JPH0865031A - Directivity adjustment device for optical communication antenna - Google Patents

Abstract

PURPOSE: To eliminate the fine adjustment of the direction of an antenna at the time of installation and to stably transmit and receive signals by switching the connection of respective elements to a load on a side provided with plural light emitting elements or light receiving elements. CONSTITUTION: A condensing lens (convex lens) is used for a light receiving antenna 36 and the light receiving elements 34-1, 34-2, 34-n are arranged near the focus. In this case, they are arranged approximately linearly in both end directions of the convex lens against the focus. The arrangement may be staggered arrangement. Then, light sent out from the transmission antenna of another station opposite to an optical communication equipment 30 is converged by the condensing lens and reaches the light receiving elements 34-1, 34-2,-34-n. By the appropriate arrangement of the light receiving elements 34, the signals of different amplitudes are outputted to the respective elements. A signal level is detected in a signal level meter 32-2, the light receiving element 34 capable of obtaining the maximum amplitude is selected and a changeover switch 32-1 is controlled. As the result, the output signals of the large amplitude are inputted to the optical communication equipment 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for adjusting the directivity of an antenna in an optical communication device using infrared rays.

[0002]

2. Description of the Related Art Conventionally, a wireless LAN using infrared rays or controlling movement of a robot by infrared rays is an example of practical application of an optical communication device.

Generally, in a communication device using optical communication, for example, infrared rays, the configuration shown in FIG. 3 is known. FIG.
In, infrared communication devices 10 and 20 face each other and are installed on walls or ceilings 14 and 24, respectively. The infrared communication devices 10 and 20 are respectively provided with antennas 11 and 21, and each antenna 11 and 21 has a transmitter (light emitting element) 1
2 and 22 and light receiving portions (light receiving elements) 13 and 23.

A "lens" (not shown) is provided in each of the transmitters 12 and 22, and the light emitted from the light emitting element is directed to the light receiving portions (light receiving elements) 13 and 23 of the light receiving device facing each other, and is transmitted in a concentrated manner. At this time, the light is modulated by light intensity modulation or the like. The light receiving sections (light receiving elements) 13 and 23 are processed after being collected by a “lens” (not shown).

An example of controlling a moving body such as a robot by infrared rays is disclosed in Japanese Patent Laid-Open No. 62-2769.
No. 32 publication. When a moving object such as a robot suddenly loses control of infrared rays due to a step on the floor, etc., and becomes uncontrollable, the optical system is automatically controlled to expand the angle of light transmission and reception, for example, a zoom lens. It is described to be used and controlled.

[0006]

In the device shown in FIG. 3,
Since the directivity of infrared rays is strong, when installing the equipment at the beginning,
Especially the adjustment of the antenna system became complicated and troublesome. That is, the arrival distance of the infrared rays must be within several tens of meters and within the line-of-sight distance, and it was necessary to repeat the adjustment while finely adjusting the inclination of the lens and the like so that the infrared rays surely reach the opposing device. .

Further, in the case of a mobile robot, the light emitting unit and / or
Since the light receiving part is automatically adjusted so as to widen the transmitting / receiving angle of the infrared device, both the detecting element and the corresponding operating device are complicated and expensive. In order to widen the light transmission / reception angle and reach the opposite partner, it is necessary to increase the output of the light emitting element, and in order to widen the light reception angle, a troublesome process such as exchanging the light receiving lens is required.

The object of the present invention is to remedy the above-mentioned drawbacks and to end the adjustment by a relatively simple means at the beginning of the installation of the communication device, after which the directivity of the antenna is checked and the necessary adjustment is made at a predetermined time. Another object of the present invention is to provide a directivity adjusting device for an optical antenna.

[0009]

FIG. 1 is a diagram showing the principle configuration of the present invention. In FIG. 1, an optical communication device 30 shows a signal processing portion as a whole, and an antenna and a light emitting element / light receiving element for optical communication are separately shown. The light emitting elements 33-1, 33-2, ... And the light receiving elements 34-1,34-2 ,. Switching unit 31, 3
Reference numeral 2 is used to selectively connect a predetermined element from each of the light emitting element and the light receiving element. The transmitting antenna 35 and the light receiving antenna 36 transmit or receive an optical signal.

In an antenna of an optical communication device using a light beam as a signal transmission path, a plurality of one or both of a light emitting element and a light receiving element and a plurality of the light emitting element or the light receiving element are provided on each side. And a switching unit for switching the connection to the load.

[0011]

When the communication device 30 using light is made to face each other,
The antenna parts 35 and 36 are installed at positions where the antenna of the other communication device can be seen through. Then, the transmitting and receiving corner antennas are made to face each other, and the direction of the antenna is finely adjusted until it is possible to confirm that the transmitted light enters the antenna of the partner device by appropriate means. The adjustments required in the present invention are sufficient up to this point. Next, for example, by adjusting the switching unit 32, the light receiving elements 34-1,
The adjustment is completed by switching connection with any one of 4-2 to 34-n and connecting with the element that obtains the best reception result. The same may be done for the transmitting antenna. Thus, the directivity of the antenna can be set in a good state by almost only electrical processing.

[0012] After adjustment, there is a lapse of time for a while,
The switching units 31 and 32 are moved to the adjacent points for viewing. Then, when the result of the changed signal is better than that of the conventional connection point, the connection is changed.

[0013]

FIG. 2 is a diagram showing the configuration of an embodiment of the present invention. In FIG. 2, the light receiving antenna 36 uses a condenser lens (convex lens), and the light receiving elements 34-1, 34-2, ...
34-n are placed. In FIG. 2, the convex lenses are arranged in a substantially straight line toward both ends of the lens. This arrangement may be a staggered arrangement. The changeover unit 32 includes a changeover switch.
32-1 and signal level meter 32-2 are included. The signal selected by the changeover switch 32-1 is applied to the optical communication device 30.

In the operation of FIG. 2, the light transmitted from the transmitting antenna of the other station facing the optical communication device 30 is focused by the condenser lens 36.
The light is collected by and reaches the light receiving elements 34-1, ... 34-n. By appropriately disposing the light receiving element 34, signals with different amplitudes are output to the corner elements. The signal level meter 32-2 detects the signal level, selects the light receiving element 34 that provides the maximum amplitude, and controls the changeover switch 32-1. As a result, a large amplitude output signal can be input to the optical communication device.

Although the light receiving antenna 36 in FIG. 2 is shown as a condenser lens, it is possible to use a concave mirror and dispose the light receiving element in the vicinity of its focal point. In that case, the operation of the light receiving element is similar to that of the convex lens. A parabolic antenna may be used instead of the concave mirror.

Although the switching output of the switching unit 32 is shown as a single case, it is also possible to combine the outputs of the light receiving elements by an OR circuit to form an output. In the case of a single signal, it is possible to selectively output a signal with less noise, so there are not many cases where a combined output is used.

[0017]

As described above, according to the present invention, there is almost no need to finely adjust the direction of the antenna when the apparatus is installed, and stable signal transmission / reception becomes possible. Then, when time elapses, the connection is changed to the adjacent element and the change in the amplitude is checked, and if it is necessary to change the connection with the best element, the connection is changed so that good optical communication is always performed. It is possible. Note that the processing can be easily executed automatically.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention.

FIG. 2 is a diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a conventional technique.

[Explanation of symbols]

 30 optical communication device 31, 32 switching unit 33-1, 33-2, ~, 33-n light emitting element 34-1, 34-2, ~, 34-n light receiving element 35 sending antenna 36 light receiving antenna

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical indication H04B 10/22

Claims (1)

[Claims] 1. An antenna of an optical communication device that uses a light beam as a signal transmission path, wherein one or both of a light emitting element and a light receiving element are provided in plural, and a side provided with a plurality of the light emitting element or light receiving element, A directivity adjusting device for an optical communication antenna, comprising: a switching unit that switches a connection of each element to a load.