JPH02202203A - Antenna feeder - Google Patents

Abstract

PURPOSE:To easily and surely obtain the mechanical and electrical coupling between an antenna and a feeding circuit by mounting the feeding circuit to a rear face of the antenna via a conductive base, and connecting an output terminal of the feeding circuit and an antenna feeding point through the conductive base. CONSTITUTION:A ground conductor 11 is placed on one side of a base 1 and an antenna 10 is fitted by a screw Sa. Throughholes 3, 5 are formed to the base 1 corresponding respectively to both feeding points 13f1, 13f2 of a medium diameter disk conductor 13 of the antenna 10 and a feeding point 15f of a small diameter disk conductor 15. A hybrid circuit 30A is placed on the other face of the conductive base 1 with a screw Sb while its ground conductor 32 faces with the base 1. Thus, the ground conductor 11 of the antenna 10 and the ground conductor 32 of the hybrid circuit 30A are surely connected through the conductive base 1 inbetween and an outer conductor 24 of a coaxial feeder 22C and they are also connected surely to the ground conductor 32 of the hybrid circuit 30A similarly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an antenna power feeding device suitable for a back feeding type.

[Summary of the invention]

The present invention provides a method of connecting the antenna and the feeding circuit by attaching a feeding circuit to the back of the antenna via a conductive substrate, and connecting the output terminal of the feeding circuit and the feeding point of the antenna through the conductive substrate. This allows for easy and reliable mechanical and electrical connection.

[Conventional technology]

Conventionally, wireless communication systems between a base station and a large number of mobile stations have been constructed or proposed via geostationary satellites.

Such a wireless communication system, for example, as shown in FIG.
Downlinks are configured from the base station C3 to a large number of mobile stations M via the satellite STd, and from each mobile station to the base station C
The uplink to 8 is configured via the satellite STu. The frequencies used for uplink and downlink are, for example, 1.
6GHz and 4.2GHz. For example, a user HQ, such as a transportation company, and base station C3 are connected via separate communication lines.

In the above-mentioned wireless communication system, the antenna on the mobile station side has a simple configuration, a small size and a low profile, and can adapt to the elevation angle of a geostationary satellite in transmitting and receiving frequency bands that are far apart from each other. A material that satisfies various conditions such as having a desired directivity is suitable.

[Problem to be solved by the invention]

The present applicant has filed Japanese Patent Application No. 1983 (December 1988) as a device that satisfies the conditions of directivity, shape, and structure as described above.
(Application filed on May 29, 2013), a plurality of disc conductors are stacked on a ground conductor in order of increasing diameter through dielectric layers, and power is supplied to the center of the disc conductor with the smallest diameter.
By supplying offset power to the other disc conductors, the disc conductor with the smallest diameter becomes the radiating element for the highest frequency band, and the other disc conductors become ground conductors for the adjacent small diameter disc conductors, and gradually become lower. It also serves as a radiating element for the frequency band,
We have already proposed a back-fed microstrip antenna whose main radiation beam covers the required elevation angle range in the vertical plane in multiple frequency bands and is omnidirectional in the horizontal plane.

First, the previously proposed microstrip antenna will be explained with reference to FIGS. 4 and 5.

In FIGS. 4 and 5, (10) is a previously proposed microstrip antenna, in which a dielectric layer (12) of low member loss such as fluororesin is formed on a circular ground conductor (11). ) A medium-diameter disc conductor (13) is concentrically stacked, and a small-diameter disc conductor ( 15) are concentrically stacked and arranged. Each conductor (11).

radius of (13), (15), dielectric layer (12),
The dielectric constant and thickness of (14) are set as follows, for example.

r + r = 90mm, r + z = 55m
mr +5=26.5mm, e,=2.61.
2 = 1st = 3.2mm The medium diameter disc conductor (13) has r,
The feed points (13
f, ) and (13f,) are provided, and a small diameter disc conductor (
A power feeding point (15) is provided at the center of the power supply point (15). Feeding point (
The offset distance and angular interval of 13f, ) and (13f z) are set as follows, for example.

r t = 33 mm, θ = 135° Refeed points (13fl) and (13f, ) of medium diameter disc conductor (13)
Coaxial feed lines (21) and (22) are connected to these, respectively. In this case, the outer conductors of the refeed lines (21) and (22) are connected to the ground conductor (11).

Further, the inner conductor (26) of the coaxial feed line (25) is connected to the feed point (15f) of the small diameter disc conductor (15), and the outer conductor (27) of the feed line (25) is connected to the ground conductor (11). connected to.

Note that the medium-diameter disc conductor (13) is electrically connected to the ground conductor (11) by through-hole processing at its center, so that the outer conductor (13) of the coaxial feeder (25)
27) will be connected to the center of the medium diameter disc conductor (13).

The operation of the existing example is as follows.

The small diameter disc conductor (15) is centrally fed, and its radius is r
+5=26.5mm, 4 in TM mode
, 2 GHz, and becomes a vertically polarized radiating element.

At this time, the medium diameter disc conductor (13) is replaced by the small diameter disc conductor (15).
), providing a nearly conical vertical directivity with the main beam having the desired elevation angle range.

On the other hand, the medium diameter circle (anti-conductor (13) has an impedance of 50Ω each, the first feeding point (13f,) is at the reference phase (0°), and the second feeding point (-13f2) is at the -90° phase. It is excited in the TM2. mode by a 1.6 GHz signal, and becomes a circularly polarized wave radiating element, resulting in the desired vertical directivity in the shape of a cone.

In addition, since the impedance at the center of the radiating element is basically 0Ω in modes other than TMo, it operates by connecting the center of the medium-diameter disc conductor (13) to the ground conductor (11) as described above. stability will be achieved.

By the way, in the previously proposed example mentioned above, the medium diameter disc conductor (13)
The feeding points (13f, ) and (13fz) were designed to supply high frequency signals with a predetermined phase difference through coaxial feeding lines (21) and (22), respectively, but strip lines as shown in FIG. By using a phase difference feeding circuit (hybrid circuit) (30), the entire antenna system can be configured even more compactly.

That is, in FIG. 6, one copper foil (33) of a double-sided body-bonded laminate using a fluororesin layer (31) having a thickness of 0.8 mm, for example, is formed as shown. (34,) and (
34□) is an output terminal, and the above-mentioned antenna (10)
correspond to a pair of feeding points (13f, ) and (13f2), respectively. When a signal is supplied from the input terminal (35),
The left side from point A is symmetrical both vertically and horizontally. BC and BD
is set to approximately 1/4 of the effective wavelength, and the signal power at point A is equally divided and supplied to the re-output terminal (34,) and (34□), and the phase of the output terminal (34,) is is delayed by 90°. (36) is a terminal resistance terminal. Re-output terminal (3
41) and (34□) as shown in Figure 4.
f, ) and (13f2), this hybrid circuit (30) can be connected to the ground conductor (11
), and the corresponding output terminals and feed points can be easily connected with linear conductors (pins) (not shown).

When bonding the hybrid circuit (30) as described above to the back surface of the antenna (10) as described above, the other copper foil of the hybrid circuit (30) must be bonded to ensure mechanical and electrical connection between the two. (ground conductor) to the antenna (10)
It is common to solder the wire to the ground conductor (11) of the wire.

However, in this case, since the parts to be soldered are not exposed, the hybrid circuit (30) cannot be soldered using the normal method.
There was a problem in that only the peripheral edge of the solder could be soldered, making the work difficult.

By using a low melting point solder and performing a reflow process, it is possible to solder the entire surface of a relatively large area joint, but it takes a considerable amount of time and the antenna (10
) and the hybrid circuit (30) are difficult to control.

On the other hand, in Japanese Patent Application Laid-Open No. 63-33903 (Japanese Patent Application No. 61-178179), the present applicant attached an antenna and a coaxial connector for power feeding to both sides of an independent ground conductor, and attached and detached the antenna and the coaxial connector via a coupling member. We are proposing an ``antenna power feeding mechanism'' that can be connected to. This power feeding mechanism does not require soldering between the ground conductor of the antenna and the flange of the connector, improving workability. However, this mechanism cannot be applied to solve the above-mentioned problems.

In view of the above, an object of the present invention is to provide a feeding system for an antenna that can easily and reliably connect the antenna and the feeding circuit mechanically and electrically without requiring soldering of joints having a relatively large area. It is located where the equipment is provided.

(Means for Solving the Problems) The present invention provides a back-feed type antenna (10) that is attached to the negative side of a conductive substrate (1), and a strip-line type feed circuit ( 30) Attach
The output terminal of this feeder circuit (the feeding point of the antenna)
13b) is connected to the antenna by penetrating the conductive substrate.

[Effect]

According to this configuration, the antenna and the feeding circuit are easily and reliably coupled both mechanically and electrically.

〔Example〕

Hereinafter, an embodiment of an antenna power feeding device according to the present invention will be described with reference to FIGS. 1 and 2.

