Beamforming and block coding with three orthogonal axis element antenna

Abstract

Methods, systems, and devices for beamforming and block coding with three orthogonal axis element antenna are described. A system may include a plurality of access nodes that receive composite return signals that include orthogonal component fields and a composite of return data signals transmitted from a plurality of user terminals and relayed by the wireless relay. Each of the plurality of access nodes may include an antenna with at least three elements oriented to capture the respective orthogonal component fields of the composite return signals and a receiver that receives the respective composite return signal from the wireless relay via the antenna. The system may include a distribution network that obtains the composite return signals and a return beamformer coupled with the distribution network, and a return decoder that performs decoding of information of the return data signals across the respective return component beam field signals.

Description

BEAMFORMING AND BLOCK CODING WITH THREE ORTHOGONAL AXIS ELEMENT ANTENNACROSS REFERENCE

[0001] The present Application for Patent claims the benefit of U.S. Provisional Patent Application No. 63 / 580,559 by Robinson, et al. entitled “SMALL-SIGNAL CENTRIC SCALABLE, MASSIVE SIGNAL PROCESSING GAIN ARCHITECTURE” filed September 5, 2023, assigned to the assignee hereof, and expressly incorporated by reference herein.BACKGROUND

[0002] The following relates generally to communications, including beamforming and block coding with three orthogonal axis element antenna.

[0003] Communications devices may communicate with one another using wired connections, wireless (e.g., radio frequency (RF)) connections, or both. Wireless communications between devices may be performed using a wireless spectrum that has been designated for a service provider, wireless technology, or both. In some examples, the amount of information that can be communicated via a wireless communications network is based on an amount of wireless spectrum designated to the service provider, and an amount of frequency reuse within the region in which service is provided. Satellite communications may use beamforming to establish beams to increase frequency reuse, however, providing a high level of frequency reuse in satellite communication systems employing beamforming presents challenges.SUMMARY

[0004] The described techniques relate to improved methods, systems, devices, and apparatuses that support beamforming and block coding with three orthogonal axis element antenna. For example, the described techniques provide for various systems and implementations, such as the following.

[0005] A system for providing a communication service to user terminals distributed over a service area via a wireless relay comprising multiple return receive / transmit signal paths for providing a communication service to user terminals distributed over a service area via a wireless relay comprising multiple return receive / transmit signal paths is described. Thesystem for providing a communication service to user terminals distributed over a service area via a wireless relay comprising multiple return receive / transmit signal paths may include one or more memories storing processor executable code, and one or more processors coupled with the one or more memories. The one or more processors may individually or collectively be operable to execute the code to cause the system for providing a communication service to user terminals distributed over a service area via a wireless relay comprising multiple return receive / transmit signal paths to a plurality of access nodes at distributed locations, wherein communications between the user terminals and the distributed locations via the wireless relay are subject to near- field communication effects at a carrier frequency of the communications, and wherein the plurality of access nodes receive respective composite return signals, each of the respective composite return signals comprising up to three respective orthogonal component fields and a composite of return data signals transmitted from a plurality of the user terminals and relayed by the wireless relay, each of the plurality of access nodes comprising, an antenna with at least three elements oriented to capture the respective orthogonal component fields of the composite return signals, a receiver that receives the respective composite return signal from the wireless relay via the antenna, the respective composite return signal comprising respective component signals associated with the respective orthogonal component fields, a distribution network that obtains the respective composite return signals from the plurality of access nodes, wherein the distribution network corrects the respective composite return signals for the near field communication effects, timing and phase for respective path delays and phase shifts between the wireless relay and the plurality of access nodes, a return beamformer coupled with the distribution network, the return beamformer comprising a matrix multiplier that obtains respective return component beam field signals associated with each of the respective orthogonal component fields for a return user beam coverage area based on a matrix product of a return beam weight matrix and a vector of the respective composite return signals, and a return decoder that performs decoding of information of the return data signals across the respective return component beam field signals.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 shows an example of a satellite communications system that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples described herein.

[0007] FIG. 2 shows an example of an end-to-end beamforming system that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples described herein.

[0008] FIG. 3 shows an example of an antenna scheme that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0009] FIG. 4 shows an example of a signal path model that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0010] FIG. 5 shows an example of a multipath channel scheme that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0011] FIG. 6 shows an example of a signal path model that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0012] FIG. 7 shows an example of a multipath channel scheme that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0013] FIG. 8 shows an example of a satellite that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0014] FIG. 9 shows an example of a ground segment scheme that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.

[0015] FIG. 10 shows an example of a beamformer scheme that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein.DETAILED DESCRIPTION

[0016] In some communications scenarios, communications may occur between different devices at different locations (e.g., on Earth’s surface, in Earth’s atmosphere, in space, or anycombination thereof). Further, some communications systems (e.g., satellite communications systems or other communication systems that may communicate over great distances) may operate in the far field. As such, limiting the system to plane wave communication techniques (e.g., including polarizations such as horizontal (H), vertical (V), left hand circular polarization (LHCP), or right hand circular polarization (RHCP) may be considered to be efficient. However, the geometry of some systems (e.g., aperture sizes or distributions of cooperating antennas) may result in the effect that communications (even those over distances such as those involved in satellite communications) may be subject to near field effects. In addition, antennas, devices, or vehicles may change position or orientation, possibly affecting communications quality and reliability. Such problems are further compounded by some antennas or antenna elements that may not take advantage of available energy for communication, be it transmission or reception of communications.

[0017] To reduce or eliminate such concerns, an antenna that includes multiple elements, such as a tripole antenna, that may allow the antenna to take advantage of multiple orthogonal polarizations for communications. For example, a tripole antenna may allow for reception or transmission of communications that utilize three orthogonal polarizations for communications. Further, the use of such an antenna may allow for the use of block codes across the multiple antenna elements (e.g., a single code across multiple signals of multiple antenna elements or multiple individual codes applied to individual signals of individual antenna elements), such as space-time block codes or turbo codes, that may allow for increased communications capacity and quality.

[0018] Aspects of the disclosure are described with reference to a satellite communications system, an end-to-end beamforming system, an antenna scheme, a signal path model, a link scheme, a multipath channel scheme, a signal path model, a link scheme, a multipath channel scheme, a satellite, a ground segment scheme, and a beamformer scheme. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, block diagrams, and flowcharts that relate to beamforming and block coding with three orthogonal axis element antenna.

[0019] FIG. 1 shows depicts a satellite communications system 100. The satellite serves as an example of a wireless relay. Any other wireless relay may be used and would operate in a similar fashion. This remains true throughout the remainder of the present disclosure. The system 100 comprises a ground-based Earth station 101 , a communication satellite 103, and an Earth transmission source, such as a user terminal 105. A satellite coverage area may bebroadly defined as that area from which, and / or to which, either an Earth transmission source, or an Earth receiver, such as a ground-based Earth station or a user terminal, can communicate through the satellite. In some systems, the coverage area for each link (e.g., forward uplink coverage area, forward downlink coverage area, return uplink coverage area, and return downlink coverage area) can be different. The forward uplink coverage area and return uplink coverage area are collectively referred to as the uplink satellite coverage area. Similarly, the forward downlink coverage area and the return downlink coverage area are collectively referred to as the downlink satellite coverage area. While the satellite coverage area is only active for a satellite that is in service (e.g., in a service orbit), the payload of the satellite has a payload antenna pattern that is independent of the relative location of the satellite with respect to the Earth. That is, the payload antenna pattern is a pattern of distribution of energy transmitted from an antenna of a payload (either transmitted from or received by the antenna of the payload). The payload antenna pattern illuminates (transmits to or receives from) a particular satellite coverage area when the satellite is in a service orbit. The antenna coverage area is defined by the payload antenna pattern, the orbital position and attitude for which the satellite is designed, and a given antenna gain threshold. In general, the intersection of an antenna pattern (at a particular effective antenna gain, e.g., 3 dB, 4 dB, 6 dB 10 dB from peak gain) with a particular physical region of interest (e.g., an area on or near the earth surface) defines the coverage area for the antenna. Antennas can be designed to provide a particular antenna pattern (and / or coverage area) and such antenna patterns can be determined computationally (e.g., by analysis or simulation) and / or measured experimentally (e.g., on an antenna test range or in actual use).

