JPH0720961Y2 - Shared antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to an antenna shared device in, for example, a base station of a car telephone.

2. Description of the Related Art FIG. 11 is a system diagram showing an example of a conventional antenna shared device, in which CAV _{1 to} CAV ₁₆ are coaxial resonators and each n is connected to a common line CL.
Each branch connection is made to branch points OP _{1 to} OP ₁₆ provided at intervals of λg / 2 (n is an arbitrary positive integer, λg is a guide wavelength).

Problems to be Solved by the Invention In the above-mentioned conventional antenna common use device, since only one coaxial resonator can be branched and connected to each branch point of the common line CL, it is necessary to increase the number of communication paths. There is no choice but to increase the number of branch points, and as a result, an increase in the common line length cannot be avoided.

When the common line becomes long, the amount of phase deviation of the transmission signal becomes large and the transmission characteristic deteriorates.Therefore, there is a limit to the length of the common line and the limit of the number of communication paths that does not cause the deterioration of the transmission characteristic. Is about 32 channels.

Means for Solving Problems In the antenna duplexer of the present invention, the problem of each branch point of the coaxial line forming the common line is selected as nλg / 2, and the coaxial resonator or the coaxial terminal of the branch device is attached / detached to / from each branch point. The present invention is characterized in that two sets of branch holes that can be freely inserted are provided.

Action In the antenna common use device of the present invention, since two sets of branch holes are provided at each branch point of the common line, at least two coaxial resonators can be branched and connected to one branch point, and the common line length can be shortened. You can do it.

Embodiment FIG. 1 is a diagram showing a main part of an embodiment of the present invention, and FIG. 2 is an end view of a portion AA in FIG. The outer conductor CL _O and the inner conductor CL _I are coaxially arranged via a spacer S _L made of an insulating material. H _O11 ,
H _O12 , H _O21 and H _O22 are external branch holes, SP ₁₁ and SP, which are drilled at the locations corresponding to the branch points of the outer conductor CL _O of the common line CL.
₁₂ , SP ₂₁ and SP ₂₂ are cylindrical plug seats, and have external branch holes H _O11 ,
The outer branch holes are coaxially attached to the peripheral portions of H _O12 , H _O21, and H _O22 . H _I11 , H _I12 , H _I21, and H _I22 are internal branch holes, which are bored in the inner conductor CL _I of the common line CL at a location corresponding to the branch point, and each central axis has a corresponding spigot SP. It is aligned with each central axis of _{11 to} SP ₂₂ .

The distance between the branch points on the common line CL is nλg /
Is 2.

Next, CAV ₁ is a coaxial resonator, with the outer conductor CA _O and the inner conductor C
A _I , a coaxial terminal CT _T1 for connecting a transmitter or a receiver, a coupling loop LP _T , a resonance frequency fine adjustment element FA ₁ , a branch coupling coaxial terminal CT _{B1, a} coupling loop LP _{B, and the} like.

The total electrical length of the coupling loop LP _B and the branch connection coaxial terminal CT _B1 is formed to be ¼ wavelength or an odd multiple thereof.

CAV ₂ , CAV ₃ and CAV ₄ are also coaxial resonators, CT _{T2 to} CT _T4 are coaxial terminals for connecting a transmitter or a receiver, FA _{2 to} FA ₄ are fine adjustment elements for resonance frequency, and CT _{B2 to} CT _B4 are These are coaxial terminals for branch connection, and the internal configuration of these coaxial resonators is the same as that of the coaxial resonator CAV ₁ .

Connect the coaxial terminal CT _B1 for branch connection of the coaxial resonator CAV ₁ to the common line CL
Coaxial terminal for branch connection when it is inserted into the connector seat SP ₁₁
With external conductors CT _O of CT _B1 is connected to the outer conductor CL _O common line CL, the tip end portion of the inner conductor CT ₁ branch connection coaxial terminal CT _B1 is bored to the inner conductor CL _I common line CL It is inserted into the internal branch hole H _I11 and the coaxial resonator CA is installed at the branch point of the common line CL.
V ₁ is branched and connected.

