JP2003273809A - Apparatus and system for optical space communication - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, in a conventional optical space communication apparatus for one-to-multi points communication, if the number of actual destination devices is less than the number of pieces of movable mirrors, lights applied to the movable mirrors which are not in use become wasteful. <P>SOLUTION: An optical space communication apparatus performing information communication among a plurality of destination devices 11a-11d, located at different places respectively by using optical signals propagated in the air comprises an optical source 101 for emitting the optical signals, a movable mirror array 104 in which a plurality of mirrors for reflecting optical signals from an optical source 101 are placed in a matrix form and directions of each mirror can be changed individually, and a mirror control means 105 for controlling the directions of the each mirror to form a plurality of mirror groups for reflecting respectively the optical signals toward different destination devices in the mirror array 104, so that the number of mirrors which are formed in the mirror array 104 can be changed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical space communication device for simultaneously communicating from one point to a plurality of points such as remote areas by an optical signal propagating in the air.

[0002]

2. Description of the Related Art Conventionally, using an optical signal propagating in the air,
In an optical space communication device for so-called point-to-multipoint communication, which simultaneously communicates from one point to a plurality of points such as remote places, a predetermined number of movable mirrors are installed in a light flux of light emitted from one light source, It has been proposed that the movable mirrors have different directions to achieve communication with the plurality of points.

Here, FIG. 7 shows an example of the apparatus having the above configuration. In FIG. 7, reference numeral 70 denotes an optical space communication device installed on one side of a point-to-multipoint communication, 71a, 71b, 71c.
Indicates a partner device on the multipoint side installed at a plurality of points in a remote place.

The optical signal emitted from the light source 701 is transformed by the optical system 702 into a slightly divergent substantially parallel light beam 703. This light beam 703 is composed of three movable mirrors 704a, 7a installed in the light beam.
04b and 704c, respectively, partner device 71a, 7
Separately reflected in a certain direction of 1b and 71c. As a result, a signal is sent to each partner device.

Each movable mirror 704a, 704b, 704
c is configured so that the orientation can be set freely,
When the device is installed, the orientation is set so that the light beam can be transmitted to each partner device.

As a result, it is possible to realize an optical space communication device for point-to-multipoint communication, which is capable of communicating with a plurality of partner devices with a light beam emitted from one light source 701.

[0007]

However, in the above-mentioned conventional example, the number of movable mirrors in the optical space communication device is determined at the manufacturing stage of the device, but in the environment where the device is actually used, the communication partner Does not always match the number of movable mirrors in the device. Rather, it is thought that there are more cases of disagreement.

Further, when the number of actual counterpart devices is smaller than the number of movable mirrors provided in the device, the movable mirrors are not used by the number corresponding to the difference, but even for the movable mirrors not used. Since the light always shines on the light source, the light shining on the movable mirror that is not used is wasted. That is, for example, when a device having four movable mirrors is used for communication with a partner device installed at two places, only 1/2 of the power of the light source is effectively used.

On the other hand, when the number of the counterpart devices is larger than the number of the movable mirrors provided inside the device by, for example, one, it goes without saying that another device needs to be installed. There is a problem that the device used for point-to-point communication lacks flexibility and the inherent performance of the device cannot be effectively used.

Therefore, it is an object of the present invention to provide a flexible optical space communication device capable of maximally effectively utilizing the inherent performance of the device regardless of the number of partner devices in one-to-many point communication. I am trying.

[0011]

In order to achieve the above-mentioned object, in the first invention of the present application, an optical signal propagating in the air is used to communicate information with a plurality of partner devices installed in different places. In an optical space communication device that performs communication, a light source that emits an optical signal and a plurality of mirrors that can reflect the optical signal from the light source are arranged in a matrix, and the movable mirrors can change the direction of each mirror independently of each other. An array,
A mirror group formed in the movable mirror array is provided with mirror control means for controlling the directions of the respective mirrors so that a plurality of mirror groups for reflecting optical signals are formed in different directions in the movable mirror array. The number of can be changed.