The configuration of an embodiment of the present invention is shown in FIGS. 1 and 2. In both figures, parts corresponding to those in FIGS. 4 to 6 are given the same reference numerals and redundant explanations will be omitted. do.

In FIGS. 1 and 2, (1) is a conductive substrate, for example, an aluminum material with a thickness of 3 nn+ is used, and a plurality of screw holes (2) are bored in the periphery of the substrate. The antenna (10) is attached with a screw Sa with the ground conductor (11) facing the negative side of (1).

Refeed point (
13f, ) and (13fz) and small diameter disc conductor (15)
The board (1) corresponds to the feeding point (15f) of
Through-holes (3) and (5) are bored in the holes (3) and (5).

On the other side of the conductive substrate (1), a hybrid circuit (30
A) is attached by screws sb with its ground conductor (32) facing the substrate (1). One output terminal (34□) of the hybrid circuit (30A) and one feed point (13f2) of the medium diameter disc conductor (13) are connected to the board (1).
They are connected to each other by soldering to both ends of pins (4) passing through the through holes (3). Although not shown, the other feed point (13f,) and output terminal (34+) are also connected in the same way. The inner conductor (23) of the semi-rigid coaxial feed line (22C) is soldered to the input terminal (35) of the hybrid circuit (308). This coaxial feed line (
22C) is attached to the board (
1).

Note that the feed point (15f) of the small-diameter disc conductor (15) is also connected to the strip line matching circuit by a via (6) that passes through the through hole (5) of the board (1), but for simplicity However, illustration thereof is omitted.

As configured as described above, in this embodiment, the ground conductor (11) of the antenna (10) and the ground conductor (32) of the hybrid circuit (30A) are connected to the conductive substrate (1).
), and the coaxial feed line (22
C) outer conductor (24) and hybrid circuit (30A)
It is also securely connected to the ground conductor (32).

Since both the horizontal ground conductors (11) and (32) are connected by the screws Sa and sb and the substrate (1), it is extremely easy and the workability is improved.

In the above embodiment, both the antenna (1o) and the hybrid circuit (30A) are connected to the ground conductors (11) and (32).
), but it is also possible to omit these ground conductors (11) and (32), as disclosed in the aforementioned Japanese Patent Application Laid-Open No. 63-33903.

In addition, the hybrid circuit (30A) of the conductive substrate (1)
This hybrid circuit (3
It is possible to reduce the weight by appropriately cutting off the thickness except for the part facing the 0A) and the vicinity of the perforated hole (2) on the periphery. When the antenna (10) is provided with a ground conductor (11), the surface of the substrate (1) on the antenna (10) side also connects with the through holes (3) and (5) in the opposing area of the hybrid circuit (30A). 1; The meat can be shaved in the same manner except for the vicinity of the Sb screw hole (not shown).

In addition, in the above-mentioned example, the hybrid circuit (30A)
Although a non-shielded strip line type is used, a shielded strip line type may also be used.

[Effects of the Invention] As detailed above, according to the present invention, a feeding circuit is attached to the back surface of the antenna via a conductive substrate, and the output terminal of the feeding circuit and the feeding point of the antenna are connected to each other through a conductive substrate. Since the connection is made through the substrate, it is possible to obtain an antenna power feeding device in which the antenna and the power feeding circuit can be mechanically and electrically coupled easily and reliably.

(15f) is the feed point, (22C) is the coaxial feed line, (30
), (304) is a phase difference feeding circuit, (34□),
(34□) is an output terminal, and (35) is an input terminal.

[Brief explanation of the drawing]

1 and 2 are a sectional view and a plan view showing the structure of an embodiment of an antenna power supply device according to the present invention, FIG. 3 is a conceptual diagram for explaining the present invention, and FIGS. 4 and 5. 6 is a plan view and a sectional view showing an example of the configuration of a back-feeding type antenna according to an existing proposal, and FIG. 6 is a plan view showing an example of the configuration of a feeding circuit for explaining the present invention. (10) is a back-feeding microstrip antenna,
(11), (32) are ground conductors, (12), (14
), (31) are dielectric layers, (13), (15)
is a disk conductor, (13r+), (tJz).

Claims (1)

[Claims] A back-feeding type antenna is attached to one side of a conductive substrate, and a strip line type feeding circuit is attached to the other side of the conductive substrate, and the output terminal of this feeding circuit and the feeding point of the antenna are connected to each other. A power feeding device for an antenna, characterized in that: and are connected to each other through the conductive substrate.