Similarly, by inserting the branch connecting coaxial terminals CT _{B2 to} CT _B4 of the coaxial resonators CAV ₂ , CAV ₃ and CAV ₄ into the sockets SP _{12 to} SP ₂₂ , the coaxial resonators are connected to the branch point of the common line CL. Can be connected to.

FIG. 1 illustrates the case where two coaxial resonators are connected to each branch point through two plug seats provided at one branch point of the common line CL. As shown in the main part,
By interposing two branching devices BJ _{11 to} BJ ₂₂ between SP _{11 to} SP ₂₂ and the branch connecting coaxial terminal of the coaxial resonator, four coaxial resonators CAV ₁ are provided at each branch point of the common line CL. To CAV ₄
And CAV _{5 to} CAV ₈ can be branched and connected, and as shown in FIG. 4 by interposing 4 branchers, 8 coaxial resonators can be branched and connected to one branch point. You can

Since FIG. 4 is a drawing corresponding to the drawing of the common line CL side viewed from the left side of FIG. 3, the four connecting points are connected to the branch point via the spigot seat SP ₁₁ and the four branch device. Coaxial resonator CAV _{1 to}
Only four coaxial resonators CAV _{9 to} CAV ₁₂ and a common line CL, which are connected to the branching point through the CAV ₄ , the plugging seat SP ₂₁ and the 4 branching device, are shown. Resonator CAV _{1 to
4} coaxial resonators CAV _{5 to} CA symmetrically connected to CAV ₄
All four coaxial resonators CAV _{13 to} CAV _16, etc. which are symmetrically connected to V ₈ and the coaxial resonators CAV _{9 to} CAV ₁₂ are not shown.

2 branching device in FIG. 3 and 4 described in FIG.
As the branching device, a branching device having a two-branching circuit or a four-branching circuit formed of, for example, a microstrip line is used, and when any one of the branching devices is used, a terminal (ground point) of the coupling loop in the coaxial resonator is used. Is formed so that the length from the branching point of the common line CL via the branch connecting coaxial terminal of the coaxial resonator and the branching device is 1/4 or an odd multiple thereof in terms of electrical length.

The above has exemplified the case where each of the outer conductors CL _O and the inner conductors CL _I forming the common line CL has a rectangular cross section, but one of the conductors has a rectangular cross section and the other conductor has a cross section. The present invention can be implemented by forming both the inner and outer conductors in a circular cross section.

Also, the case where the resonator branched and connected to the common line CL is composed of a coaxial resonator has been described above. However, if the resonator uses a loop as an input / output coupling element connected to the common line CL, the resonator is a coaxial resonator. Besides, the present invention can be implemented by using a rectangular waveguide resonator, a circular waveguide resonator, a dielectric resonator, or the like.

In FIG. 1, FIG. 3 and FIG. 4, 2 in the common line CL is shown.
Only the branch points and the coaxial resonator parts connected to these branch points are shown, but as shown in the system diagram in FIG. 5, one common line CL connected to the common terminal T _COM is used. nλ
Coaxial resonators CAV _{1 to} CAV by branching and connecting two coaxial resonators to branch points P _{1 to} P ₁₆ provided at intervals of g / 2.
It can be configured 32 antenna sharing device of a communication channel consisting of _32, as shown in FIG. 6, two common lines CL ₁ and CL ₂
Branch points P _{1 to} P ₈ and P _{9 to} P at intervals of nλg / 2
₁₆ is provided, and two coaxial resonators are branched and connected at each branch point, and the two common lines CL ₁ and CL ₂ are connected to the common terminal T _COM.
Even when configured to be connected in parallel with each other, it is possible to configure an antenna shared device of 32 communication paths.

In the configuration shown in FIG. 5 or FIG. 6, as shown in FIG. 3, two branching devices are provided between each branching point and the coaxial terminal of the coaxial resonator to form a shared antenna device for 64 communication paths. It is possible to construct an antenna shared device with 128 communication paths by interposing 4 branching devices.

