmission signal and a reception signal, and further including an oscillator and a mixer.