As a result, it is possible to freely set the number of mirror groups that reflect optical signals to different partner devices in accordance with the number of partner devices, and to transmit a plurality of transmission lights emitted from a light source without waste. It becomes possible to perform divided transmission to the partner device and to flexibly cope with a change in the number of partner devices.

Further, in the second invention of the present application, an optical signal is transmitted in an optical space communication device for performing information communication with a plurality of partner devices installed in different places by using the optical signal propagating in the air. Receiving means capable of receiving, a plurality of mirrors capable of reflecting an incident optical signal toward the receiving means are arranged in a matrix, and a movable mirror array in which the directions of the respective mirrors can be changed independently of each other. The mirror array is provided in the movable mirror array with mirror control means for controlling the direction of each mirror so as to form a plurality of mirror groups that reflect optical signals from different counterpart devices to the receiving means. The number of mirror groups can be changed.

This makes it possible to freely set the number of mirror groups that reflect the optical signals from different partner devices so as to guide the light signals to the receiving means, and to set the number of mirror groups freely. It is possible to make the received light incident on a single receiving means without waste,
It is possible to flexibly cope with a change in the number of partner devices.

In the first and second inventions described above, the same number of mirror groups as the number of partner devices can be formed. However, among all partner devices, the number of partner devices that are actually communication partners is set. It is also possible to form the same number of mirror groups as.

Further, an input means for inputting information on the direction or the position of each partner device or a detecting means for detecting the direction or position of each partner device is provided, and the mirror control means is provided with the information inputted from the above input means or the above The direction of each mirror can be controlled according to the detection result of the detection means.

If the number of mirrors belonging to each mirror group is substantially equal to each other, if the communication environment such as the presence or absence of an obstacle is the same, the communication quality is the same for a plurality of partner devices. It is possible to communicate with.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1A shows an optical space communication system according to a first embodiment of the present invention. In this figure, 10 is an optical space communication device according to the present invention, which is installed on one side of a point-to-multipoint communication, and 11a, 11b, 11c, 11d are multipoints installed at different points in a remote place. 2 shows an optical space communication device (hereinafter, referred to as a partner device).

In the optical space communication device 10, the light source 101
The optical signal emitted from is transformed by the optical system 102 into a slightly divergent, substantially parallel light beam 103. The light beam 103 is transmitted to the movable mirror array 104.
Then, four partner devices 11a, 11b, 11c, 11d
Are reflected in four different directions, respectively.

As shown in FIG. 2, the movable mirror array 104 includes a large number of mirrors arranged in a matrix (see FIG. 2).
In this example, each of the mirrors 104 a is composed of 16 × 16 mirrors) 104 a, and each of the mirrors 104 a is driven by a control signal 106 output from the mirror control circuit 105 The actuators can change the direction independently.

Here, the control of the movable mirror array 104 by the mirror control circuit 105 will be described with reference to the flowchart of FIG.

When the optical space communication device 10 is installed, the installer installs the other device 11a, 11b, 1 through the input device 110 such as a keyboard connected to the mirror control circuit 105.
When the number of 1c and 11d (four units in this embodiment) is input (step <abbreviated as S in the figure> 1), the mirror control circuit 105 moves in the movable mirror array 104 in accordance with the input number of other devices. , Mirror groups of approximately the same number belong to each other (having the same reflection area on the movable mirror array 104), and the same number of mirror groups as the number of partner devices are set (step 2).

FIG. 3 shows four mirror groups set in the movable mirror array 104. That is, the movable mirror array 1 when there are four partner devices
The state of 04 is shown. In this case, the 16 × 16 mirrors are grouped into four mirror groups A, B, C, D each consisting of 8 × 8 mirrors which are equal to each other.

The mirror group A is the partner device 11a.
Used for communication with the mirror group B,
Used to communicate with b. The mirror group C is used for communication with the partner device 11c, and the mirror group D is used for communication with the partner device 11d.

Then, in step 3, the installer inputs the directions of the partner devices 11a, 11b, 11c, 11d viewed from the optical space communication device 10 through the input device 110.
The mirror control circuit 105 allocates one mirror group to each partner device, and sets the direction of the mirrors 104a belonging to each mirror group to the direction in which the optical signal from the light source 101 is reflected toward the corresponding partner device ( The mirror groups are controlled so as to be set in the same direction or in such a direction that they are focused on the partner device (step 4).

By thus setting the orientation of the mirror 104a, the light beam 103 incident on the movable mirror array 104 is provided with the counterpart devices 11a, 11b, 11c and 11d by the four mirror groups A to D. It is split and reflected in four different directions. The reflected light beams divided into four are respectively the other devices 11a, 11b, 11
It is received by c and 11d, and point-to-multipoint communication is performed.

When changing the number of communicating devices, each mirror 1 of the movable mirror array 104 described above is used.
Control signal 1 from the mirror control circuit 105 for the direction of 04a
Change according to 06.

For example, when only two partner devices are originally installed or when transmitting to only two of the four partner devices, as shown in FIG. Mirror groups A and B are formed.
Then, the mirrors 10 belonging to the respective mirror groups
The direction of 4a is controlled so as to be set so as to reflect the optical signal from the light source 101 toward the corresponding partner device.

The light beam 103 reflected by the mirror 104a belonging to each of the mirror groups A and B travels in two different directions and is received by the corresponding counterpart device.

Comparing the case where there are four partner devices and the case where there are two partner devices, even if the number of partner devices changes, they are formed in the movable mirror array 104 by the mirror direction control of the mirror control circuit 105. Almost all emitted light from the light source 101 can be changed by changing the number of mirror groups.
It is possible to efficiently allocate each partner device without waste.

In the present embodiment, the case where there are four partner devices and the case where there are two partner devices have been described, but the number of partner devices, that is, the number of mirror groups formed in the movable mirror array 104 is this. It is not limited to.

As described above, by grouping a large number of mirrors 104a constituting the movable mirror array 104 into groups according to the number of partner devices that are actually installed or the partner devices that are actually trying to communicate, A flexible optical space communication system capable of communication can be realized by effectively utilizing the light flux from the light source 101 regardless of the number of partner devices.

Further, although the case where the number of mirrors forming the movable mirror array 104 is 16 × 16 has been described in the present embodiment, the number of mirrors forming the movable mirror array in the present invention is not limited to this.

Further, in this embodiment, the input device 110 is used.
Although the case has been described in which the number of partner devices is input through the mirror control circuit 105 and the mirror control circuit 105 sets the mirror group according to the input number, there is another method of setting the mirror group.

For example, a different number or code is assigned to each of a large number of mirrors forming the movable mirror array, and the number or code of the mirrors belonging to each mirror group is designated in the input device connected to the mirror control circuit. Can be taken. Further, the area of the mirror group belonging to each mirror group may be designated on the movable mirror array.

In this embodiment, the case where each mirror constituting the movable mirror array 104 is driven by using the actuator has been described. However, each mirror is formed on a silicon wafer and a voltage is applied to generate distortion. It is also possible to use a mirror that drives the mirror around two axes that are parallel to the mirror surface and are orthogonal to each other.

(Second Embodiment) In the first embodiment,
The case has been described in which each mirror group is formed as one group and the mirror groups are formed adjacent to each other, but as shown in FIG. 5, the mirrors 104a ′ belonging to each mirror group are movable mirror arrays 104 ′.
They may be arranged discretely (however, they may be arranged with a certain degree of regularity).

FIG. 5 shows the case where four mirror groups are formed, and the symbols A to D attached to the respective mirrors indicate the mirror groups to which the mirrors belong.

(Third Embodiment) In the first embodiment,
Although one-way communication between one-to-many points has been described as an image, the present invention can also be applied to the case where bidirectional one-to-many point-to-point communication is performed. FIG. 6 shows an optical space communication system in the image of bidirectional communication.

In this figure, 60 is installed on one side of a point-to-multipoint communication. Optical space communication devices 61a, 61b, 61c, 61d according to the present invention are installed at different points in a remote place. An optical space communication device on the multipoint side (hereinafter referred to as a partner device) is shown.

The optical space communication device 60 of this embodiment is the first
A polarization beam splitter 60 for separating a transmission optical signal and a reception optical signal is added to the components described in the embodiment.
7 and a light receiving element 608 are added.

The optical signal emitted from the light source 601 is incident on the polarization beam splitter 607. Since the incident light from the light source 601 is polarized in the direction of passing through the polarization beam splitter 607, the polarization beam splitter 6 as it is.
After passing through 07, it enters the optical system 602. Then, it is transformed by the optical system 602 into the shape of the substantially parallel light beam 103 having a slight spread and is incident on the movable mirror array 604.

The structure of the movable mirror array 604 and the orientation control of each mirror in the movable mirror array 604 by the input device 610 and the mirror control circuit 605 are the same as in the first embodiment.

As a result, the light beam 603 is transmitted by the four mirror groups formed in the movable mirror array 604 to the four mating devices 61a, 61b, 61c, 61.
d is reflected in four different directions respectively installed, and an optical signal is received by each partner device.

On the other hand, the partner devices 61a, 61b, 61
The four received lights transmitted from c and 61d are reflected toward the optical system 602 by the four mirror groups formed in the movable mirror array 604. Unlike the transmitted light from the light source 601, these received lights have a deflection direction in which they are reflected by the polarization separation surface of the polarization beam splitter 607. Therefore, the received light entering the polarization beam splitter 607 is reflected by the polarization separation surface and guided to the light receiving element 608. Thereby, the four partner devices 61a, 61b, 6
The optical signals from 1c and 61d are received by the single light receiving element 608.

As described above, according to this embodiment, the optical space communication device 60 and the plurality of partner devices 61a, 61b, 61.
Bidirectional communication with the c and 61d is possible.

When changing the number of communicating devices, the direction of each mirror of the movable mirror array 604 is controlled by the mirror control circuit 605, as in the first embodiment.
It changes according to the control signal 606 from.

As described above, by grouping a large number of mirrors forming the movable mirror array 604 into a number according to the number of the partner devices that are actually installed or the partner devices that are actually trying to communicate, the partner device Regardless of the number of optical receivers, the luminous flux for transmission from the light source 601 is effectively used, and the received light from a plurality of partner devices is not wasted, and a single light receiving element 608
It is possible to realize a flexible optical space communication system that can be made incident on the beam.

In the present embodiment, the number of communicable partner devices, that is, the maximum number of mirror groups formed in the movable mirror array 604 is not limited to four.

(Fourth Embodiment) In the first to third embodiments, the installer inputs the direction of the partner device through the input devices 110 and 610, and the mirror control circuits 105 and 605 according to the input direction information. Is a movable mirror array 104, 6
Although the case of controlling the direction of each mirror of 04 has been described, the position of the partner device (for example, latitude,
(Longitude) may be input and the orientation of each mirror may be controlled according to the input position information.

Further, instead of the installer inputting the direction and position, a detector for detecting the direction and position of the other device is provided, and the mirror control circuits 105 and 605 are movable according to the detection result of this detector. The orientation of each mirror of the mirror arrays 104 and 604 may be controlled.

[0052]

As described above, according to the first invention of the present application, the number of mirror groups that reflect optical signals toward different partner devices can be freely set according to the number of partner devices. Therefore, the transmission light emitted from the light source can be divided and transmitted to a plurality of partner devices without waste, and an optical space communication device capable of flexibly coping with the change of the number of partner devices can be realized.

Further, according to the second aspect of the present invention, the number of mirror groups that reflect the optical signals from different partner devices so as to be guided to the receiving means can be set freely according to the number of partner devices. Thus, it is possible to realize an optical space communication device capable of allowing light received from a plurality of partner devices to be incident on a single receiving means without waste and flexibly coping with the change of the number of partner devices.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an optical space communication system according to a first embodiment of the present invention and a control flowchart of a movable mirror array used in an optical space communication device configuring the optical space communication system.

FIG. 2 is an explanatory diagram showing a configuration of the movable mirror array.

FIG. 3 is a diagram showing how to group the mirrors of the movable mirror array when there are four partner devices in the first embodiment.

FIG. 4 is a diagram showing how to group the mirrors of the movable mirror array when the number of partner devices is two in the first embodiment.

FIG. 5 is a diagram showing how to group mirrors in a movable mirror array in the case where the number of partner devices is four in the optical space communication system according to the second embodiment of the present invention.

FIG. 6 is a configuration diagram of an optical space communication system according to a third embodiment of the present invention.

FIG. 7 is a block diagram of a conventional optical space communication system.

[Explanation of symbols]

10, 60 Optical space communication devices 11a, 11b, 11c, 11d, 61a, 61b, 6
1c, 61d Opposite device 101, 60 1 Light source 102, 602 Optical system 103, 603 Light beam 104, 604 Movable mirror array 105, 605 Mirror control circuit 110, 610 Input device 607 Polarizing beam splitter 608 Light receiving element

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04B 10/22 (72) Inventor Masatoshi Otsubo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 2H041 AA11 AA14 AB14 AC04 AZ05 2H042 AA30 DD04 DE07 5K002 AA01 BA21 FA03 FA04

Claims (13)

[Claims] 1. An optical space communication device for performing information communication with a plurality of partner devices installed in different places by using an optical signal propagating in the air, and a light source for emitting an optical signal, A plurality of mirrors that reflect an optical signal from a light source are arranged in a matrix, and a movable mirror array in which the directions of the respective mirrors can be controlled independently of each other; Mirror control means for controlling the direction of each of the mirrors so that a plurality of mirror groups that reflect light are formed, and the number of mirror groups formed in the movable mirror array can be changed. Optical space communication device. 2. The optical space communication device according to claim 1, wherein the movable mirror array has the same number of mirror groups as the plurality of partner devices. 3. The optical space communication according to claim 1, wherein, in the movable mirror array, the same number of mirror groups as the number of partner devices that are actually communication partners among the plurality of partner devices are formed. apparatus. 4. An input unit for inputting information on the direction or position of each of the plurality of partner devices, wherein the mirror control unit controls the direction of each mirror according to the information input from the input unit. The optical space communication device according to claim 1, wherein 5. A detection means for detecting the direction or the position of each of the plurality of partner devices is provided, and the mirror control means controls the orientation of each mirror according to the detection result of the detection means. The optical space communication device according to claim 1. 6. The optical space communication device according to claim 1, wherein the number of mirrors belonging to each of the mirror groups is substantially equal to each other. 7. An optical space communication device for performing information communication with a plurality of partner devices installed at different locations by using an optical signal propagating in the air, the receiving means capable of receiving the optical signal. A movable mirror array in which a plurality of mirrors capable of reflecting an incident optical signal toward the receiving means are arranged in a matrix, and the directions of the respective mirrors can be changed independently of each other; A mirror control unit that controls the direction of each of the mirrors so that a plurality of mirror groups that reflect optical signals from different partner devices to the receiving unit are formed, and are formed in the movable mirror array. Optical space communication device characterized in that the number of mirror groups can be changed. 8. The optical space communication device according to claim 7, wherein the movable mirror array has the same number of mirror groups as the plurality of partner devices. 9. The optical space communication according to claim 7, wherein, in the movable mirror array, mirror groups are formed in the same number as the number of partner devices that are currently communication partners among the plurality of partner devices. apparatus. 10. An input unit for inputting information on the direction or position of each of the plurality of opponent devices, wherein the mirror control unit controls the direction of each mirror according to the information input from the input unit. The optical space communication device according to claim 7, wherein 11. A detection means for detecting a direction or a position of each of the plurality of partner devices, wherein the mirror control means controls the direction of each of the mirrors according to a detection result of the detection means. The optical space communication device according to claim 7. 12. The optical space communication device according to claim 7, wherein the number of mirrors belonging to each mirror group is substantially the same. 13. An optical space communication system, comprising: the optical space communication device according to claim 1; and a plurality of partner devices installed at mutually different locations. .