HYBRID COMMUNICATION

Abstract

Apparatus for providing communication between ground-based User Equipment (UE) and at least one core network and a method for providing wireless communication between ground-based User Equipment (UE) and at least one core network are disclosed. The apparatus for providing communication between ground-based User Equipment (UE) and at least one core network comprises a plurality of low earth orbit satellites each comprising at least one satellite-based optical transmitter element and at least one satellite-based optical receiver element for providing at least one optical communication link; and at least one aerial vehicle comprising at least one aerial vehicle based optical transmitter element and at least one aerial vehicle based optical receiver element for providing at least one optical communication link and at least one directional antenna for providing a wireless communication link to a ground-based station and/or mobile UE.

Claims

1. An apparatus for providing communication between ground-based User Equipment (UE) and at least one core network, comprising: a plurality of low earth orbit satellites each comprising at least one satellite-based optical transmitter element and at least one satellite-based optical receiver element for providing at least one optical communication link; and at least one aerial vehicle comprising at least one aerial vehicle based optical transmitter element and at least one aerial vehicle based optical receiver element for providing at least one optical communication link and at least one directional antenna for providing a wireless communication link to a ground-based station and/or mobile UE.

2. The apparatus as claimed in claim 1 further comprising: the plurality of low earth orbit satellites each comprise at least one satellite-based optical transceiver element comprising the at least one satellite-based optical transmitter element and the at least one satellite-based optical receiver element.

3. The apparatus as claimed in claim 1, further comprising: the at least one aerial vehicle comprises at least one aerial vehicle based optical transceiver element comprising the at least one aerial vehicle based optical transmitter element and the at least one aerial vehicle based optical receiver element.

4. The apparatus as claimed in claim 1, further comprising: each aerial vehicle comprises at least one optical phased array.

5. The apparatus as claimed in claim 1, further comprising: each aerial vehicle comprises at least one aerial vehicle based optical terminal that each comprise the at least one aerial vehicle based optical transmitter element and the at least one aerial vehicle based optical receiver element.

6. (canceled)

7. The apparatus as claimed in claim 5, further comprising: the at least one aerial vehicle based optical terminal comprises at least one aerial vehicle based optical phased array.

8. The apparatus as claimed in claim 1, further comprising: each low earth orbit satellite comprises at least one satellite-based optical terminal that each comprise the at least one satellite-based optical transmitter element and the at least one satellite-based optical receiver element or at least one satellite-based optical transceiver element.

9. The apparatus as claimed in claim 7, further comprising: the at least one satellite-based optical terminal comprises at least one optical phased array.

10. The apparatus as claimed in claim 1, further comprising: at least one aerial vehicle comprises an aerial vehicle based gimble steering member that connects the at least one aerial vehicle based optical transmitter and the at least one aerial vehicle based optical receiver to the aerial vehicle.

11. The apparatus as claimed in claim 1, further comprising: at least one low earth orbit satellite comprises a satellite-based gimble steering member that connects the at least one satellite-based optical transmitter and the at least one satellite-based optical receiver to the low earth orbit satellite.

12. (canceled)

13. The apparatus as claimed in claim 1, further comprising: each optical communication link comprises a Wavelength Division Multiplexed (WDM) point-to-point bi-directional free space optical link.

14. The apparatus as claimed in claim 1 wherein: the plurality of low earth orbit satellites comprises a dynamic toroidal mesh of satellites.

15. The apparatus as claimed in claim 13, further comprising: the toroidal mesh of satellites comprises at least four inter-satellite links.

16. The apparatus as claimed in claim 1, further comprising: the at least one aerial vehicle comprises a pseudo static reconfigurable honeycomb mesh network of a plurality of High Altitude Platforms (HAPs).

17. The apparatus as claimed in claim 15, further comprising: the plurality of HAPs includes at least one hub HAP and a plurality of non-hub HAPs; and each hub HAP is arranged for collecting and routing data from the plurality of non-hub HAPs.

18. (canceled)

19. The apparatus as claimed in claim 1, further comprising: each aerial vehicle is arranged to communicate with a plurality of user equipment and/or at least one core network via a simple star topology.

20. The apparatus as claimed in claim 1, further comprising: at least one aerial vehicle is located near orbital plane crossing positions for adjacent satellite orbit planes.

21. The apparatus as claimed in claim 19, further comprising: each aerial vehicle is arranged to relay inter-plane Intersatellite Links (ISLs).

22. The apparatus as claimed in claim 20, further comprising: each aerial vehicle is arranged to relay inter-plane Intersatellite Links (ISLs) at high latitude.

23. A method for providing wireless communication between ground-based User Equipment (UE) and at least one core network, comprising the steps of: providing a wireless communication link between at least one ground-based UE and a first aerial vehicle of a plurality of aerial vehicles; providing an optical communication link between the first aerial vehicle and a first satellite of a plurality of satellites; providing at least a first inter-satellite optical communication link between the first satellite and a further satellite of the plurality of satellites; providing a still further optical communication link between the further satellite and a further aerial vehicle of the plurality of aerial vehicles; and providing a final wireless communication link from a final aerial vehicle that comprises the further aerial vehicle or a still further aerial vehicle of the plurality of aerial vehicles, to at least one UE or to a ground-based station in communication with a core network.

24.-26. (canceled)

Description

[0068] Embodiments of the present invention will now be described hereinafter, by way of example only, with reference to the accompanying drawings in which:

[0069] FIG. 1 illustrates a network of satellites and HAPs providing wide area communications between one or more core networks which may be distributed globally and ground-based User Equipment;

[0070] FIG. 2 illustrates an example of a steerable optical communications terminal comprising optical phased array transmit apertures and a focusing receive aperture mounted on a common gimble support mechanism;

[0071] FIG. 3 illustrates a communication network linking ground-based User Equipment and a core network via HAPs and Satellites and identifying components that can be utilised for the network in each layer of the network;

[0072] FIG. 4a illustrates communication links between low earth orbit satellites and a Hub HAP in connection with a honeycomb mesh network of HAPs;

[0073] FIG. 4b illustrates a honeycomb mesh network of HAPs;

[0074] FIG. 4c illustrates a star arrangement of UEs, gateways or other cellular network equipment around a central Hub HAP;

[0075] FIG. 4d illustrates RF cells covered by a single HAP payload linking to ground based equipment in a star topology;

[0076] FIG. 5 illustrates a 2D projection of satellites organised into a toroidal mesh network, wherein satellites are linked within and across orbital planes; and

[0077] FIG. 6 illustrates orbits of satellites around the earth as viewed from above the poles wherein loss of communication links at orbital crossover points are supported by HAPs.

[0078] In the drawings like reference numbers refer to like parts.

[0079] FIG. 1 illustrates a communication network 100 including satellites 105 (four shown in FIG. 1) and HAPs 110 for establishing wide area communication links between at least one core network 115 and ground-based users of User Equipment (UE) 120. The wide area communication links can be worldwide communication links or links between nodes distributed across single continents or across single countries or states. In the example embodiment, a communication path exists between the core network 115 and at least one ground-based UE 120. Ground-based stations 125 in connection with the at least one core network 115 provide mm-Wave communication links 130 or other such wireless links to at least one HAP 110. The at least one HAP 110 may comprise optical communication equipment for communicating with at least one satellite 105 via at least one optical communication link 135. Optionally, the at least one optical communication link 135 may be a point-to-point free space optical communication link.

[0080] Each satellite 105 (four shown in FIG. 1) may communicate with at least one further satellite 105 via at least one optical communication link 140. The at least one further satellite may communicate with at least one Hub HAP 150 via at least one optical communication link 155. The at least one Hub HAP 150 may communicate with at least one further HAP 110 via at least one inter-HAP optical communication link 160.

[0081] The at least one HAP 110 may provide at least one wireless communication link 165 to the at least one ground-based UE 120 within a coverage area 170. The at least one wireless communication link 165 may be a cellular communication link or mm-Wave communication link.

[0082] FIG. 2 illustrates an example embodiment of a gimble mounted optical terminal 200 comprising at least one optical phased array. The gimble mounted optical phased array may be mounted to an aerial vehicle and/or a satellite. Optionally, multiple optical terminals may be mounted to each HAP and/or satellite. Optionally, the optical terminal may be mounted to an aerial vehicle or satellite without a gimble 210. The optical terminal 200 may comprise at least one optical transceiver. Optionally, at least one optical transceiver may be mounted to each HAP and/or satellite.

[0083] In the example embodiment described with respect to FIG. 2, the terminal 200 that includes the optical phased array 200 includes a single central receiving aperture 230, and multiple (eighteen shown in FIG. 2) optical phased arrays with single and/or multiple wavelength transmitting apertures 220. Other numbers and positions for the receiving aperture/s and/or transmitting apertures could of course be used. Optionally, the optical terminal 200 may comprise an array of one or more types of aperture, wherein the types of aperture may comprise receiving apertures 230 and/or single and/or multiple wavelength transmitting apertures 220.