[0020] While only one user terminal 105 is shown in the figure for the sake of simplicity, there are typically many user terminals 105 in the system. The satellite communications system 100 operates as a point to multi-point system. That is, the Earth station 101 within the satellite coverage area can send to and receive information from any of the user terminals 105 within the satellite coverage area. However, the user terminals only communicate with the Earth station 101. The Earth station 101 receives forward data from a communication network 107, modulates the data using a feeder link modem 109 and transmits the data to the satellite 103 on a forward feeder uplink 111. The satellite 103 relays this forward data to user terminals 105 on the forward user downlink (sometimes called a forward service downlink) 113. In some cases, the forward direction communication from the Earth station 101 is intended for several of the user terminals 105 (e.g., information is multicast or broadcast tothe user terminals 105). In some cases, the forward communication from the Earth station 101 is intended for only one user terminal 105 (e.g., unicast to a particular user terminal 105). The user terminals 105 transmit return data to the satellite 103 on a return user uplink (sometimes called a return service uplink) 115. The satellite relays that return data to the Earth station 101 on a return feeder downlink 117 (sometimes called a return service downlink). A feeder- link modem 109 demodulates the return data, which is forwarded on to the communication network 107. This return-link capability is generally shared by a number of user terminals 105.

[0021] FIG. 2 shows an example end-to-end beamforming system 200. The end-to-end beamforming system 200 includes: a ground segment 202; an end-to-end relay 203; and a plurality of user terminals 217. The ground segment 202 comprises M space segment Access Nodes (ANs) 215, spread geographically over an AN area. The ANs 215 cooperate in transmitting forward uplink signals 221 to form user beams and return downlink signals 227 are collectively processed to recover return uplink signals 225. A set of ANs 215 that are within a distinct (e.g., geographically separated or otherwise orthogonally configured) AN area and cooperate to perform end-to-end beamforming for forward and / or return user beams is referred to herein as an “AN cluster.” In some examples, multiple AN clusters in different AN areas may also cooperate. AN clusters may also be referred to as “AN farms” or “SAN farms.” ANs 215 and user terminals 217 can be collectively referred to as Earth receivers, Earth transmitters, or Earth transceivers, depending upon the particular functionality at issue, since they are located on, or near, the Earth and both transmit and receive signals. In some cases, user terminals 217 and / or ANs 215 can be located in aircraft, watercraft or mounted on landcraft, etc. In some cases, the user terminals 217 can be geographically distributed. The ANs 215 can be geographically distributed. The ANs 215 exchange signals with a CPS 205 within the ground segment 202 via a distribution network 218 . The CPS 205 is connected to a data source (not shown), such as, for example, the internet, a video headend or other such entity.

[0022] User terminals 217 may be grouped with other nearby user terminals 217 (e.g., as illustrated by user terminals 217a and 217b). In some cases, such groups of user terminals 217 are serviced by the same user beam and so reside within the same geographic forward and / or return user beam coverage area 219. A user terminal 217 is within a user beam if the user terminal 217 is within the coverage area serviced by that user beam. While only one such user beam coverage area 219 is shown in FIG. 2 to have more than one user terminal 217, in somecases, a user beam coverage area 219 can have any suitable number of user terminals 217. Furthermore, the depiction in FIG. 2 is not intended to indicate the relative size of different user beam coverage areas 219. That is, the user beam coverage areas 219 may all be approximately the same size. Alternatively, the user beam coverage areas 219 may be of varying sizes, with some user beam coverage areas 219 much larger than others. In some cases, the number of ANs 215 is not equal to the number of user beam coverage areas 219.

[0023] The end-to-end relay 203 relays signals wirelessly between the user terminals 217 and a number of network access nodes, such as the ANs 215 shown in FIG. 2. The end-to-end relay 203 has a plurality of signal paths. For example, each signal path can include at least one receive antenna element, at least one transmit antenna element, and at least one transponder (as is discussed in detail below). In some cases, the plurality of receive antenna elements are arranged to receive signals reflected by a receive reflector to form a receive antenna array. In some cases, the plurality of transmit antenna elements is arranged to transmit signals and thus to form a transmit antenna array.

[0024] In some cases, the end-to-end relay 203 is provided on a satellite. In other cases, the end-to-end relay 203 is provided on an aircraft, blimp, tower, underwater structure or any other suitable structure or vehicle in which an end-to-end relay 203 can reside. In some cases, the system uses different frequency ranges (in the same or different frequency bands) for the uplinks and downlinks. In some cases, the feeder links and user links are in different frequency ranges. In some cases, the end-to-end relay 203 acts as a passive or active reflector.

[0025] As described herein, various features of the end-to-end relay 203 enable end-to- end beamforming. One feature is that the end-to-end relay 203 includes multiple transponders that, in the context of end-to-end beamforming systems, induce multipath between the ANs 215 and the user terminals 217. Another feature is that the antennas (e.g., one or more antenna subsystems) of the end-to-end relay 203 contribute to end-to-end beamforming, so that forward and / or return user beams are formed when properly beam-weighted signals are communicated through the multipath induced by the end-to-end relay 203. For example, during forward communications, each of multiple transponders receives a respective superposed composite of (beam weighted) forward uplink signals 221 from multiple (e.g., all) of the ANs 215 (referred to herein as composite input forward signals), and the transponders output corresponding composite signals (referred to herein as forward downlink signals). Each of the forward downlink signals can be a unique composite of the beam- weighted forward uplink signals 221, which, when transmitted by the transmit antenna elements of theend-to-end relay 203, superpose to form the user beams in desired locations (e.g., recovery locations within forward user beams, in this case). Return end-to-end beamforming is similarly enabled. Thus, the end-to-end relay 203 can cause multiple superpositions to occur, thereby enabling end-to-end beamforming over induced multipath channels. In some examples, once the induced multipath communications are established, the communications bearing the induced multipath characteristics may be “transported” or communicated to another device or devices via one or more communication links (e.g., a laser optical link or other communication link) in a point to point manner (e.g., as opposed to a multipath or multi-point manner).

[0026] In some examples, the end-to-end relay may include one or more antennas, such as the antenna 245. The antenna 245 may include one or more elements, which may be of any type of antenna element. For example, the antenna 245 may include dipole elements, hoop elements, one or more other types of antenna elements, or any combination thereof. Further, the elements of the antenna 245 may be arranged in any manner. For example, in the case of dipole elements being used, the antenna elements of the antenna 245 may be arranged with a common origin or the elements may be spread apart. Further, in some examples, the antenna 245 may be a half-tripole, which may be arranged with a monopole and a ground plane in place of one or more of the elements of a tripole antenna.

[0027] Though the antenna 245 is described and depicted as being included in the end-to- end relay 203, the antenna 245 may equally be used with the ANs 215, the user terminals 217, one or more other devices, or any combination thereof, either alone or in conjunction with such antennas 245 at the end-to-end relay 203. Further, the advantages described with respect to the antenna 245 of the end-to-end relay 203 are equally applicable to the ANs 215, the user terminals 217, one or more other devices, or any combination thereof (again, either alone or in conjunction with such antennas 245 at the end-to-end relay 203). Additionally, or alternatively, some devices may employ the use of the antennas 245 and other devices may employ other types or configurations of antennas 245.

[0028] The CPS 205 may include a plurality of feeder link modems 207. For the forward link, the feeder link modems 207 each receive forward user data streams 209 from various data sources, such as the internet, a video headend (not shown), etc. The received forward user data streams 209 are modulated by the modems 207 into K forward beam signals 211. In some cases, K may be in the range of 1 , 2, 4, 8, 16, 32, 64, 128, 256, 212, 1024 or numbers in-between or greater. Each of the K forward beam signals carries forward user data streamsto be transmitted on one of K forward user beams. Accordingly, if K = 400, then there are 400 forward beam signals 211, each to be transmitted over an associated one of 400 forward user beams to a forward user beam coverage area 219. The K forward beam signals 211 are coupled with a forward beamformer.

