OA11391A - Reflector-sensor with photovoltaic cells and communication system comprising such a reflector-sensor. - Google Patents

Abstract

The invention concerns a reflector-sensor for receiving/transmitting electromagnetic waves respectively from and to a satellite and for collecting and converting an amount of solar energy into electric power, said reflector-sensor comprising a reflecting surface (2) equipped with a plurality of photovoltaic cells (4) and at least an electronic head (6) receiving/transmitting E.M. waves, said photovoltaic cells (4) are transparent to E.M. waves and are fixed on the greater part of the reflecting surface (2) such that the reflector-sensor operates both as receiver/transmitter antenna and solar energy collector (4). The invention is characterised in that said photovoltaic cells are integrated in the reflecting surface (2) between a first layer (10) transparent to E.M. waves and to solar radiation for protecting said cells (4) and a second layer (12) for reflecting the E.M. waves.

Description

011591

PHOTOVOLTAIC CELL SENSOR REFLECTOR AND COMMUNICATION SYSTEM COMPRISING SAME

The present invention relates to a reflector-sensor capable of transmitting / receiving electromagnetic waves (E.M.) to / from a source and capturing and converting a quantity of solenoidal radiation into electrical energy. The reflector-sensor, which is the subject of the invention, thus performs the functions of transmitting / receiving and solar collector antenna, and for this purpose comprises a reflection surface provided with a plurality of photovoltaic cells, transparent to the electromagnetic waves, fixed on the bulk of said surface and at least one electronic head intended for transmission / reception of electromagnetic waves to / from a satellite, and for frequency conversion of the received or transmitted signals. The invention also relates to a communication system with a satellite comprising a sensor-reflector.

The reception and transmission of information is increasingly taking place via satellites25 both in the field of telecommunications and in the field of television. These transmissions require the use of antennas, generally parabolic, associated with frequency converters and modulators / demodulators. These antennas require, for their operation, a power supply which is generally provided by the electricity network, which means that they can not be used in places for which connection to the electricity grid is not possible for economic reasons or for reasons of difficulty. implemented, for example, in isolated locations such as mountains.

An antenna with solar collectors is described in Japanese Patent 61-070804A. These sensors 5 are arranged on the periphery of the antenna and can capture only a limited amount of solar radiation used exclusively to supply the frequency converter of the antenrte.

The object of the invention is to provide a reflector-sensor capable of providing sufficient electrical power to supply both the frequency converter and the electronic data processing equipment exchanged with the satellite associated with the reflector-sensor while ensuring a transmission and / or efficient reception of electromagnetic waves.

Another object of the invention is to provide a complete, completely autonomous communication system that can be used in isolated locations not connected to an electrical network.

These objects are achieved by means of a reflector-sensor whose reflection surface is provided with a plurality of photovoltaic cells transparent electromagnetic waves, and fixed on the major part of said reflection surface characterized by the fact that the photovoltaic cells are incorporated in the reflection surface between a protective layer transparent to electromagnetic waves and solar radiation and a metal layer 30 reflecting the EM waves

Thanks to this structure, the sensor-reflector according to the invention is capable of converting a quantity of solar radiation sufficient to supply power to a complete communication system. In addition, photovoltaic cells are effectively protected against corrosion. 3 011L9Î

Advantageously, the photovoltaic cells are polycrystalline silicon or monocrystalline oramorphous. They may also be Galium arsenide or any other material exhibiting the photocell phenomenon.

The communication system according to the invention comprises such a sensor reflector and can be used bothin locations not connected to an electrical network and in places where the use of an electrically autonomous device is more economical than connecting to a remote control. Other features and advantages of the invention will emerge from the description which follows, taken by way of non-limiting example, with reference to the appended figures in which: FIG. 1 represents a perspective view of a reflector; sensor according to the invention; Figure 2 shows a sectional sectional view of the reflection surface of the reflector-sensor of Figure 1; FIG. 3 represents a reflecting surface of a reflector-sensor according to the invention; FIGS. 4 and 5 schematically illustrate two particular modes of arrangement of the photovoltaic cells on a reflector-sensor according to the invention; FIG. 6 partially and schematically illustrates a reflector-sensor, according to a particular embodiment, in the transmission / reception position; FIG. 7 schematically represents a first example of a communication system comprising a reflector-sensor according to the invention; FIG. 8 represents a second example of the communication system comprising a reflector-sensor according to the invention; FIG. 9 represents a third example of a communication system ... comprising a reflector-sensor according to the invention; FIG. 10 represents a fourth exemplary communication system comprising a sensor-sensor according to the invention; FIG. 1 shows a sensor reflector adapted to transmit / receive electromagnetic waves to / from a geostaticnary satellite and to capture andconvert a quantity of solar radiation into electrical energy.

