JPH0470201A - Scan antenna - Google Patents

Abstract

PURPOSE:To simplify a rotary mechanism, to simplify the connection of a radiating element with an external part and to set a system to be with stand considerable shift or vibration by rotating only a reflecting mirror. CONSTITUTION:The rotation of a motor 16 is transmitted to the inner gear 14 of a rotor 13 through a gear 17 fixed to a motor shaft and the rotor 13 rotates. An electromagnetic wave generated in a radar circuit reaches the primary radiating element 7 in the focus of a paraboloid 1 through a transmission line 8, is radiated toward the paraboloid 1, is reflected and converged on the paraboloid 1 and is emitted toward the direction of the center line of the paraboloid 1 with maintaining sharp directivity. Since the paraboloid 1 forms a part of the rotor 13 and is continuously rotating, the electromagnetic wave reflected on the paraboloid 1 and emitted in scan space is in a direction where a conical surface at a vertical angle 2theta as against the rotary center line of the rotor 13, namely, the flight direction of a flying body is set to be a locus. The electromagnetic wave discharged in scan space reaches an investigating object and a reflected wave from the investigating object is reflected on the paraboloid 1, is converged on the primary radiating element 1 in the focus of the paraboloid 1 and is guided to a radar circuit through the transmission line 8.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a scanning antenna for target detection mounted on a flying object such as a missile shell.

(Prior Art) Conventionally, this type of device includes a radar antenna device (Japanese Utility Model Application Publication No. 59-61615) consisting of a fixed conical horn and a rotating reflector, and a fixed primary radiation An antenna device that moves a curved reflecting mirror along a predetermined trajectory in accordance with the system (Japanese Patent Laid-Open No. 61-74402);
A main reflecting mirror with a spherical shape and two auxiliary reflecting mirrors are installed.
A spherical mirror antenna that rotates this auxiliary reflector (Japanese Unexamined Patent Publication No. 5
2 = Publication No. 73655) was mxed.

(Problem to be Solved by the Invention) These proposals generally have a complicated structure and lack mechanical robustness, so they have the disadvantage that they are not suitable as antenna devices for flying objects.

The present invention aims to improve the above-mentioned drawbacks and provide a scanning antenna that operates with a simple drive mechanism, does not require a flexible transmission path, and yet can withstand extreme movements such as those of a flying object. purpose.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a reflecting mirror that matches the shape of a paraboloid, and a mirror that passes through the focal point of the paraboloid and the angle
A means for rotating the reflecting mirror about an axis having a fixed angle with the central axis of the paraboloid, a radiator provided at the focal point of the paraboloid, and a position where the rotating axis and the reflecting mirror intersect. The gist of the invention is a scanning antenna characterized in that the scanning antenna is provided with a transmission line connected to the radiator except for the hole provided in the reflecting mirror.

Furthermore, the present invention has an outer shell comprising a dome made of a radio wave transmitting material, and a shaft portion provided inside the outer shell, extending in the axial direction of the dome, and having a hole in the center for accommodating a transmission path. a holder, a rotating part having a paraboloid formed on one end surface and rotated by a rotation means provided on the holder on the other end surface, a center line of the paraboloid, and the rotating body. is arranged at a predetermined angle with the rotation axis, is connected to a primary radiator placed at the focal point of the paraboloid, and is placed through a hole provided at the center of the rotation axis. The gist of the invention is a scanning antenna characterized by comprising a transmission path.

(Function) As described above, the present invention only rotates the reflecting mirror, so the rotating mechanism can be simplified, and the connection between the radiator and the outside is also simple, and it is possible to avoid extreme movement or It can also withstand vibrations.

(Example 1) Next, examples of the present invention will be described.

Figure 1 shows the scanning antenna of the present invention. In the figure, 1 is a paraboloid, 2 is the central axis when the paraboloid 1 is rotated, and 3 is the bottom of the paraboloid. provided in the part,
A reflecting mirror matching the shape of the paraboloid of revolution, 4 a hole formed in a part of this reflecting mirror, 6 the focal point of the paraboloid, 5 passing through this focal point, and aligning with the central axis 2 as desired. The rotation axis has an angle, and the hole 4 is provided at a position where the rotation axis 5 and the reflecting mirror 3 intersect. Reference numeral 7 denotes a primary radiator provided at the focal point of the paraboloid, and a transmission line 8 is connected to the radiator 7 with the hole 4 still mentioned above.

Next, the operation will be explained.

(a) The radiator 7 is placed at a pointless point 6 on the paraboloid of revolution 1, and the reflector 3 rotates about a rotation axis 5 having an arbitrary angle with the center ring 2 thereof.

(D) Therefore, even if the reflector 113 rotates, the positions of the focal point 6 and the radiator 7 always remain fixed.

(71) Therefore, the central axis 2 of the paraboloid of revolution makes a conical motion with the focal point 6 as a fixed point.

2' and 3' in the figure indicate the position of the center axis of the paraboloid of revolution and the position of the reflecting mirror when rotated by 180°, respectively.

In this case, the transmission line 8 and the radiator 7 are in a stationary state.