[0029] If M ANs 215 are present in the ground segment 202, then the output of the forward beamformer is M access node-specific forward signals 216, each comprising weighted forward beam signals corresponding to some or all of the K forward beam signals 211. Each of the ANs 215 may include an antenna 245 supporting multiple polarizations, and thus each of the M access node-specific forward signals 216 may include multiple component signals corresponding to the multiple polarizations, generated by applying polarization coding. The forward beamformer may generate the M access node-specific forward signals216 based on a matrix product of the K x M forward beam weight matrix with the K forward data signals, where each element of the forward beam weight matrix is a vector of coefficients for the multiple polarizations (e.g., beam weights may be applied separately for each polarization component). A distribution network 218 distributes each of the M access nodespecific forward signals to a corresponding one of the M ANs 215. Each AN 215 transmits a forward uplink signal 221 including components for each antenna element based on a respective access node-specific forward signal 216. Each AN 215 transmits its respective forward uplink signal 221 for relay to one or more (e.g., up to and including all) of the forward user beam coverage areas via one or more (e.g., up to and including all) of the forward receive / transmit signal paths of the end-to-end relay. Transponders 410 within the end-to-end relay 203 receive a composite input forward signal comprising a superposition of forward uplink signals 221 transmitted by a plurality (e.g., up to and including all) of the ANs 215. Each transponder (e.g., each receive / transmit signal path through the relay) relays the composite input forward signal as a respective forward downlink signal to the user terminals217 over the forward downlink.

[0030] In some examples, the ANs 215 may receive composite return signals 208. The return data signal from user terminals 217 may be included in multiple (e.g., up to and including all) of the composite return signals 208. In some examples, a beam weight generator may generates a K x M return beam weight matrix and a return beamformer may calculates K return beam signals, where each matrix element of the return beam weight matrix is a vector of coefficients for the multiple polarizations. For example, this calculation can be based on a matrix product of a return beam weight matrix and a vector of therespective composite return signals 208. Further, a beam signal interface 224 may include a return beam signal demodulator and a return beam data de-multiplexer. The return beam signal demodulator may apply return polarization coding across the polarization components of the K return beam signals to demodulate each of the return beam signals to obtain K return beam data streams associated with the K return user beam coverage areas. Return beam data de-multiplexer may de-multiplex each of the K return beam data streams into respective return user data streams associated with the return data signals transmitted from user terminals 217.

[0031] In some examples, the ANs 215, the user terminals 217, or both, may be distributed (e.g., across the surface of the Earth, in Earth’s atmosphere, or in space), such as on the scale of hundreds or thousands of kilometers between the different ANs 215. As such, the end-to-end beamforming system 200 may therefore be subject to one or more near field effects to which communications involving the ANs 215 may be subject. Such near field effects may be present due to the geometry of and distances between the ANs 215. In some examples, the distributed ANs 215 may act as a phased array and near field effects may be present in communications scenarios involving the distributed ANs 215. In some examples, the ANs 215 may form at least a portion of a very large baseline array. In some examples, the near field effects may be associated with a dimension over which the ANs 215 are distributed, which may be related to a Fraunhofer distance. For example, in some cases, if the effective distance over which the communications travel is less than the Fraunhofer distance, near field effects may be present, and if the effective distance is greater than the Fraunhofer distance, far field effects may be present. However, in some cases, there may not be a hard boundary or border (e.g., of distances) between situations in which near field effects are present and a situation in which far field effects are present.

[0032] In some examples, different types of wave fronts or wave front affects (e.g., spherical or planar) may be present in communications of the system. For example, in some cases, given a relatively small aperture in space (e.g., associated with the end-to-end relay) planar wave front effects may be present for communications. However, for communications of the end-to-end beamforming system 200 from the end-to-end relay 203 to the ANs 215, communications may be subject to spherical wave front effects, such as in scenarios involving communications from the end-to-end relay 203 to the ANs 215. Similarly, spherical wave front effects may also be present in communications from the ANs 215 to the end-to-end relay 203. In some examples, the end-to-end relay 203 may echo or relay suchcommunications to the user terminals 217, in which case such communications may involve spherical wave front effects, as the source transmissions that are being relayed may already inherently include time delays that result from spherical wavefront effects. As such, the spherical wavefront effects that result from the arrangement of the ANs 215 may be considered to be reciprocal between elements of the end-to-end beamforming system 200. In some cases, depending on whether spherical wave front effects and / or planar wave front effects are present, different calculations or techniques (e.g., any of the techniques described herein) may be applied. For example, if a spherical wave or effects thereof are present, calculations or techniques based on planar waves or effects thereof may be incomplete. Similarly, if a planer wave or effects thereof are present, then spherical calculations or spherical technique may be incomplete or include extraneous processing.

[0033] In some examples, closed loop monitoring and closed loop adjustments to one or more communication parameters may be employed. For example, if the end-to-end beamforming system 200 has an initially low error rate for a given set of beam weights, the error rate may increase over time as the system “drifts” away from the initial beam weight set. In some examples, the closed-loop controller compensates for this drift which regains the low error rate. Further, in some examples,, the closed-loop controller may require periodic channel sounding using known transmissions (e.g., to act as training data). In some examples, the closed loop monitoring may be supported by the calibration support module 424 and the satellite beacon generator 426 depicted in FIG. 10.

[0034] For example, the phase shifts induced by feeder links can be removed (e.g., prior to beamforming). The phase shift of each of the links between the end-to-end relay and the M ANs 215 will be different. The causes for different phase shifts for each link include, but are not limited to, the propagation path length, atmospheric conditions such as scintillation, Doppler frequency shift, and different AN 215 oscillator errors. These phase shifts are generally different for each AN 215 and are time varying (due to scintillation, Doppler shift, and difference in the AN 215 oscillator errors). By removing dynamic feeder link impairments, the rate at which beam weights adapt may be slower than an alternative where the beam weights adapt fast enough to track the dynamics of the feeder link.

[0035] In the return direction, feeder downlink impairments to an AN 215 are common to both the relay PN beacons and user data signals (e.g., return downlink signals). In some cases, coherent demodulation of the relay PN beacon provides channel information that is used to remove most or all of these impairments from the return data signal. In some cases, the relayPN beacon signal is a known PN sequence that is continually transmitted and located in-band with the communications data. The equivalent (or effective) isotropically radiated power (EIRP) of this in-band PN signal is set such that the interference to the communications data is not larger than a maximum acceptable level. In some examples, the satellite beacon generator 426 depicted in FIG. 10 may transmit the beacon.

[0036] In some cases, a feeder link impairment removal process for the return link involves coherent demodulation and tracking of the received timing and phase of the relay PN beacon signal. For example, a relay beacon signal demodulator may determine receive timing and phase adjustments to compensate for feeder link impairment based on comparing the relay PN beacon signal with a local reference signal (e.g., local oscillator or PEE). The recovered timing and phase differences are then removed from the return downlink signal (e.g., by a receive timing and phase adjuster), hence removing feeder link impairments from the communications signal (e.g., return downlink signals 227). After feeder link impairment removal, the return link signals from a beam will have a common frequency error at all ANs and thus be suitable for beamforming. The common frequency error may include, but is not limited to, contributions from the user terminal frequency error, user terminal uplink Doppler, end-to-end relay frequency translation frequency error and relay PN beacon frequency error.

[0037] In the forward direction, the access node beacon signal from each AN may be used to help remove feeder uplink impairments. The feeder uplink impairments will be imposed upon the forward link communications data (e.g., the access node-specific signal) as well as the access node beacon signal. Coherent demodulation of the access node beacon signal may be used to recover the timing and phase differences of the access node beacon signal (e.g., relative to the relay beacon signal). The recovered timing and phase differences are then removed from the transmitted access node beacon signal such that the access node beacon signal arrives in phase with the relay beacon signal.