The reflector-sensor i comprises a reflection surface 2 provided with a plurality of photovoltaic cells 4, an electronic head 6 for emitting / receiving electromagnetic waves. According to an essential characteristic of the invention, the photovoltaic cells 4 are transparent to the EM waves and, as can be seen in FIG. 1, are fixed on the major part of the reflection surface 2. According to a preferred embodiment of the invention, FIG. The invention illustrated in FIG. 2, the photovoltaic cells 4 are incorporated in the reflection surface between a layer 10 transparent to electromagnetic waves and solar radiation and intended to protect said photovoltaic cells 4 and a metallic layer 12 intended to reflect the wavesE.M . .

Preferably, the protective layer 10 is made of polycarbonate or polyester, however it can be made from other materials (glass for example) 'having the necessary qualities for the mechanical holdings (stresses, shocks, ...) etthermiques , as well as a high transparency to solar radiation and EM waves.

The photovoltaic cells 4, as can be seen in FIG. 2, are connected by connection wires 13. The frame 14 of the reflector-sensor 1 has the shape of an off-center paraboloid and is preferably made of fiber-reinforced polyester. 10 of glass. It can also be metallic.

The electronic head 6 is mechanically connected to the reflection surface 2 by an arm 16.

A module 1S for storing and managing the electrical energy supplied by the photovoltaic cells 4 is connected, on the one hand, to said cells by a first coaxial cable 19a and, on the other hand, to the electronic head 6 by a second cable, coaxial 19b. The module 18 for storing and managing electrical energy may be connected by a third cable 19c and by a fourth cable 19d to any apparatus associated with the sensor reflector 1 and requiring an electrical power supply.

As can be seen in FIG. 2, the photovoltaic cells 4 are embedded in a fastening material 20, also transparent to the EM waves. and solar radiation, thus ensuring theirfixation between the protective layer 10 and the 12th metal. This material is preferably in ethyl-vinyl-acetyl. FIGS. 3 and 4 illustrate two embodiments of the invention, in which the sensor reflector 1 has a parabolic shape and the photovoltaic cells 4 are distributed between a plurality of adjacent zones A, B, C and D for FIG. 3 and A, B, C, D and E for FIG. 4. These areas cover the largest part of the reflection surface 2, and are interconnected in parallel, while the photovoltaic cells 4 of each zone are connected in series. Measurements have shown that this arrangement makes it possible to optimize the electrical power converted by the cells 4.

In a particular embodiment of the invention, the number of zones is 4 and the number of cells per zone is 18. "

FIG. 5 shows a reflector-sensor 10 according to the invention having a parabolic shape and whose reflection surface 2 has a diameter of 80 cm. As can be seen in FIG. 5, sixty-four photovoltaic cells 4 made of silicon polycrystalline are fixed on this surface. Electric power Λ ··. . / 15 issued. the module 18 associated with this reflector-sensor is about 45 W at a voltage of 6 V or 12 V.

It should be noted that, for a given geographical area, the geostationary satellites are positioned above the equator in a plane substantially perpendicular to the average surface of this zone. This azimuth orientation corresponds to optimum solar radiation. As a result, adjustment of the surface of the reflector-sensor 1 in elevation and in azimuth has the effect of systematically orienting said surface towards the direction where the solar radiation near the optimum. The following arrangement is intended to optimize the elevation angle of the surface of reflector-sensor 1. In the operating position, as schematically illustrated in FIG. 6, the axis Δ of the parabola must be oriented precisely towards a satellite. . The quality of the transmissions depends on the accuracy with which the antenna points the satellite and therefore on the elevation angle α of the Δ axis. This angle depends on the transmission site. The amount of solar radiation captured by the sensor reflector depends on the angle of inclination, relative to the horizontal, of the reflection surface exposed to the radiation. A variation of the angle "causes a variation of the angle Θ and vice versa. This means that the positioning of the dish must allow an optimization of the amount of radiation captured and an effective transmission. <

For each location, there is an optimal angle O opt for which the uptake of solar radiation during one year is optimal.