(Example 2) FIG. 3 shows a cross section of the tip of a flying object having a scanning antenna according to the present invention. 10 is the outer shell of the flying object, and a dome 11 made of a radio wave transparent material is fixed to the tip of the shell. Further, the rotation mechanism holder 12 is fixed inside the outer shell IQ, and the 0-rotation mechanism holder 12 has a convex central cross section.
A hole 4 is formed in the center thereof, through which a transmission line 8 to be described later passes. Reference numeral 13 denotes a rotating body having a paraboloid l at one end, the central axis 2 of the paraboloid 1 and the central axis 5 of the rotating body 13 have a predetermined inclination angle θ, and the focal point 6 of the paraboloid 1 is configured to exist on the rotating body 130 rotating wheel 5, and the rotating mechanism holder 1
An internal gear 14 is constructed on the other end side of the zero-rotating body 13 which is held in a rotatable state by the rotor 2. Further, a hole 4 through which the transmission Ws8 passes is bored in the center of rotation of the rotating body 13. A motor 16 is fixed to the rotating mechanism holder 12, and a gear 17 is fixed to the rotating shaft of the motor 16, and is engaged with the internal gear 14. One end of the transmission line 8 is connected to the primary radiator 7 located at the focal point of the paraboloid 1, and the other end is connected to a laser circuit (not shown) mounted in a part of the flying object through the hole in the rotating mechanism holder 12. They are connected through 4.

Next, the present invention will be explained in detail. The rotation of the motor 16 is caused by the internal gear 1 of the rotating body 13 via a gear 17 fixed to the motor shaft.
4, and the rotating body 13 rotates. Electromagnetic waves generated by a radar circuit (not shown) pass through a transmission path 8 to a paraboloid 1.
It reaches the primary radiator 7 at the focal point of , is emitted toward the paraboloid 1, is reflected by the paraboloid 1, converges, maintains a sharp interdigitation, and is emitted in the direction of the center line of the paraboloid L. be done. On the other hand, paraboloid l
forms part of the rotating body 13 and is constantly rotating, so the t magnetic wave reflected by the paraboloid 1 and emitted into the scanning space is
This is a direction in which the locus is a conical surface having an apex angle of 2θ with respect to the rotation center line of the rotating body 13, that is, the flight direction of the flying object.

The electromagnetic wave emitted into the scanning space reaches the object to be explored, and the reflected wave from the object is reflected by the paraboloid 1 and converged on the primary radiator 7 at the focal point of the paraboloid 1, which transmits the transmission line 8. Needless to say, the signal is guided to a radar circuit (not shown) via the radar circuit.

(Embodiment 3) FIG. 4 shows another embodiment of the present invention, and the differences from the previous embodiment will be described. In the previous embodiment, the rotating body 13 had a paraboloid L at one end and the internal gear 14 at the other end, but in this embodiment, the rotating body 13 had a paraboloid 1 at one end. An external gear 18 is configured in the other @mail.

Therefore, as the motor 16 rotates, the rotating body 13 rotates.

Furthermore, the operation is almost the same as that of the embodiment shown in FIG.

(Embodiment 4) A fourth embodiment of the present invention is shown below. Fig. 5 shows a cross section of the tip of a flying object that grows a scanning antenna according to the present invention. 10 is the outer shell of the flying object; A dome 11 made of a radio wave transparent material is fixed to the tip.

Further, a rotation mechanism holder 12 is fixed inside the outer shell 10. The zero-rotation mechanism holder 12 has a convex central section, and has a hole 4 in the center thereof through which a transmission line 8, which will be described later, passes. 13 is a rotating body having a paraboloid 1 at one end,
The center line 2 of the paraboloid 1 and the center line 5 of the rotating body 13 have a predetermined inclination angle θ, and the focal point of the paraboloid 1 is located on the center line of the rotating body 13, Rotating mechanism holder 1
2, it is held in a freely rotational state. 19 is a stator coupled to the rotating mechanism holder [2]. A rotor 20 is connected to the rotating body 13, and the stator 19 and rotor 20 constitute an outer rotor type motor 2.

The rotating body 13 is rotated by this motor (2).

Other operations are almost the same as in FIG. 3.

(Effects of the Invention) Since the present invention is formed as above, only the reflecting mirror is rotated, so that all the high frequency circuits, signal processing circuits, etc. can be fixed from the transmission path including the radiator.

This eliminates the need for flexible transmission lines,
The rotary socket is no longer needed.

Therefore, it is highly durable, eliminates the risk of noise generation, and has the effect of making it easier to design a structure that can withstand the acceleration of a flying object because the reflector is simply rotated in conjunction with the structure. .

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the scanning antenna of the present invention, FIG. 2 is an explanatory diagram of the operation, and FIGS. 3 to 5 show other embodiments of the present invention. 1... Paraboloid 2... Central axis 3... Reflection @ 4... Hole 5... Rotation axis 6... Focal point 7... Primary radiator 8... Transmission line 10 ...outer shell
11...Dome 12...Rotating mechanism holder 13...
・Rotating body 14...Internal gear 16...Motor 17...Gear 18...External gear 19・
...Stator 20...Rotor■...Motor Figure 3

Claims (2)

[Claims] (1) A reflecting mirror that matches the shape of a paraboloid, and the reflecting mirror is rotated about an axis that passes through the focal point of the paraboloid and has a constant angle with the central axis of the paraboloid. means, a radiator provided at the focal point of the paraboloid, and a transmission line connected to the radiator through a hole provided in the reflecting mirror at a position where the rotation axis and the reflecting mirror intersect. A scanning antenna featuring: (2) an outer shell comprising a dome made of a radio wave transparent material;
A holder is provided inside the outer shell, extends in the axial direction of the dome, and has a shaft portion provided with a hole in the center for accommodating a transmission path, and a paraboloid is formed on one end surface side, and the other end surface is formed with a paraboloid. On the end face side, a rotating part rotated by a rotating means provided on the holder, a center line of the paraboloid, and a rotation axis of the rotating body are arranged at a predetermined angle, and the paraboloid a transmission line connected to a primary radiator placed at a focal point of the rotating shaft and passing through a hole provided at the center of the rotation axis.