[0038] In some cases, the forward feeder link removal process is a phase locked loop (PLL) with the path delay from the AN to the end-to-end relay and back within the loop structure. In some cases, the round-trip delay from the AN to the end-to-end relay and back to the AN can be significant. For example, a geosynchronous satellite functioning as an end-to- end relay will generate round-trip delay of approximately 250 milliseconds (ms). To keep this loop stable in the presence of the large delay, a very low loop bandwidth can be used. For a 250 ms delay, the PLL closed loop bandwidth may typically be less than one Hz. In suchcases, high-stability oscillators may be used on both the satellite and the AN to maintain reliable phase lock.

[0039] In some cases, the access node beacon signal is a burst signal that is transmitted during calibration intervals. During the calibration interval, communications data is not transmitted to eliminate this interference to the access node beacon signal. Since no communications data is transmitted during the calibration interval, the transmitted power of the access node beacon signal can be large, as compared to what would be required if it were broadcast during communication data. This is because there is no concern of causing interference with the communications data (the communications data is not present at this time). This technique enables a strong signal-to-noise ratio (SNR) for the access node beacon signal when it is transmitted during the calibration interval. The frequency of occurrence of the calibration intervals is the reciprocal of the elapsed time between calibration intervals. Since each calibration interval provides a sample of the phase to the PLL, this calibration frequency is the sample rate of this discrete time PLL. In some cases, the sample rate is high enough to support the closed loop bandwidth of the PLL with an insignificant amount of aliasing. The product of the calibration frequency (loop sample rate) and the calibration interval represents the fraction of time the end-to-end relay cannot be used for communications data without additional interference from the channel sounding probe signal. In some cases, values of less than 0. 1 are used and in some cases, values of less than 0.01 are used.

[0040] In some examples, the multiple ANs 215 may be considered to act as a rake filter. For example, in the course of communications, the multiple ANs 215 may each receive information and elements of information of the multiple ANs 215 may be compared to other elements of the information based on the relative positions of the different ANs 215. The differences in such information may be described as the array effect, as each AN 215 may receive different information due to the different locations of the ANs 215 (particularly in scenarios in which the ANs 215 are spread across large distances, such as hundreds or thousands of kilometers). For example, the signal across the multiple ANs 215 may be relatively similar, but may include time delays or differences across the multiple ANs 215. Further, in some examples, the signals across multiple antenna elements of the antennas 245 may be processed in a similar manner. This may result in additional elements in a channel matrix that may account for different signals received along different paths and in different polarizations. Further, additional processing (e.g., any operations described herein) may alsotake advantage of these multiple polarizations, communication locations, or other elements to improve signal quality, reliability, strength, one or more other communication characteristics, or any combination thereof.

[0041] In some cases, forward and return calibration may be performed to calibrate relative Euler angles of the ANs 215 to one or more user terminals 217. For example, ANs 215 may perform calibration for forward and return signals to establish a vector of weights to apply to signals received at the multiple antenna elements of the antennas 245 from the one or more user terminals 217 to recover the orthogonal polarization fields transmitted by the one or more user terminals 217.

[0042] FIG. 3 shows an example of an antenna scheme 300 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The antenna 310 may be an example of the antenna 245.

[0043] In some examples, the antenna 310 includes three elements, and the three elements may be arranged such that each element is orthogonal to each other element in three dimensional space. By arranging the elements in such a way, the orientation of the end-to-end relay 203, the orientation of the user terminals 217, may not affect the total amount of polarization energy received at the end-to-end relay 203, even in the presence of near field effects. For example, as each of the antenna elements is orthogonal to the others, in combination, the three antenna elements may capture substantially all of the polarization energy of transmissions communicated by the end-to-end relay 203. For example, the element 315-a may be associated with an X polarization 320-a, the element 315-b may be associated with a Y polarization 320-b, and element 315-c may be associated with a Z polarization 320-c. However, it should be noted that each element may not always be associated with the same polarization as the antenna 310, a device associated with the antenna 310, or another device communicating with the device associated with the antenna 310 may move, and the relative polarizations of signals may change. The polarizations 320 are only examples to show that the antenna 310 is capable of transducing a greater amount of energy of a signal (e.g., all energy of a signal) as compared to other approaches, regardless of the particular polarization of the signal. Additionally, or alternatively, the antenna 310 may be sensitive to signaling that is of any polarization in three dimensional space, as the elements 315 are all oriented orthogonal to one another, thereby capturing all possible polarizations.

[0044] In the end-to-end beamforming system 200, return path communications from a user terminal 217 may be transmitted as follows. First, beam field signals (e.g., of 1, 2, or 3 simultaneous polarizations) may originate in in an orthogonal coordinate system of x, y, and z as defined at the user terminal. These beam field signals then propagate to the end-to-end relay 203 and are received using the orientation of x, y, and z of the end-to-end relay 203. As a result, the captured signal may be considered to be of a net Euler angle between the userterminal x, y, z coordinate system and the receiving antenna elements x, y, z coordinate system.

[0045] By using the antenna 310 (e.g., where the antenna 310 is a tripole antenna), it may be the case that the orthogonal three axis energy capture allows the communication system to compensate for any relative Euler angles (e.g., between the antenna 310 and one or more other antennas of other elements of a system, such as the ANs 215, the user terminals 217, or both). For example, because the antenna 10 is capable of receiving energy across all polarizations in three dimensional space, the Euler angle between the antenna 310 and other antenna elements is of less importance, as energy that would otherwise be lost due to Euler angles may simply be captured by a different element 315 of the antenna 310. Further, a device using the antenna 310 may also effectively select between different Euler angles by selecting different elements 315 or combinations of elements 315 to use for communications, which, individually, may be associated with different Euler angles between the individual elements 315 and an antenna of another device.

[0046] In some examples, the end-to-end beamforming system 200 may take advantage of block coding, such as space-time block codes or turbo block codes, for communications involving the end-to-end relay 203. Coding across orthogonal polarizations using space-time block codes or turbo block codes may generally be referred to as polarization coding. For example, space-time block codes may involve the use of multiple repetitions of signaling being transmitted with both spatial and temporal diversity. For example, multiple copies of a data stream may be encoded in blocks and space-time block coded across the different polarizations (e.g., across the different elements 315). As the antenna 310 is capable of receiving signals of different polarizations (e.g., across the different elements 315), the use of a space-time block code or turbo code (or other code) may be advantageous, as different elements 315 may receive different spatial repetitions of signaling. Additionally, or alternatively, as turbo codes may make use of multiple decoders and difference reconciliation between these decoders, they may also be applicable to communications using the antenna310, as these multiple encoded streams may be received or associated with multiple elements 315 of the antenna 310. Additionally, or alternatively, multiple individual codes (e.g., multiple individual turbo codes) may be employed. For example, each element 315 may be associated with a different individual turbo code. In some cases, a calibration procedure may be performed to determine if respective communication links can be established for the different polarizations (e.g., a quantity of the different polarizations for which the communication links can be closed, or determined to maintain orthogonality and have sufficient SNR to be used for the polarization coding).

[0047] In some examples, coding, decoding, beam weighting, and any other procedure or operation described herein may be made across the multiple polarizations, such as the X polarization 320-a, the Y polarization 320-b, and the Z polarization 320-c. For example, in a situation involving an arrangement of the elements 315 that do not share a common origin, different beam weights may be applied to signals received at multiple elements 315. In some examples, a sub-beam weight may be applied to one or more signals of the multiple elements to adjust for any effects resulting from differing polarizations of the elements 315. The subbeam weights may be determined at each of the transmitter or receiver based on a calibration procedure.

[0048] In some examples, the antenna 310 of any of the devices described herein may communicate a composite signal that may include or be associated with one or more of the polarizations 320, including the X polarization 320-a, the Y polarization 320-b, and the Z polarization 320-c (which are only examples of possible polarizations). However, in some cases the composite signal may include a single polarization (e.g., such as right hand circular polarization (RHCP), or left hand circular polarization (LHCP)), two polarizations (e.g., Vertical-Elliptical or Horizontal-Elliptical), or three polarizations (e.g., Vertical-Elliptical, Horizontal-Elliptical, and Lateral-Elliptical).

[0049] In those examples in which a single polarization is employed, this may result in a single data stream being communicated. If two polarizations are used, two separate data streams may be communicated, and the use of three polarizations may result in three separate data streams. In any case, each data stream may be associated with a respective link-margin. Thus, with a given constraint on transmit power per data stream, it is possible to increase data transmission up to three times the data rate (e.g., using three polarizations) obtained with a given system transmit power (e.g., a maximum system transmit power) so long as the link closes for each data stream independently.

[0050] FIG. 4 shows an example of a signal path model 400 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The signal path model 400 may be an example model of signal paths for signals carrying return data on the end-to-end return link, where a quantity of polarizations supported may be up to P. Return data is the data that flows from user terminals 217 to the ANs 215. Signals in FIG. 6 flow from right to left. The signals originate with user terminals 217. The user terminals 217 transmit return uplink signals 225 (which have return user data streams) up to the end-to-end relay 203, where each return uplink signal 225 includes P polarization components. Return uplink signals 225 from user terminals 217 in K user beam coverage areas 219 are received by an array of L x P receive / transmit signal paths 1702. In some cases, an uplink coverage area for the end-to-end relay 203 is defined by that set of points from which all of the L receive antenna elements 406 can receive signals. In other cases, the relay coverage area is defined by that set of points from which a subset (e.g., a desired number more than 1, but less than all) of the L receive antenna elements 406 can receive signals. Similarly, in some cases, the downlink coverage area is defined by the set of points to which all of the L transmit antenna elements 409 can reliably send signals. In other cases, the downlink coverage area for the end-to-end relay 203 is defined as that set of points to which a subset of the transmit antenna elements 409 can reliably send signals. In some cases, the size of the subset of either receive antenna elements 406 or transmit antenna elements 409 is at least four. In other cases, the size of the subset is 6, 10, 20, 100, or any other number that provides the desired system performance.

[0051] For the sake of simplicity, some examples are described and / or illustrated as all L receive antenna elements 406 receiving signals from all points in the uplink coverage area and / or all L transmit antenna elements 409 transmitting to all points in the downlink coverage area. Such descriptions are not intended to require that all L elements receive and / or transmit signals at a significant signal level. For example, in some cases, a subset of the L receive antenna elements 406 receives an uplink signal (e.g., a return uplink signal 225 from a user terminal 217, or a forward uplink signal 221 from an AN 215), such that the subset of receive antenna elements 406 receives the uplink signal at a signal level that is close to a peak received signal level of the uplink signal (e.g., not substantially less than the signal level corresponding to the uplink signal having the highest signal level); others of the L receive antenna elements 406 that are not in the subset receive the uplink signal at an appreciably lower level (e.g., far below the peak received signal level of the uplink signal). In some cases,the uplink signal received by each receive antenna element of a subset is at a signal level within 10 dB of a maximum signal level received by any of the receive antenna elements 406. In some cases, the subset includes at least 10% of the receive antenna elements 406. In some cases, the subset includes at least 10 receive antenna elements 406.

[0052] Similarly, on the transmit side, a subset of the L transmit antenna elements 409 transmits a downlink signal to an Earth receiver (e.g., a return downlink signal 227 to an AN 215, or a forward downlink signal 222 to a user terminal 217), such that the subset of transmit antenna elements 409 transmits the downlink signal to the receiver with a received signal level that is close to a peak transmitted signal level of the downlink signal (e.g., not substantially less than the signal level corresponding to the downlink signal having the highest received signal level); others of the L transmit antenna elements 409 that are not in the subset transmit the downlink signal such that it is received at an appreciably lower level (e.g., far below the peak transmitted signal level of the downlink signal). In some cases, the signal level is within 3 dB of a signal level corresponding to a peak gain of the transmit antenna element 409. In other cases, the signal level is within 6 dB of the signal level corresponding to a peak gain of the transmit antenna element 409. In yet other cases, the signal level is within 10 dB of the signal level corresponding to a peak gain of the transmit antenna element 409.

[0053] As shown in FIG. 4 and discussed in greater detail below, in some cases, a receive / transmit signal path 1702 comprises a receive antenna element 406, a transponder group 411, and a transmit antenna element 409. In such cases, the return uplink signals 225 are received by each of a plurality of transponder groups 411 via a respective receive antenna element 406. The output of each receive / transmit signal path 1702 is a return downlink signal 227 corresponding to a respective composite of received return uplink signals. The return downlink signal is created by the receive / transmit signal path 1702. The return downlink signal 227 is transmitted to the array of M ANs 215. In some cases, the ANs 215 are placed at geographically distributed locations (e.g., reception or recovery locations) throughout the end-to-end relay coverage area. In some cases, each transponder group 411 couples a respective one of the receive antenna elements 406 with a respective one of the transmit antenna elements 409. Accordingly, there are L x P different ways for a signal to get from a user terminal 217 located in a user beam coverage area 219 to a particular AN 215. This creates L x P paths between a user terminal 217 and an AN 215. The L x P paths between one user terminal 217 and one AN 215 are referred to collectively as an end-to-end returnmultipath channel 1908 (see FIG. 5). Accordingly, receiving the return uplink signal 225 from a transmission location within a user beam coverage area 219, through the L transponder groups 411, creates L x P return downlink signals 227, each transmitted from one of the transponders 410 (i.e., through L collocated communication paths). Each end-to-end return multipath channel 1908 is associated with a vector in the uplink radiation matrix Ar, the payload matrix E, and a vector in downlink radiation matrix Ct. Note that due to antenna element coverage patterns, in some cases, some of the L paths may have relatively little energy (e.g., 6 dB, 10 dB, 20 dB, 30 dB, or any other suitable power ratio less than other paths). A superposition of return downlink 227 signal is received at each of the ANs 215 (e.g., at M geographically distributed reception or recovery locations). Each return downlink signal 227 comprises a superposition of a plurality of the transmitted return downlink signals 227, resulting in a respective composite return signal. The respective composite return signals are coupled with the return beamformer 231.

[0054] FIG. 5 shows an example of a multipath channel scheme 500 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The multipath channel scheme 500 may illustrate an example model of all the end-to-end return multipath channels from user beam coverage areas 219 to ANs 215. Each polarization type “P” is received by its corresponding matching polarization type (e.g., using Euler angle calibration). There are M x (K x P) such end-to-end return multipath channels in the end-to-end return link (i.e., M from each of the K user beam coverage areas 219 with P polarizations for each K user beam). Channels 1908 connect user terminals in one user beam coverage area 219 to one AN 215 over L x P different receive / transmit signal paths 1702, each path going through a different one of the L x P receive / transmit signal paths (and associated transponders) of the relay. While this effect is referred to as “multipath” herein, this multipath differs from other approaches to multipath communications (e.g., in a mobile radio or multiple-input multiple-output (MIMO) system), as the multiple paths herein are intentionally induced (and, as described herein, affected) by the L x P receive / transmit signal paths. Each of the M x (K x P) end-to-end return multipath channels that originate from a user terminal 217 within a particular user beam coverage area 219 can be modeled by an end-to-end return multipath channel. Each such end-to-end return multipath channel is from a reference (or recovery) location within the user beam coverage area 219 to one of the ANs 215.

[0055] Each of the M x (K x P) end-to-end return multipath channels 1908 may be individually modeled to compute a corresponding element of an M x K x P return channel matrix Hret. The return channel matrix Hret has K x P vectors, each having dimensionality equal to M, such that each vector models the end-to-end return channel gains for multipath communications between a reference location in one of a combination of a respective K user beam coverage area (using a polarization P) and the M ANs 215. Each end-to-end return multipath channel couples one of the M ANs 215 with a reference location within one of K return user beams via L transponder groups 411 (see FTG. 4). In some cases, only a subset of the L transponder groups 411 on the end-to-end relay 203 is used to create the end-to-end return multipath channel (e.g., only a subset is considered to be in the signal path by contributing significant energy to the end-to-end return multipath channel). In some cases, the number of user beams K is greater than the number of transponder groups L that is in the signal path of the end-to-end return multipath channel. Furthermore, in some cases, the number of ANs M is greater than the number of transponder groups L that is in the signal path of the end-to-end return multipath channel 1908. In an example, the element Hret 1,1,1 of the return channel matrix Hret is associated with the channel from a reference location in the first user beam coverage area to the first AN, with a first polarization at the first user terminal 217 and the AN 215. The matrix Hret models the end-to-end channel as the product of the matrices Ct x E x Ar (see FIG. 4). Each element in Hretmodels the end-to-end gain of one end-to-end return multipath channel 1908.

[0056] Due to the multipath nature of the channel, the channel can be subject to a deep fade. Return user beams may be formed by the CPS 205. The CPS 205 computes return beam weights based on the model of these M x (K x P) signal paths and forms the return user beams by applying the return beam weights to the plurality of composite return signals, each weight being computed for each end-to-end return multipath channel that couples the user terminals 217 in one user beam coverage area with one of the plurality of ANs 215. In some cases, the return beam weights are computed before receiving the composite return signal. There is one end-to-end return link from each of the polarizations P of each K user beam coverage areas 219 to the M ANs 215. The weighting (i.e., the complex relative phase / amplitude) of each of the signals received by the M ANs 215 allows those signals to be combined to form a return user beam using the beamforming capability of the CPS 205 within the ground segment 202. The computation of the beam weight matrix is used to determine how to weight each end-to- end return multipath channel 1908, to form the plurality of return user beams, as described inmore detail below. User beams are not formed by directly adjusting the relative phase and amplitude of the signals transmitted by one end-to-end relay antenna element with respect to the phase and amplitude of the signals transmitted by the other end-to-end relay antenna elements. Rather, user beams are formed by applying the weights associated with the M x K x P channel matrix to the M AN signals (each having P components). It is the plurality of ANs 215 and use of multiple polarizations that provide the receive path diversity, single transmitter (user terminal) to multiple receivers (ANs), to enable the use of polarization coding to take advantage of spherical wavefront properties of the multipath channel scheme 500.

[0057] As shown in FIG. 5, the user terminals 217 transmit signals that are of a given polarization using an antenna element corresponding to the given polarization. These signals are received by the ANs 215 using antenna elements that correspond to the given polarization with which the signals were transmitted. However, given the relative motion that may occur between the ANs 215 and the user terminals 217 (e.g., including motion of the ANs 215, the relay, the user terminals 217, or any combination thereof), relative Euler angles may be present between the ANs 215 and the user terminals 217. As such, each tripole receiver (e.g., in this case, the ANs 215) may calculate one or more effective Euler angles (e.g., subweights) to recover the various polarizations that were originally used to transmit the signaling, after which the ANs 215 may combine the signals based on the beam weights and proceed to decode the transmissions (e.g., in accordance with a space time block code or multiple turbo codes used in connection with transmitting the signaling).

[0058] FIG. 6 shows an example of a signal path model 600 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The signal path model 600 may be an example model of signal paths for signals carrying forward data on the end-to-end forward link 201, where a quantity of polarizations supported may be up to P. Forward data is the data that flows from ANs 215 to user terminals 217. Signals in this figure flow from right to left. The signals originate with M ANs 215, which are located in the footprint of the end-to-end relay 203, where each forward uplink signal includes P polarization component. There are K user beam coverage areas 219. Signals from each AN 215 are relayed by L x P receive / transmit signal paths 2001.

[0059] The receive / transmit signal paths 2001 transmit a relayed signal to user terminals 217 in user beam coverage areas 219. Accordingly, there may be L x P different ways for a signal to get from a particular AN 215 to a user terminal 217 located in a user beam coverage area 219. This creates L x P paths between each AN 215 and each user terminal 217. Notethat due to antenna element coverage patterns, some of the L x P paths may have less energy than other paths.

[0060] FIG. 7 shows an example of a multipath channel scheme 700 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The multipath channel scheme 700 may include a model of all the end-to-end forward multipath channels 2208 from the M ANs 215 to the K user beam coverage areas 219 over the P polarizations. As shown in FIG. 7, there is an end-to-end forward multipath channel 2208 that couples each AN 215 to each user beam coverage area 219 over the P polarizations. Each channel 2208 from one AN 215 to one user beam coverage area 219 has multipath induced as a result of L unique paths from an antenna element of the AN 215 through the plurality of transponder groups to the user beam coverage area 219. As such, the (K x P) x M multipath channels 2208 may be individually modeled and the model of each serves as an element of a K x P x M forward channel matrix Hfwd. The forward channel matrix Hfwd has M vectors, each having dimensionality equal to K x P, such that each vector models the end-to-end forward gains for multipath communications between a respective one of the M ANs 215 and reference (or recovery) locations over P polarizations in K forward user beam coverage areas. Each end-to-end forward multipath channel couples one of the M ANs 215 with user terminals 217 serviced by one of K forward user beams via L transponder groups 411. In some cases, only a subset of the L transponder groups 411 on the end-to-end relay 203 are used to create the end-to-end forward multipath channel (i.e., are in the signal path of the end-to-end forward multipath channel). In some cases, the number of user beams K is greater than the number of transponder groups L that are in the signal path of the end-to- end forward multipath channel. Furthermore, in some cases, the number of ANs M is greater than the number of transponder groups L that are in the signal path of the end-to-end forward multipath channel.

[0061] Hfwd may represent the end-to-end forward link as the product of matrices At x E x Cr. Each element in Hfwd is the end-to-end forward gain due to the multipath nature of the path and can be subject to a deep fade. An appropriate beam weight may be computed for each of the plurality of end-to-end forward multipath channels 2208 by the CPS 205 within the ground segment 202 to form forward user beams from the set of M ANs 215 to each user beam coverage area 219 using P polarizations. The plurality of ANs 215 provide transmit path diversity, by using multiple transmitters (ANs) to a single receiver (user terminal), toenable the successful transmission of information to any user terminal 217 in the presence of the intentionally induced multipath channel.

[0062] As shown in FIG. 7, the ANs 215 transmit signals that are of a given polarization using an antenna element corresponding to the given polarization. These signals are received by the user terminals 217 using one or more antenna elements that correspond to the given polarization with which the signals were transmitted. However, given the relative motion that may occur between the ANs 215 and the user terminals 217 (e.g., including motion of the ANs 215, the relay, the user terminals 217, or any combination thereof), relative Euler angles may be present between the ANs 215 and the user terminals 217. As such, each tripole receiver (e.g., in this case, the user terminals 217) may calculate one or more effective Euler angles (e.g., sub-weights) to recover the various polarizations that were originally used to transmit the signaling, after which the user terminals 217 may combine the signals based on the beam weights and proceed to decode the transmissions (e.g., in accordance with a space time block code or multiple turbo codes used in connection with transmitting the signaling).

[0063] FIG. 8 shows an example of a satellite scheme 800 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The satellite scheme may include an example satellite 802 that can be used as an end-to-end relay 203. The satellite 802 has transmit antenna 401 and a receive antenna 402. The receive antenna 402 includes an array of receive antenna elements 406, and may include a receive reflector (not shown) that illuminates the receive antenna elements 406. The transmit antenna 401 includes an array of transmit antenna elements 409 and may include a transmit reflector (not shown) that is illuminated by the transmit antenna elements 409. In some cases, the same reflector is used for both receive and transmit. In some cases, one port of the antenna element is used for receiving and another port for transmission. Each antenna element may support multiple polarizations (e.g., a tripole antenna).

[0064] The example satellite 802 also includes multiple transponders 410. A transponder 410 connects the output from one port of a receive antenna element 406 to the input of one port of a transmit antenna element 409. In some cases, the transponder 410 amplifies the received signal. Each receive antenna element outputs a unique received signal for each of multiple polarizations. For example, to support communication in accordance with up to three orthogonal polarizations, the receive antenna elements 406 may be coupled with three transponders 410, one each for each of the orthogonal polarizations. Similarly, the three transponders 410 may be coupled to a transmit antenna element 409 as part of the relay signalchain. The transponders 410 may be arranged in transponder groups 411 including one transponder 410 for each of the multiple polarizations. In some cases, a subset of receive antenna elements 406 receive a signal from an Earth transmitter, such as either a user terminal 217 in the case of a return link signal or an AN 215 in the case of a forward link signal. In some of these cases, the gain of each receive antenna element in the subset for the received signal is within a relatively small range. In some cases, the range is 3 dB. In other cases, the range is 6 dB. In yet other cases, the range is 10 dB. Accordingly, the satellite will receive a signal at each of a plurality of receive antenna elements 406 of the satellite, the communication signal originating from an Earth transmitter, such that a subset of the receive antenna elements 406 receives the communication signal at a signal level that is not substantially less than a signal level corresponding to a peak gain of the receive antenna element 406.

[0065] In some cases, at least 10 transponder groups 41 1 are provided within the satellite 802. In another case, at least 100 transponder groups 411 are provided in the satellite 802. In yet another case, the number of transponders per polarity may be in the range of 2, 4, 8, 16, 32, 64, 128, 256, 212, 1024 or numbers in-between or greater. In some cases, the transponder 410 includes a low noise amplifier (LNA) 412, a frequency converter 414 and associated filters and a power amplifier (PA) 420. In some cases in which the uplink frequency and downlink frequency are the same, the transponder does not include a frequency converter. In other cases, the plurality of receive antenna elements operate at a first frequency and the plurality of transmit antenna elements operate at a second frequency. The receive antenna element 406 is coupled with the input of the LNA 412. Accordingly, the LNA independently amplifies the unique received signal provided by the receive antenna element associated with the transponder 410. In some cases, the output of the LNA 412 is coupled with the frequency converter 414. The frequency converter 414 may convert the amplified signal between the first frequency and the second frequency.

[0066] In some examples, the calibration support module 424 and the satellite beacon generator 426 may support closed loop calibration or correction operations. For example, the calibration support module 424 may include the satellite beacon generator 426, which may transmit a beacon signal for another device to receive and, based on the beacon signal, determine one or more closed loop parameters and make one or more closed loop adjustments to one or more communication parameters.

[0067] FIG. 9 shows an example of a ground segment scheme 900 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The ground segment scheme 900 may include an example ground segment 202 for an end-to-end beamforming system. FIG. 11 may illustrate, for example, ground segment 202 of FIG. 2. The ground segment 202 comprises CPS 205, distribution network 218, and ANs 215. CPS 205 comprises beam signal interface 224, forward / return beamformer 213, distribution interface 236, and beam weight generator 910.

[0068] For the forward link, beam signal interface 224 obtains forward beam signals (FBS) 211 associated with each of the forward user beams. Beam signal interface 224 may include forward beam data multiplexer 226 and forward beam data stream modulator 228. Forward beam data multiplexer 226 may receive forward user data streams 209 comprising forward data for transmission to user terminals 217. Forward user data streams 209 may comprise, for example, data packets (e.g., TCP packets, UDP packets, etc.) for transmission to the user terminals 217 via the end-to-end beamforming system 200 of FIG. 2. Forward beam data multiplexer 226 groups (e.g., multiplexes) the forward user data streams 209 according to their respective forward user beam coverage areas to obtain forward beam data streams 232. Forward beam data multiplexer 226 may use, for example, time-domain multiplexing, frequency-domain multiplexing, or a combination of multiplexing techniques to generate forward beam data streams 232. Forward beam data stream modulator 228 may modulate the forward beam data streams 232 according to one or more modulation schemes (e.g., mapping data bits to modulation symbols) to create the forward beam signals 211, which are passed to the forward / return beamformer 213. In some cases, the forward beam data stream modulator 228 may frequency multiplex multiple modulated signals to create a multi-carrier beam signal 211. Beam signal interface 224 may, for example, implement the functionality of feeder link modems 207 discussed with reference to FIG. 2.

[0069] Forward / return beamformer 213 may include forward beamformer 229 and return beamformer 231 . Beam weight generator 910 generates an M x K x P forward beam weight matrix 918. Techniques for generating the M x K x P forward beam weight matrix 918 are discussed in more detail below. Forward beamformer 229 may include a matrix multiplier that calculates M access-node specific forward signals 216. For example, this calculation can be based on a matrix product of the M x K x P forward beam weight matrix 918 and a vector of the K forward beam signals 211 (where each forward beam signal includes P polarization coded components). In some examples, each of the K forward beam signals 211 may beassociated with one of F forward frequency sub-bands. In this case, the forward beamformer 229 may generate samples for the M access-node specific forward signals 216 for each of the F forward frequency sub-bands (e.g., effectively implementing the matrix product operation for each of the F sub-bands for respective subsets of the K forward beam signals 211. Distribution interface 236 distributes (e.g., via distribution network 218) the M access nodespecific forward signals 216 to the respective ANs 215.

[0070] In some examples, the forward / return beamformer 213 (or other element of the CPS 205) may include a forward encoder 956 and a return decoder 954. For example, the forward encoder may encode the forward beam signals 211 (e.g., using polarization coding such as using a space time block code or multiple turbo codes) to generate multiple polarizations (e.g., three polarizations) for each forward beam signal 211. Each of these signals (e.g., that are of the polarizations generated by the forward encoder 956) may be processed by a beamforming element 952 of the forward beamformer 229 (e.g., as described in relation to the forward beamformer 229 or elsewhere herein). In some examples, each beamforming element 952 may process the signaling independently of other beamforming elements 952 that may be processing signaling of a different polarization generated by the forward encoder 956 (e.g., even if they are associated with a same forward beam signal 211).

[0071] For the return link, the distribution interface 236 obtains composite return signals 208 from ANs 215 (e.g., via distribution network 218). Each return data signal from user terminals 217 may be included in multiple (e.g., up to and including all) of the composite return signals 208. Beam weight generator 910 generates a K x M return beam weight matrix 937. Techniques for generating the K x M return beam weight matrix 937 are discussed in more detail below. Return beamformer 231 calculates K return beam signals 915 for the K return user beam coverage areas. For example, this calculation can be based on a matrix product of the return beam weight matrix 937 and a vector of the respective composite return signals 208. Beam signal interface 224 may include return beam signal demodulator 252 and return beam data de-multiplexer 254. Return beam signal demodulator 252 may demodulate each of the return beam signals to obtain K return beam data streams 234 associated with the K return user beam coverage areas. Return beam data de-multiplexer 254 may de-multiplex each of the K return beam data streams 234 into respective return user data streams 235 associated with the return data signals transmitted from user terminals 217. In some examples, each of the return user beams may be associated with one of R return frequency sub-bands. In this case, the return beamformer 231 may generate respective subsets of thereturn beam signals 915 associated with each of the R return frequency sub-bands (e.g., effectively implementing the matrix product operation for each of the R return frequency subbands to generate respective subsets of the return beam signals 915).

[0072] Similarly, for the return link, the forward / retum beamformer 213 (or other element of the CPS 205) may include the return decoder 954. For example, the return beamformer 231 may include multiple beamforming elements 950 that may process the composite return signals 208 received from the ANs 215. The beamforming elements 950 may process signaling (e.g., as described with reference to the return beamformer 231 or elsewhere herein) of multiple polarizations received at the ANs 215 and may pass the resulting signaling to the return decoder 954. The return decoder 954 may decode these signals that correspond to the multiple polarizations according to the polarization coding to generate the return beam signals 915, which may be further processed as described herein.

[0073] FIG. 10 shows an example of a beamforming scheme 1000 that supports beamforming and block coding with three orthogonal axis element antenna in accordance with examples as disclosed herein. The beamforming scheme 1000 may include an example forward / return beamformer 213. The forward / return beamformer 213 comprises a forward beamformer 229, a forward timing module 945, a return beamformer 231, and a timing module 947. The forward timing module 945 associates each of the M access node-specific forward signals 216 with a time stamp (e.g., multiplexes the time stamp with the access nodespecific forward signal in a multiplexed access node-specific forward signal) that indicates when the signal is desired to arrive at the end-to-end relay. In this way, the data of the K forward beam signals 21 1 that is split in a splitting module 904 within the forward beamformer 229 may be transmitted at the appropriate time by each of the ANs 215. The timing module 947 aligns the receive signals based on time stamps. Samples of the M AN composite return signals (CRS) 208 are associated with time stamps indicating when the particular samples were transmitted from the end-to-end relay. Timing considerations and generation of the time stamps are discussed in greater detail below.

[0074] The forward beamformer 229 has a data input 925, a beam weights input 920 and an access node output 923. The forward beamformer 229 applies the values of an M x K x P beam weight matrix to each of the K forward data signals 211 (where each forward data signal includes P polarization coded components) to generate M access node specific forward signals 221 , each having components of K weighted forward beam signals. The forward beamformer 229 may include a splitting module 904 and M forward weighting and summingmodules 233. The splitting module 904 splits (e.g., duplicates) each of the K forward beam signals 211 into M groups 906 of K forward beam signals, one group 906 for each of the M forward weighting and summing modules 233. Accordingly, each forward weighting and summing module 233 receives all K forward data signals 211.

[0075] A forward beam weight generator 917 generates an M x K forward beam weight matrix 918, where each matrix element is a vector of P beam weights. In some cases, the forward beam weight matrix 918 is generated based on a channel matrix in which the elements are estimates of end-to-end forward gains for each of the K x M x P end-to-end forward multipath channels to form a forward channel matrix, as discussed further below. Estimates of the end-to-end forward gain are made in a channel estimator 919. In some cases, the channel estimator has a channel data store 921 that stores data related to various parameters of the end-to-end multipath channels, as is discussed in further detail below. The channel estimator 919 outputs an estimated end-to-end gain signal to allow the forward beam weight generator 917 to generate the forward beam weight matrix 918. Each of the weighting and summing modules 233 are coupled with receive respective vectors of beamforming weights of the forward beam weight matrix 918 (only one such connection is show in FIG. 10 for simplicity). The first weighting and summing module 233 applies a weight equal to the value of the 1,1 element of the M x K forward beam weight matrix 918 to the first of the K forward beam signals 211 (discussed in more detail below). A weight equal to the value of the 1,2 element of the M x K forward beam weight matrix 918 is applied to the second of the K forward beam signals 211. The other weights of the matrix are applied in like fashion, on through the Kth forward beam signal 211, which is weighted with the value equal to the 1,K element of the M x K forward beam weight matrix 918. Each of the K weighted forward beam signals 903 are then summed and output from the first weighting and summing module 233 as an access node-specific forward signal 216 (e.g., which has P polarization components). The access node-specific forward signal 216 output by the first weighting and summing module 233 is then coupled with the timing module 945. The timing module 945 outputs the access node-specific forward signal 216 to the first AN 215 through a distribution network 218 (see FIG. 2). Similarly, each of the other weighting and summing modules 233 receive the K forward beam signals 211, and weight and sum the K forward beam signals 211. The outputs from each of the M weighting and summing modules 233 are coupled through the distribution network 218 to the associated M ANs 215 so that the output from the mth weighting and summing module is coupled with the mth AN 215. In some cases, jitterand uneven delay through the distribution network, as well as some other timing considerations, are handled by the timing module 945 by associating a time stamp with the data. Details of an example timing technique are provided below with regard to FIGs. 36 and 37.

[0076] As a consequence of the beam weights applied by the forward beamformers 229 at the ground segment 202, the signals that are transmitted from the ANs 215 through the end- to-end relay 203 form user beams. The size and location of the beams that are able to be formed may be a function of the number of ANs 215 that are deployed, the number and antenna patterns of relay antenna elements that the signal passes through, the location of the end-to-end relay 203, and / or the geographic spacing of the ANs 215.

[0077] Referring now to the end-to-end return link 223 shown in FIG. 2, a user terminal 217 within one of the user beam coverage areas 219 transmits signals up to the end-to-end relay 203. The signals are then relayed down to the ground segment 202. The signals are received by ANs 215.

[0078] Referring once again to FIG. 10, M return downlink signals 227 are received by the M ANs 215 and are coupled, as composite return signals 208, from the M ANs 215 through the distribution network 218 and received in an access node input 931 of the return beamformer 231. Timing module 947 aligns the composite return signals from the M ANs 215 to each other and outputs the time-aligned signals to the return beamformer 231. A return beam weight generator 935 generates the return beam weights as a K x M return beam weight matrix 937, where each matrix element is a vector of P beam weights, based on information stored in a channel data store 941 within a channel estimator 943. The return beamformer 231 has a beam weights input 939 through which the return beamformer 231 receives the return beam weight matrix 937. Each of the M AN composite return signals 208 is coupled with an associated one of M splitter and weighting modules 239 within the return beamformer 231. Each splitter and weighting module 239 splits the time-aligned signal into K copies 909. The splitter and weighting modules 239 weight each of the K copies 909 using the k, m element of the K x M return beam weight matrix 937. Each set of K weighted composite return signals 911 is then coupled with a combining module 913. In some cases, the combining module 913 combines the kth weighted composite return signal 911 output from each splitter and weighting module 239. The return beamformer 231 has a return data signal output 933 that outputs K return beam signals 915, each having the samples associated with one of the K return user beams (e.g., the samples received through each of the M ANs). Each of the Kreturn beam signals 915 includes P polarization components and may have samples from one or more user terminals 217. The polarization module 1020 applies polarization coding to obtain beamformed return beam signals 915. The K combined and aligned, beamformed return beam signals 915 are coupled with the feeder link modems 207 (see FIG. 2). Note that the return timing adjustment may be performed after the splitting and weighting. Similarly, for the forward link, the forward timing adjustment may be performed before the beamforming.

[0079] As discussed above, forward beamformer 229 may perform matrix product operations on input samples of K forward beam signals 211 to calculate M access nodespecific forward signals 216 (e.g., where each access node-specific forward signal 216 includes P polarization components) in real-time. As the beam bandwidth increases (e.g., to support shorter symbol duration) and / or K and M become large, the matrix product operation becomes computationally intensive and may exceed the capabilities of a single computing node (e.g., a single computing server, etc.). The operations of return beamformer 231 are similarly computationally intensive. Various approaches may be used to partition computing resources of multiple computing nodes in the forward / return beamformer 213. In one example, the forward beamformer 229 of FIG. 10 may be partitioned into separate weighting and summing modules 233 for each of the M ANs 215, which may be distributed into different computing nodes. Generally, the considerations for implementations include cost, power consumption, scalability relative to K, M, and bandwidth, system availability (e.g., due to node failure, etc.), upgradeability, and system latency. The example above is per row (or column). Vice versa is possible. Other manners of grouping the matrix operations may be considered (e.g., split into four with [1,1 to K / 2,M / 2], [ . . . ], computed individually and summed up).

[0080] In some examples, the forward beamformer may include the polarization module 1022. The polarization module 1022 may operate in concert with the splitting module 904 (and other elements of the forward beamformer) to process the incoming forward beam signals 211 on a per-polarization basis. For example, the incoming forward beam signals 211 may be of various polarizations (e.g., as a result of applying the space time block code or multiple turbo codes) and the polarization module 1022 may determine or obtain the polarization of each of these signals and provide the signals to the other elements of the forward beamformer so that each of these component signals (e.g., that individually correspond to respective polarizations) are assigned weights for beamforming.

[0081] Similarly, in some examples, the return beamformer may include the polarization module 1020. The polarization module 1020 may operate in concert with the combining module 913 (and other elements of the return beamformer) to process the incoming forward beam signals 211 on a per-polarization basis. For example, the composite return signals 208 may be of various polarizations and the polarization module 1020 may apply polarization coding to obtain K return beam signals 915.

[0082] It should be noted that these methods describe examples of implementations, and that the operations and the steps may be rearranged or otherwise modified such that other implementations are possible. In some examples, aspects from two or more of the methods may be combined. For example, aspects of each of the methods may include steps or aspects of the other methods, or other steps or techniques described herein.

[0083] