CA2307382C - Wireless data communications network and method for operating the data communications network - Google Patents
Wireless data communications network and method for operating the data communications network Download PDFInfo
- Publication number
- CA2307382C CA2307382C CA002307382A CA2307382A CA2307382C CA 2307382 C CA2307382 C CA 2307382C CA 002307382 A CA002307382 A CA 002307382A CA 2307382 A CA2307382 A CA 2307382A CA 2307382 C CA2307382 C CA 2307382C
- Authority
- CA
- Canada
- Prior art keywords
- data
- optical
- communications network
- data communications
- flying objects
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/11—Arrangements specific to free-space transmission, i.e. transmission through air or vacuum
- H04B10/112—Line-of-sight transmission over an extended range
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/185—Space-based or airborne stations; Stations for satellite systems
- H04B7/18502—Airborne stations
- H04B7/18504—Aircraft used as relay or high altitude atmospheric platform
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Electromagnetism (AREA)
- Astronomy & Astrophysics (AREA)
- Aviation & Aerospace Engineering (AREA)
- General Physics & Mathematics (AREA)
- Radio Relay Systems (AREA)
- Optical Communication System (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
The present invention relates to a data communications network and a method for operating the data communications network, wherein the data communications network essentially consists of fixed stations on or near the ground and freely movable flying objects, which are linked together by means of wireless data links. The concept of the invention is based on interruption-free optical laser communications between various flying objects, which typically operate above the cloud tops. These laser-optical data links offer the greatest degree of interception security, and in addition can be advantageously built up or changed very rapidly.
Since the individual flying objects operate independently of each other over a wide range, a maximal autonomy of the communications network can be assured. In particular is it possible by means of this to reconfigure the data communications network very rapidly and to adapt it in this way to changed conditions. Moreover, redundancy, and therefore greater flexibility in the topology of the data communications network, can be created by the use of additional flying objects.
Since the individual flying objects operate independently of each other over a wide range, a maximal autonomy of the communications network can be assured. In particular is it possible by means of this to reconfigure the data communications network very rapidly and to adapt it in this way to changed conditions. Moreover, redundancy, and therefore greater flexibility in the topology of the data communications network, can be created by the use of additional flying objects.
Description
Wireless Data Communications Network and Method for Operating the Data Communications Network 2 o FIELD OF THE INVENTION
The invention relates to a wireless data communications network in accordance with the preamble of claim 1, and a method for operating the data communications network in accordance with the preamble of claim 9.
BACKGROUND OF THE INVENTION
It is known in connection with wireless data communications networks to transmit the data 3 0 to be transmitted without the interposition of a conducting medium, for example an electrical conductor or a glass fiber. Here, the data to be transmitted are forwarded by means of suitably modulated electromagnetic or optical waves.
-.2.-Data transmission methods by means of high-frequency electromagnetic waves are known in a number of variations and are presently employed in telecommunications in particular. For example, telephone calls from the fixed network or mobile radio network can be transmitted extra-terrestrially over short to medium ranges. Further than that, this data transmission method has been successfully used for over 20 years for transmitting information from satellites over long distances. At present, satellite transmissions are in particular used for the transmission of radio and broadcast frequencies, but also for intercontinental telephone transmissions.
Wireless optical data transmission methods are operated by means of data-modulated laser pulses. In comparison with high- frequency radio link connections, the optical free space connections have been shown to be very advantageous for data transmissions for various reasons. For example, because of its extremely short wavelength, an optical laser beam can be very easily radiated by means of a relatively small optical transmission device and therefore at a very small spatial angle.
In contrast to the above mentioned radio link connections, it is possible because of this good focusing ability of the laser beam to employ very small transmitting stations and receiving antennas in the course of optical data transmissions. With these minimalized optical 2 0 antennas considerably larger data rates can be transmitted at a minimal transmitting output than it would be possible, for example, with data transmissions by means of radio link systems at the same transmitting output. Moreover, optical data transmission methods advantageously have almost no background signal noise.
2 5 The good focusing ability, or respectively capability for bundling, of the optical transmission beam, however, requires an extremely precise determination of the direction of the transmitted beam in the transmitting station, as well as exact tracking and alignment of the optical receiver device in the receiving station. Moreover, the problem arises in optical free space data communications in particular, that at least one of these 3 0 stations is arranged freely movable in space, which makes leading the optical laser beam in respect to the optical receiver device necessary. A method and an arrangement for the disruption- free operation of optical data links between satellites, wherein a laser beam is employed for the data transmission between the respective satellites, is described in EP 0 876 013 A1.
-.3.-Besides a high data transmission rate, the lowest possible energy use of the transmittinglreceiving stations, and a data transmission as free as possible of signal noise, additional requirements are being made on data communications networks in accordance with the species, in particular by military air and space technologies.
