Systems and methods for determining the orientation of an electronically steerable antenna - Patents.com

Abstract

Determining the set physical orientation of an electronically steerable satellite antenna using signals received at the satellite antenna is described. The set physical orientation of the satellite antenna may be static relative to the antenna. The antenna may then scan a beam through a range of angles to measure the signal strength of a signal from a transmitter (e.g., a satellite) to determine the signal's direction of incidence. The signal's direction of incidence from a corresponding known orbital position of the satellite allows the satellite antenna to determine the set physical orientation with high accuracy. In particular, the high accuracy allows avoidance angles to non-target satellites to be minimized, allowing for more efficient antenna operation with fewer interference mitigation operations.

Description

[Background technology]

[0001] A satellite communication system may include satellites in geosynchronous earth orbit (GEO) orbit to facilitate communications between user terminals on the Earth and the GEO satellites. GEO satellites have an orbital period equal to the rotation period of the Earth. Thus, GEO satellites may be geostationary or quasi-geostationary such that the GEO satellites generally appear to be stationary in the sky to the user terminal or circulating to a very limited extent. For geostationary GEO satellites, the orbit is directly above the Earth's equator. Thus, aiming a satellite antenna at a user terminal may be relatively simple since the aiming of the satellite antenna may be static without the need to re-aim or change the direction of the antenna. Furthermore, because the aiming of the satellite antenna is static, there is negligible interference to other satellites.

[0002] However, because geostationary GEO satellites are located above the equator, there is a limited number of "slots" or space availability available in geostationary orbit. In addition, because GEO satellites orbit the Earth at a relatively high altitude, long latencies are incurred for signals transmitted between the Earth and the GEO satellites. Such long latencies are particularly inconvenient in certain time-sensitive data contexts. As a result of the unavailability of geostationary orbit slots, the desire to provide a satellite communication system with reduced latency, and other constraints on GEO satellites, satellite communication systems may additionally or alternatively use low Earth orbit (LEO) or medium Earth orbit (MEO) satellites to facilitate communication with user terminals. LEO and MEO satellites and / or orbits may be collectively referred to herein as non-geosynchronous (non-GEO).

[0003] Because non-GEO satellites have orbital periods that are not equal to the rotation period of the Earth, the non-GEO satellites do not appear stationary in the sky relative to the user terminal. User terminals for communication with non-GEO satellites typically employ some form of tracking that allows a satellite antenna at the user terminal to target the non-GEO satellite as it passes through the sky relative to the user terminal by moving the satellite antenna and / or the beam of the satellite antenna. Although the tracking function increases the complexity of the user station, the ability to use non-GEO satellites for communication with the user terminal provides advantages that offset the additional complexity of the user terminal. However, there are disadvantages associated with the use of non-GEO satellites that would be desirable to mitigate. In particular, when using a satellite antenna at a user terminal to track a non-GEO satellite, it may be advantageous to avoid interference with other satellites present in the sky relative to the user terminal (e.g., in maintaining operational status or avoiding violations of licensing regimes). Summary of the Invention

[0004] The present disclosure relates to determining the orientation of an electronically steerable satellite antenna relative to the Earth to, for example, more accurately determine interference angles to non-target satellites to help more efficiently avoid interference to the non-target satellites. The present disclosure allows the orientation of the electronically steerable antenna to be analyzed with a high level of accuracy. Thus, the operation of a user terminal may experience improved performance through reduced interference mitigation operations. In particular, by accurately determining the orientation, the error range of the avoidance angles to non-target satellites may be reduced for the satellite antenna of the user terminal because the radiation pattern of the satellite antenna may be accurately modeled.

[0005] The present disclosure generally determines a set physical orientation of an electronically steerable satellite antenna based on triangulation using signals received from multiple transmitters (e.g., one or more satellites). By determining the direction of incidence of the signals received from the multiple transmitters, the antenna system may analyze the set physical orientation of the antenna. Because signal reception may be performed autonomously by the antenna system, the set physical orientation may be analyzed without user or technician intervention (e.g., without requiring a user to physically measure the orientation of the antenna).

[0006] In view of the above, the present disclosure facilitates determining a set physical orientation of an electronically steerable satellite antenna for use in a satellite communication system. The present disclosure includes determining a position of the electronically steerable satellite antenna relative to the Earth. A plurality of signals is received from at least two different respective satellites at known orbital positions relative to the Earth. For clarity, a plurality of signals may be received, each different one of which may be received from at least two different orbital positions relative to the antenna. Receiving the signals may include electronically steering the electronically steerable satellite antenna (e.g., steering a beam of the electronically steerable satellite antenna) to determine a direction of incidence of each of the plurality of signals on the electronically steerable satellite antenna. A set physical orientation of the electronically steerable satellite antenna relative to the Earth is then calculated based on the position of the electronically steerable satellite antenna and the direction of incidence of each of the signals from the satellite. The set physical orientation includes a rotation of an azimuth angle, an elevation angle, and a boresight direction of the electronically steerable satellite antenna relative to the Earth.

[0007] This Summary is provided to introduce selected concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0008] Other implementations are also described and enumerated herein. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 illustrates an example of a satellite communication system. [Diagram 2] FIG. 2 illustrates an example of an electronically steerable satellite antenna according to the present disclosure relative to a local coordinate system. [Diagram 3] FIG. 3 illustrates a schematic diagram of an antenna system of a user terminal. [Figure 4] FIG. 4 illustrates an example operation for determining the set physical orientation of an electronically steerable satellite antenna. [Diagram 5] FIG. 5 illustrates an exemplary configuration in which an electronically steerable satellite antenna receives signals from multiple satellites. [Figure 6] FIG. 6 illustrates an exemplary operation for mitigation of interference between a user terminal's electronically steerable satellite antenna and a non-targeted satellite. [Figure 7] FIG. 7 illustrates an example configuration in which off-axis emissions of the radiation pattern of an electronically steerable satellite antenna may cause interference events. [Figure 8] FIG. 8 illustrates an example of a computing device capable of implementing certain aspects of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It is to be understood, however, that it is not intended to limit the invention to the particular forms disclosed, but rather, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the claims.

[0011] The present disclosure relates to an approach to improve the performance of a satellite antenna or user terminal in a non-GEO satellite communication system. The present disclosure recognizes the advantages of utilizing an electronically steerable satellite antenna to track one or more non-GEO satellites as they pass through the sky relative to a user terminal. For example, the use of an electronically steerable satellite antenna may avoid the need to provide a complex, expensive, and failure-prone mechanical tracking mechanism to physically move the satellite antenna. Rather, the steerable satellite antenna may be installed at a set physical orientation, and the electronically steerable satellite antenna may be controlled to direct a beam for reception and / or transmission of signals. Thus, the electronically steerable satellite antenna may provide a directional beam for transmission and / or reception of signals. Although it is referred to herein as a beam or radiation pattern being steerable, such use is generally intended to refer to the beam of the antenna for its ability to either direct the transmission of signals or direct the sensitivity to reception of signals at the antenna over a given scan angle relative to the boresight direction of the antenna. That is, descriptions of steered beams or directional beams or radiation patterns are not intended to be limited to transmitting signals from an antenna, but rather may also refer to controlling the direction of sensitivity of the antenna for receiving signals.

[0012] The set physical orientation of the satellite antenna may be accurately and precisely determined according to the approaches described herein. Determining the set physical orientation of the antenna allows for monitoring the radiation pattern of the satellite antenna for interference mitigation with non-target satellites. The improved accuracy provided by the approaches described herein may reduce the tolerance or margin of error of the avoidance angles for non-target satellites. In turn, antenna performance is improved by potentially reducing the number of interference mitigation actions required to avoid interference with other satellites (e.g., within a GEO arc or other non-GEO arcs).

[0013] An interference event may refer to a situation in which the radiation beam pattern of a signal transmitted from a satellite antenna reaches a threshold for beam power within an avoidance angle for a non-target satellite. The threshold may relate to a maximum amount of interference that can be tolerated to maintain operation of the non-target satellite. For example, in a non-GEO satellite communication system, a satellite antenna of a user terminal may be required to avoid directing signals into a GEO arc so as to reduce or eliminate any interference to GEO geostationary communication satellites operating in the same frequency band as the non-GEO satellite communication system. Interference may also occur with respect to non-target non-GEO satellites (e.g., senior licensed satellites, etc.). Specifically, an avoidance angle may be defined for a non-target satellite or GEO arc that defines a range within which radiation from the satellite antenna does not exceed some threshold (e.g., may be predefined according to operational parameters, may be defined by government regulations, or may be subject to license requirements).

[0014] As a result, the user terminal may need to perform interference mitigation operations (e.g., mute antenna transmission, reduce antenna power for transmission, or point to a different satellite for signal transmission) while the target satellite crosses into an avoidance angle relative to the GEO arc or relative to a non-target satellite. Because this is inconvenient for system operation, it is desirable to minimize the avoidance angle relative to either the GEO arc or other non-GEO arcs as much as possible to maximize the usefulness of the non-GEO satellite system.

[0015] As mentioned above, the avoidance angle is related to the range of angles over which a non-GEO user terminal must avoid transmitting signals to avoid interference with non-target satellites (e.g., to keep antenna transmit power below a threshold). The avoidance angle may apply to both the main beam emission of a satellite antenna as well as the off-axis emission of the satellite antenna. Such off-axis emission may be referred to as a side lobe of the radiation pattern. Typically, the avoidance angle includes an error range to ensure that interference requirements are met (e.g., the transmitted radiation from the satellite antenna remains below a threshold within the range of the avoidance angle). Because the beamwidth of an antenna, and therefore the amount of interference generated, depends on the physical orientation of the antenna, errors may occur that are compensated for by the error range. For example, a satellite antenna may be oriented with respect to multiple degrees of freedom (e.g., azimuth, elevation, and rotation) in its own coordinate system. A satellite antenna may have a beamwidth that varies depending on the scan angle from the antenna's boresight direction. Thus, two satellite antennas installed in the same location but with boresight directions oriented in different directions will have different beamwidths when communicating with the same target satellite. In addition, satellite antennas may have non-circular apertures resulting in asymmetric beams with narrow and wide beamwidth axes. Thus, the combined beamwidth (and therefore the amount of interference) directed at non-target satellites depends on the rotation of the installed satellite antenna. Furthermore, in some contexts, the radiated transmit power associated with the side lobes of the radiation pattern may reach a threshold within the avoidance angle. Thus, off-axis emissions may also be subject to interference within the avoidance angle of non-target satellites.

[0016] The avoidance angle is unique for each satellite antenna due to the antenna's location on the Earth and the antenna's particular orientation. Although the antenna's location (e.g., described using latitude, longitude, and elevation) can be observed at installation or obtained from a local GPS receiver, the exact antenna orientation is not very easy to determine (e.g., to an accuracy of much less than one degree in rotation, elevation, and azimuth), even if the antenna is professionally installed by a trained technician. Also, even if the antenna is initially mounted and positioned accurately, the antenna may move over time due to environmental issues (e.g., weather, geological subsidence, earthquakes) or other unintended disturbances (e.g., being hit by a football or lawnmower). Uncertainty in the satellite antenna's orientation can add several degrees of error to the avoidance angle, potentially doubling the avoidance angle. A larger avoidance angle results in more interference events, thus reducing antenna performance. Thus, by accurately determining the set physical orientation of the satellite antenna, the avoidance angle can be reduced in response to more accurately determining the set physical orientation of the antenna, and interference avoidance mitigation actions can be reduced. Thus, this disclosure presents example methods and apparatus that enable each satellite antenna in a non-GEO satellite communications system to determine its precise orientation, regardless of installation accuracy or changes in orientation over time.

[0017] Furthermore, knowing the exact orientation of the satellite antenna has advantages in coordination efforts for efficient spectrum sharing with other non-GEO systems. If the non-GEO systems are spatially separated, each system can use all available spectrum without interference. If there is an in-line event, the spectrum must be shared. Therefore, minimizing the avoidance angles with other non-GEO systems also has a significant advantage in capacity and speed for all non-GEO systems sharing the spectrum.

[0018] Systems and methods for accurately determining the orientation of an electronically steerable satellite antenna are described herein. In doing so, avoidance angles for non-target satellites can be accurately calculated with reduced margin of error, thereby allowing maximum use of the satellite antenna. As described in more detail below, the present disclosure generally involves the use of an electronically steerable satellite antenna that receives multiple signals from at least two different satellites at known orbital positions relative to the Earth. In one example, one or more of the multiple signals received by the antenna may include a beacon signal. In other examples, one or more of the multiple signals may be other types of signals, such as communication signals, location signals, or any other type of signal detectable from a satellite at a known orbital position (e.g., based on known or available satellite orbit data for the satellite).

[0019] In addition, the position of the satellite antenna relative to the Earth may be determined. Using the position of the satellite antenna relative to the Earth and the known orbital positions of at least two different satellites, the direction of incidence of multiple signals received at the satellite antenna may be determined. The determined system of equations may then be calculated to analyze the set physical orientation of the satellite antenna, including the azimuth, elevation, and rotation of the satellite antenna. In connection with receiving the signals, an automatic algorithm may be performed by the antenna electronically scanning the sky for signals from two or more satellites having known positions (e.g., by controlling the direction of the satellite antenna beam over a range of azimuth and elevation angles). Thus, once at least two signals are found and identified, the satellite antenna may calculate a precise set physical orientation based on the scan angle (e.g., relative to azimuth and elevation) at which the signals were received. This automatic algorithm may be repeated as many times as necessary over the life of the satellite antenna.

[0020] In addition, the present disclosure recognizes that the radiation pattern of an electronically steerable satellite antenna includes a main radiation beam and auxiliary beam components, sometimes referred to as off-axis emissions or side lobes of the antenna's radiation pattern. It is then important to avoid interference between the main beam and non-target satellites. Accurate determination of the set physical orientation of the antenna helps to precisely model the main beam pattern for these purposes. In addition, accurate determination of the set physical orientation of the antenna is also important to avoid interference caused by side lobes of the radiation pattern. Thus, once the set physical orientation of the satellite antenna is determined, the known radiation pattern of the satellite antenna can be correlated against the set physical orientation for use in analyzing interference events of the satellite antenna when radiation within the avoidance angle reaches a threshold.

[0021] Referring to FIG. 1, an example of a satellite communication system 100 according to the present disclosure is shown. The system 100 includes a satellite antenna 120 supported by a mounting bracket 122 to place the satellite antenna 120 at a set physical orientation relative to the Earth. By set physical orientation, it is meant that the mounting bracket 122 is designed to place the antenna 120 at a static physical orientation that changes under normal operating conditions to which the antenna may be exposed, including, for example, weather events, geological subsidence, earthquakes, accidental physical contact with the antenna 120, etc. As described in more detail below, the mounting bracket 122 may establish a set physical orientation of the antenna 120 in azimuth, elevation, and rotation angles. The azimuth, elevation, and rotation angles may be measured with respect to the local coordinate system of the antenna 120 or a global coordinate system. It may further be appreciated that the orientation of the antenna 120 may be readily transformed between local and global coordinate systems as needed.

[0022] In one example, the orientation of the antenna 120 is measured relative to the boresight direction of the antenna 120. For example, the antenna 120 may include an electronically steerable satellite antenna. In this regard, the antenna 120 may include a boresight direction in which the gain of the antenna 120 is maximum. In the case of a planar phased array antenna, the boresight direction may be a vector normal to the planar phased array surface. Although the electronically steerable satellite antenna 120 may operate to steer the beam (e.g., by controlling the transmit direction and / or receive sensitivity) relative to the boresight direction (e.g., over a scan angle relative to the boresight direction), the set physical orientation of the antenna 120 may be measured using the boresight direction as a fixed reference datum for the antenna 120.

[0023] The antenna 120 may communicate bidirectionally with a satellite in orbit around the Earth (e.g., the target satellite 110). The target satellite 110 may also communicate bidirectionally with a gateway terminal 130 on Earth. The gateway terminal 130 may communicate with a network 140. The gateway terminal 130 may also be referred to as a hub or a ground station. The gateway terminal 130 includes an antenna that transmits forward uplink signals 132 to the target satellite 110 and receives return downlink signals 134 from the target satellite 110. The gateway terminal 130 may also schedule traffic to the antenna 120. Alternatively, scheduling may be performed in other parts of the satellite communication system 100 (e.g., a core node, a satellite access node, or other components, not shown). The communication signals 132, 134 communicated between the gateway terminal 130 and the target satellite 110 may use the same, overlapping, or different frequencies as the communication signals 136, 138 communicated between the target satellite 110 and the antenna 120.

[0024] The network 140 is interfaced with the gateway terminal 130. The network 140 can be any type of network, including, for example, the Internet, an IP network, an intranet, a wide area network (WAN), a local area network (LAN), a virtual private network (VPN), a virtual LAN (VLAN), an optical fiber network, a cable network, a public switched telephone network (PSTN), a public switched data network (PSDN), a public land mobile network, and / or any other type of network supporting communication between devices as described herein. The network 140 can include both wired and wireless connections, as well as optical links. The network 140 can connect multiple gateway terminals 130 that can communicate with the target satellite 110 and / or other satellites.

[0025] The gateway terminal 130 may be provided as an interface between the network 140 and the target satellite 110. The gateway terminal 130 may be configured to receive data and information from sources accessible via the network 140 bound for the antenna 120. The gateway terminal 130 may format the data and information and transmit a forward uplink signal 132 to the target satellite 110 for distribution to the antenna 120. Similarly, the gateway terminal 130 may be configured to receive a return downlink signal 134 from the target satellite 110 (e.g., including data and information originating from the antenna 120) bound for a destination accessible via the network 140. The gateway terminal 130 may also format the received return downlink signal 134 for transmission over the network 140.

[0026] The target satellite 110 can receive a forward uplink signal 132 from the gateway terminal 130 and transmit a corresponding forward downlink signal 136 to the antenna 120. Similarly, the target satellite 110 can receive a return uplink signal 138 from the antenna 120 and transmit a corresponding return downlink signal 134 to the gateway terminal 130. The target satellite 110 can operate in a multi-spot beam mode, transmitting and receiving several narrow beams directed toward different regions on the Earth. Alternatively, the target satellite 110 can operate in a wide area coverage beam mode, transmitting one or more wide area coverage beams.

[0027] Target satellites 110 may be configured as "bent pipe" satellites that perform frequency and polarization conversion of received signals before retransmitting the signals to their destination. As another example, target satellites 110 may be configured as regenerative satellites that demodulate and remodulate received signals before retransmission.

[0028] As shown in FIG. 1, the satellite communication system 100 also includes another satellite, hereafter referred to as a non-targeted satellite 112. Communication of one or more signals between the non-targeted satellite 112 and the antenna 120 is not desired or intended. Although only one non-targeted satellite 112 is illustrated in FIG. 1 to avoid overcomplexity of the drawing, the satellite communication system 100 may include more non-targeted satellites 112 and may use the techniques described herein to avoid excessive interference with each of the non-targeted satellites 112. The non-targeted satellites 112 may be part of the same satellite constellation as the targeted satellite 110 or may be members of a different satellite constellation. The non-targeted satellites 112 may be satellites operated by a different satellite operator than that of the targeted satellite 110. For example, in some jurisdictions, licensing regimes or other protocols may provide location information (e.g., satellite orbit data) for the non-targeted satellites 112 and dictate interference protocols including, for example, priorities among multiple satellites that may be visible to the antenna 120.

[0029] Non-targeted satellites 112 may be configured, for example, as bent pipe or regenerative satellites. Non-targeted satellites 112 may communicate one or more signals with one or more ground stations (not shown) and / or other terminals (not shown).

[0030] Antenna 120 may include a control system that controls communications with target satellites 110 while also avoiding undue interference with non-target satellites 112. Examples of such antenna systems are described in more detail below.

[0031] As used herein, interference to a non-targeted satellite 112 can refer to uplink interference and / or downlink interference. Uplink interference is interference to a non-targeted satellite 112 caused by a portion of a return uplink signal 138 transmitted by antenna 120 that is received by the non-targeted satellite 112. Downlink interference is interference to antenna 120 caused by a portion of a signal transmitted by a non-targeted satellite 112 that is received by antenna 120.

[0032] Non-targeted satellites 112 may be GEO satellites in a GEO arc relative to antenna 120. Furthermore, interference with a GEO arc relative to antenna 120 may be avoided regardless of the identification of any particular GEO satellite in the GEO arc. Alternatively, non-targeted satellites 112 may be non-GEO satellites whose orbital position information may be provided by satellite orbit data. In one example, targeted satellites 110 may be LEO satellites and non-targeted satellites 112 may be GEO satellites. In some embodiments, non-targeted satellites 112 may include multiple GEO satellites in a GEO arc in which the GEO satellites are distributed. In alternative embodiments, one or both of targeted satellites 110 and non-targeted satellites 112 may be LEO satellites. Non-targeted satellites 112 may be adjacent to targeted satellite 112, for example. As used herein, targeted satellites 110 and non-targeted satellites 112 are "adjacent" if the effective angular distance between them as viewed by antenna 120 is 10 degrees or less. In this regard, the avoidance angles of adjacent non-target satellites may be greater than the actual angular separation to provide a margin of error for avoiding interference.

[0033] With further reference to FIG. 2, an example of antenna 200 is shown in more detail. Antenna 200 may include an electronically steerable satellite antenna, such as a phased array antenna. In other examples, other electronically steerable satellite antennas other than, but not limited to, a phased array antenna may be provided. For example, the electronically steerable satellite antenna may include a liquid crystal polymer based aperture antenna, a counter rotated aperture antenna coupled with a slot plate, an antenna utilizing barium strontium titanite or other similar voltage dependent dielectric material, or a metamaterial based antenna. In one example, antenna 200 may include a plurality of antenna elements 224. The plurality of antenna elements 224 may include an antenna array and beam forming circuitry (e.g., phase shifters, amplifiers, etc.) that may be collectively controlled to provide a steerable beam. The steerable beam may enable, but is not limited to, directional reception of signals and / or directional transmission of signals in the direction of the steered beam. Although a rectangular array of rectangular antenna elements 224 is shown in FIG. 2, it can be understood that any configuration, shape, and / or array of antenna elements 224 can be provided without limitation (including, for example, antenna elements 224 of different shapes, such as triangular, hexagonal, octagonal, or other polygonal shapes, in any suitable array layout).

[0034] The antenna 220 may be supported by a mounting bracket 222. The mounting bracket 222 may in turn be fixed to a base 226. The base 226 may be a permanent or static structure relative to the Earth. For example, the base 226 may include a mounting pad, a building, or any other static structure. The mounting bracket 222 may provide one or more degrees of freedom to the antenna 220 to set the physical orientation of the antenna 220. In one example, the mounting bracket 222 may provide at least three degrees of freedom in which the azimuth, elevation, and rotation angles of the antenna 220 may be adjusted. Regardless of the adjustability of the mounting bracket 222, the mounting bracket 222 may be fixed to position the antenna 220 in a set physical orientation. As described above, the set physical orientation may be static such that the operating conditions to which the antenna 220 is exposed do not cause the antenna 220 to move.

[0035] 2 illustrates an example coordinate system 230 in which a set physical orientation of the antenna 220 may be described. The coordinate system 230 may include x-, y-, and z-axes that define a local three-dimensional coordinate system relative to the antenna 220. A boresight direction 240 of the antenna 220 may be located within the coordinate system 230. As described above, the boresight direction 240 of the antenna 220 describes the axis of maximum gain of the antenna 220. In the case of an electronically steerable satellite antenna, the beam may be steerable through a scan angle relative to the boresight direction 240 without physical movement of the antenna 220.

