Ultra-low-cost high-performance satellite aperture

Abstract

The satellite antenna system may comprise an antenna receiver coupled to a plurality of flexible joints. Each joint may be fixed to one or more antenna elements. The joints may be deployed in space in an uncontrolled manner. Furthermore, the spacing between the joints, and therefore the spacing between the antenna elements, may be spaced apart in an uncontrolled manner. The antenna elements may not have pointing requirements. The antenna system may receive a training signal and associate the antenna elements with times of arrival based on the training signal. Upon receiving a data signal, the antenna system may apply coefficients determined from the association of the antenna elements with times of arrival to the data signal to find the desired signal coherence between the antenna elements.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This patent application claims the benefit of U.S. Provisional Patent Application No. 62 / 804,476, filed February 12, 2019, by PARKER et al., entitled “ULTRA-LOW COST HIGH PERFORMANCE SATELLITE-aPERTURE,” and to U.S. Provisional Patent Application No. 62 / 808,554, filed February 21, 2019, by PARKER et al., entitled “ULTRA-LOW COST HIGH PERFORMANCE SATELLITE-aPERTURE,” each of which is assigned to the assignee of this patent application and is expressly incorporated by reference in its entirety herein.

[0002] FIELD OF THEINVENTION The following relates generally to antenna systems, and more specifically to ultra-low cost, high performance satellite apertures. [Background technology]

[0003] Satellite systems use many different antenna types, each with specialized characteristics for a particular application. For example, a satellite may utilize a dish antenna to receive and transmit signals. A dish antenna may consist of a parabolic reflecting surface and a central feed horn. The parabolic surface facilitates the convergence of the incoming beam, which is reflected back to the central feed horn, located at the focus of the curvature. When the dish antenna receives a signal, the energy of the individual radio signals is combined, so the arriving signal is much stronger. Another example of an antenna is the Active Electronically Scanned Array (AESA). The AESA is a type of phased array antenna that can electronically steer a signal beam in any direction without physically moving the antenna. This antenna consists of an array of regularly spaced small antennas, each with a separate feed. The beam is electronically steered by controlling the phase of the radio waves transmitted and received by each of the multiple radiating elements in the antenna. This digitally controlled scanning nature of the AESA allows it to scan rapidly in any direction, compared to mechanically scanned radar, whose range is limited by the direction the AESA is pointing and the speed at which the AESA's motors can rotate the AESA. Summary of the Invention [Problem to be solved by the invention]

[0004] However, each antenna type has certain drawbacks that may not be suitable for all applications. For example, each antenna type has different size, mechanical complexity, power, cooling, weight, price, etc., which may determine which antenna should be used for a particular function. In some cases, an antenna that is less mechanically complex and less costly may be desirable.

[0005] The described technology relates to improved methods, systems, devices, and apparatus for ultra-low-cost, high-performance satellite apertures. The satellite's antenna system may consist of an antenna receiver coupled to a number of flexible joints. The joints may each be fixed to one or more antenna elements. The joints may be deployed in space in an uncontrolled manner. Furthermore, the spacing between the joints, and therefore between the antenna elements, may be spaced apart in an uncontrolled manner. The antenna elements may have no pointing requirements. The antenna system may receive a training signal and associate the antenna elements with times of arrival based on the training signal. Upon receiving a data signal, the antenna system may apply coefficients determined from the association of the antenna elements to times of arrival to the data signal in order to find the desired signal coherence between the antenna elements. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 illustrates an example of a system for wireless communication supporting an ultra-low-cost, high-performance satellite aperture in accordance with an embodiment of the present disclosure.

[0007] [Diagram 2] FIG. 2 illustrates an example of a satellite for wireless communications supporting an ultra-low-cost, high-performance satellite aperture in accordance with an embodiment of the present disclosure.

[0008] [Figure 3A] FIG. 3A illustrates an example of a satellite for wireless communications supporting an ultra-low-cost, high-performance satellite aperture in accordance with an embodiment of the present disclosure. [Figure 3B] FIG. 3B illustrates an example of a satellite for wireless communication supporting an ultra-low-cost, high-performance satellite aperture in accordance with an embodiment of the present disclosure.

[0009] [Figure 4] FIG. 4 illustrates an example of a satellite antenna for wireless communication supporting an ultra-low-cost, high-performance satellite aperture, in accordance with an embodiment of the present disclosure.

[0010] [Diagram 5]FIG. 5 illustrates a block diagram 500 of an apparatus 505 for ultra-low-cost, high-performance satellite aperture in accordance with an embodiment of the present disclosure.

[0011] [Figure 6] FIG. 6 illustrates a flowchart of a method 600 for supporting an ultra-low-cost, high-performance satellite aperture, according to an embodiment of the disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The described features generally relate to an antenna system, where each antenna element of the antenna system has an imprecise location in space. Each antenna element can be flexibly connected to an antenna receiver, and the couplings can be deployed in space in an uncontrolled manner. Upon receiving a data signal from a transmitter, the antenna system can apply linear algebra and multiple-input multiple-output (MIMO) signal processing to find signal energy coherence and coherently add all of the collected signal energies.

[0013] In contrast to other antenna systems, such as dish antenna systems, the present antenna system has low mechanical complexity and can be manufactured at low relative cost. For example, dish antennas can have narrow manufacturing tolerances to maintain signal energy coherence. Also, the high gain of the present system is comparable to that of dish antennas with very large diameters. Not only does the use of dish antennas with very large diameters increase manufacturing costs, but their use increases other costs, such as transportation and assembly costs, since the dish antennas must be transported into space and assembled. In addition, the directivity of the present antenna system can be configured differently than conventional antenna systems, reducing the mechanical complexity associated with antenna pointing.

[0014] This description provides examples, but is not intended to limit the scope, applicability, or configuration of embodiments of the principles described herein. On the contrary, the following description is intended to provide one of ordinary skill in the art with an enabling illustration for implementing embodiments of the principles described herein. Various changes may be made in the function and arrangement of each element.

[0015] Thus, various embodiments may omit, substitute, or add various procedures or components, as appropriate. For example, it should be understood that the methods may be performed in an order different from that described, and that various steps may be added, omitted, or combined. Also, aspects and elements described with respect to particular embodiments may be combined in various other embodiments. It should also be understood that the following systems, methods, and devices, separately or collectively, may be components of larger systems, and that other procedures may take precedence or be modified in their application.

[0016] FIG. 1 is a simplified diagram of a satellite communication system 100 illustrating the principles contained herein. The satellite communication system 100 may provide communication services over at least a portion of an area of ​​the Earth visible from the location of a satellite 105. The satellite 105 may be any suitable type of satellite, for example, a geostationary orbit (GEO), medium earth orbit (MEO), or low earth orbit (LEO). The satellite may provide communication services via user beams 145, each of which may provide coverage for a user beam coverage area. Although only a single user beam 145 is shown, the satellite 105 may be a multi-beam satellite that transmits multiple (e.g., typically 20-500, etc.) user beams 145, each of which may be directed toward a different region of the Earth. This allows for coverage of a relatively large geographic area and allows for frequency reuse within the covered area. Frequency reuse in a multi-beam satellite system may increase the capacity of the system for a given system bandwidth.

[0017] Each satellite beam 145 of the satellite 105 can support several user terminals 185. The user terminals 185 can receive data from the satellite 105 via an outbound downlink signal 155-b and transmit data via a return uplink signal 160-b. The user terminals 185 can be any two-way satellite fixed or mobile ground station, such as a very small aperture terminal (VSAT). Each satellite beam 145 can support other terminals, such as a multi-user access terminal 170, which can also be fixed or located on a moving platform 130, such as an aircraft, ship, vehicle, train, etc. As shown in FIG. 1, a satellite beam 145 assigned to a particular frequency range and polarization can carry an outbound downlink signal 155 or a return uplink signal 160 for both the fixed terminals 185 and the multi-user access terminals 170. The outgoing downlink signals 155 or return uplink signals 160 of the user terminals 185 and multi-user access terminals 170 may be multiplexed within the satellite beam 145 using multiplexing techniques such as time division multiple access (TDMA), frequency division multiple access (FDMA), multi-frequency time division multiple access (MF-TDMA), code division multiple access (CDMA), orthogonal frequency division multiple access (OFDMA), etc.

[0018] The satellite communication system 100 includes a gateway system 115 and a network 120 that may be connected to each other via one or more wired or wireless links. The gateway system 115 is configured to communicate with one or more user terminals 185 or multi-user access terminals 170 via satellites 105. The network 120 may include any suitable public or private network and may be connected to other communication networks (not shown), such as the Internet, a telecommunications network (e.g., the Public Switched Telephone Network (PSTN)), etc. The network 120 may connect the gateway system 115 with other gateway systems and may also communicate with the satellites 105 or other satellites. Alternatively, a separate network linking the gateways and other nodes may be used to cooperatively service user traffic. The gateway system 115 may also be configured to receive return signals (via the satellites 105) from the user terminals 185 or multi-user access terminals 170 that are directed to destinations in the network 120 or other communication networks.

[0019] The gateway system 115 may be a device or system that provides an interface between the network 120 and the satellite 105. The gateway system 115 may use the antenna 110 to transmit and receive signals to and from the satellite 105 via an outbound uplink signal 135 and a return downlink signal 140. The antenna 110 may be designed for bidirectional communication and with appropriate transmit power and receive sensitivity to reliably communicate with the satellite 105. In one embodiment, the satellite 105 is configured to receive signals from the antenna 110 in a particular frequency band and a particular polarization. Although shown as including one satellite 105, the satellite communication system 100 may include multiple satellites. The multiple satellites may have service coverage areas that at least partially overlap one another.

[0020] Each satellite user beam 145 of a satellite 105 supports (e.g., provides uplink and downlink resources for) user terminals 185 or multi-user access terminals 170 within its coverage area. Frequency reuse between satellite user beams 145 may be provided by assigning one or more frequency regions (which may be referred to as channels) to each satellite user beam 145 and / or through the use of orthogonal polarizations. A particular frequency region and / or polarization may be referred to as a "color," and frequency reuse in a tiled spot beam satellite system may be according to color.

[0021] The coverage of different satellite user beams 145 may be non-overlapping or may have various degrees of overlap, including 100% overlap. In one example, the satellite user beams 145 of a satellite 105 may be tiled and overlapping to provide complete or near complete coverage over a relatively large geographic area where the overlapping or adjacent beams use different frequency ranges and / or polarizations (e.g., different colors).

[0022] The satellite 105 can provide network access services to communication devices (e.g., computers, laptops, tablets, handsets, smart appliances) connected to user terminals 185 or communication devices 175 of passengers 180 on the mobile platform 130. For example, the passengers 180 can connect their communication devices 175 via wired (e.g., Ethernet) or wireless (e.g., WLAN) connections 176. The multi-user access terminals 170 can obtain network access services via user beams 145.

[0023] The multi-user access terminal 170 may use an antenna 165 mounted on the mobile platform 130 to communicate via outbound downlink signal 155-a and return uplink signal 160-a. When the multi-user access terminal 170 is located on a mobile platform, the antenna 165 may be mounted on an elevation and azimuth gimbal that points (e.g., actively tracks) the antenna 165 to the satellite 105. The satellite communication system 100 may operate in the International Telecommunications Union (ITU) Ku, K, or Ka bands (e.g., 17.7-21.2 gigahertz (GHz) for the downlink and 27.5-31 GHz for the uplink portion of the Ka band). Alternatively, the satellite communication system 100 may operate in other frequency bands, such as C-band, X-band, S-band, L-band, UHF, VHF, etc.

[0024] Those skilled in the art will appreciate that one or more aspects of the present disclosure may be implemented in system 100 to solve additional or alternative problems other than those described herein. Furthermore, aspects of the present disclosure may provide technical improvements over the "conventional" systems or processes described herein. However, the description and accompanying drawings include only exemplary technical improvements resulting from implementing aspects of the present disclosure, and therefore do not represent all of the technical improvements provided within the scope of the claims.

[0025] In one embodiment, the satellite 105 includes or is connected to an antenna system 101 that includes an antenna transceiver system coupled to a number of flexible joints. Each joint can connect a receiver to one or more antenna elements. The antenna transceiver system can have one or more transceivers. The antenna system 101 may be packaged for deployment of the satellite 105 in a compact configuration of flexible joints and antenna elements. Once the satellite 105 reaches a target orbit (e.g., LEO, MEO, GEO), the joints can be deployed in space to spread the antenna elements over a range for the aperture of the antenna system. The deployment position of each antenna element may not be predetermined or controlled during deployment. Thus, the spacing between the joints, and therefore the antenna elements, may not be predetermined prior to deployment and may be spaced apart in a manner that is not controlled by the physical characteristics of the flexible joints. The satellite 105 may have one or more features as described herein with respect to the disclosed antenna system 101.

[0026] After deployment, the antenna system 101 of the satellite 105 can receive training signals from various transmitting devices, such as the antenna 110, the user terminal 185, or the antenna 165. One or more antenna elements of the antenna system 101 can receive these training signals, and a processor of the antenna system 101 can determine location-related information, such as a time-of-arrival (TOA) parameter, and associate the TOA parameter with each antenna element. The antenna system 101 can further determine receiving coefficients based on the TOA parameters. Each coefficient may be based on a unique time of arrival signature (e.g., for each transceiver). The antenna system 101 can receive subsequent signals, such as data signals, from the antenna 110, the user terminal 185, or the antenna 165, and a processor of the antenna system 101 can utilize the coefficients to process the data signals. The transmitter that transmits the data signals may be the same or different from the transmitter that transmitted the training signals.

[0027] The antenna system 101 also allows frequency reuse between satellite user beams 145 to be obtained by unique weighting of arrival times between the end points of the satellite user beams 145 (the end points of the user beams are the satellites 101) and the terminals (e.g., antennas of the user terminals 185 or the multi-user access terminals 170). Because the weighting of arrival times is unique, the signal communications carried by the satellite user beams 145 can be uniquely separated from other satellite user beams (e.g., via linear algebra). For example, each user beam 145 may be associated with a different set of coefficients. Thus, the entire frequency assigned to each satellite user beam 145 can be reused by other satellite user beams without compromising or to a negligible extent the system communications performance. The uniqueness of the weighting of arrival times between the satellite user beams 145 and the end points can be determined by the diameter of the solid three-dimensional shape of the antenna system 101, the number of antenna elements of the antenna system 101, the separation between the user terminals, or a combination thereof.

[0028] Multiple satellite user beams 145 and signals associated with beams having the same frequency range can be received simultaneously and differentiated by weighting factors. The size of the volumetric shape and the number of elements determine the spatial or geographic resolution for distinguishing signals from different transmitters using different angles of arrival. This design can achieve resolutions in the range of 100 m to 1 km (e.g., about 1 km volumetric shape and 1,000 elements in a LEO configuration), and therefore can support very small effective user beams.

[0029] FIG. 2 illustrates an example of an antenna system 101-a for wireless communication supporting an ultra-low-cost, high-performance satellite aperture according to an embodiment of the present disclosure. The antenna system 101-a may include an antenna transmit / receive system 240, a branch 210, an antenna element 215, and a joint 220, which may be part of or connected to a satellite 105. The antenna system 101-a may be an example of an embodiment of the antenna system 101 of FIG. 1. The antenna system 101-a may be an example of an n-layer MIMO antenna. In some examples, the antenna system 101-a may be a two-layer MIMO antenna.

[0030] The antenna transmission / reception system 240 can receive signals such as training signals and data signals. The antenna transmission / reception system 240 can include multiple transceivers 235 and a processor 245. Each transceiver 235 can be connected to one or more antenna elements 215 (or leaf antennas) via a flexible joint 220. The flexible joints 220 can be made of flexible or semi-rigid materials (e.g., wire, coated wire, coaxial cable, twisted pairs of wire, shielded wire, conductive mechanical pivots, springs, rotors, gimbals, etc.). They are electrically connected to one or more antenna elements without restricting the deployment position of the one or more antenna elements 215 in each dimension. That is, the deployment position of the one or more antenna elements 215 may be limited by the position of the antenna elements along the flexible joint, but may not otherwise be limited in one or more spatial dimensions. In some cases, the uncontrolled deployment of the antenna elements 215 is within the flexibility of the flexible joints 220. In some examples, the antenna elements 215 may be attached to the flexible joints 220 via couplers, and in other examples, the antenna elements 215 may be attached directly to the flexible joints 220. The exact positioning of the antenna elements 215 is not controlled, but the spatial separation of the antenna elements may make mutual coupling insignificant. In some examples, the antenna system 101-a may include more than 100 or more than 1000 antenna elements 215.

[0031] The energy received by the antenna system 101-a may be proportional to the sum of the cross-sectional areas of the effective apertures of the antenna elements 215. The array gain of the antenna system 101-a may be the sum of the signal energy collected from the effective aperture of each antenna element 215. The gain of the antenna system 101-a may be expressed as: (Gain per antenna element) + 10log(number of antenna elements) The antenna elements 215 may be randomly oriented (e.g., spatial locations that are not predetermined or precisely controlled) and may feature large satellite aperture baselines. For example, the antenna elements 215 may feature baselines of greater than 100 meters, greater than 200 meters, greater than 500 meters, or greater than 1 kilometer. The antenna system 101-a may use various types of antenna elements 215 (e.g., dipole, biconic, monopole, patch), and each antenna element 215 may be of the same type, or the antenna system 101-a may use a combination of different types, as the case may be.

[0032] When deployed, the antenna elements 215 may form a volumetric shape. In some examples, at least one dimension of the volumetric shape may be greater than 100 times the wavelength distance of the data signal. In other examples, the orientation of the volumetric shape is not controlled relative to the satellite's orbital position, and in some cases the orientation of the satellite 105 or antenna system 101-a is not controlled during the orbit (e.g., the satellite 105 or antenna system 101-a may not use active attitude control). In some examples, the volumetric shape is approximately spherical, and signals transmitted from any angle and traversing the volumetric shape traverse a diameter 250 (e.g., at least a minimum diameter) of the volumetric shape.

[0033] The antenna system 101-a may have the same number of transceivers 235 as there are antenna elements 215. For example, each of the antenna elements 215 may be linked to its own transceiver 235 (e.g., each transceiver 235 may be connected to a single antenna element 215). Alternatively, the antenna system 101-a may have fewer transceivers 235 than there are antenna elements 215 (e.g., each transceiver 235 may be connected to multiple antenna elements 215).

[0034] In some examples, each of the antenna elements 215 may connect to the transceiver 235 via a series of branches 210 and leaves 220, with each branch 210 connected to one or more leaves 220, and each leaf 220 connected to one or more antenna elements 215. In some examples, the number of branches 210 may be the same as the number of transceivers 235. For example, at least a subset of the branches 210 may include multiple antenna elements 215, with each transceiver 235 connecting to one branch 210. The number of antenna elements 215 may be the same across all branches 210, or may be different to optimize the antenna array, or for power management, interference resistance, or failed antenna elements. Each branch 210 may include thermal management (e.g., heating elements), as well as power or amplification components. Each leaf 220 may connect one or more antenna elements 215 directly to the branch 210, or through a coupler (e.g., RF coupler). Each branch 210 may include components for pre-processing RF signals from the leaves 220 connected to the branch 210. For example, each branch 210 may include analog or digital processing components such as filters, low noise amplifiers, high power amplifiers, phase shifters, mixers, analog-to-digital converters, or other signal processing components. In some examples, each branch 210 includes analog weighting circuits (e.g., phase shifters, amplitude modulators) for applying analog beamforming weights to signals transmitted or received via the leaves 220 of the branch.

[0035] Each transceiver 235 may include components for RF communications (e.g., filters, low noise amplifiers, high power amplifiers, mixers, analog-to-digital converters, demodulators, or other signal processing components). For example, each transceiver 235 may include circuitry for MIMO processing, such as maximum ratio combining (MRC) of signals from each branch 210, leaf 220, or antenna element 215 to which it is connected.

[0036] Each branch 210 can be considered a sub-aperture of the overall synthetic aperture of the antenna system 101-a. Although not controlled to a predetermined distance, each branch 210 may be separated from each other by a branch distance 225, and each leaf 220 or antenna element 215 may be separated from each other by a leaf distance 230. Thus, although the branch distance 225 and leaf distance 230 are shown as average or minimum separable distances, the actual branch distances and leaf distances 230 between different branches 210 and leaves 220 may vary. The branch distance 225 or leaf distance 230 may provide sufficient separation between the branches or leaves so that the arrival times between the branches or leaves can be easily measured. For example, light travels 1 meter in 3.3 nanoseconds. Assuming 100 ns of discrimination between arrival times consistent with conventional digital logic processing, the branch distance 225 or leaf distance 230 may be approximately 30 meters. Assuming 10 ns of discrimination between arrival times consistent with conventional digital logic processing, the branch distance 225 or leaf distance 230 may be approximately 3 meters. The leaf distances 230 may be spaced apart by a sufficient distance to simplify the radiation pattern into a separate and independent collection of the base antenna element radiation pattern. For example, each branch may include leaves 220 or antenna elements 215 spaced apart along its length by the leaf distances 230, and the arrival time of each leaf 220 may be identified (assuming a relatively low turn-back or loop-back of the branches 210). In some cases, some antenna elements 215 may have leaf distances 230 less than the minimum distance for identification. If antenna elements 215 with less than the minimum leaf distance for identification are connected with different transceivers 235 (e.g., via different branches 210), the signals may be identified via the different transceivers. If the antenna elements 215 are connected with the same transceiver 235, the coefficients may be combined or the signals may be suppressed to reduce the effect of the composite signal of the antenna elements 215 without being identified.

[0037] In some cases, the leaf distance 230 or the branch distance 225 may be maintained using a mechanical device. For example, a semi-rigid member (not shown) may be connected at a location along the branch 210 and may provide a separation force tending to hold the branches 210 apart from one another. The member may be foldable or encapsulable to allow packaging for launch and orbital insertion of the satellite 105. In other examples, the leaf 220 or the branch 210 may be connected to an expandable structure (e.g., a balloon) that expands upon deployment. In other examples, a heavy object coupled to the end of the branch 210 may be ejected from the satellite 105 (e.g., via a spring) and a flexible joint (e.g., a wire) of the branch may be stretched from the satellite 105 to a desired extension. In yet other examples, the mechanical force for maintaining the branch distance 225 or the leaf distance 230 may result from centrifugal forces during deployment or operation. For example, the satellite 105 may be launched into orbit while rotating or may use an attitude adjustment mechanism to establish rotation, and the centrifugal force from the rotation can help maintain the leaf distance 230 or branch distance 225.

[0038] In addition to pneumatic (expansion), spring, and centrifugal forces, additional examples for deploying the leaves 220 or branches 210 and forming the separation of the leaf distance 230 or branch distance 225 include mechanical ratchets or pawls, chemical reactions that may change and harden the structure after deployment to maintain or guide the leaf distance 230 and branch distance 225, electrostatic forces that attract or repel the leaves 220 and branches 210, or thermal expansion of the mechanical structure connecting the leaves 220 and branches 210. In some cases, small reactive jets, pyrotechnic devices, or ion thrusters can be used to deploy, maintain, or guide the leaf distance 230 and branch distance 225 (e.g., to maintain a minimum distance without strictly controlling the position). Any combination or individual selection of these methods can be used.

[0039] In one example of a combination of these methods, a large array of patch antennas can be assembled as leaves 220 covering all 4Pi steradians on an inflatable ball that also serves as a ground plane. These patch antenna leaves 220 can be connected via flexible connectors to branches 210 that are individually connected back to the satellite 105 (e.g., to the transceiver 235). Upon deployment, a spring force can be used to eject the branches 210 containing the uninflated patch antennas outward. Once deployment is reached, a chemical reaction can be used to harden the branches 210 and leaves 220 containing the inflatable ball of patch antennas (which can be pyrotechnically inflated using air pressure to complete the deployment).

[0040] In a second example of how these methods can be combined, a large array of biconical antennas can be assembled as biconical antenna leaves 220 and can include mechanical springs that assume the appropriate shape upon release from restraints. These biconical antenna leaves 220 can be connected via flexible connectors to branches 210 that are individually connected back to the satellite 105. During deployment, air pressure can be used to expand the branches 210, thereby extending them outward while simultaneously releasing the biconical antenna leaves 220 from their restraints so that the spring forces force each leaf 220 into a predetermined shape. Once deployment is reached, a chemical reaction can be used to harden the expanded branches to complete the deployment.

[0041] In a third example of how these methods can be combined, a large array of dipole antennas can be assembled as leaves 220 and can include mechanical springs that assume a predetermined shape when released from a restraining constraint. These dipole antenna leaves 220 can be connected via flexible connectors to branches 210 that are individually connected back to the satellite 105. During deployment, the spring forces can be used to launch the branches 210 outward, thereby releasing the dipole antenna leaves 220 from their restraining constraints and allowing the spring forces to force each leaf 220 into a predetermined shape. An electrostatic force can be applied to each branch 210 and each leaf 220 of like charge to repel each leaf 220 and branch 210 from each other to complete the deployment.

[0042] In a fourth example of how these methods can be combined, a large array of mixed antenna types of leaves consisting of monopole and patch antennas can be assembled as leaves 220. The leaves 220 can use spring tension to maintain their shape and can cover all 4Pi steradians on a ball that can also serve as a ground plane. These monopole and patch antenna leaves 220 can be connected via flexible connectors to branches 210 that are individually connected back to the satellite 105. Upon deployment, the spring force can be used to launch the branches 210 outward, which releases the monopole and patch antenna leaves 220 from their restraining constraints and allows the spring force to force each leaf 220 into the appropriate shape. In conjunction with the initial spring force to launch the branches 210 outward, thermal energy received from the sun can be irradiated onto each branch 210, causing the material of each branch to expand and forcing the mechanical network of ratchets and pawls to lock into place, forcing the deployment of each leaf 220 and branch 210 to be completed.

[0043] The interference tolerance within the linear dynamic range of the antenna system 101-a is managed via the MIMO selection of the data signals. The interference tolerance (dynamic range compression) is managed by the ratio of the number of antenna elements 215 required to close the link between the terrestrial user terminal and the satellite 105 to the total number of antenna elements 215.

[0044] 3A illustrates an example of a signal reception technique 300 for wireless communication supporting ultra-low-cost, high-performance satellite apertures, in accordance with an embodiment of the present disclosure. In some examples, the antenna element 305 may implement an embodiment of the antenna element 215 described in FIG.

[0045] A transmitting device, such as an antenna 110 and / or a user terminal 185, may transmit training signals 310 to the antenna elements 305 before transmitting a data signal 315. The training signals (e.g., 310-a, 310-b, ... 310-n) may arrive at the antenna elements 305 sequentially or in any overlapping order. In some examples, the training signals 310 are received at the antenna elements 305 simultaneously (e.g., over the same frequency) (e.g., at least partially overlapping in time) when the training signals 310 arrive from locations separated by a minimum spatial or geographic resolution (e.g., in the range of 100 m to 1 km). The training signals 310 generally include a sequence that is known a priori to the satellite 105. The training signals 310 may be encrypted to authenticate and ensure that the training signals 310 from valid user terminals are processed. In some examples, the training signals 310 are orthogonal sequences.

[0046] The training signal 310 may also convey additional information (e.g., by use of multiple available sequences). In some examples, the training signal 310 may include location information of the user terminal. For example, the user terminal may know its location (e.g., via GPS or other geographic location signals) and in some cases may indicate a code associated with its location in the training signal 310. In one example, each user beam is associated with a different code, and the user terminal may determine which beam serves the user terminal (e.g., using location information and stored beam coverage area information, or using received signals indicating the user beam). The user terminal may then select (e.g., randomly) the code associated with the beam, or one of a group of codes associated with the beam. In some cases, the information may include a priority of the communication. For example, a user may have a priority or may select between multiple priorities based on the type of data for communication. In other examples, the training signal 310 may include information such as user terminal type, user type, etc. In some examples, the same transmitting device may transmit the training signal 310 and the data signal 315. In other examples, the transmitting device transmitting the training signal 310 may be different from the transmitting device transmitting the data signal 315. If the channel and the distance from a particular antenna element 305 to a transmitting device change periodically due to the antenna elements 305 shifting in space or changing attitude (e.g., without attitude control during orbit), the antenna system 101 may continuously or periodically receive the training signal 310 for proper channel tracking.

[0047] A transceiver (e.g., transceiver 235) may receive training signals 310-a from one or more antenna elements 305 (e.g., antenna element 305-a, antenna element 305-b, antenna element 305-n). A training processor (e.g., processor 245) of the antenna system 101 may receive signals from each antenna element 305 (e.g., from one or more transceivers) and determine the arrival time of each of the antenna elements 305 based on the received training signals 310-a. A beam weighting processor (e.g., processor 245) of the antenna system 101 may determine a coefficient for each determined arrival time. Thereafter, one or more transceivers may receive the data transmission 315-a received at the antenna element 305. The beam weighting processor may then combine the received data signal from each antenna element 305 with the respective determined coefficients associated with each antenna element 305 to decode the data signal 315-a. For example, the beam weighting processor may combine signals according to the determined coefficients using maximum ratio combining (MRC). In some cases, the beam weighting processor may generate signals for transmission from one or more antenna elements 305 based on the determined coefficients.

[0048] In one example, the transceiver may receive a training signal associated with each data signal. For example, the transceiver may receive a training signal 310-b received at each antenna element 305 from the same or different transmitters and determine the arrival time of each of the multiple antenna elements 305 based on the received training signal 310-b. The beam weighting processor may then update the previously determined coefficients (associated with the training signal 310-a) with newly determined coefficients from the arrival time data associated with the training signal 310-b for receiving the data signal 315-b. Each additional data signal (e.g., data signal 315-n) may be preceded by a training signal (e.g., training signal 310-n).

[0049] In another example, the training processor can determine time-of-arrival information based on multiple training signals (e.g., training signals 310-a and 310-b) received from known locations and determine spatial information for each antenna element 305. Using the spatial information, the beam weighting processor can determine the time-of-arrival (e.g., eigenmode) of each antenna element for a data transmission 315 from a known location (which may be the same as one of the known locations of the training signals or may be a different location). The beam weighting processor can then combine the received data transmission from each antenna element 305 with the respective determined coefficients associated with each antenna element 305 to decode the data transmission 315.

[0050] As mentioned above, the antenna elements 305 may be associated with branches, each of which may have multiple antenna elements 305 and may include circuitry for pre-processing the signals. In some examples, determining the coefficients of each training signal 310 associated with the data signal 315 may be performed on a branch-by-branch basis. For example, the antenna elements 305 on each branch may be characterized or calibrated based on training signals from one or more sources (e.g., at least two physically separated transmitters), and the branch's circuitry (e.g., analog weighting circuitry) may combine the signals received by the branch's elements 305 into a composite branch signal. The transceiver may then receive the training signals associated with each data signal and determine the arrival times of each composite branch signal from each branch based on the training signals. The beam weighting processor may then determine the coefficients based on the determined arrival times associated with the training signals for receiving the data signals. In some cases, the arrival times associated with the branches may be used to modify the weights applied to each branch. For example, the relative positions of each leaf and the orientation of the training signals determined from the arrival times may be characterized to modify the weights used for the leaves of the branch (e.g., for the associated data signals). A coefficient can be applied to each branch for transmission of the signal based on the determined arrival time, and a circuit in each branch (e.g., an analog weighting circuit) can apply a weighting to each leaf for the signal to be transmitted.

[0051] 3B illustrates an example of a signal reception technique 350 for wireless communication supporting ultra-low-cost, high-performance satellite apertures, in accordance with aspects of the present disclosure. In some examples, antenna system 101-b may implement aspects of antenna system 101 described in FIG. 1 and antenna system 101-a described in FIG.

[0052] The uncorrelated energy 360 may represent a vector associated with the uncorrelated signals received via each antenna element 305 of the antenna system 101-b. The beam weighting processor may combine the uncorrelated signals of the uncorrelated energy 360 according to coefficients determined from one or more training signals 310 to generate the correlated energy 355. The total amplitude and power of the correlated energy 355 may be calculated as follows:

number

[0053] where n is the total number of branches and k is the total number of leaves of antenna system 101-b. The total amplitude and power of the uncorrelated energy 360 can be calculated as follows:

number

[0054] where n is the total number of branches and k is the total number of leaves of the antenna system 101-b. The signal to noise ratio can be calculated as follows:

number

[0055] Here, the uncorrelated noise power increases linearly and the correlated signal power increases squarely.

[0056] 4 illustrates an example of an antenna system 400 for wireless communications supporting ultra-low-cost, high-performance satellite apertures, according to an embodiment of the present disclosure. The antenna system 400 may include an antenna system 101-c, a dish 405, and an emitter 410. In some examples, the antenna system 101-c may implement aspects of the antenna system 101 described in FIG. 1, the antenna system 101-a described in FIG. 2, and the antenna system 101-b described in FIG. 3B. The antenna system 400 may be referred to as a hybrid dish / MIMO antenna system.

[0057] The dish 405 may represent a dish that is not perfectly parabolic. An advantage of a dish 405 that is not perfectly parabolic is that it may have looser manufacturing requirements compared to a conventional parabolic dish, potentially reducing manufacturing and realization costs. The dish 405 may also be larger than parabolic dishes manufactured to tolerances typically used in satellite communications. For example, a typical large parabolic dish for satellite communications may be about 5 meters to 15 meters in diameter. In some cases, the dish 405 may be significantly larger than a typical large parabolic dish for satellite communications, such as having a diameter of 30 meters, 50 meters, 100 meters, or more. The dish may be folded for launch of the satellite 105 and may expand to a deployed shape in various ways. For example, the dish 405 may be formed by a conductive coating on a balloon that is expanded when the antenna system 400 is deployed into orbit. Alternatively, the deployment of the dish 405 may be similar to the deployment of a solar sail. Further alternatively, the dish 405 may be constructed of multiple rigid elements and may expand upon deployment.

[0058] The radio wave 415 may be received by the dish 405 in the RF wavefront from the transmitter and reflected from the dish 405 to form a dispersion focal region. The antenna system 101-c and its associated antenna elements may be at least partially within the dispersion focal region of the formed dish 405. In some examples, the dish 405 may increase the RF flux power density to the antenna system 101-c, and the antenna array of the antenna system 101-c may be realized such that a significant portion of the RF flux is captured by the antenna system 101-c. The efficiency of the dish 405 may be calculated by taking the flux power transferred to the antenna system 101-c and dividing it by the flux power collected by the antenna system 101-c.

[0059] As described above, training signals from a transmitter can be used to generate coefficients for receiving or transmitting signals from antenna elements of antenna system 400. However, determining the coefficients can include measuring dish imperfections and the location of the antenna element. For example, a signal received at a given antenna element of antenna system 101-c may be reflected non-coherently from multiple locations on the dish, and the dish imperfections can be measured and combined with antenna element time of arrival information to determine the coefficients for coherently receiving the signal.

[0060] Additionally or alternatively, one or more auxiliary satellites 410 can be used to synthesize the positions of the antenna elements of the antenna system 101-c. For example, one or more auxiliary satellites 410 can be positioned at known positions relative to the antenna system 400 and can transmit signals that are measured by the antenna system 400 (e.g., to determine the antenna vectors of each element of the antenna system 101-c). The known positions of the transmitters can be used to measure dish imperfections and synthesize times of arrival or antenna element coefficients in combination with or without receiving training signals from the transmitters of the data signals.

[0061] 5 illustrates a block diagram 500 of an apparatus 505 for ultra-low-cost, high-performance satellite aperture according to an embodiment of the present disclosure. In some examples, the apparatus 505 may be an example of an embodiment of the antenna system 101 of FIGS. 1, 2, 3B, and 4. The apparatus 505 may include a receiver 510, a training processor 515, a beam weighting processor 520, and a transmitter 525. The components may communicate via one or more buses.

[0062] The device 505 and / or at least some of its various subcomponents may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software executed by a processor, at least some of the functions of the device 505 and / or its various subcomponents may be performed by a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device designed to perform the functions described in this disclosure, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The device 505 and / or at least some of its various subcomponents may be physically located in different locations, including being distributed such that some of the functions are implemented in one or more physical devices at different physical locations. In some examples, the device 505 and / or at least some of its various subcomponents may be separate and distinct components according to various aspects of the present disclosure. In other examples, the apparatus 505 and / or at least some of its various subcomponents may be combined with one or more other hardware components, including, but not limited to, an I / O component, a transceiver, a network server, another computing device, one or more other components described in this disclosure, or combinations thereof, in accordance with various aspects of the disclosure.

[0063] The receiver 510 may receive information, such as packets and user data. The information may be passed to other components of the device 505. The receiver 510 may include multiple receive chains, each of which may include circuitry for processing a received RF signal (e.g., amplifiers, mixers, analog-to-digital converters, demodulators). Each receive chain of the receiver 510 may include circuitry for coherently combining energy from multiple antennas (e.g., MRC circuitry).

[0064] The training processor 515 may receive signals from the antenna receiver associated with one or more training signals from the transmitter. Each of the multiple antenna elements may also be associated with a respective time of arrival based at least in part on the one or more training signals. The training processor 515 may also determine the respective time of arrival vectors based at least in part on the location of the transmitter and the respective times of the time of arrival vectors. The one or more training signals may include an indication of location information associated with the transmitter, an indication of a user beam for the transmitter, a priority of communication from the transmitter, or a combination thereof. The training processor 515 may be configured to decode the one or more first signals to obtain the one or more training signals and validate the one or more training signals based on the decoding.

[0065] The beam weighting processor 520 may combine one or more signals associated with a data signal received from the transmitter via the receiver according to a number of coefficients determined based at least in part on an association between the number of antenna elements and their respective times of arrival, may update the number of coefficients based at least in part on the respective second times of arrival, and may generate one or more signals for transmission to the target receiver based at least in part on the number of coefficients determined based at least in part on an association between the number of antenna elements and their respective times of arrival.

[0066] The training processor 515 and the beam weighting processor 520 may be examples of processors that may include intelligent hardware devices (e.g., general purpose processors, DSPs, central processing units (CPUs), microcontrollers, ASICs, FPGAs, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, the processor may be configured to operate the memory array using a memory controller. In other cases, the memory controller may be integrated into the processor. The processor may be configured to execute computer-readable instructions stored in memory to perform various functions.

[0067] The transmitter 525 can transmit signals generated by other components of the device 505. The transmitter 525 can include multiple transmitter chains, each of which can include circuitry (e.g., modulators, digital-to-analog converters, mixers, amplifiers) for processing digital signals to generate RF signals for transmission. In some examples, the transmitter 525 can be collocated with the receiver 510 in a transceiver (which can include, e.g., multiple receive / transmit chains).

[0068] FIG. 6 illustrates a flow chart of a method 600 for supporting an ultra-low-cost, high-performance satellite aperture, according to an embodiment of the present disclosure. The operations of method 600 may be implemented by an antenna system or components thereof, as described herein. For example, the operations of method 600 may be performed by an antenna system, as described with reference to FIGS. 1-5. In some embodiments, the antenna system may execute a set of instructions that control functional elements of a communication session distribution system to perform functions described herein. Additionally or alternatively, the communication session distribution system may perform aspects of the functions described herein using dedicated hardware.

[0069] At 605, the antenna system may receive one or more training signals from the first transmitter via the antenna receiver. The one or more training signals may include an indication of location information associated with the first transmitter, an indication of a user beam for the first transmitter, a priority for communications from the first transmitter, or a combination thereof. In some examples, the one or more training signals may be encrypted (e.g., according to a public key associated with a user terminal, a user beam, a user group, a terminal type, a user type, or a combination thereof). Receiving the training signals may include decrypting the training signals (e.g., according to a private key corresponding to the public key). The operations of 605 may be performed according to methods described herein. In some examples, aspects of the operations of 605 may be performed by a training processor as described with reference to FIG. 5.

[0070] At 610, the antenna system may associate a time of arrival with each antenna element based on the received one or more training signals. The operations of 610 may be performed according to methods described herein. In some examples, aspects of the operations of 610 may be performed by a training processor, as described with reference to FIG.

[0071] At 615, the antenna system may receive one or more data signals from the second transmitter via the antenna receiver. In some examples, the second transmitter may be the same as the first transmitter. In other examples, the second transmitter may be different from the first transmitter. The operations of 615 may be performed according to methods described herein. In some examples, aspects of the operations of 615 may be performed by a beam weighting processor, as described with reference to FIG. 5.

[0072] At 620, the antenna system may combine one or more data signals according to coefficients determined by the multiple antenna elements of the antenna system and their respective arrival times. The operations of 620 may be performed according to methods described herein. In some examples, aspects of the operations of 620 may be performed by a beam weighting processor, as described with reference to FIG.

[0073] It should be noted that the methods described herein illustrate possible implementations, and that the acts and steps may be rearranged or modified, and other implementations are possible. Additionally, aspects of two or more methods may be combined.

[0074] The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, the data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0075] The various example blocks and modules described in connection with the disclosure herein may be implemented or performed by a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of these designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0076] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software executed by a processor, the functions may be stored or transmitted as one or more instructions or codes on a computer-readable medium. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of the software, the functions herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Also, features implementing the functions may be physically located in various locations, including being distributed such that some of the functions are implemented in different physical locations.

[0077] As used herein, including the claims, "or" when used in a list of items (e.g., a list of items preceded by phrases such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Also, as used herein, the phrase "based on" should not be construed as referring to an exclusive set of conditions. For example, an exemplary process described as "based on condition A" may be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" is to be construed in the same manner as the phrase "based at least in part on."

[0078] In the accompanying drawings, similar components or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash symbol and a second label that distinguishes between the similar components. If only a first reference number is used herein, the description is applicable to any one of the similar components having the same first reference number, regardless of the second reference number or other subsequent reference numbers.

[0079] The description set forth herein describes exemplary configurations in conjunction with the accompanying drawings and does not represent every example that may be implemented or fall within the scope of the claims. The term "exemplary" as used herein means "serving as an example, instance, or illustration" and does not mean "preferred" or "advantageous over other examples." The detailed description includes specific details for the purpose of providing an understanding of the described technology. However, these techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described embodiments.

[0080] The description herein is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure should not be limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An antenna system (101) for a satellite (105), comprising: An antenna receiver (240); a plurality of antenna elements (215) coupled to the antenna receiver (240) via a plurality of flexible joints (220), the deployed positions of the plurality of antenna elements (215) being limited by their positions along their respective flexible joints (220) and not otherwise limited in one or more spatial dimensions; a training processor (515) configured to receive, via the antenna receiver (240), one or more first signals associated with one or more training signals (310) transmitted from a first transmitter (110, 170, 185), and to associate each of the plurality of antenna elements (215) with a respective first time of arrival of the one or more training signals (310); a beam weighting processor (520) configured to combine a plurality of second signals associated with a data signal (315) received via the antenna receiver (240) from a second transmitter (110, 170, 185) according to a plurality of coefficients determined based at least in part on an association between the plurality of antenna elements (215) and the respective first times of arrival; An antenna system (101) comprising:

2. 2. The antenna system (101) of claim 1, further comprising a reflector configured to reflect radio waves into a dispersion focal region, the plurality of antenna elements being at least partially within the dispersion focal region.

3. The antenna system (101) of claim 1 or 2, wherein the plurality of antenna elements (215) form a volumetric shape.

4. The antenna system (101) of claim 3, wherein at least one dimension of said contour is greater than 100 times the wavelength of said one or more second signals.

5. 5. The antenna system (101) of claim 3 or 4, wherein the orientation of the volumetric shape of the plurality of antenna elements (215) relative to the orbital position of the satellite is not restricted in one or more spatial dimensions.

6. 6. The antenna system (101) of claim 1, wherein the antenna receiver (240) comprises a plurality of receive chains (235), the number of the receive chains (235) of the antenna receiver (240) being less than the number of the plurality of antenna elements (215).

7. 6. The antenna system (101) of claim 1, wherein the antenna receiver (240) comprises a plurality of receive chains (235), and each of the plurality of antenna elements (215) is associated with a different one of the plurality of receive chains (235).

8. The antenna system (101) of any one of claims 1 to 7, wherein the second transmitter (110, 170, 185) is the same as the first transmitter (110, 170, 185).

9. The antenna system (101) of any one of claims 1 to 7, wherein the second transmitter (110, 170, 185) is different from the first transmitter (110, 170, 185).

10. the training processor (515) is further configured to receive one or more third signals from the antenna receiver (240), where the one or more third signals are associated with a second training signal (310) transmitted by a third transmitter (110, 170, 185), and to associate each of the plurality of antenna elements (215) with a respective second time of arrival of the one or more third signals; 10. The antenna system (101) of claim 1, wherein the beam weighting processor (520) is further configured to update the coefficients for each of the second arrival times.

11. 11. The antenna system (101) of claim 1, wherein the beam weighting processor (520) is configured to generate one or more third signals for transmission from the plurality of antenna elements (215) to a target receiver based at least in part on a second plurality of coefficients determined based at least in part on an association between the plurality of antenna elements (215) and the respective first arrival times.

12. 10. The antenna system of claim 1, wherein the training processor is further configured to receive one or more third signals from the antenna receiver, the one or more third signals being associated with a second training signal transmitted by a third transmitter, associate each of the plurality of antenna elements with a respective second time of arrival based at least in part on the second training signal, and determine spatial information for each of the plurality of antenna elements at the respective first time of arrival and the respective second time of arrival.

13. The antenna system (101) of claim 12, wherein the training processor (515) is further configured to determine the plurality of coefficients of the spatial information and the position of the second transmitter (110, 170, 185).

14. 14. The antenna system (101) of claim 1, wherein the one or more training signals (310) include an indication of location information associated with the first transmitter (110, 170, 185), an indication of a user beam for the first transmitter (110, 170, 185), an indication of a priority for communication from the first transmitter (110, 170, 185) defined by a user, or a combination thereof.

15. 15. The antenna system of claim 1, wherein the training processor is configured to decode the one or more first signals to obtain the one or more training signals and to verify the one or more training signals based on the decoding.

16. A method for receiving radio waves by an antenna system (101) of a satellite (105), comprising the steps of: receiving one or more first signals using a plurality of antenna elements (215), the one or more first signals corresponding to a training signal (310) transmitted by a first transmitter, the plurality of antenna elements (215) each coupled to one of a plurality of flexible joints (220), the deployed positions of the plurality of antenna elements (215) being limited by their positions along their respective flexible joints (220) and not otherwise limited in one or more spatial dimensions; associating each of the plurality of antenna elements (215) with a first time of arrival of a respective one of the one or more first signals; receiving a plurality of second signals using the plurality of antenna elements (215), the plurality of second signals corresponding to a data signal (315) transmitted by a second transmitter; combining the plurality of second signals according to a plurality of coefficients determined based at least in part on associations between the plurality of antenna elements (215) and the respective first times of arrival; The method includes:

17. The method of claim 16 , wherein the plurality of antenna elements (215) form a solid shape.

18. The method of claim 17 , wherein at least one dimension of the feature is greater than 100 times the wavelength of the plurality of second signals.

19. 19. The method of claim 17 or 18, wherein the orientation of the volumetric shape of the plurality of antenna elements (215) relative to the orbital position of the satellite (105) is not restricted in one or more spatial dimensions.

20. 20. The method of claim 16, wherein the steps of receiving the one or more first signals and receiving the plurality of second signals comprise receiving the one or more first signals and the plurality of second signals via a plurality of receive chains (235).

21. 21. The method of claim 20, wherein the number of the plurality of receive chains (235) is less than the number of the plurality of antenna elements (215).

22. 21. The method of claim 20, wherein each of the plurality of antenna elements (215) is associated with a different one of the plurality of receive chains (235).

23. 23. The method of any one of claims 16 to 22, wherein the second transmitter (110, 170, 185) is the same as the first transmitter (110, 170, 185).

24. 23. The method of any one of claims 16 to 22, wherein the second transmitter (110, 170, 185) is different from the first transmitter (110, 170, 185).

25. receiving one or more third signals using the plurality of antenna elements (215), the one or more third signals being associated with one or more second training signals (310) from a third transmitter (110, 170, 185); associating each of the plurality of antenna elements (215) with a second time of arrival of a respective one or more third signals; updating the coefficients for each of the second arrival times; 25. The method of any one of claims 16 to 24, further comprising:

26. generating one or more third signals for transmission from the plurality of antenna elements to a target receiver (110, 170, 185) based at least in part on a second plurality of coefficients determined based at least in part on an association between the plurality of antenna elements (215) and the respective first times of arrival; transmitting the one or more third signals from the plurality of antenna elements (215); 26. The method of any one of claims 16 to 25, further comprising:

27. A method for transmitting a second training signal from an antenna receiver, the second training signal being associated with a third training signal transmitted by a third transmitter. associating each of the plurality of antenna elements (215) with a respective second time of arrival based at least in part on the second training signal; determining spatial information for each of the plurality of antenna elements (215) for the respective first time of arrival and the respective second time of arrival; 25. The method of any one of claims 16 to 24, further comprising:

28. determining said plurality of coefficients of said spatial information and the position of said second transmitter (110, 170, 185); 30. The method of claim 27, further comprising:

29. 29. The method of claim 16, wherein the training signal includes an indication of location information associated with the first transmitter, an indication of a user beam for the first transmitter, an indication of a priority for communication from the first transmitter as defined by a user, or a combination thereof.

30. decoding the one or more first signals to obtain the training signal (310); verifying the training signal (310) based on the decoding; 30. The method of any one of claims 16 to 29, further comprising:

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