Considering the largest portion ab of the reflection surface which, in a working position, is exposed to solar radiation, the average angle of inclination of this portion is Θ. As can be seen in FIG. Θ is correlated with the elevation angle α by the relation. δ = 180 - (α + Θ) where 20 δ represents the average angle of construction of the reflector-sensor formed between the Δ axis of the parabola and the axis passing respectively by the upper and lower limits b of the portion exposed to the solar radiation . This angle δ depends on the choice of this portion of the parabola which receives the solar radiation and is therefore a characteristic of construction of the sensor-reflector 1.

In order to optimize the amount of radiation captured in a given location for a year, the angle of δ of construction of the reflector-sensor according to the invention is calculated so that the angle of inclination Θis approximately equal to the optimum angle 6.option of solar radiation irrespective of the location of use of the reflector-sensor 1. For example, when the reflector-sensor 1 is pointed at the Astra satellite at 19.2 ° East: - A STOCKHOLM - A LILLE: <x = 24 °,: a = * 30 °, 6 = 8 6 ° 0 = 80 ° and 0opt = 85o and 0opt = 80 ° about 5 - A NICE: a = 38 °, e = 72 ° and 0Opt = about 70 ° The reflector-sensor 1 according to the invention can be used in several different applications that will be described in the following description *

In a first example of an application, illustrated schematically in FIG. 7, a communication system with a satellite comprises a sensor reflector 1 according to the invention connected to a module 18 for the clearance and management of electrical energy. Lemodule 18 is connected, on the one hand, to the transmission head 15 / reception 6, and on the other hand, to an electronic assembly 32 for processing information transmitted to the satellite and information received from said satellite. The electronic assembly 32 comprises, in a manner known per se, a modulator for transmission, a demodulator for reception as well as amplification and error correction equipment in the case of digital transmissions.

The modulator and the demodulator can advantageously be grouped together in the same apparatus.

The communication system further comprises one or more data acquisition members 34 to be transmitted, connected to the modulator / demodulator and one or more display members 36 of the received information.

The input devices may include a camera for the image, a microphone for the sound, a keyboard for the data, while the organs for previewing may comprise a conventional television screen, a computer screen serving at the same time as a entry. 9 011391

In a second example of an application illustrated in FIG. 8, the communication system fulfills the function of a relay and comprises for this purpose an antenna 40, which may be a terrestrial antenna or a parabolic antenna, intended to retransmit, in a frequency band. adapted to the intended application, the information received by satellite. Such a device finds its application in the wireless distribution of information received, to several terminals or 10 receiving stations. This may be of interest to the individual habitat in which there are several receivers, such as televisions, computers, or collective housing. The communication system shown in FIG. 8 can also be used in cellular telecommunications either in the context of networks managed by telecommunication operators or in the context of private or collective installations. This system can be installed at any point of the territory without any infrastructure equipment and has total energy autonomy thanks to the energy storage module 18.

In a third exemplary application illustrated by FIG. 5, the communication system 25 'fulfills only the information transmitter function and comprises for this purpose a sensor reflector 1 according to the invention connected to a module 18 for storage and management. The module 18 is connected, on the one hand, to the transmit / receive head 6, and on the other hand, the electronic information processing unit 32 to transmit to the satellite. In this example of application, the electronic assembly 32comporte, in a manner known per se, a modulator connected to the transmitting / receiving head 6 via the cable 19c. One or more information input systems (audio, visual, technical data, etc.) can be connected to the electronic assembly 32 via connection points provided for this purpose.

It should be noted that the two communication systems illustrated by FIGS. 8 and 9 can be grouped together in a single unit in order to constitute a single system fulfilling the relay function and the transmission / reception of information to / from unsatellite. ,

In a fourth exemplary application 10 illustrated in FIG. 10, the communication system is a terminal for visual and sound information that can be consulted, for example, to provide meteorological conditions in the mountains and at the edge of the sea, tourist information with information banks. data updated continuously.

The communication systems described above may furthermore be provided with a device for orienting the reflector-sensor 1, also powered by the storage module 18. The orientation device comprises, in a manner known per se, a remote-controlled motor The orientation can also be slaved to perform automatic repointing on a satellite in the case of a shipboard system, for example, or in the case of transmissions. infrequently, the reflection surface 2 then following the trajectoire of the sun and then repointed on a satellite. In another constructive arrangement of the reflector-sensor according to the invention, the reflective surface 2 can be designed to receive simultaneously a plurality of satellites.