[0036] 2, the boresight direction 240 may be described in coordinate system 230 by azimuth angle 234, elevation angle 232, and rotation angle 236. Because coordinate system 230 may be static in a reference frame relative to the Earth, azimuth angle 234, elevation angle 232, and rotation angle 236 may completely describe the set physical orientation of antenna 220 relative to the Earth. That is, azimuth angle 234, elevation angle 232, and rotation angle 236 may be converted between a local coordinate system (e.g., coordinate system 230) and a global coordinate system relative to the Earth.

[0037] When installing or configuring the antenna 220, it may be possible to approximate the set physical orientation of the antenna 220. However, such approximations may introduce inaccuracies that may affect the performance of the antenna by resulting in a larger error range for the interference angle. For example, a relatively low accuracy measurement of the set physical orientation of the antenna 220 may require an increased tolerance of the avoidance angle for interference mitigation, as described above, to acceptably reduce the risk of interference to non-target satellites. Thus, even if the antenna 220 is installed by a technician trained in installation and measurement, the accuracy that may be achieved in such measurements may not be sufficient to accurately determine interference events without degradation of antenna performance. Furthermore, in many cases, the antenna 220 is installed and / or configured by untrained users, such as homeowners or other end users, without training in orientation or orientation measurements. Therefore, it is advantageous to provide an automated measurement of the set physical orientation of the antenna 220 using a process described in more detail below.

[0038] 3 presents a schematic diagram of an antenna system 300. An antenna 320 is illustrated generally as being supported by a mounting bracket 322, along with an antenna element 324. In this respect, the antenna 320 may correspond to the foregoing description of the antenna 220 described above.

[0039] The antenna 320 may be in communication with an antenna controller 350, which may be in operative communication with the transceiver 310. The transceiver 310 may be in communication with the antenna controller 350, which may include control circuitry or other means for controlling operation of the antenna 320 to facilitate communication with a target satellite (not shown in FIG. 3). For example, the transceiver 310 may instruct the antenna controller 350 to control the antenna elements 324 to steer the beam of the antenna 320 over scan angles relative to the azimuth and elevation angles relative to the antenna 320. Such control of the antenna elements 324 allows the beam of the antenna to be directed over a range of scan angles relative to the antenna's boresight direction.

[0040] The transceiver 310 may amplify and then downconvert a forward downlink signal (as shown in FIG. 1) from a target satellite to generate an intermediate frequency (IF) receive signal for delivery to the modem 340. Similarly, the transceiver 310 may upconvert and then amplify an IF transmit signal received from the modem 340 to generate a return uplink signal (as shown in FIG. 1) for delivery to the target satellite. In some embodiments where the target satellite operates in a multi-spot beam mode, the frequency ranges and / or polarizations of the return uplink and forward downlink signals may be different for the various spot beams. Thus, the transceiver 310 may be within the coverage area of ​​one or more spot beams and may be configurable to match the polarization and frequency range of a particular spot beam. The modem 340 may be located, for example, inside the structure to which the antenna 320 is attached. As another example, the modem 340 may be located on the antenna 320, such as incorporated within the transceiver 310. In any case, the transceiver 310 may receive and transmit signals via the antenna 320 to provide communication capabilities for the modem 340 (e.g., to facilitate access between the modem 340 and a network). That is, the modem 340 may modulate and demodulate IF receive and transmit signals, respectively, to communicate data with a router (not shown). The router may route data between one or more connected devices 342, such as, for example, laptop computers, tablets, cell phones, etc., to provide two-way data communications, such as two-way Internet and / or telephone service.

[0041] The antenna controller 350 may also be in communication with an orientation calculation module 312. The orientation calculation module 312 may comprise a processor in operative communication with a memory that accesses machine-readable instructions for executing algorithms for controlling the antenna 320 to determine a set physical orientation of the antenna 320. The orientation calculation module 312 may then analyze the orientation of the antenna 320, as described in more detail below.

[0042] The orientation calculation module 312 may be in communication with the location module 314. The location module 314 may operate to determine a location of the antenna 320 (e.g., described by latitude, longitude, and altitude). The location module 314 may then provide the location of the antenna 320 to the orientation calculation module 312 for use in determining the set physical orientation of the antenna 320. The location module 314 may comprise, for example, a Global Positioning System (GPS) receiver capable of resolving the position of the antenna 320 on the Earth (e.g., relative to a universal coordinate system such as using latitude, longitude, and altitude). Any other suitable location determination technology may be used by the location module 314 without limitation.

[0043] The orientation calculation module 312 may determine the direction of incidence from signals received from satellites in known orbital positions. As discussed in more detail below, a scanning operation performed by an electronically steerable satellite antenna may be used to determine the direction relative to the antenna in an initially unknown set physical orientation in which signals are received from satellites in known orbital positions. In one example, the orbital positions may be determined by the orientation calculation module 312 utilizing satellite orbit data for the satellites. Alternatively, the satellite orbit data may be used to remotely determine the orbital positions of the satellites such that the position information is communicated to the orientation calculation module 312.

[0044] The orientation calculation module 312 may also be in operative communication with the scheduler 330. The scheduler 330 may maintain or receive satellite orbit data for the target satellites and / or non-target satellites. In this regard, the satellite orbit data of the scheduler 330 may be analyzed to identify interference events in which the interference threshold of the radiation emitted by the antenna 320 reaches an avoidance angle. As discussed above, the interference events may be associated with signals transmitted along a side lobe of the main beam or radiation pattern of the antenna 320. The scheduler 330 may determine an appropriate interference mitigation action in response to the identified interference event. The interference mitigation action may include targeting a new target satellite from which interference is avoided. This may require that an alternative target satellite of the satellite communication system be available (e.g., within the view of the satellite antenna 320). Thus, the interference mitigation action may alternatively include modifying the characteristics of the beam of the antenna 320. For example, the main beam may be compromised or the transmit power of the beam may be reduced, thus potentially reducing the maximum gain of the beam but potentially reducing the interfering emissions below a threshold. Additionally, transmission characteristics such as frequency, modulation data rate, error correction coding, modulation type, coding, or other characteristics may be modified to mitigate interference to non-targeted satellites (e.g., in conjunction with the targeted satellite).

[0045] In some examples, one or more of the antenna controller 350, the transceiver 310, the modem 340, the orientation calculation module 312, the position module 314, and / or the schedule 330, while shown as separate modules in FIG. 3 for clarity, may be provided integral with the antenna 320. Additionally, some of the above-listed modules may be located remotely from the antenna 320 and / or a user terminal associated with the antenna, such that the functionality of the modules may be facilitated through network communications (including, for example, communications using communications with target satellites).

[0046] 4 illustrates example operations 400 of a process for determining a set physical orientation of a satellite antenna. The operations 400 may include an installation operation 402 in which the satellite antenna is installed in a set physical orientation. As described above, the installation operation 402 may be performed by an end user, a trained technician, or some other user. In either case, the installation operation 402 may include fixing the satellite antenna relative to a fixed structure to statically position the satellite antenna in the set physical orientation.

[0047] The operations 400 may also include a location determining operation 404 in which a location of the installed antenna is determined. As described above, the location determining operation 404 may be performed by a location module. In one example, the location determining operation 404 may include analyzing the position of the satellite antenna relative to the Earth using a GPS receiver. This may provide an accurate determination of the latitude, longitude, and altitude of the satellite antenna relative to the Earth.

[0048] A scanning operation 406 may be performed in which the steerable beam of the satellite antenna is scanned through a range of azimuth and elevation angles. That is, the satellite antenna may have a scan angle that describes the angle relative to the satellite's boresight direction at which the steerable main beam may be pointed, effectively providing a field of view of the satellite. Concurrent with the scanning operation 406, a measuring operation 408 may measure a received signal strength indicator (RSSI) of one or more signals.

[0049] As described above, the signals may include beacon signals that are provided specifically for the purpose of determining the direction of incidence of the signal relative to the antenna. Other types of signals may also be utilized along with or as an alternative to one or more beacon signals. For example, the signals may be received from a satellite of a satellite communications system. In such an example, the satellite antenna may be able to receive system control messages by reception of the satellite signals or by another communications network. The satellite antenna may then be able to identify the satellite from the system control messages. This functionality may be provided by a user terminal to obtain and establish communications with a satellite of the satellite system.

[0050] Alternatively, if a satellite from outside the satellite communication system is utilized to receive one or more of the signals, reception of such signals may be performed according to publicly available information. For example, if the satellite is a GPS satellite, GPS protocols may be publicly available for use in obtaining such signals and / or determining the satellite's location in its orbital position (e.g., based on publicly available satellite orbit data). If the satellite includes a third-party owned satellite outside the satellite communication system, public information of the license application or other public record of such satellite may be provided. This public information may enable a satellite antenna to match the frequency, carrier bandwidth, modulation type, or other signal characteristics, which may be referred to as external signal characteristics. The external signal characteristics may be recognizable by a receiver without the need to interpret or demodulate the signal. Thus, information derived from the external signal characteristics may be determined and used to identify the direction of incidence from a satellite in a known position (e.g., based on publicly available satellite orbit data) without the need to demodulate or receive a message associated with the signal. Rather, the system may compare the external signal characteristics of a signal to a public or otherwise accessible database of those characteristics to uniquely identify the satellite in question.

[0051] Further, the system may first attempt to receive signals from a satellite in a satellite communication system. If no signals are available, the system may attempt to receive signals from a publicly accessible system (e.g., GPS signals). Finally, if satellite communication system signals or publicly accessible signals are not available, third-party owned signals having publicly available external characteristics may be utilized. Furthermore, in one example, at least one of the signals may be received from a non-satellite transmitter, such as an unmanned aerial vehicle (UAV), a manned flying platform, a balloon, or other transmitter platform at a known position relative to the Earth. In such an example, the location of the non-satellite transmitter may be otherwise known (e.g., using GPS, etc.) or may be derived.

[0052] Scanning operation 406 and measuring operation 408 may then generate information regarding signal strength across a scan angle for a plurality of signals received from two or more satellites. As described above, the satellites may be in known orbital positions relative to the Earth. For example, satellite orbit data for the satellites may be known or may be obtained to determine the satellite's exact position at the time of transmission of the signals. In any case, information regarding the orbital positions of the satellites from which the plurality of signals are received may be used in determining operation 410, in which a direction of incidence of each of the plurality of signals is determined.

[0053] In one example, the scanning operation 406 may include scanning the antenna's beam over the full range of azimuth and elevation angles at which the antenna's beam may be steered (e.g., by a full sweep of all scan angles relative to the boresight direction). The scanning operation 406 may include a full power scan in which the electronically steerable antenna's beam is controlled. In another example, the beam may be widened such that a wider radial spread sensitivity is provided with less receive gain. A wider radiation pattern sensitivity with less maximum receive gain may be used to initially scan more quickly over the azimuth and elevation angles of the scan due to the beam's wider radial spread sensitivity. Once the signal is initially located, subsequent scans may be performed using narrower beams with higher gain in a more limited range of azimuth and elevation angles than those identified by the initial wide beam scan.

[0054] Reception of multiple signals from one or more satellites is further illustrated in Figure 5. Figure 5 illustrates a satellite antenna 520 at a known position on Earth 530 (e.g., as determined by a GPS receiver). The satellite antenna 520 may be controlled to scan a beam over a range of azimuth and elevation angles. During the course of the scan, the RSSI of the signals 514, 516 may be measured. The signals 514, 516 may be received from at least two different satellites 510, 512 at known orbital positions.

[0055] As can be understood from the foregoing disclosure, when determining the orientation of the antenna 520, the unknown variables include the azimuth, elevation, and rotation of the satellite antenna 520. For these three unknowns, a system of equations can be generated to solve for the three unknowns of the azimuth, elevation, and rotation of the satellite antenna 520. The system of equations can be solved using three inputs related to the unknown angles including the orientation of the antenna 520. Thus, the known position of the antenna 520 on the Earth can represent a first input. In this regard, two or more signals received at the antenna 520 from satellites 510, 512 of known orbital positions (e.g., using satellite orbit data for the satellites 510, 512) can provide at least two additional inputs to create a determined system of equations that allows the three unknowns to be solved. Thus, at least two signals 514, 516 can be received. In one example, signals 514, 516 may be received from each of multiple satellites 510, 512 to provide the two inputs required to a system of equations to determine a set physical orientation of the antenna 520. The corresponding direction of incidence of each of the signals may be determined (e.g., based on where the signal strength of the respective beacon signal was greatest during a scan, given the known position of the satellite antenna 520 on Earth and the known orbital positions of the satellites 510, 512). The direction of incidence of the signals 514, 516 may provide the remaining two inputs required to provide a determined system to determine the azimuth, elevation, and rotation angles of the antenna 520.

[0056] As illustrated in FIG. 5, the two satellites 510, 512 may be at different orbital locations relative to the antenna 520. Using two different satellites at different orbital locations relative to the antenna 520 may provide an improved geometric dilution of precision (GDOP) value. However, it may be possible to measure two or more signals from the same satellite at different times where the satellites are at different orbital locations providing sufficient GDOP. In a further example, the satellites 510, 512 may each be a GEO satellite at a known orbital location within a GEO arc. In another example, one or both of the satellites 510, 512 may be a non-GEO satellite. In the case of a non-GEO satellite, satellite orbit data for the time the signals 514, 516 were transmitted may be available to the antenna 520 to enable the precise orbital location of the non-GEO satellite to be determined when the signals 514, 516 were received.

[0057] 4, analysis operation 412 may include analyzing the azimuth, elevation, and rotation angles of the satellite antenna. Analysis operation 412 may include constructing and / or solving the system of equations described above that utilizes the position of the antenna on Earth and two directions of incidence for the signal received at the antenna from the known orbital positions of each satellite from which the signal is received as inputs to solve for three unknown variables: the azimuth, elevation, and rotation angles of the satellite antenna.

[0058] The analysis operation 412 may determine the set physical orientation of the satellite antenna to an accuracy of less than one degree. For example, the analysis operation 412 may determine the set physical orientation of the satellite antenna to an accuracy of about 0.5 degrees, 0.1 degrees, or 0.01 degrees or less. In this respect, the accuracy achieved by the analysis operation 412 based on signals received at the satellite antenna may far exceed the accuracy that may be achieved by physical measurements or by a user aiming the satellite antenna through steering the satellite antenna relative to a mounting bracket. Determining a more accurate orientation may reduce the avoidance angle for non-target satellites. The number of interference mitigation operations may then be reduced based on the reduction in avoidance angles that may be achieved in light of the determination of the accurate satellite antenna orientation.

[0059] 6 illustrates example operations 600 for mitigating interference with an electronically steerable satellite antenna. The operations 600 include a determining operation 602 for determining a set physical orientation of the satellite antenna. The determining operation 602 may include, but is not limited to, the operations 400 described in connection with FIG. 4 above.

[0060] The operations 600 may also include an acquisition operation 604 of acquiring radiation pattern information for the antenna. The radiation pattern information may be received at the antenna or may be determined locally. The information about the radiation pattern may include a beam pattern projection profile. For example, for a phased array antenna, known equations may be provided to model the radiation pattern of the antenna. In particular, the beam pattern projection profile of the antenna may be modeled for any direction in which the beam of the antenna is steered across all scan angles available relative to the boresight direction of the antenna.

[0061] Next, operations 600 may also include an association operation 606 in which the transmit radiation pattern for the antenna is associated with (e.g., aligned with) the established physical orientation. For example, the beam pattern projection profile may be characterized as radiation vectors of various magnitudes relative to the antenna's beam direction. Just as the orientation may characterize the antenna's boresight direction in a global coordinate system relative to the Earth, association operation 606 may include transforming the radiation pattern to a global coordinate system such that the radiation pattern may be described or expressed with respect to the Earth for any available scan angle of the antenna's beam.

[0062] Next, the operations 600 may include an analysis operation 608 in which a radiated transmission vector describing the transmit radiation pattern of the antenna is analyzed to identify any potential interference events. The potential interference events may be determined with respect to one or more side lobes of the main beam and / or off-axis emissions of the radiation pattern. The analysis operation 608 may include ingesting satellite orbit data for the non-targeted and targeted satellites (e.g., from the scheduler 330). A relative position of the GEO arc with respect to the antenna may be determined and an avoidance angle established therefor. Additionally or alternatively, an avoidance angle may be established for one or more non-GEO non-targeted satellites. In any event, an avoidance angle may be determined at which the radiated emissions must remain below a threshold.

[0063] The identification operation 610 may occur when an interference event is determined in which radiation emission from the antenna reaches a threshold at an avoidance angle. The identification operation 610 may be performed in consideration of the satellite orbit data received during the analysis operation 608. Additionally, in connection with the identification operation 610, the satellite orbit data may also be analyzed to determine options for interference mitigation. For example, in connection with identifying an interference event, it may also be determined whether a new target satellite is in view of the satellite antenna and whether retargeting the satellite antenna to the new target satellite will mitigate the interference. It may be appreciated that in a non-GEO user terminal, retargeting to the satellite antenna may occur periodically in view of the target satellite transitioning out of view from the satellite antenna. Thus, retargeting to the new target satellite in response to identifying an interference event may include an unscheduled transition. An unscheduled transition may correspond to a planned transition that may be performed earlier than scheduled to mitigate the interference event. Alternatively, the identification operation 610 may include identifying a new target satellite that was not previously scheduled for targeting by the satellite antenna in response to identifying an interference event.

[0064] The identification operation 610 may be performed locally at the antenna and / or user terminal, or may be performed remotely. For example, a scheduler module may be located at the antenna and periodically populated with and updated with satellite orbit data. Thus, the user terminal may autonomously determine a schedule for the target satellite, including any targeting changes that mitigate the interference event, and coordinate such schedule directly with the target satellite to maintain continuous communication between the satellite antenna and at least one target satellite. Alternatively, such scheduling may be performed remotely from the user terminal, and the schedule may be communicated to the user terminal for execution. Of note, the identification operation 610 may pre-identify any such interference event based on predicted satellite orbit data for the target and non-target satellites prior to the actual occurrence of the interference event.

[0065] Additionally, the interference event may be identified in the identification operation 610 as being associated with the satellite antenna's main beam or off-axis emission, as described above. With further reference to FIG. 7, an exemplary scenario 700 is shown. In FIG. 7, a satellite antenna 720 is steering a main beam 722 of a transmit radiation pattern 730 along a main beam axis 724 in the direction of a target satellite 710. Notably, the main beam axis 724 may be outside of any avoidance angle with respect to either the GEO arc or the non-target satellite. However, the radiation pattern 730 may also have off-axis emission including side lobes 726a and 726b. As can be appreciated, the side lobe 726b may not be interfering with any non-target satellite. However, the side lobe 726a may extend along a side lobe axis 728a. As can be appreciated, the side lobe axis 728a may be at an avoidance angle with respect to the non-target satellite 712. Further, the magnitude of the radiation emission of the side lobe 726a may reach a threshold for interference to non-targeted satellites 712. Thus, in Figure 7, an interference event may be identified in relation to the side lobe 726a. The radiation pattern 730 and / or other transmission characteristics of the antenna 720 may then be modified, as described below, to mitigate potential interference between the side lobe 726a and the non-targeted satellites 712.

[0066] 6, in response to the identification operation 610, a modification operation 612 may be performed in which transmissions from the satellite antenna are modified. The modification operation 612 may include retargeting to a new target satellite so that the interference event may be avoided. Such information regarding an alternative target satellite may be provided by the scheduler 330, or the like. Additionally or alternatively, the beam shape of the satellite antenna's radiation pattern may be modified to avoid the interference. This may include modifying the radiation pattern shape and / or power to reduce any radiation directed within an avoidance angle with a non-target satellite below a threshold level.

[0067] 8 illustrates an exemplary schematic diagram of a computing device 800 suitable for implementing aspects of the disclosed technology, including an antenna controller 850 and / or an orientation determination module 852, corresponding to the examples described above. The computing device 800 includes one or more processor units 802, a memory 804, a display 806, and other interfaces 808 (e.g., buttons). The memory 804 generally includes both volatile memory (e.g., RAM) and non-volatile memory (e.g., flash memory). An operating system 810, such as a Microsoft Windows operating system, an Apple macOS operating system, or a Linux operating system, resides in the memory 804 and is executed by the processor unit(s) 802, although it should be understood that other operating systems may also be employed.

[0068] One or more applications 812 are loaded into memory 804 and executed on operating system 810 by processor unit 802. Applications 812 may receive input from various input local devices such as microphone 834, input accessories 835 (e.g., keypad, mouse, stylus, touchpad, joystick, on-board input, etc.). Additionally, applications 812 may receive input from one or more remote devices, such as remotely located smart devices, by communicating with such devices over a wired or wireless network using a number of communication transceivers 830 and antennas 838 to provide network connectivity (e.g., cellular networks, Wi-Fi, Bluetooth). Computing device 800 may also include various other components, such as a positioning system (e.g., a global positioning satellite transceiver), one or more accelerometers, one or more cameras, an audio interface (e.g., microphone 834, audio amplifier and speaker and / or audio jack), and storage device 828. Other configurations may also be employed.

[0069] Computing device 800 further includes a power supply 816 that is powered by one or more batteries or other power sources and provides power to other components of computing device 800. Power supply 816 may also be connected to an external power source (not shown) that overrides or recharges the internal battery or other power source.

[0070] In an example implementation, computing device 800 comprises hardware and / or software embodied by instructions stored in memory 804 and / or storage device 828 and processed by processor unit(s) 802. Memory 804 may be memory of the host device or of an accessory that couples to the host. Additionally or alternatively, computing device 800 may comprise one or more field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), or other hardware / software / firmware capable of providing the functionality described herein.

[0071] Computing device 800 may include a variety of tangible processor-readable storage media and intangible processor-readable communication signals. Tangible processor-readable storage media may be embodied by any available medium that can be accessed by computing device 800, including both volatile and nonvolatile storage media, removable and non-removable storage media. Tangible processor-readable storage media includes volatile and non-volatile removable and non-removable storage media implemented in any method or technology for storage of information such as processor-readable instructions, data structures, program modules, or other data, excluding intangible communication signals. Tangible processor-readable storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other tangible media that can be used to store the desired information and that can be accessed by computing device 800. In contrast to tangible processor-readable storage media, an intangible processor-readable communication signal may embody processor-readable instructions, data structures, program modules, or other data present in a modulated data signal, such as a carrier wave or other signal transport mechanism. The term "modulated data signal" means an intangible communication signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, intangible communication signals include signals that pass through wired media, such as a wired network or direct-wired connection, and wireless media, such as acoustic, RF, infrared, and other wireless media.

[0072] Some implementations may include an article of manufacture. The article of manufacture may comprise a tangible storage medium that stores logic. Examples of storage media may include one or more types of processor-readable storage media capable of storing electronic data, including volatile or non-volatile memory, removable or non-removable memory, erasable or non-erasable memory, writable or rewritable memory, and the like. Examples of logic may include various software elements, such as software components, programs, applications, computer programs, application programs, system programs, machine programs, operating system software, middleware, firmware, software modules, routines, subroutines, operation segments, methods, procedures, software interfaces, application program interfaces (APIs), instruction sets, computing code, computer code, code segments, computer code segments, words, values, symbols, or any combination thereof. In one implementation, for example, the article of manufacture may store executable computer program instructions that, when executed by a computer, cause the computer to perform methods and / or operations according to the described implementations. The executable computer program instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, and the like. The executable computer program instructions may be implemented according to a predefined computer language, style, or syntax to instruct a computer to perform a particular operation segment. The instructions may be implemented using any suitable high-level, low-level, object-oriented, visual, compiled, and / or interpreted programming language.

[0073] One general aspect of the disclosure includes a method for determining a set physical orientation of an electronically steerable satellite antenna for use in a satellite communication system. The method includes determining a position of the electronically steerable satellite antenna relative to the Earth. The method also includes receiving a plurality of signals from at least two different respective satellites. The method includes electronically steering a beam of the electronically steerable satellite antenna to determine a direction of incidence of each of the plurality of signals relative to a boresight direction on the electronically steerable satellite antenna. The method then includes calculating a set physical orientation of the electronically steerable satellite antenna relative to the Earth based on the position of the electronically steerable satellite antenna and the direction of incidence of each signal from the satellite. The satellite from which the plurality of signals are received is in a known orbital position relative to the Earth. The set physical orientation includes a rotation of an azimuth angle, an elevation angle, and a boresight direction of the electronically steerable satellite antenna relative to the Earth.

