Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W12/00—Security arrangements; Authentication; Protecting privacy or anonymity
  • H04W12/08—Access security
• • 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
  • H04B7/18506—Communications with or from aircraft, i.e. aeronautical mobile service
  • H04B7/18508—Communications with or from aircraft, i.e. aeronautical mobile service with satellite system used as relay, i.e. aeronautical mobile satellite service
• • 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
• • 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
  • H04B7/18506—Communications with or from aircraft, i.e. aeronautical mobile service
• • 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
  • H04B7/1853—Satellite systems for providing telephony service to a mobile station, i.e. mobile satellite service
  • H04B7/18532—Arrangements for managing transmission, i.e. for transporting data or a signalling message
  • H04B7/18534—Arrangements for managing transmission, i.e. for transporting data or a signalling message for enhancing link reliablility, e.g. satellites diversity
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
  • H04W16/24—Cell structures
  • H04W16/28—Cell structures using beam steering
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
  • H04W16/24—Cell structures
  • H04W16/30—Special cell shapes, e.g. doughnuts or ring cells
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
  • H04W4/30—Services specially adapted for particular environments, situations or purposes
  • H04W4/40—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P]
  • H04W4/42—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P] for mass transport vehicles, e.g. buses, trains or aircraft
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/12—Supports; Mounting means
  • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
  • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
  • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
  • H01Q1/246—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for base stations
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
  • H04L69/18—Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
  • H04W4/02—Services making use of location information
  • H04W4/021—Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
  • H04W4/30—Services specially adapted for particular environments, situations or purposes
  • H04W4/40—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P]
  • H04W4/46—Services specially adapted for particular environments, situations or purposes for vehicles, e.g. vehicle-to-pedestrians [V2P] for vehicle-to-vehicle communication [V2V]

Definitions

• the invention relates to the field of wireless communications, and more particularly to systems, methods and components for operation of cellular telephone networks in connection with unmanned and remotely piloted aerial vehicles.
• Wireless systems for general public communications used today are often "cell" based, as illustrated in the diagram of Figure 1.
• mobile phones or mobile devices (100) within a larger geographic region (101) are served by a distribution of fixed location local radio transceivers which provide two way wireless communications to the devices in sub-regions of the larger region (102).
• the mobile phone or mobile device moves from one location to a new location (103), it may be served by a different local fixed radio transceiver in the cellular wireless system (104), or by a different sector (104a, 104b, 104c) within the range of the same local fixed radio transceiver.
• the antenna radiation patterns of the fixed radio transceivers in the wireless system typically are oriented to be directionally along ground, as opposed to omnidirectionally or skyward. Some reasons for such limited radiation patterns include firstly that users of wireless devices in such system are limited to being almost always physically along the surface of the earth, as wireless cell phone and smartphone communications whilst in a commercial airplane are generally forbidden by law, and secondly that cellular based communications systems avoid interference between cells which repeat use of frequencies, by limiting the radiated power that may enter adjacent or nearby cells, which is effectuated at least in part by controlling of the radiation pattern which emanates from the antenna associated with the fixed radio transceiver.
• a simplified diagram of the radiation pattern of a typical fixed radio transceiver in a cellular-based wireless communications system appears in Figure 2. The horizontal or 'parallel to ground plane' pattern is indicated in (200) while the vertical pattern is indicated in (210).
• the fixed cellular radio transceiver antenna system (300) is typically mounted on a mast some distance above the ground (304) and designed to enable
• the beam is typically designed to subtend a useful angle of 5 to 10 degrees (302) and may as well be tilted towards the ground by an additional 5 to 10 degrees (305).
• So-called vertical side-lobes which point towards the ground in fact assist in supplying coverage to mobile devices nearer to the antenna (306a) whilst vertical side lobes that point skyward (306b) are of typically of no use or consequence, and are ignored as byproducts of the antenna system.
• FIG 4 there is shown a simplification diagram of the fixed radio transceiver antenna indicated in Figure 3, where each antenna (401, 402) is mounted up above the ground (410) and has a vertical radiation pattern substantially along ground (401a, 401b, 402a, 402b), and where the fixed radio transceivers are spaced according to some plan as might be in a typical cellular-type communications network in order to insure continuity of coverage.
• the actual spacing of the fixed radio transceivers is performed in 2 dimensions across the surface of a region to be covered, and a frequency re-use pattern is established such that the frequencies radiated from one fixed radio transceiver (401b) towards another (402a) are different, avoiding interference between adjacent locations. That is, the frequencies for communications associated with beam (401b) might be from frequency group /A, whereas those associated with beam (402a) might be from frequency group f % and so on.
• FIG. 4 The simplified situation depicted in Figure 4 has been replicated in two dimensions across populated areas in the world today such that there are large regions and even whole countries where there is essentially continuous coverage zone or layer (421) near the ground where under most open-air conditions, reliable communications can be conducted between a mobile device and the cellular system and then subsequent end points connected to the cellular system (such as the public switched telephone network, other mobile devices or computer systems exchanging datagrams with the mobile devices on the cellular network).
• Figure 5 is a so-called coverage map of the United States, where the blue regions are areas where there is continuous coverage of a cellular-type network capable of carrying either voice or datagram traffic to and from mobile devices located near the ground, and the white regions are areas where there is no coverage. As is evident by simple inspection, a majority of the United States is covered.
• UAVs unmanned aerial vehicles
• RPVs remotely piloted vehicles
• UAVs will be considered short range and low altitude aerial vehicles under 50 pounds in weight which fly under 2000 feet above ground level (AGL) and/or below legally controlled airspace, and may or may not have a remote operator actively guiding the UAV over part or all of a course of flight, where the remainder of the course of flight may be autonomously guided;
• RPVs will be considered long range and higher altitude longer range aerial vehicles above 50 pounds in weight, with typical normal-course flight altitudes above 2000 feet AGL and/or within legally controlled airspace, and always have a human remotely piloting and/or monitoring the vehicle, with allowances for automation of normal course flight such as the use of an autopilot as is customary in manned aerial vehicles.
• UAVs and RPVs were developed originally for primarily military reasons, and as such the communications with them principally made use of military line-of-sight communications methods for UAVs, and military satellite networks for RPVs.
• the present invention provides a system, method and components for managing and operating reliable communications with a wide variety of RPVs and UAVs.
• Embodiments of the system are configured to provide redundant coverage especially over populated areas where the operation of, and communications with, the RPV/UAV are especially important for safety reasons.
• the present invention is an improvement to the currently limited modern cellular data and voice network which is currently limited to near- ground operations..
• a cellular type communications system is provided.
• the system is configured to provide a first near-ground region to communicate with devices near the ground. Additional layers, such as, for example, one or more second layers are provided covering roughly the same areal extent as the first near- ground region but which are separated from each other, and which also are elevated above ground substantially.
• the system is configured to provide the second or additional elevated region or layer to serve as a region within which an aerial vehicle may rely on
• the cellular based network therefore handles near-ground communications through the first near-ground region, and skyward communications through the second or elevated region or regions.
• the levels preferably are separated from one another, which may be physically through the use of barriers, such as, for example, passive reflectors.
• the communications transceivers that is those of near-ground devices, and those of aerial vehicles, such as RPVs and UAVs, may be configured to operate using different protocols, so that in the event communications within the second region are attempted using a near-ground device, they will not affect the operation of the second level aerial region communications.
• a skyward communications protocol may be differentiated from the along- ground communications protocol in order to uniquely identify UAV and RPV transceivers from along-ground cell phones and smartphones and the like.
• the present system may be configured by deploying an antenna system mounted on an existing cellular network base station fixed transceiver antenna mount.
• the antenna system preferably is a skyward antenna system and is configured to radiate radio frequency energy skyward.
• the radiation frequency is propagated over some subtended angle in a cone or other shape.
• the antenna system may be connected to a second set of transceiver equipment similar or identical to existing cellular network equipment and effectuates communications with vehicles in the air (e.g., UAVs and RPVs) instead of along the ground.
• vehicles in the air e.g., UAVs and RPVs
• the skyward signal propagated by the skyward pointing antennas are polarized, and preferably, horizontally or circularly polarized.
• two sets of signals are radiated skyward of differing sets of frequencies, where the angles subtended by the radiation pattern differ in order to effectuate continuous communications coverage for differing elevation bands above the antenna.
• a first angle of a radiation pattern may extend skyward and represent a region of frequencies for which a first type of skyward vehicle is configured to communicate using. This may be for UAVs, which typically are operated at lower levels compared with some RPVs.
• a second frequency region may be provided through a second radiation pattern having a different subtended angle, which may provide a region for RPV communications.
• the differing elevation bands may represent second layers of the skyward region.
• the skyward signal propagated by the skyward pointing antennas may be polarized in accordance with preferred polarization.
• the upper radiation propagation from a skyward antenna may be configured to direct radiation in a pattern, such as, for example, in a shape, like a cone.
• Signal isolation may be implemented in connection with the embodiments of the system and communicating devices to enhance the quality of the communications, and thereby eliminate or reduce the potential for unintentional interaction between signals of differing frequencies, or bands of frequencies.
• Embodiments may provide isolation of the signals using diverse frequencies (e.g., certain frequencies for UAVs versus other frequencies for RPVs). In addition to frequency diversity, signals also may be isolated by polarization patterns.
• polarization may include right-hand circular polarization and left- hand circular polarization.
• one skyward cone e.g., a lower layer
• another skyward cone e.g., a higher level layer
• the system, method and devices may further provide polarization patterns for UAV and RPV transmitting and receiving, as well as the base station.
• polarization patterns may be implemented for transmission and reception between communicating components, such as transceivers.
• the skyward radiation energy preferably may be emitted as a pattern, and the skyward pointing radiation pattern, according to some preferred embodiments, is
• the skyward pointing radiation pattern may be electronically steered to follow a specific UAV or RPV.
• the energy radiated for a given skyward pattern may be limited to assist in providing separation between bands of aerial vehicle continuous communications regions.
• UAV and RPV transceivers may be configured to have unique or differentiated identification numbers or classes of IMEIs (international mobile equipment identity numbers) enabling rapid differentiation by the cellular communications network between RPV and UAV communications and along-ground communications.
• IMEIs international mobile equipment identity numbers
• the system may be configured to take any action thereupon, such as special routing of the datagrams or voice traffic.
• the systems may incorporate and include processing components, such as, for example, processors, microprocessors, and circuits and software with instructions for processing communications from communicating equipment and transceivers carried or associated therewith.
• the software may be stored on a suitable storage component, such as flash memory, hard disk storage, or other suitable media, and include instructions for carrying out the steps for implementing the communications over the first or near-ground zone level and second levels where aerial communications with aerial vehicles take place.
• FIG. 1 is a schematic illustration representing a "cell" based wireless system for general public communications used today.
• FIG. 2 is a diagram of a radiation pattern of a typical fixed radio transceiver in0 a cellular-based wireless communications system.
• FIG. 3 is a pictorial diagram illustrating a base station and antenna in a fixed transceiver antenna system showing a visualized representation of a vertical radiation pattern.
• Fig. 4 is a diagram showing a plurality of the fixed radio transceiver antenna of Figure 3, shown spaced apart from each other and illustrating respective radiation patterns.5
• Fig. 5 is a depiction of a coverage map of the United States, illustrating
• regions of coverage for a cellular-type network capable of carrying either voice or datagram traffic to and from mobile devices located near the ground.
• Fig. 6 is an illustration depicting an example of an unmanned aerial vehicle (UAV).
• UAV unmanned aerial vehicle
• FIG. 7 is an illustration depicting an example of a remote piloted vehicle
• FIG. 8 is a schematic diagram illustrating a typical UAV/RPV military communication network.
• Fig. 9 is an illustration depicting an example of a remote piloted vehicle5 (RPV) satellite communications antenna.
• RSV remote piloted vehicle5
• FIG. 10 is an illustration of a preferred embodiment depicting a system for communicating with UAVs and RPVs.
• This invention pertains to the use of some parts of the existing installed base of cellular networks presently serving most of the world's population along the ground, as the backbone of a system for servicing the communications and datagram exchange needs of emerging commercial UAV and RPV activities in the air.
• new antennas are mounted on one or more existing cellular network towers (1001, 1002) however pointing skyward instead of along-ground, and with either horizontal or right- or left-circularly polarized radiation patterns, and which nominally radiate upwards in a cone shape subtending some angle (1050), though any other shape is possible.
• the shape of the upward radiation pattern may be electronically steered or controlled. It may also be isolated further from ground radiation patterns by passive shield or screens (1060), further minimizing the effect of side- lobes from the ground-oriented radiation patterns on aerial transceivers, and vice versa.
• 1002c is created by designing both the shape of the radiation pattern in conjunction with the power of each transceiver (both those on the UAV/RPV as well as that associated with the fixed location transceiver) in any number of manners well known by those practiced in the art, including commercially available software.
• an overlap region can be easily designed which produces an elevated layer (1021) in which an aerial vehicle can be assured of having both no black-out regions (1080), as well as sufficient link margin to insure reliable communications.
• a second (or third or fourth, and so on) set of cones of skyward radiating patterns may be built, with different subtended angles (1051) and different polarizations and/or powers for each transceiver pair, such that another layer (1031) of continuous coverage over some larger region is created at a different elevation.
• an aerial vehicle could enter airspace where it was operating below a contiguous
• sets of skyward cones may have polarizations different polarizations of other sets of skyward cones.
• the polarization also may be configured to correspond with polarizations of receiving and transmitting transceivers of communicating components (e.g., UAVs and RPVs).
• one set of cones may be configured with right-hand circular polarization and another set of skyward cones may be configured with left-hand circular polarization.
• These configurations may provide increased isolation of the signals, in addition to any isolation provided by the frequency diversity (e.g., between cone sets).
• a first set of skyward signals may be polarized in a first polarization pattern and a second set of skyward signals may be polarized in a second polarization pattern.
• the polarization patterns may be circular patterns.
• one set of skyward signals may be polarized in a right-hand circular polarization pattern and another set, such as a second set, of skyward signals may be polarized in a left-hand circular polarization pattern.
• Each set of skyward signals may be configured to form a shape, such as, for example, a cone.
• the system may be configured to communicate where a first set of skyward signals forms a first skyward cone, and where a second set of skyward signals forms a second skyward cone.
• the first and second sets of signals preferably have different polarizations to further isolate the first set from other signal sets.
• the first skyward cone may be polarized in a right-hand circular polarization pattern
• the second skyward cone may be polarized in a left-hand circular polarization pattern.
• Skyward pointing antennas may be used to radiate sets of signals of differing frequencies, and where each signal set has a different frequency.
• the skyward radiation patterns preferably are electronically created.
• the unmanned aerial vehicle (UAV) or remote piloted vehicle (RPV) may be configured with a transceiver that communicates through a polarized signal pattern similar to the polarized signal pattern of communications from the network and radiated from the skyward pointing antennas having the communicating frequency.
• the skyward pointing radiation pattern may be electronically steered to follow a specific unmanned aerial vehicle (UAV) or remote piloted vehicle (RPV).
• UAV unmanned aerial vehicle
• RSV remote piloted vehicle
• one skyward signal cone may be an upper layer and another skyward cone may be a lower layer.
• Each of the layers preferably has a different polarization pattern.
• the first or upper skyward layer may have a left-hand circular polarization pattern of radiation and the second or lower skyward layer may have a right-hand circular polarization pattern of radiation.
• the radiation energy for each layer is configured to have different frequencies for each layer or cone.
• the RPV communication takes place within the first or upper layer (e.g., the first skyward cone), and the UAV communication takes place within the second or lower layer (e.g., second skyward cone).
• the UAV in this example has a transceiver configured for transmitting and receiving, and more particularly, the UAV transceiver is configured to transmit and receive signals in a right-hand circular polarization pattern.
• the RPV according to this example, has a transceiver configured for transmitting and receiving, and more particularly, the RPV transceiver is configured to transmit and receive signals in a left-hand circular polarization pattern.
• the cellular network base station preferably has a transceiver that is configured to transmit and receive signals in a polarization pattern (and frequently) that matches the pattern of the communicating transceiver (such as a transceiver of a UAV or RPV), which, according to some preferred embodiments, may be a right-hand circular polarization pattern or a left-hand circular polarization pattern.
• a transceiver that is configured to transmit and receive signals in a polarization pattern (and frequently) that matches the pattern of the communicating transceiver (such as a transceiver of a UAV or RPV), which, according to some preferred embodiments, may be a right-hand circular polarization pattern or a left-hand circular polarization pattern.
• the altitude and thickness of the continuous communications layers can be adjusted. This adjustment capability enables the continuous communication layer to follow either a certain elevation above ground level or a certain elevation above mean sea level.
• Aircraft altitudes are often controlled by measurement of altitude via barometric pressure and UAVs and RPVs may be directed by local air traffic controllers or regulations in a similar manner.
• the layer can be adjusted in elevation above ground level or mean sea level as often as desired, even minute- by-minute, according to any parameter necessary.
• the lower altitude continuous communications layer (1021) might be controlled to range from 500 feet above ground level to 2000 feet above ground level.
• the higher altitude continuous communications layer (1031) might be controlled to range from 20,000 feet above mean sea level to 25,000 feet above mean sea level.
• the receiver in the UAV (1051) is many times closer to the transmitter (1002) than the high altitude RPV (1050).
• the smaller UAV (1051) would have a lower gain receiving antenna compared to the larger RPV (1050) and thus the received signal power in the UAV (1051) from the radiated power in the higher altitude directed cone (1002d) can be less than that received by the UAV (1051) from the radiated power in the lower altitude directed cone (1002c).
• the available gain from a ground-pointing antenna which is able to be deployed in the RPV (1050) can more than make up for any signal loss from its extra distance, and therefore it is possible in many configurations for the higher altitude directed beam (1002d) emanating from the ground antenna (1002) to be considerably lower field strength at UAV (1051) than the field strength from the lower altitude directed beam (1002c) at UAV (1051).
• the frequency diversity indicated in Figure 10 only makes use of 4 frequency groups (/ ⁇ ,/ ⁇ ,/ ⁇ ,/ ⁇ ), it is easily recognized by those practiced in the art of cellular system design that many more arrangements are possible without departing from the scope of the invention.
• link margins between the fixed ground transceivers (1001, 1002) and UAVs (1051) and RPVS (1050) operating in communications layers (1021) and (1031) respectively can be more tightly constrained than the link margins between the fixed ground transceivers and typical personal mobile devices and smart phones transceiving via along-ground links (1001a, 1001b, 1002a, 1002b).
• customary cellular system protocols such as those employed in GSM, 3G, 4G or LTE signaling and link management protocols can include special identification of signals directed to or coming from UAVs or RPVs.
• Such an adjustment to the protocols can be as simple as a specialized IMEI class of numbers.
• Fig. 10 illustrates network towers 1001, 1002
• a plurality of network towers may be utilized in conjunction with the system, methods and components shown and described herein.
• the skyward pointing antennas may be connected to existing network equipment.
• the network equipment is configured to treat the skyward pointing antenna or antennas as an additional cell zone.
• the radiation shape or pattern according to some preferred embodiments is described as a cone, but may be configured to have other shapes.
• the skyward antennas may be configured to operate with an additional set of network equipment or component thereof.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Aviation & Aerospace Engineering (AREA)
• Physics & Mathematics (AREA)
• Astronomy & Astrophysics (AREA)
• General Physics & Mathematics (AREA)
• Computer Security & Cryptography (AREA)
• Mobile Radio Communication Systems (AREA)
• Variable-Direction Aerials And Aerial Arrays (AREA)
• Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)

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• 2016
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