Note that the reflector-sensor 1 can be replaced by a network antenna comprising a group of radiating elements distributed on its reflection surface, and a plurality of photovoltaic cells transparent to electromagnetic waves evenly distributed on the surface of reflection .

In operation, -163 photovoltaic cells transform the solar radiation captured into electrical energy which is stored in the module 18. This latter supplies current to the transmission / reception head 6 as well as the electronic assembly 32 thus conferring on the communication system a total autonomy. The storage and electrical energy management module 18 can separately or simultaneously select one or more areas A, B, C, D, or E from the reflection surface 2. Other applications of the communication system according to the invention can relate to security against the fire, the dela etc ... flight, storm,

Claims (11)

12 011391 CLAIMS 1. Reflector-sensor (1) able to receive / emit electromagnetic waves 5 from and to a satellite respectively and to capture andconvert a quantity of solar radiation into electrical energy, said reflector-sensor (1) comprising a reflection surface ( 2) provided with a plurality of photovoltaic cells (4) transparent to the EM waves, fixed on the major part of said reflection surface (2), and at least one electronic EM transmitting / receiving head (6), characterized in that said photovoltaic cells (4) are incorporated in the reflection surface (2) between a first transparent electromagnetic and solar radiation protective layer (10) and a second metal layer (12) for reflecting the electromagnetic waves. 20 25 30 2. Reflector-sensor (1) according to claim 1, characterized in that the photovoltaic cells are coated in a fixing material (20) also transparent to solar radiation and E.M.Waves emitted by the satellite. 3. Reflector-sensor (1) according to one of claims 1 or 2, characterized in that anglemoyen O formed between the axis .... passing by the lower limit a and the upper limit b of the portion of the surface ( 2) which is exposed to solar radiation and the axis Δ passing through the center of said surface (2) isthat in the transmit / receive position, the inclination angle Θ of said portion is approximately equal to the angle for which the the amount of solar radiation picked up is optimal whatever the angle of elevation of the Δ axis. 35 13 011391 4. Reflector-sensor (1) according to claim 2 characterized in that the photovoltaic cells (4) are distributed over a plurality of zones A, B, C, D and 5 E grouped in parallel and covering most of the reflection surface (2), the cells of each zone A, B, C, D and E being connected in series. 5. Reflector-sensor according to any one of claims 1 to 4 characterized in that the reflection surface (2) has a paraboloidal shape. 6. Reflector-sensor (1) according to claim 5, characterized in that the reflection surface 15 has a shape adapted to receive and / or emmtresimultaneously information to several satellites. 7. Reflector-sensor (1) according to claim 4, characterized in that the photovoltaic cells (4) are made of polyscrystalline silicon. 8. Reflector-sensor (1) according to claim 2, characterized in that the fixing material of the photovoltaic cells and the protective layer (10) are made of ethyl-vinyl-acetyl and the protective layer (10) is made of polycarbonate . 9. Communication system, characterized in that it comprises a sensor-reflector (1) according to one of claims 1 to 8. 10 communication system according 9 claim 9, characterized in that it further comprises a module (18) for storing and managing electrical energy connected to the reflecting reflector (1). A communication system according to claim 10, characterized in that the storage and power management module (18) supplies, on the one hand, the electronic transmission / reception head (6) and, on the other hand, the electronic transmission / reception head (6). on the other hand, an electronic assembly (32) processing information emitted / received by the transmitting / receiving electronic head (6). Communication system claim 11, characterized in thatelectronics (32) comprises a modulation / demodulation unit connected, on the one hand, to the transmit / receive head (6), and, on the other hand, to an input member (34) for the information to be transmitted. according to all1 13 communication system according larevendication 12 characterized in that it further comprises a member (36) for viewing information 20 transmitted and received by the transmitting / receiving head connected to the modulator / demodulator. Communication system according to claim 9, characterized in that it comprises an antenna (40) for retransmitting the information received by the transmitting / receiving head (6) to one or more earth receiving stations. 15. An electronic information terminal, characterized in that it comprises a communication system according to one of claims 10 to 14. 16. Reflector-sensor (1) able to receive / emit electromagnetic waves 35 respectively from and to a satellite and to capture andconvert a quantity of solar radiation into electrical energy comprising an area (2) for solar radiation capture and transmission / reception of EM waves, characterized in that said surface (2) comprises a group of radiating elements and a plurality of 5. photovoltaic cells u (4) transparent to electromagnetic waves distributed over most of said surface (2).