[0074] Implementations may include one or more of the following features. For example, the method may also include determining a beam pattern projection profile for the electronically steerable satellite antenna and associating the beam pattern projection profile with a set physical orientation of the electronically steerable satellite antenna. In one example, the beam pattern projection profile is asymmetric.

[0075] In one example, the method includes steering a beam of an electronically steerable satellite antenna to communicate a signal between the electronically steerable satellite antenna and a target satellite, and detecting an interference event based on a beam pattern emission profile of the electronically steerable satellite antenna at a set physical orientation. The interference event may include an emission from the electronically steerable satellite antenna reaching a predetermined level with respect to a non-target satellite. In one example, the interference event may be based on a side lobe emission apart from a main beam emission of the beam pattern emission profile.

[0076] The method may include modifying a transmission of the electronically steerable satellite antenna in response to an interference event. In one example, the interference event may be with a geosynchronous orbit of a non-targeted satellite. Additionally or alternatively, the interference event may be with a non-targeted satellite in low Earth orbit.

[0077] In one example, the electronically steerable satellite antenna may be a phased array satellite antenna. Determining the direction of incidence of each of the plurality of signals relative to a boresight direction of the electronically steerable satellite antenna may include electronically steering a beam of the satellite antenna to scan over a range of azimuth angles and a range of elevation angles. The direction of incidence of each of the plurality of signals may be determined based on the signal strength indications of the signals relative to the range of azimuth angles and the range of elevation angles.

[0078] In one example, at least one of the two different respective satellites includes a geosynchronous satellite. In one example, at least one of the two different respective satellites may be a low Earth orbit satellite. Thus, the known orbital position relative to the Earth may be based on satellite orbit data of the low Earth orbit satellite at a time reference corresponding to receipt of a signal from the low Earth orbit satellite.

[0079] In one example, calculating the set physical orientation may include resolving azimuth, elevation, and rotation to within an error of about 1 degree or less.

[0080] Another general aspect of the disclosure includes a system operative to determine an orientation of an electronically steerable satellite antenna for use in a satellite communications system. The system includes an electronically steerable satellite antenna. The electronically steerable satellite antenna electronically steers a beam of the electronically steerable satellite antenna to receive a plurality of signals from at least two different respective satellites. The system also includes a position module that determines a position of the electronically steerable satellite antenna relative to the Earth. The system further includes an orientation calculation module that determines a direction of incidence of each of the plurality of signals relative to a boresight direction of the electronically steerable satellite antenna given a known orbital position relative to the Earth. The orientation calculation module further calculates a set physical orientation of the electronically steerable satellite antenna relative to the Earth based on the position of the electronically steerable satellite antenna and the direction of incidence of each of the plurality of signals. The set physical orientation includes a rotation of an azimuth angle, an elevation angle, and a boresight direction of the electronically steerable satellite antenna relative to the Earth.

[0081] Implementations may include one or more of the following features. For example, an electronically steerable satellite antenna may have a beam pattern ejection profile. An orientation calculation module may then associate the beam pattern ejection profile with a set physical orientation of the electronically steerable satellite antenna. In one example, the beam pattern ejection profile may be asymmetric.

[0082] In one example, the electronically steerable satellite antenna may steer a beam of the electronically steerable satellite antenna to communicate signals between the electronically steerable satellite antenna and a target satellite. The system may include a scheduler that detects an interference event based on a beam pattern emission profile of the electronically steerable satellite antenna at a set physical orientation. The interference event may include an emission from the electronically steerable satellite antenna reaching a predetermined level with respect to a non-target satellite. In one example, the interference event may be based on a side lobe emission apart from a main beam emission of the beam pattern emission profile. The electronically steerable satellite antenna may modify transmissions in response to and prior to the interference event.

[0083] In one example, the interference event may relate to a non-targeted satellite in a geosynchronous orbit. Additionally or alternatively, the interference event may relate to a non-targeted satellite in a low Earth orbit.

[0084] In one embodiment, the electronically steerable satellite antenna may be a phased array antenna. The orientation calculation module may determine the direction of incidence of each of the multiple signals relative to a boresight direction of the electronically steerable antenna by electronically steering a beam of the electronically steerable satellite antenna to scan through a range of azimuth angles and a range of elevation angles to identify the direction of incidence. The direction of incidence of each of the multiple signals may be determined based on the signal strength indications of the multiple signals relative to the range of azimuth angles and the range of elevation angles.

[0085] In one example, at least one of the two different respective satellites includes a geosynchronous satellite. Additionally or alternatively, at least one of the two different respective satellites may be a low Earth orbit satellite, and the known orbital position relative to the Earth is based on satellite orbit data of the low Earth orbit satellite at a time reference corresponding to receipt of a signal from the low Earth orbit satellite.

[0086] In one example, the orientation calculation module may resolve azimuth, elevation, and rotation to within about 1 degree or less error.

[0087] The implementation aspects described herein are implemented as logical steps in one or more computer systems. Logical operations may be implemented (1) as a sequence of processor-implemented steps executed within one or more computer systems, and (2) as interconnected machine or circuit modules within one or more computer systems. The implementation is a matter of choice, depending on the performance requirements of the computer system being utilized. Thus, the logical operations making up the implementation aspects described herein are variously referred to as operations, steps, objects, or modules. Furthermore, it should be understood that logical operations may be performed in any order unless expressly claimed otherwise or a particular order is inherently necessitated by the claim language.

[0088] Although the present invention has been illustrated and described in detail in the drawings and the foregoing description, such illustration and description should be considered as exemplary and not restrictive in character. For example, certain embodiments described above can be combined with other described embodiments and / or arranged in other ways (e.g., process elements can be performed in other sequences). Therefore, it is to be understood that only the preferred embodiments and variations thereof have been shown and described, and that all changes and modifications that fall within the spirit of the present invention are desired to be protected.

[0089] For purposes of this disclosure, unless otherwise indicated, all numbers expressing quantities, sizes, dimensions, proportions, shapes, formulations, parameters, percentages, amounts, properties, and other numerical values ​​used in the specification and claims are to be understood as being modified in all instances by the term "about," even though the term "about" may not be expressly stated with the value, amount, or range. Thus, unless indicated to the contrary, the numerical parameters set forth herein are not, and need not be, precise and can be approximated and / or larger or smaller, as desired, to reflect tolerances, conversion factors, rounding, measurement errors, and the like, as well as other factors known to those of ordinary skill in the art, depending on the desired properties sought to be obtained by the subject matter of the present disclosure. For example, when referring to a value, the term "about" can be meant to encompass in some cases + / - 100%, in some cases + / - 50%, in some cases + / - 20%, in some cases + / - 10%, in some cases + / - 5%, in some cases + / - 1%, in some cases + / - 0.5%, and in some cases + / - 0.1% variation from the specified amount, as appropriate for practicing the disclosed methods.

[0090] Furthermore, the term "about," when used in connection with one or more numerical values ​​or numerical ranges, should be understood to refer to all such numerical values, including every numerical value within that range, and the recitation of numerical ranges by endpoints which modify that range by extending the upper and lower boundaries of the stated numerical values, includes all numbers contained within that range, for example, all integers including fractions thereof (e.g., a recitation of 1 to 5 includes 1, 2, 3, 4, and 5, as well as fractions thereof, e.g., 1.5, 2.25, 3.75, 4.1, etc.), and any range within that range.

Claims

1. 1. A method for determining a set physical orientation of an electronically steerable satellite antenna (120) for use in a satellite communications system, the method comprising: determining a position of the electronically steerable satellite antenna (120) relative to the Earth; receiving a signal (514), (516) from each of at least two different respective satellites (510), (512); determining a direction of incidence of each of the signals (514), (516) relative to a boresight direction (240) of the electronically steerable satellite antenna (120) by electronically steering a beam of the electronically steerable satellite antenna (120); calculating a set physical orientation of the electronically steerable satellite antenna (120) relative to the Earth based on the position of the electronically steerable satellite antenna (120) and the direction of incidence of each of the signals (514), (516) from the satellites (510), (512), where the satellites (510), (512) from which the signals (514), (516) are received are in known orbital positions relative to the Earth, and the set physical orientation includes a rotation of an azimuth angle (234), an elevation angle (232), and the boresight direction (240) of the electronically steerable satellite antenna (120) relative to the Earth; determining the direction of incidence of each of the signals (516) (514) relative to the boresight direction (240) of the electronically steerable satellite antenna (120) includes electronically steering the beam of the electronically steerable satellite antenna (120) to scan over a range of azimuth angles and a range of elevation angles.

2. 1. A method for mitigating interference between an electronically steerable satellite antenna (120) and a non-targeted satellite (112), the method comprising: determining a position of the electronically steerable satellite antenna (120) relative to the Earth; receiving a signal (514), (516) from each of at least two different respective satellites (510), (512); determining a direction of incidence of each of said signals (514), (516) relative to a boresight direction (240) of said electronically steerable satellite antenna (120) by electronically steering a beam of said electronically steerable satellite antenna (120); calculating a set physical orientation of the electronically steerable satellite antenna (120) relative to the Earth based on the position of the electronically steerable satellite antenna (120) and the direction of incidence of each of the signals (514), (516) from the satellites (510), (512), where the satellites (510), (512) from which the signals (514), (516) are received are in known orbital positions relative to the Earth, and the set physical orientation includes a rotation of an azimuth angle (234), an elevation angle (232), and the boresight direction (240) of the electronically steerable satellite antenna (120) relative to the Earth; determining a beam pattern projection profile of the electronically steerable satellite antenna (120); Associating the beam pattern emission profile with the set physical orientation of the electronically steerable satellite antenna (120); detecting an interference event based on the beam pattern emission profile of the electronically steerable satellite antenna (120) at the set physical orientation, the interference event including an emission from the electronically steerable satellite antenna (120) reaching a predetermined level relative to a non-target satellite (112); and modifying a transmission of the electronically steerable satellite antenna (120) in response to the interference event.

3. The method of claim 2 , wherein the beam pattern exit profile is asymmetric.

4. 4. The method of claim 2 or 3, further comprising steering the beam of the electronically steerable satellite antenna (120) to communicate a signal between the electronically steerable satellite antenna (120) and a target satellite (110).

5. The method of claim 4 , wherein the interference event is based on a side lobe (726a) emission separately from a main beam (722) emission of the beam pattern emission profile.

6. The method of claim 4 or 5, wherein the interference event relates to a geosynchronous orbit of a non-targeted satellite (712).

7. The method of claim 4 or 5, wherein the interference event concerns a non-targeted satellite (712) in low Earth orbit.

8. The method of any one of claims 1 to 7, wherein the electronically steerable satellite antenna (120) comprises a phased array satellite antenna (220).

9. 2. The method of claim 1, wherein the direction of incidence of each of the signals (514), (516) is determined based on signal strength indications of the signal for the range of azimuth angles and the range of elevation angles.

10. The method according to any one of claims 1 to 9, wherein at least one of the two different respective satellites (510), (512) comprises a geosynchronous satellite.

11. 11. The method of claim 1, wherein at least one of the two different respective satellites (510), (512) comprises a low Earth orbit satellite, and the known orbital position relative to the Earth is based on satellite orbit data of the low Earth orbit satellite at a time reference corresponding to reception of a signal from the low Earth orbit satellite.

12. A method according to any one of claims 1 to 11, wherein calculating the set physical orientation includes analyzing the azimuth angle (234), the elevation angle (232), and the rotation to within an error of approximately 1 degree or less.

13. A system operative to determine an orientation of an electronically steerable satellite antenna (120) for use in a satellite communications system, comprising: an electronically steerable satellite antenna (120) for electronically steering a beam of said electronically steerable satellite antenna (120) to receive signals (514), (516) from each of at least two different respective satellites (510), (512); a position module (314) for determining a position of the electronically steerable satellite antenna (120) relative to the Earth; an orientation calculation module (312) for determining a direction of incidence of each of the signals (514), (516) relative to a boresight direction (240) of the electronically steerable satellite antenna (120) given known orbital positions of the satellites (510), (512) relative to the Earth, and for calculating a set physical orientation of the electronically steerable satellite antenna (120) relative to the Earth based on the position of the electronically steerable satellite antenna (120) and the direction of incidence of each of the signals (514), (516), wherein the set physical orientation includes an azimuth angle (234), an elevation angle (232), and a rotation of the boresight direction (240) of the electronically steerable satellite antenna (120) relative to the Earth; The orientation calculation module (312) determines the direction of incidence of each of the signals (514), (516) relative to the boresight direction (240) of the electronically steerable satellite antenna (120) by electronically steering the beam of the electronically steerable satellite antenna (120) to scan through a range of azimuth angles and a range of elevation angles to identify the direction of incidence.

14. A system that operates to mitigate interference between an electronically steerable satellite antenna (120) and a non-targeted satellite (112), comprising: an electronically steerable satellite antenna (120) for electronically steering a beam of said electronically steerable satellite antenna (120) to receive signals (514), (516) from each of at least two different respective satellites (510), (512); a position module (314) for determining a position of the electronically steerable satellite antenna (120) relative to the Earth; an orientation calculation module (312) for determining a direction of incidence of each of the signals (514), (516) relative to a boresight direction (240) of the electronically steerable satellite antenna (120) given known orbital positions of the satellites (510), (512) relative to the Earth, and for calculating a set physical orientation of the electronically steerable satellite antenna (120) relative to the Earth based on the position of the electronically steerable satellite antenna (120) and the direction of incidence of each of the signals (514), (516), the set physical orientation including a rotation of an azimuth angle (234), an elevation angle (232), and the boresight direction (240) of the electronically steerable satellite antenna (120) relative to the Earth; an orientation calculation module (312) for associating a beam pattern projection profile with the set physical orientation of the electronically steerable satellite antenna (120); and a scheduler (330) for detecting an interference event based on the beam pattern emission profile of the electronically steerable satellite antenna (120) at the configured physical orientation, the interference event including an emission from the electronically steerable satellite antenna (120) reaching a predetermined level relative to the non-target satellite (112); The electronically steerable satellite antenna (120) modifies transmissions in response to the interference event; and a scheduler (330).

15. The system of claim 14 , wherein the beam pattern exit profile is asymmetric.

16. 15. The system of claim 14, wherein the electronically steerable satellite antenna steers the beam of the electronically steerable satellite antenna to communicate signals between the electronically steerable satellite antenna and a target satellite.

17. The system of claim 16, wherein the interference event is based on a side lobe (726a) emission separate from a main beam (722) emission of the beam pattern emission profile.

18. 18. The system of claim 16 or 17, wherein the interference event relates to a non-targeted satellite (712) in a geosynchronous orbit.

19. 18. The system of claim 16 or 17, wherein the interference event concerns a non-targeted satellite (712) in low Earth orbit.

20. The system of claim 19 , wherein the electronically steerable satellite antenna (120) comprises a phased array antenna (220).

21. 14. The system of claim 13, wherein the direction of incidence of each of the signals (514), (516) is determined based on signal strength indications of the signals (514), (516) for the range of azimuth angles and the range of elevation angles.

22. The system according to any one of claims 13 to 21, wherein at least one of the two different respective satellites (510), (512) comprises a geosynchronous satellite.

23. 22. The system of claim 13, wherein at least one of the two different respective satellites (510), (512) comprises a low Earth orbit satellite, and the known orbital position relative to the Earth is based on satellite orbit data of the low Earth orbit satellite at a reference time corresponding to reception of a signal from the low Earth orbit satellite.

24. The system of any one of claims 13 to 23, wherein the orientation calculation module (312) resolves the azimuth angle (234), the elevation angle (232), and the rotation to within an error of about 1 degree or less.

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