Further, as shown in FIG. 7, each of the _two common lines CL ₁ and CL ₂ connected in parallel to the common terminal T _COM has four branch points P _{1 to} P ₄ and P _{5 at} intervals of nλg / 2. To P ₈ are provided and eight coaxial resonators are branched and connected to each branching point through four branching devices, whereby an antenna shared device of 64 communication paths can be configured.

Of course, the common lines CL, CL ₁ and CL ₂ and the branch points P _{1 to} P ₁₆ in FIGS. 5 to 7 have the same configurations as those described in FIG.

Effect of the Invention In the antenna common use device of the present invention, since at least two resonators can be branched and connected to each branch point of the common line, in the case of the same number of communication paths, the length of the common line is at least approximately equal to that of the conventional device. It can be shortened to 1/2 and can be further shortened by using a branching device together, so good electrical characteristics can be maintained even when the number of communication paths is increased.

FIG. 8 is a curve diagram showing an example of attenuation characteristics between the common terminal T _COM in the antenna common use device of the present invention configured as shown in FIG. 5 and the connection terminals of the transmitter (receiver) receivers in each coaxial resonator. The axis is the transmission frequency F (MHz), and the vertical axis is the attenuation-ATT
(DB).

FIG. 9 is a curve diagram showing an example of the attenuation characteristic of the antenna common line device of the present invention configured as shown in FIG. 6, and FIG. 10 is an example of the attenuation characteristic of the antenna common line device of the present invention configured as shown in FIG. In the curve diagrams shown, all the curve diagrams show better characteristics than the attenuation characteristics of the conventional device shown in FIG.

Note that FIG. 12 shows an example of the attenuation characteristics of the antenna common line device having 64 communication paths, which is configured by connecting the four conventional devices shown in FIG. 11 in parallel to the four common terminals.

The horizontal and vertical axes in FIGS. 9, 10, and 12 are the same as in FIG.

8 to 10 are attenuation characteristic curve diagrams when resonators are mounted in all the branch holes of the common line in FIGS. 5 to 7. If the device is not mounted, the open branch hole may be left untouched without being covered with a lid made of a conductor plate, for example, and a sudden change in impedance may occur at this branch point. There is almost no risk of adversely affecting the transmission characteristics of other communication paths such as radiation loss due to leakage.

[Brief description of drawings]

FIG. 1 is a view showing a main part of an embodiment of the present invention, FIG. 2 is an end view taken along the line AA of FIG. 1, and FIGS. 3 and 4 are main parts of another embodiment. 5 to 7 are system diagrams showing an example of the entire configuration of the antenna shared device of the present invention, and FIGS. 8 to 8.
FIG. 10 is a curve diagram showing an example of attenuation characteristics of the antenna common use device of the present invention, FIG. 11 is a system diagram showing a conventional device, and FIG. 12 is a characteristic curve diagram of the conventional device, CL, CL ₁ and CL ₂ : Common line, C
L _O : common line outer conductor, CL _I : common line inner conductor, S
_L : Spacer, H _{O11 to} H _O22 : External branch hole, SP _{11 to} SP
₂₂ : Connector, H _{I11 to} H _I22 : Internal branch hole, CAV _{1 to} CAV
₆₄ : coaxial resonator, CA _O : outer conductor of coaxial resonator, CA _I : inner conductor of coaxial resonator, CT _{B1 to} CT _B4 : coaxial terminal for branch connection, CT _O : outer conductor of coaxial terminal for branch connection, CT _I : Inner conductor of branch connection coaxial terminal, CT _{T1 to} CT _T4 : Coaxial terminals for connection of transmitter or receiver, LP _B and LP _T : Coupling loop, FA ₁
To FA ₄ : fine adjustment element of resonance frequency, BJ _{11 to} BJ ₂₂ : 2 branching device, P _{1 to} P ₁₆ : branching point, T _COM : common terminal, OP _{1 to} OP
₁₆ : It is a branch point.

Claims (1)

[Scope of utility model registration request] 1. A pair of branch holes into which coaxial terminals are detachably fitted are provided at each branch point of a coaxial line, and the interval between the branch points is selected to be 1/2 of the guide wavelength or an integral multiple thereof. An antenna common line device comprising a common line formed as described above.