[0084] In an alternative embodiment, at least one optical phased array may be mounted to at least one satellite and/or at least one HAP. Optionally, the at least one phased array may be mounted on a gimble member and mounted to at least one satellite and/or at least one HAP. Optionally, the at least one optical phased array may be mounted to at least one satellite and/or at least one HAP with at least one separate receiver. Optionally, the at least one optical phased array may be mounted to at least one satellite and/or at least one HAP with a separate optical transceiver.

[0085] The example optical phased array may enable opto-electronic beam steering. Optionally, steering of the optical phased array may be controlled using 2D focal plane array detectors fed by the receiving aperture 230 and centroiding techniques to obtain sub pixel measurements of the relative angular alignment between two terminals/transceivers. Motion of HAPs may be static relative to motion of satellites. Centroiding techniques may comprise measuring angular coordinates of a target optical terminal and determining a pointing vector which may include an appropriate point ahead angle to correctly steer optical beams, thereby achieving closed loop control of optical terminal co-alignment. Opto-electronic beam steering precision may be on the order of micro radians (wad). Steering of the optical terminal 200, and therefore the at least one optical phased array, may comprise wide-angle steering using the gimble support 210. Optionally, steering of the optical phased array may be controlled using the optical receiver 230 and centroiding techniques.

[0086] A block diagram shown in FIG. 3 illustrates an example embodiment of a communication network 300 comprising HAPs and satellites. The network comprises three effective layers: a ground layer 301 shown at the bottom of FIG. 3; a HAP layer 302; and a space layer 303.

[0087] The ground layer 301 defines terrestrial elements of the network and comprises ground-based UEs 120; a core network 115 (not shown) in connection with at least one ground-based station, further comprising at least one ground-based base station 310 and/or at least one wide bandwidth gateway 315; and/or at least one optical ground station (GSN) 318. The optical GSN 318 may be in connection with at least one core network via ground based fibre links. Optionally, the at least one ground-based base station 310 may comprise at least one eNodeB and/or at least one core network gateway 115. Optionally, terrestrial elements of the network may already exist and certain embodiments of the present invention can thus be “retrofitted” to extant networks.

[0088] The HAP layer 302 defines aerial, such as stratospheric, domain elements of the network and comprises at least one HAP node 320 associated with a respective HAP 110 which may be in connection with at least one further HAP. Optionally, the HAP node 320 may be in connection with a honeycomb mesh network 325 of HAPs 110. Optionally, other types of network topology may be used for the network of HAPs. Inter-HAP connections 160 may comprise optical free space or RF communication links.

[0089] The HAP node 320 comprises a payload 330 comprising RF (or other such wireless) communication equipment for providing at least one communication link 165 to at least one ground-based UE 120 and/or at least one communication link 345 to at least one mm-Wave gateway 315. The wireless communication link 165 between HAP and UE may comprise RF and/or mm-Wave communication links. Payload 330 may further comprise at least one directional antenna.

[0090] The HAP node 320 may further comprise at least one base station 327 in connection with wireless communication equipment of payload 330. Optionally, the HAP node 320 may further comprise a router 350 for managing incoming and outgoing communication signals from the various types of communication links. The HAP node 320 may comprise an optical terminal 355 that may comprise laser base band equipment and at least one optical phased array. Weather permitting, at least one HAP node 320 may also form direct free space optical communication links with the at least one optical ground stations (GSN) 318. Optionally, the optical terminal 355 may further comprise an optical receiver. Alternatively, the optical receiver may be provided separate to the optical terminal 355. The example optical terminal may implement wavelength division multiplexing (WDM). An optical phased array may enable WDM using multiple co-aligned single wavelength transmitting apertures. An optical phased array (OPA) may enable WDM by transmitting multiple wavelengths of light through a single optical phased array. WDM may be implemented using a combination of multiple OPA apertures and/or multiple wavelengths from single aperture. Components of a HAP node 320 may be interconnected by fibre, and/or wired and/or wireless links.

[0091] A space layer 303 may comprise at least one satellite node 365 provided by a respective satellite 105 that may comprise at least one satellite-HAP optical terminal 370 for providing bi-directional satellite-HAP optical communication links 135 and one optical terminal 372 for providing bi-directional inter-satellite optical communication links 140 and a router 375. Optionally, one optical terminal may be provided for both satellite-HAP and inter-satellite bidirectional optical communication links. Optionally, the satellite node 365 may establish inter-satellite communication links 140 with at least one further satellite, wherein inter-satellite communication links may comprise optical communication links. Optionally, inter-satellite communications between further satellites may form a network 380 of satellites 105. An example satellite network structure may comprise a toroidal mesh network. Optionally, further HAP nodes of the satellite network 380 may establish optical communication links with further HAP nodes in a honeycomb mesh network or other network topology 325.

[0092] At least one of the optical terminals 370, 372 of the satellite node 365 may comprise laser base band equipment and at least one optical phased array. The satellite-satellite optical terminal 372 may establish a plurality of bi-directional inter-satellite communication links 140. The satellite-HAP optical terminal 370 may establish at least one and optionally a plurality of bi-directional optical communication links 135 with at least one HAP node 320. The router 375 of a satellite node may be used to switch data via an optimal route through the network. Optionally, a method of routing connections may comprise using Dijkstra shortest-path algorithms applied to the whole ground, air and space-based network or the like.

[0093] FIG. 4a, illustrates satellites 105 (three shown in FIG. 4a) in connection with a HAP node 320. At least one satellite 105 may communicate with a further satellite 105 via at least one inter-satellite communication link (ISL) 140 and/or at least one HAP node 320 via at least one optical communication link 135. Optionally, a HAP node 320 may act as a Hub HAP 400. The at least one Hub HAP node 400 may communicate with a network of HAPs that form part of a network 325. The Hub HAP 400 may communicate with multiple satellite nodes 105 simultaneously. Inter-HAP connections of the HAP network may comprise at least one optical communication link. Optionally, the HAP network may be reconfigurable.

[0094] An illustration of an example HAP honeycomb mesh network 325, as viewed from above, is shown in FIG. 4b. Optionally, a HAP network may form alternative structures. The HAP honeycomb mesh network 325 comprises at least one HAP 110 interconnected with at least one further HAP 110 by at least one communication link 160. Optionally, the at least one communication link 160 may comprise at least one optical communication link. Optionally, at least one HAP 110 of the honeycomb mesh network 325 is a Hub HAP 400.

[0095] FIG. 4c illustrates a star topology of the interconnect formed by a single HAP 410 and various ground-based UE and core networks via RF wireless links from at least one directional antenna mounted on the HAP 410. The at least one HAP illustrated in FIG. 4c may provide wireless communication to an overall service area 420, illustrated in FIG. 4d. The coverage area 420 associated with the service area may be divided into cells 450 (forty-eight shown in FIG. 4d). Optionally, the size and number of cells covered may vary according to user demands.

[0096] FIG. 5 illustrates a 2D projection of an example array 500 of satellites 105 arranged into orbital planes. The 2D projection shows at least one satellite 505 arranged into vertical loops representing orbital planes 510 and horizontal loops 520 (four shown) representing cross orbital plane links. Optionally, satellite planes and/or satellites may be added to and/or removed from an array as required. The array may form a constellation. Example satellite constellations may include a toroidal constellation or a Ballard rosette constellation or a Walker constellation or the like.

[0097] An example projection of satellite orbits 600 and HAPs 110 is illustrated in FIG. 6. The perspective illustrated in FIG. 6 is from above one of the poles of the Earth. At least one satellite may be organised into at least one orbital plane 605. In the example embodiment, at least one orbital plane cross point 610, in-plane inter-satellite communication links are maintained however cross-plane inter-satellite communication links are broken and remade. To overcome the adverse problems associated with breaking cross-plane inter-satellite communication links at least one HAP 110.sub.c may be provided near at least one orbital cross point 610 to relay at least one inter-satellite communication link during at least one orbital cross over period. Optionally, the at least one HAP 110.sub.c may further relay the at least one inter-satellite communication link for a period of time before and/or after the at least orbital crossover period. As the position of an orbital cross point changes with the earth's rotation, responsibility of relaying at least one inter-satellite communication link may shift from a first HAP 110.sub.c to at least one further HAP 110f because the Earth's rotation, and therefore HAP motion, is much greater than orbital precession of satellites. For example, as an orbital cross point 610 changes position and falls out of range of a HAP supporting/access area 615 into at least one further HAP supporting/access area 620, at least one inter-satellite communication link associated with the cross point can be relayed by at least one further HAP 110f in the further supporting area 620. The adjacent HAP supporting/access areas must have overlap to maintain the network links This method retains the fully connected topology of the satellite network.

[0098] Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to” and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0099] Features, integers, characteristics or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of the features and/or steps are mutually exclusive. The invention is not restricted to any details of any foregoing embodiments. The invention extends to any novel one, or novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0100] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.