For military reconnaissance, or respectively information transmission in crisis or war zones, the data communications network employed there must assure the highest degree of freedom from interception and interference with the data transmissions.
Although as a rule an existing communications network is present in such crisis or war zones, it is not to l0 be used, especially for reasons of a deficient or lacking interception security. Up to now a satellite-supported data communications system had therefore been used as an obvious solution, wherein the data to be transmitted are sent from a ground-supported or aircraft-supported transmitting station via satellites to the receiving station. In this case data transmission occurs via radio signals. However, it was shown that this data transmission system is not one hundred percent secure from being intercepted, and that moreover it can be interfered with, or respectively disrupted, by third parties in an undesirable manner.
It is furthermore of decisive importance that an interception-free communications 2 0 network can be established very quickly and with simple means. This communications network should be operable nearly independently of the existing infrastructure. Moreover, a change in the situation can for example make it necessary to change the structure of the data communications network, which makes a certain degree of flexibility of the network topology used desirable.
Such a data communications network meeting the requirements mentioned could not be satisfactorily realized up to now.
Based on this, the object of the present invention is to make available a universally 3 0 usable data communications network which is secure against interception and interruption to the highest possible degree, which moreover is suitable for data transmissions at a high information density. Furthermore, it is intended to make available a method for operating this data communications network.
The invention relates to a wireless data communications network in accordance with the preamble of claim 1, and a method for operating the data communications network in accordance with the preamble of claim 9.
BACKGROUND OF THE INVENTION
It is known in connection with wireless data communications networks to transmit the data 3 0 to be transmitted without the interposition of a conducting medium, for example an electrical conductor or a glass fiber. Here, the data to be transmitted are forwarded by means of suitably modulated electromagnetic or optical waves.
-.2.-Data transmission methods by means of high-frequency electromagnetic waves are known in a number of variations and are presently employed in telecommunications in particular. For example, telephone calls from the fixed network or mobile radio network can be transmitted extra-terrestrially over short to medium ranges. Further than that, this data transmission method has been successfully used for over 20 years for transmitting information from satellites over long distances. At present, satellite transmissions are in particular used for the transmission of radio and broadcast frequencies, but also for intercontinental telephone transmissions.
Wireless optical data transmission methods are operated by means of data-modulated laser pulses. In comparison with high- frequency radio link connections, the optical free space connections have been shown to be very advantageous for data transmissions for various reasons. For example, because of its extremely short wavelength, an optical laser beam can be very easily radiated by means of a relatively small optical transmission device and therefore at a very small spatial angle.
In contrast to the above mentioned radio link connections, it is possible because of this good focusing ability of the laser beam to employ very small transmitting stations and receiving antennas in the course of optical data transmissions. With these minimalized optical 2 0 antennas considerably larger data rates can be transmitted at a minimal transmitting output than it would be possible, for example, with data transmissions by means of radio link systems at the same transmitting output. Moreover, optical data transmission methods advantageously have almost no background signal noise.
2 5 The good focusing ability, or respectively capability for bundling, of the optical transmission beam, however, requires an extremely precise determination of the direction of the transmitted beam in the transmitting station, as well as exact tracking and alignment of the optical receiver device in the receiving station. Moreover, the problem arises in optical free space data communications in particular, that at least one of these 3 0 stations is arranged freely movable in space, which makes leading the optical laser beam in respect to the optical receiver device necessary. A method and an arrangement for the disruption- free operation of optical data links between satellites, wherein a laser beam is employed for the data transmission between the respective satellites, is described in EP 0 876 013 A1.
-.3.-Besides a high data transmission rate, the lowest possible energy use of the transmittinglreceiving stations, and a data transmission as free as possible of signal noise, additional requirements are being made on data communications networks in accordance with the species, in particular by military air and space technologies.
For military reconnaissance, or respectively information transmission in crisis or war zones, the data communications network employed there must assure the highest degree of freedom from interception and interference with the data transmissions.
Although as a rule an existing communications network is present in such crisis or war zones, it is not to l0 be used, especially for reasons of a deficient or lacking interception security. Up to now a satellite-supported data communications system had therefore been used as an obvious solution, wherein the data to be transmitted are sent from a ground-supported or aircraft-supported transmitting station via satellites to the receiving station. In this case data transmission occurs via radio signals. However, it was shown that this data transmission system is not one hundred percent secure from being intercepted, and that moreover it can be interfered with, or respectively disrupted, by third parties in an undesirable manner.
It is furthermore of decisive importance that an interception-free communications 2 0 network can be established very quickly and with simple means. This communications network should be operable nearly independently of the existing infrastructure. Moreover, a change in the situation can for example make it necessary to change the structure of the data communications network, which makes a certain degree of flexibility of the network topology used desirable.
Such a data communications network meeting the requirements mentioned could not be satisfactorily realized up to now.
Based on this, the object of the present invention is to make available a universally 3 0 usable data communications network which is secure against interception and interruption to the highest possible degree, which moreover is suitable for data transmissions at a high information density. Furthermore, it is intended to make available a method for operating this data communications network.
The object in regard to the arrangement is attained in accordance with the invention by means of a data communications network.
In accordance with this, a wireless data communi-cations network is provided, wherein a plurality of flying objects capable of changing their positions are located in a common, limited area in the earth's atmosphere or at the distance of the earth atmosphere from the surface of the earth, can be connected with each other by means of an optical transceiver station in each flying object, each of which can be connected interference-free by means of first wireless data links which are designed at least partially as laser-optical data links using a broadband laser beam having a minimal angle of divergence to assure an interruption secure and interference secure data, and by the network having at least one fixed station on or near the ground, which can be connected with at least one transceiver station via second wireless links wherein:
at least one of the transceiver stations is designed for bi-directional data transfer and has an optical receiving unit and an optical transmitting unit for this purpose, the optical transmitting unit containing means for optical data modulation, a laser unit and an optical output amplifier for transmitting data-modulated laser signals and the optical receiving unit having a reception amplifier and means for optical data modulation, the transceiver stations having means for position stabilization and means for tracking the optical beam and at least one of the transceiver stations is seated freely pivotable in space in such a way that this transceiver - 4a -station can be coupled via first data links with any arbitrary transceiver station.
The object is regard to the method is attained by a method for operating a data communications network which includes the following method steps:
(a) a data transfer is performed between at least two transceiver stations, each provided in flying objects, via the first data links, wherein an optical laser signal is used at least in sections for the data transfer, (b) then a wireless data transfer between at least one transceiver station and a station on near the ground takes place via the second data links, wherein a data signal is received-f~om the respective transceiver station andJor is transmitted to the respective transceiver station.
The dependent claims are directed to preferred embodiments and further developments of the invention.
Tile present invention describes an optical data communications network, which is based on fixed stations on, or near the ground, and non-stationary flying objects, which are connected~with each other via wireless~data links and therefore constitute a communications network which is freely configurable over a wide range. This data -.~J.-communications network meets the demands mentioned at the outset, which are made on data communications particularly in crisis or war zones, and permits a linkage of the input and output signals of the data communications network which is free of electrical feedback.
The proposed concept is essentially based on interruption- free optical laser communications between different flying objects operating above the cloud tops. These laser-optical data links offer the greatest amount of interception security, and can furthermore be advantageously established, or changed very rapidly. This data 1 o communications network, which is a competitor of satellite-supported communications networks, can, in contrast to the latter, be installed with comparatively simple and cost-effective means. Only at least two flying objects are required for the build-up of such a data communications network, besides the stations on or near the ground. Since the individual flying objects, each of which represents the network linkages of the data communications network, can operate independently of the other within wide limits, a maximal autonomy of the network linkages can be assured. In particular, by means of this the data communications network can be very rapidly reconfigured and adapted to changes in this way. By employing additional flying objects it is also possible to generate redundancy, and therefore greater flexibility in the topology of the data communications 2 0 network.
Further details and advantages of the invention will be explained in what follows by means of two exemplary embodiments. The invention will be explained in greater detail in what follows by means of the exemplary embodiments represented in the drawings.
2 5 Shown are here in:
Fig. 1, a first exemplary embodiment of a data communications network in accordance with the invention, 3 o Fig. 2, a second exemplary embodiment of a data communications network in accordance with the invention, Fig. 3, a diagram indicating the maximum track distances as a function of the cloud tops and the flight level of the aircraft.
-.6.-Equal or functionally equal elements are provided with the same reference numerals in all drawing figures.
Fig. 1 represents a first data communications system in accordance with the invention, which is built up by means of aircraft. Two aircraft flying at high altitude are identified by 11, 12 in Fig. 1. Optical receiver stations 21, 22 have been installed in each aircraft 11, 12. The transceiver stations 21, 22 are directly coupled with each other by means of an optical data link 31. Furthermore, a base station 61, which is arranged on the surface 51 of the earth, is provided which, in the present case, is connected via a 1 o further data link 71 with an aircraft 11.
An interruption-free optical data link 31 is essential for this coupling of the transceiver stations 21, 22. For this reason, the two aircraft 11, 12 and the data link 31 connecting them, have been arranged above the cloud tops in the present example. Here, the flight level of the aircraft was identified as d3, the distance of the aircraft from each other as d1, and the cloud tops as d2.
The transceiver stations 21, 22 can be designed for bidirectional or unidirectional data transfer, i.e. for transmitting and/or receiving optically modulated data, wherein the 2 0 data to be transmitted are modulated in the form of a broadband laser beam. The optical transmitting unit of a transceiver station 21, 22 designed for transmitting contains means for the optical transmission of the data, a laser unit and an optical output amplifier. As a rule, an optical receiving unit of a transceiver station 21, 22 designed for receiving has a reception amplifier and means for optical data transfer. Furthermore, the transceiver stations 21, 22 have means for position stabilization, as well as means for tracking the optical beam. By means of this it is possible to assure that an interruption-free data link 31 is assured in case of slight vibrations, or respectively relative movements of the transceiver stations 21, 22 in respect to each other. The optical transmitting and receiving devices of a transceiver station 21, 22 are advantageously arranged so they are 3 0 freely pivotable in space, so that they can build up interruption-free data links with other, also freely movable transceiver stations 21, 22.
_ 7 _ The structure and functioning of such transceiver stations is exactly described in EP 0 847 150 A1 and EP 0 863 627 A1.
The functioning of the data communications network from Fig. 1 will be briefly described in what follows.
The first aircraft 11 in the example shown is located above a partial area 52 of the surface of the earth, while the second aircraft 12 is located above an area far distant from the partial area 52. The partial area 52 can be, for example, a crisis or war zone, above which the first aircraft 11 flies for the purpose of aerial reconnaissance. The data obtained from this aerial reconnaissance are l0 transmitted from the first transceiver station 21 to the second transceiver station 22 in the second aircraft 12 via a broadband data-modulated laser beam. It is advantageously possible to transmit data at transmission rates far above 100 Mbic/sec by means of this broadband laser beam. The data-modulated laser beams have a minimal angle of divergence and prevent therefore an undesired radiation. It is possible to assure by means of this type of data transmission that an interception-secure and interference-secure data transmission takes place at least above the partial area 52.
The demodulated data can be transmitted from the second aircraft 12 via a further 20 data link 71 to the station 61 on or near the ground. The data transmission via the second data link 71 can take place by means of radio signals, since in the case shown the ground station is located far outside the partial area 52, so that here a reduced requirement for interFerence, or respectively interception security of the data transmission results. However, an optical data transmission between the aircraft 12 and the station 61 on or near the ground would be conceivable.
Fig. 2 shows a second exemplary embodiment of a data communications network in accordance with the invention. Here, three aircraft 11, 12, 13 are provided, whose transceiver stations (not represented in Fig. 2) are respectively connected with each other via data links 31, 32. Two ground stations (or stations near the ground) 61, 62 are additionally represented, which are respectively connected with one of the aircraft 11, 12 via further data links 71, 72. A closed data communications network can therefore be -.8.-created in the example represented in Fig. 2, wherein a completely interception-secure and interference-secure data transmission between two ground stations 61, 62 is possible over very large distances.
Figs. 1 and 2 show that it is possible to create any arbitrary data communications networks in accordance with the invention in that any arbitrary number of aircraft 11, 12, 13 and ground stations 61, 62 are suitably connected by means of laser-optical data links. As already mentioned, an interruption-free optical data link 31, 32 is essential for the functioning of the data communications network. An optical link which is interruption-l0 free over great distances, can typically, but not necessarily, be assured above the cloud tops 41. For this reason the aircraft 11, 12, 13 connected with each other via data links 31, 32 must fly at least high enough that the respective data links 31, 32 between them are dependably arranged above the cloud tops 41 (d4 > d2).
Fig. 3 shows a diagram indicating the maximum track distances (d1 ) between two aircraft as a function of the flight level (d3) and the cloud tops (d2). It turns out that, with assumed cloud tops at 12 km and a flight level of 16 km, a maximum distance of approximately 500 km results between the two aircraft, while at a flight level of 30 km the free distance nearly doubles.
To create the data communications network in accordance with the invention, aircraft 11, 12, 13 were used in Figs. 1 and 2, which are designed for flying at great altitude.
Such high- altitude aircraft, which as a rule are jet-propelled, have a service ceiling which mostly lies high above the maximum cloud tops. However, in every case the aircraft 2 5 should have a ceiling of more than 12,000 m. It would also be conceivable to use captive balloons in place of aircraft. Very great altitudes, as far as up into the stratosphere, can be attained by means of captive balloons.
However, these aircrafts can also be designed as so-called unmanned drones, such 3 o as are often employed for reconnaissance purposes in crisis zones.
In accordance with this, a wireless data communi-cations network is provided, wherein a plurality of flying objects capable of changing their positions are located in a common, limited area in the earth's atmosphere or at the distance of the earth atmosphere from the surface of the earth, can be connected with each other by means of an optical transceiver station in each flying object, each of which can be connected interference-free by means of first wireless data links which are designed at least partially as laser-optical data links using a broadband laser beam having a minimal angle of divergence to assure an interruption secure and interference secure data, and by the network having at least one fixed station on or near the ground, which can be connected with at least one transceiver station via second wireless links wherein:
at least one of the transceiver stations is designed for bi-directional data transfer and has an optical receiving unit and an optical transmitting unit for this purpose, the optical transmitting unit containing means for optical data modulation, a laser unit and an optical output amplifier for transmitting data-modulated laser signals and the optical receiving unit having a reception amplifier and means for optical data modulation, the transceiver stations having means for position stabilization and means for tracking the optical beam and at least one of the transceiver stations is seated freely pivotable in space in such a way that this transceiver - 4a -station can be coupled via first data links with any arbitrary transceiver station.
The object is regard to the method is attained by a method for operating a data communications network which includes the following method steps:
(a) a data transfer is performed between at least two transceiver stations, each provided in flying objects, via the first data links, wherein an optical laser signal is used at least in sections for the data transfer, (b) then a wireless data transfer between at least one transceiver station and a station on near the ground takes place via the second data links, wherein a data signal is received-f~om the respective transceiver station andJor is transmitted to the respective transceiver station.
The dependent claims are directed to preferred embodiments and further developments of the invention.
Tile present invention describes an optical data communications network, which is based on fixed stations on, or near the ground, and non-stationary flying objects, which are connected~with each other via wireless~data links and therefore constitute a communications network which is freely configurable over a wide range. This data -.~J.-communications network meets the demands mentioned at the outset, which are made on data communications particularly in crisis or war zones, and permits a linkage of the input and output signals of the data communications network which is free of electrical feedback.
The proposed concept is essentially based on interruption- free optical laser communications between different flying objects operating above the cloud tops. These laser-optical data links offer the greatest amount of interception security, and can furthermore be advantageously established, or changed very rapidly. This data 1 o communications network, which is a competitor of satellite-supported communications networks, can, in contrast to the latter, be installed with comparatively simple and cost-effective means. Only at least two flying objects are required for the build-up of such a data communications network, besides the stations on or near the ground. Since the individual flying objects, each of which represents the network linkages of the data communications network, can operate independently of the other within wide limits, a maximal autonomy of the network linkages can be assured. In particular, by means of this the data communications network can be very rapidly reconfigured and adapted to changes in this way. By employing additional flying objects it is also possible to generate redundancy, and therefore greater flexibility in the topology of the data communications 2 0 network.
Further details and advantages of the invention will be explained in what follows by means of two exemplary embodiments. The invention will be explained in greater detail in what follows by means of the exemplary embodiments represented in the drawings.
2 5 Shown are here in:
Fig. 1, a first exemplary embodiment of a data communications network in accordance with the invention, 3 o Fig. 2, a second exemplary embodiment of a data communications network in accordance with the invention, Fig. 3, a diagram indicating the maximum track distances as a function of the cloud tops and the flight level of the aircraft.
-.6.-Equal or functionally equal elements are provided with the same reference numerals in all drawing figures.
Fig. 1 represents a first data communications system in accordance with the invention, which is built up by means of aircraft. Two aircraft flying at high altitude are identified by 11, 12 in Fig. 1. Optical receiver stations 21, 22 have been installed in each aircraft 11, 12. The transceiver stations 21, 22 are directly coupled with each other by means of an optical data link 31. Furthermore, a base station 61, which is arranged on the surface 51 of the earth, is provided which, in the present case, is connected via a 1 o further data link 71 with an aircraft 11.
An interruption-free optical data link 31 is essential for this coupling of the transceiver stations 21, 22. For this reason, the two aircraft 11, 12 and the data link 31 connecting them, have been arranged above the cloud tops in the present example. Here, the flight level of the aircraft was identified as d3, the distance of the aircraft from each other as d1, and the cloud tops as d2.
The transceiver stations 21, 22 can be designed for bidirectional or unidirectional data transfer, i.e. for transmitting and/or receiving optically modulated data, wherein the 2 0 data to be transmitted are modulated in the form of a broadband laser beam. The optical transmitting unit of a transceiver station 21, 22 designed for transmitting contains means for the optical transmission of the data, a laser unit and an optical output amplifier. As a rule, an optical receiving unit of a transceiver station 21, 22 designed for receiving has a reception amplifier and means for optical data transfer. Furthermore, the transceiver stations 21, 22 have means for position stabilization, as well as means for tracking the optical beam. By means of this it is possible to assure that an interruption-free data link 31 is assured in case of slight vibrations, or respectively relative movements of the transceiver stations 21, 22 in respect to each other. The optical transmitting and receiving devices of a transceiver station 21, 22 are advantageously arranged so they are 3 0 freely pivotable in space, so that they can build up interruption-free data links with other, also freely movable transceiver stations 21, 22.
_ 7 _ The structure and functioning of such transceiver stations is exactly described in EP 0 847 150 A1 and EP 0 863 627 A1.
The functioning of the data communications network from Fig. 1 will be briefly described in what follows.
The first aircraft 11 in the example shown is located above a partial area 52 of the surface of the earth, while the second aircraft 12 is located above an area far distant from the partial area 52. The partial area 52 can be, for example, a crisis or war zone, above which the first aircraft 11 flies for the purpose of aerial reconnaissance. The data obtained from this aerial reconnaissance are l0 transmitted from the first transceiver station 21 to the second transceiver station 22 in the second aircraft 12 via a broadband data-modulated laser beam. It is advantageously possible to transmit data at transmission rates far above 100 Mbic/sec by means of this broadband laser beam. The data-modulated laser beams have a minimal angle of divergence and prevent therefore an undesired radiation. It is possible to assure by means of this type of data transmission that an interception-secure and interference-secure data transmission takes place at least above the partial area 52.
The demodulated data can be transmitted from the second aircraft 12 via a further 20 data link 71 to the station 61 on or near the ground. The data transmission via the second data link 71 can take place by means of radio signals, since in the case shown the ground station is located far outside the partial area 52, so that here a reduced requirement for interFerence, or respectively interception security of the data transmission results. However, an optical data transmission between the aircraft 12 and the station 61 on or near the ground would be conceivable.
Fig. 2 shows a second exemplary embodiment of a data communications network in accordance with the invention. Here, three aircraft 11, 12, 13 are provided, whose transceiver stations (not represented in Fig. 2) are respectively connected with each other via data links 31, 32. Two ground stations (or stations near the ground) 61, 62 are additionally represented, which are respectively connected with one of the aircraft 11, 12 via further data links 71, 72. A closed data communications network can therefore be -.8.-created in the example represented in Fig. 2, wherein a completely interception-secure and interference-secure data transmission between two ground stations 61, 62 is possible over very large distances.
Figs. 1 and 2 show that it is possible to create any arbitrary data communications networks in accordance with the invention in that any arbitrary number of aircraft 11, 12, 13 and ground stations 61, 62 are suitably connected by means of laser-optical data links. As already mentioned, an interruption-free optical data link 31, 32 is essential for the functioning of the data communications network. An optical link which is interruption-l0 free over great distances, can typically, but not necessarily, be assured above the cloud tops 41. For this reason the aircraft 11, 12, 13 connected with each other via data links 31, 32 must fly at least high enough that the respective data links 31, 32 between them are dependably arranged above the cloud tops 41 (d4 > d2).
Fig. 3 shows a diagram indicating the maximum track distances (d1 ) between two aircraft as a function of the flight level (d3) and the cloud tops (d2). It turns out that, with assumed cloud tops at 12 km and a flight level of 16 km, a maximum distance of approximately 500 km results between the two aircraft, while at a flight level of 30 km the free distance nearly doubles.
To create the data communications network in accordance with the invention, aircraft 11, 12, 13 were used in Figs. 1 and 2, which are designed for flying at great altitude.
Such high- altitude aircraft, which as a rule are jet-propelled, have a service ceiling which mostly lies high above the maximum cloud tops. However, in every case the aircraft 2 5 should have a ceiling of more than 12,000 m. It would also be conceivable to use captive balloons in place of aircraft. Very great altitudes, as far as up into the stratosphere, can be attained by means of captive balloons.
However, these aircrafts can also be designed as so-called unmanned drones, such 3 o as are often employed for reconnaissance purposes in crisis zones.
Claims (8)
1. A wireless data communications system - with a plurality of flying objects (11, 12, 13) capable of changing their position, - said flying objects being located in a common, limited area of the earth's atmosphere, or at the distance of the earth atmosphere from the surface (51) of the earth, - with at least one optical transceiver station (21,22) in each flying object (11, 12,13), each of which can be connected interference-free by means of first wireless data links (31,32) which are designed at least partially as laser-optical data links using a broadband laser beam, having a minimal angle of divergence to assure an interception-secure and interference-secure data, - with at least one fixed station (61,62) on or near the ground, which can be connected with at least one transceiver station (21, 22) via second wireless connections (71,72) wherein at least one of the transceiver stations (21,22) is designed for bi-directional data transfer and has an optical receiving unit and an optical transmitting unit for this purpose, the optical transmitting unit containing means for optical data modulation, a laser unit and an optical output amplifier for transmitting data-modulated laser signals and the optical receiving unit having a reception amplifier and means for optical data modulation, the transceiver stations having means for position stabilization and means for tracking the optical beam, and at least one of the transceiver stations (21, 22) is seated freely pivotable in space in such a way that this transceiver station (21, 22) can be coupled via first data links (31, 32) with any arbitrary transceiver station (21, 22).
2. The wireless data communications network in accordance with claim 1, characterized in that the means for position stabilization and/or means for tracking the optical beam assure an interruption-free optical data connection (31, 32) in case of slight vibrations and/or relative movements between the transceiver stations (21, 22).
3. The wireless data communications network in accordance with claim 1, characterized in that the data transmission rate of the broadband laser beam is at least several, preferably 25 Mbit/sec.
4. The wireless data communications network in accordance with one of the preceding claims 1 to 3, characterized in that the flying objects (11, 12, 13) are high-altitude aircrafts with a maximum flight level of at least 10,000 m.
5. The wireless data communications network in accordance with one of the preceding claims 1 to 3, characterized in that said two flying objects (11, 12, 13), which are optically coupled with each other by means of a data transfer, are essentially at the same flight level, and that the first data link (31, 32) between these two flying objects (11, 12, 13) is arranged in relation to the ground respectively above the cloud tops (41).
6. A method for operating a data communications network in accordance with one of the preceding claims 1 to 5, having the following method steps:
(a) a data transfer is performed between at least two transceiver stations (21, 22), each provided in flying objects (11, 12, 13), via the first data links (31, 32), wherein an optical laser signal is used at least in sections for the data transfer, (b) then a wireless data transfer between at least one transceiver station (21, 22) and a station (61, 62) on or near the ground takes place via the second data links (71, 72), wherein a data signal is received from the respective transceiver station (21, 22) and/or is transmitted to the respective transceiver station (21, 22) wherein the data transfer in method step (b) takes place by means of the data-modulated laser signals.
(a) a data transfer is performed between at least two transceiver stations (21, 22), each provided in flying objects (11, 12, 13), via the first data links (31, 32), wherein an optical laser signal is used at least in sections for the data transfer, (b) then a wireless data transfer between at least one transceiver station (21, 22) and a station (61, 62) on or near the ground takes place via the second data links (71, 72), wherein a data signal is received from the respective transceiver station (21, 22) and/or is transmitted to the respective transceiver station (21, 22) wherein the data transfer in method step (b) takes place by means of the data-modulated laser signals.
7. The data transmission method in accordance with claim 6, characterized in that the data transfer in method step (b) takes place by means of radio link signals.
8. The data transmission method in accordance with claim 6 or 7, characterized in that in method step (a) additional flying objects (11, 12, 13) are employed for data transmission when needed.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH104199 | 1999-06-03 | ||
| CH199901041/99 | 1999-06-03 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2307382A1 CA2307382A1 (en) | 2000-12-03 |
| CA2307382C true CA2307382C (en) | 2005-07-12 |
Family
ID=4201089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002307382A Expired - Fee Related CA2307382C (en) | 1999-06-03 | 2000-05-01 | Wireless data communications network and method for operating the data communications network |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP1058409B1 (en) |
| JP (1) | JP2001016155A (en) |
| AT (1) | ATE409989T1 (en) |
| CA (1) | CA2307382C (en) |
| DE (1) | DE50015375D1 (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6751442B1 (en) | 1997-09-17 | 2004-06-15 | Aerosat Corp. | Low-height, low-cost, high-gain antenna and system for mobile platforms |
| EP1017188A3 (en) * | 1998-12-30 | 2001-12-12 | Lucent Technologies Inc. | Method and system for high speed data access from remote locations |
| WO2002087112A2 (en) * | 2001-04-18 | 2002-10-31 | Space Data Corporation | Unmanned lighter-than-air safe termination and recovery methods |
| US7356390B2 (en) | 1999-06-29 | 2008-04-08 | Space Data Corporation | Systems and applications of lighter-than-air (LTA) platforms |
| WO2001059961A1 (en) * | 2000-02-08 | 2001-08-16 | Sky Station International, Inc. | High altitude optical telecommunications system and method |
| US7251223B1 (en) | 2000-09-27 | 2007-07-31 | Aerosat Corporation | Low-height, low-cost, high-gain antenna and system for mobile platforms |
| SG138465A1 (en) * | 2000-09-27 | 2008-01-28 | Aerosat Corp | Low-height, low-cost, high-gain antenna and system for mobile platforms |
| US9643706B2 (en) | 2001-04-18 | 2017-05-09 | Space Data Corporation | Systems and applications of lighter-than-air (LTA) platforms |
| US9908608B2 (en) | 2001-04-18 | 2018-03-06 | Space Data Corporation | Systems and applications of lighter-than-air (LTA) platforms |
| US9632503B2 (en) | 2001-04-18 | 2017-04-25 | Space Data Corporation | Systems and applications of lighter-than-air (LTA) platforms |
| US8504019B2 (en) | 2007-03-30 | 2013-08-06 | Livetv, Llc | Aircraft communications system with data memory cache and associated methods |
| EP2879312A1 (en) * | 2013-11-29 | 2015-06-03 | EADS Construcciones Aeronauticas S.A. | A communication system for managing a flying operation involving two or more aircraft |
| US9780865B2 (en) | 2014-01-27 | 2017-10-03 | The Boeing Company | Aircraft-noded data communication network |
| US10181895B2 (en) | 2014-09-04 | 2019-01-15 | Honeywell International Inc. | Free space laser and millimetre wave(MMW) network for airborne relay networks |
| BR112017013836B1 (en) | 2014-12-24 | 2022-05-24 | Space Data Corporation | Detachment of a platform by pending collision |
| US10403160B2 (en) | 2014-12-24 | 2019-09-03 | Space Data Corporation | Techniques for intelligent balloon/airship launch and recovery window location |
| US10059421B2 (en) | 2014-12-30 | 2018-08-28 | Space Data Corporation | Multifunctional balloon membrane |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3742358A (en) * | 1970-12-30 | 1973-06-26 | R Cesaro | Tethered airborne communications and information transfer system |
| GB2082995B (en) * | 1980-08-27 | 1984-02-08 | Mcnulty John Anthony | Airborne relay station |
| JP3077190B2 (en) * | 1990-10-30 | 2000-08-14 | ソニー株式会社 | Optical space transmission equipment |
| JPH0527002A (en) * | 1991-02-06 | 1993-02-05 | Jiesu:Kk | Tracking mechanism used in optical communication |
| AU5423096A (en) * | 1996-03-15 | 1997-10-01 | Alfred Y. Wong | High-altitude lighter-than-air stationary platforms including ion engines |
| JPH1065620A (en) * | 1996-08-14 | 1998-03-06 | Nec Corp | Data optical communication system |
| US6018659A (en) * | 1996-10-17 | 2000-01-25 | The Boeing Company | Airborne broadband communication network |
| EP0863627B1 (en) * | 1997-03-07 | 2001-09-19 | Contraves Space AG | Method and means for optical data transmission via satellites |
| JPH114196A (en) * | 1997-06-11 | 1999-01-06 | Toshiba Corp | Optical communication system and optical transmitter therefor |
-
2000
- 2000-04-12 DE DE50015375T patent/DE50015375D1/en not_active Expired - Lifetime
- 2000-04-12 EP EP00107837A patent/EP1058409B1/en not_active Expired - Lifetime
- 2000-04-12 AT AT00107837T patent/ATE409989T1/en not_active IP Right Cessation
- 2000-05-01 CA CA002307382A patent/CA2307382C/en not_active Expired - Fee Related
- 2000-06-02 JP JP2000165862A patent/JP2001016155A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| ATE409989T1 (en) | 2008-10-15 |
| DE50015375D1 (en) | 2008-11-13 |
| EP1058409B1 (en) | 2008-10-01 |
| JP2001016155A (en) | 2001-01-19 |
| EP1058409A1 (en) | 2000-12-06 |
| CA2307382A1 (en) | 2000-12-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2307382C (en) | Wireless data communications network and method for operating the data communications network | |
| Alfattani et al. | Aerial platforms with reconfigurable smart surfaces for 5G and beyond | |
| US10084528B2 (en) | Concurrent communications via wavefront multiplexing and aerial vehicles | |
| RU2735236C2 (en) | Satellite communication system | |
| US6285878B1 (en) | Broadband wireless communication systems provided by commercial airlines | |
| CN107070532B (en) | System for providing high speed communication service in airborne wireless cellular network | |
| JP4420198B2 (en) | Method, system and apparatus for using binary search pattern to identify interfering mobile terminals | |
| US7379673B2 (en) | Mobile communications system | |
| US5722042A (en) | Satellite communication system having double-layered earth orbit satellite constellation with two different altitudes | |
| Pinkney et al. | Unmanned aerial vehicle (UAV) communications relay | |
| CN109347492B (en) | System and method for enhancing space-to-air coverage capability of mobile communication base station | |
| CN107689828B (en) | Method for recovering communication transmission function in aircraft by unmanned aerial vehicle | |
| KR101846227B1 (en) | Antenna tracking method between pilotless aircraft in realy link of datalink for video information using datalink for operation control | |
| US10212610B2 (en) | System for telecommunications by network of stationary high-altitude platforms and drifting balloons | |
| US20130044677A1 (en) | Telecommunications System Comprising an Airborne Communication Node, Airborne Communication Node and Tactical Radio Node | |
| US6205320B1 (en) | System for satellite to airship to gateway/customer premise equipment, and airship to airship, high data rate relay | |
| CN112866971A (en) | Satellite fusion unmanned aerial vehicle carries on aerial to ground networking system of 4G communication base station | |
| Casey | Free space optical communication in the military environment | |
| US7535419B2 (en) | Method for data exchange between military aircraft and device for carrying out this method | |
| CN109039433A (en) | A kind of installed load system of high throughput satellite | |
| WO2001059961A9 (en) | High altitude optical telecommunications system and method | |
| EP3851931B1 (en) | Drone network and method of operating | |
| Leitgeb et al. | Hybrid wireless networks for civil-military-cooperation (CIMIC) and disaster management | |
| Ravishankar et al. | Free space optics and radio frequency signals in spacial communication | |
| RU2817401C1 (en) | Aerial object radio communication system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |