JPH03136404A - antenna device - Google Patents

Abstract

PURPOSE:To attain the operation of the antenna even during moving state at on-vehicle mount by arranging a planer antenna onto a conical base side face with a prescribed elevating angle. CONSTITUTION:A planer antenna 11 is arranged onto a conical base side face with a prescribed elevating angle. When a radio wave radiates to the antenna 11, an incident RF signal is frequency-converted into an IF signal by a frequency converter 12, a level detector 14 selects a large level of the IF signal and only an antenna directing in a direction close to an azimuth angle of an incoming radio wave. An output of the level detector 14 is fed to a control signal generator 15 and a switch circuit 16 is drive-controlled by the control signal and only selected four signals are connected to variable phase shifters 17-20. The phase shift of the phase shifters 17-20 is adjusted variably, outputs of the phase shifters are synthesized by a synthesizer 21 and then the azimuth angle is varied, then an optimum elevating angle is selected. Since the adjustment is implemented entirely electronically, the antenna. is operated even during moving at on-vehicle mount.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an antenna device for mobile communications, particularly mobile satellite communications or mobile satellite broadcast reception.

2. Description of the Related Art Conventional antenna devices include, for example, Japanese Patent Application Laid-open No. 61-80
It is shown in the 902 publication.

FIG. 6 shows a configuration diagram of the above-mentioned conventional antenna control for vehicle use, in which 70 is the primary radiator of the antenna, 71
72 is an offset reflector, 73 is a thickening/azimuth variable device, 74 is a controller for controlling the elevation/azimuth variable device 73, and a connecting line 75 is for controlling the elevation angle. A control signal is sent to the motor 79, a connection line 76 sends a signal to control the azimuth angle to the motor 79, and 77 and 78 are connection lines that send signals of the azimuth angle and the Nilevage-Zin angle to the controller.

In the conventional antenna device configured as described above, the controller controls the azimuth/elevation device f73 in a predetermined direction by picking up the outputs of a suitable horizontal sensor such as a gyro and a vertical sensor. In this case, the antenna control is performed when the vehicle equipped with the antenna is stopped, and is not controlled while the vehicle is moving.

Problems to be Solved by the Invention However, with the above configuration, due to the structure of the antenna, it is not possible to control the antenna while the car is moving, and since the antenna is controlled mechanically using a motor, the device may experience large vibrations. There was also the issue of requiring sufficient consideration of the credibility of such matters.

- In view of these points, the present invention enables reception by controlling the directivity of the antenna even when the car is moving, controls the directivity of the antenna electrically rather than mechanically, and has a height suitable for in-vehicle use. The purpose is to provide a compact antenna device with a low configuration.

Means for Solving the Problems The present invention provides a method for arranging several antennas in a circular manner (in this case, the antennas may be either integrated or divided), and arranged in a circular manner. It is electrically divided into N antennas (N is a positive integer) at equal intervals around the circumference, and each divided antenna has a received RF signal level or IF signal level detection function, and each RF signal level or IF signal level Equipped with a comparison judgment control signal generation function for determining the received signal level, the RF signal output or IF signal output of M antennas (M is a positive integer smaller than N) selected in order from the one with the highest received signal level is controlled by an electric switch. It is connected to M frequency converters, and a variable phase shifter is provided on the input side or output side of each frequency converter, and the outputs of each frequency converter or each variable phase shifter are combined into one to form an antenna. This is an antenna device characterized by controlling directivity.

Effect The present invention has the above-described configuration, and since the antenna is arranged at a constant elevation angle on the side surface of the truncated cone, the azimuth angle is 360 degrees.
When a radio wave arrives from one of the directions in the direction of the incoming radio wave, first, among the antenna blocks arranged separately, those antenna blocks that are close to the azimuth angle of the direction of the incoming radio wave catch the radio wave signal, even if only slightly. By detecting the level for each antenna, selecting the one with the highest signal level in order using a switch, and combining only the selected frequency converter outputs through a variable phase shifter, and controlling each phase shifter. Since the antenna elevation angle can be varied, it can be matched to the optimal elevation angle of the incoming radio waves.Also, all of this adjustment can be done electronically, so it can be operated even when mounted in a vehicle.Furthermore, the antenna can be adjusted by the angle of elevation. Since it is slanted, the height can be kept low, and it has a truncated conical shape, which has an advantageous effect on wind pressure.

Embodiment FIG. 1 shows a block diagram of an antenna device according to a first embodiment of the present invention. In Figure 1, 11
are planar antennas arranged in a truncated cone shape (antenna blocks A++, At□, Az□A) that receive incoming radio waves from the outside.
2□,...) 12 is a frequency converter that converts the frequency of radio waves received by the planar antenna 11, 13 is a frequency converter 1
This is a local oscillator that supplies a local signal to 2. Further, 14 is an input signal level detector, 15 is a switching control signal for selecting a high level frequency converter output from among the outputs of the input signal level detector 14, and a shift control signal for controlling the amount of phase shift of the variable phase shifter. A control signal generator that generates a phase control signal, 16 a switch circuit that performs switching according to a control signal from the control signal generator 15, 17.18.19゜20
1 is a variable phase shifter that varies the phase of each of the four signals selected by the switch circuit 16 according to a control signal from the control signal generator 15; 21 is a variable phase shifter 17° 1B;
9. A signal combiner which combines the outputs from 20, and 22 is a combined signal output. Note that in this embodiment, for the sake of explanation, four signals are used, but any number may be used.

The operation of the antenna device of this embodiment configured as described above will be described below. When a radio wave is incident on the planar antenna 11, this incident RF signal is frequency-converted by IF times by the frequency converter 12, and each of these! The F-fold signal output levels are detected and compared by a level detector 14, and the one with the higher level is selected. That is, only antennas facing in a direction close to the azimuth of the arriving radio wave are selected. This level detector output is applied to a control signal generator 15, and the control signal from the control signal generator 15 drives and controls a switch circuit 16 that passes only selected high-level signals, for example, four signals, and are connected to variable phase shifters 17, 18, 19, and 20, and each phase shifter changes the input signal to a phase angle of 81 degrees, 82 degrees, 8 degrees.
2 degrees, 84 degrees (for example, θ, = 0 degrees, θ2 = 90 degrees, θ'
s = 180 degrees, θ4 = 270 degrees) and output with different delay phase amounts. By varying and adjusting the phase amount of this phase shifter and composing the outputs of each phase shifter in the synthesizer 31, the elevation angle of the azimuth can be changed, so that the optimum elevation angle can be selected. FIG. 2 shows a schematic diagram of this embodiment. Figure (a) is a side view of the truncated conical antenna 10, and figure (c) is a plan view. As can be seen from both figures, the planar antenna block 11 is lined up on the side and covers 360 degrees in the horizontal direction. There is.

As shown in FIG. 4A, level detection may be performed not from the outputs of all the antenna blocks 11, but from either the upper or lower sides of the sides. In the same figure (C), it is divided into two in the height direction, but generally it can be divided into two (K is a positive integer). When the elevation angle θ is set at a part of the truncated conical antenna 10, the elevation angle can be varied by ±φ around the elevation angle θ by phase shift synthesis of the antenna outputs. For example, in Japanese satellite broadcasting, most areas can be covered if the elevation angle can be varied from 30° to 60', so it is sufficient to set θ = 45'' and φ = ±15@.In other words, the direction of the antenna's directivity The angle and elevation angle can be automatically set to the optimal direction. Figure 3 shows a specific configuration diagram of the truncated conical planar antenna.
a) is a cross-sectional view of a planar antenna, 23 is a patch antenna part with a slot, 24 is a feed line part, 25 is a ground conductor part, 26 is an insulator part of a dielectric layer made of a low permittivity, low loss material. If .24 is made by providing a conductive foil on a plastic film carrier, it will be flexible against bending and a curved surface can be easily formed. 12 is a frequency converter attached to each antenna block 11. Same figure (b)
, (C) is an example of a pattern development diagram of 23 and 24 shown in FIG.

As described above, according to this embodiment, since the antenna is arranged in the shape of a truncated cone, the azimuth angle in any direction of 360 degrees can be covered, and the elevation angle can also be controlled at the same time by providing a phase shift control function. Therefore, the directivity of the antenna can be automatically adjusted only by electrical control without any mechanical rotation function, making it very effective for vehicle-mounted antennas and the like.

FIG. 4 shows diagrams of an antenna device according to a second embodiment of the present invention, where (a) is a side view, (b) is a plan view, and (c) is a cross-sectional view. . 29 in Figure 4
is an inverted truncated conical antenna provided inside the truncated conical antenna 10, and the side inclination is symmetrical to that of the truncated conical antenna 10. Each antenna block 30 (small block BI I +B+z, B□) of the inverted truncated conical antenna shown in FIG.
, Bit), and the antenna block 11 (small blocks Az, Adz, Az++A) in the shape of a truncated cone.
z t ) corresponding antenna small blocks A 11 and B I I + A I ! and Lx, Al
l and Ba1l Azz and BztC generally A, 7 and B-:
(m, n are positive integers) is the directional characteristic 31. shown in FIG.
As can be seen from 32 or 33.34, they are configured to face almost the same azimuth angle and the same elevation angle. In addition, in the antenna device of this embodiment configured as 0 or more in which the outputs of the frequency converters of the corresponding antenna small blocks are combined and extracted, the corresponding antenna small blocks A,
and B I l + Al 1 and ILz, All and B! I'b AZR and B2□ (generally A1., and B,,
) are configured to face almost the same azimuth angle and the same elevation angle, and the outputs of the frequency converters of each corresponding antenna small block are combined and extracted, so the size of the received radio wave is as shown in Figure 1. Approximately twice the level can be obtained as in the embodiment, and the area occupied by the antenna remains unchanged.

FIG. 5 is a diagram showing an antenna device according to a third embodiment of the present invention. In the figure, (a) is a sectional view, and (a) is a plan view seen from the back side of the planar antenna. In the figure, 37 and 38 are small antenna block parts of a phased array antenna, 39 are patch antenna pattern parts patterned with conductive foil on a metal plate or plastic film, and 40 and 41 are low-loss, low-permittivity plastics. This is a feed line pattern portion formed into a pattern on a film carrier 42 made of a film or the like. 43 is a dielectric layer (or air layer) with low loss and low dielectric constant to reduce the loss of the power supply line. 45 is a grounding conductor 44 and a grounding conductor 46
The same local signal is supplied to each frequency converter 48.49 from a local signal supply terminal 52.53 using the center conductor of a triplate strip line composed of a dielectric material 47 and a dielectric material 47. In addition, each reception R from the small antenna block 37.38
The F signal is supplied to the frequency converter 48.49 from the RF signal output terminal 50.51, frequency-mixed with the local signal from 52.53, frequency-converted to the IF frequency, and sent to the ground conductor 46. Dielectric 54. It is taken out from a microstrip line 55.56 formed by a center conductor 55.56. 5
The IF multiplied signal from 5.56 is applied to a signal synthesizer 59 via variable phase shifters 57 and 58, and its output is taken out from 60.

As described above, according to this embodiment, by providing a triplate strip line on the ground plane side of the planar antenna, it is possible to supply the common local signal required for the frequency converter of the phased array antenna with a planar circuit. It can be realized with a very simple configuration that is compatible with planar antennas compared to coaxial lines etc. Further, since a triplate strip line with low loss and little radiation is used, the total power of the supplied local signal can be reduced, and leakage of the local signal to the outside can be sufficiently suppressed. In addition, the frequency converter is an MIC circuit (MIC circuit) using a microstrip line.
rowave Integrated C1rcuit
), the antenna, local supply line, and frequency converter can all be made into planar circuits, making it possible to construct a very compact phased array antenna as a whole.

In addition, in the first to fourth embodiments, a multilayer structure type planar antenna was shown as an example of the planar antenna, but
Needless to say, any other planar antenna such as a microstrip array antenna may be used.

As described in detail, according to the present invention, the planar antenna is arranged on the side surface of a truncated cone at a constant elevation angle, so even when radio waves arrive from any direction within a 360-degree azimuth, the antenna can be automatically activated. Since the azimuth angle can be selected and the antenna elevation angle can be varied, the azimuth angle and elevation angle of the antenna can be matched to the optimal direction of the incoming radio waves. Furthermore, all of this adjustment can be done electronically, so it can be operated even when the device is mounted on a vehicle. Furthermore, since the antenna is tilted by the angle of elevation, the height can be kept low, and since it is shaped like a truncated cone, it has an advantageous effect on wind pressure. Furthermore, if an inverted truncated conical antenna is provided inside the truncated conical antenna, it is possible to configure two antennas within the same small area, increasing the overall antenna gain and creating an antenna with higher sensitivity. This makes it extremely effective as an antenna for mobile objects. In addition, by providing a triplate strip line on the ground plane of the phased array antenna, it is possible to supply a common local signal to each frequency converter with a simple configuration, suppress local signal radiation, and with low loss, and other practical effects. is big.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an antenna device according to a first embodiment of the present invention, FIG. 2 is a schematic diagram of the same embodiment, FIG. 3 is a specific configuration diagram of the same embodiment, and FIG. FIG. 5 is a configuration diagram of an antenna device according to a second embodiment, FIG. 5 is a configuration diagram of an embodiment in which a local signal supply line is integrated with the antenna device of the present invention, and FIG. 6 is a configuration diagram of a conventional antenna device. 10... truncated conical antenna, 11...
Planar antenna, 12... Frequency converter, 13.
... Local oscillator, 14 ... Input signal level detector, 15 ... Control signal generator, 16
・・・・・・Switch circuit, 17.18.19.20・
... variable phase shifter, 21 ... signal synthesizer,
22... Combined signal output, 23... Patch type planar antenna section, 24... Feeding line section, 25
...Grounding conductor part, 26...Insulator part,
27...Slot pattern, 28...
'A pattern for power feeding, 29... Inverted truncated conical antenna, 30... Antenna block, 37.38
...Small antenna block part of phased array antenna, 39...Patch antenna pattern part, 40.41...Feed line pattern, 42...
...Film carrier, 43...Dielectric layer,
45...Tri-plate type strip line, 4
8.49...Frequency converter, 52, 53...
...Local signal supply terminal, 55.56...
Microstrip line, 57.58...variable phase shifter.

Claims (8)

[Claims] (1) A planar antenna is arranged on the side surface of a truncated cone or an inverted truncated cone with a constant elevation angle, and the antennas are separated and arranged circumferentially in N equally spaced rows (N is a positive integer). and K antennas (K is a positive integer) are arranged separately in the height direction, and each of the separated antennas is provided with a frequency converter, and the magnitude of each output IF signal level or S/N level of each frequency converter is provided. and a comparison/determination function for determining each level.
is a positive integer smaller than N) and the IF signal outputs from the K antenna blocks on each column are connected to M·N IF band variable phase shifters by electrical switches, and each variable phase shifter is An antenna device characterized in that the outputs of the antennas are combined into one to control the directivity of the antenna. (2) A planar antenna is arranged on the side surface of a truncated cone or an inverted truncated cone with a constant elevation angle, and the antennas are separated and arranged circumferentially in N equally spaced rows (N is a positive integer). The antennas are separated into K antennas (K is a positive integer) in the height direction, and each separated antenna is equipped with a received RF signal level detection function.
It is equipped with a comparison judgment function that determines the magnitude of each RF signal level, and selects the one with the highest received signal level from among the N antennas arranged around the base of the truncated cone or on the upper base of the inverted truncated cone. M items selected in order (M is a positive integer smaller than N)
M·K RF signal outputs from each output of the K antenna blocks on each column are combined through RF band variable phase shifters, and then added to a frequency converter, or
・The directivity of the antenna is determined by connecting the K RF signal outputs to the M·K frequency converters using electrical switches, and combining the output IF signals through IF band variable phase shifters. An antenna device characterized by controlling. (3) The antenna device according to claim (1) or (2), wherein the gains of all antenna blocks are made substantially the same. (4) A first antenna is arranged in a side wall shape of a truncated cone, and a second antenna is arranged in a side wall shape of an inverted truncated cone within the side wall surface.
An antenna device characterized in that a plurality of inverted truncated conical antennas and a plurality of truncated conical antennas are alternately arranged within a side wall surface of the first antenna. (5) A first antenna is arranged in a side wall shape of a truncated cone, and a second antenna is arranged in a side wall shape of an inverted truncated cone within the side wall surface.
The antenna device according to any one of claims 1 to 4, characterized in that said antennas are arranged side by side, and said first antenna and said second antenna receive and combine the same signals. (6) A first antenna is arranged in a side wall shape of a truncated cone, and a second antenna is arranged in a side wall shape of an inverted truncated cone within the side wall surface.
The antenna device according to any one of claims 1 to 4, characterized in that two antennas are arranged side by side, and the first antenna and the second antenna receive different signals. (7) A first antenna is arranged in a side wall shape of a truncated cone, and a second antenna is arranged in a side wall shape of an inverted truncated cone within the side wall surface.
antennas are arranged, the first antenna and the second antenna receive different signals, and the IF frequency of the frequency converter of each of the first antenna and the second antenna is the same frequency. Claim (1) characterized in that the variable phase shifter is shared by switching the output of the frequency converter.
The antenna device according to any one of (4) to (4). (8) A triplate strip line is attached to the ground conductor of the phased array antenna, and a common local signal is supplied from the triplate strip line to each frequency converter connected to each antenna block of the phased array antenna. An antenna device characterized by: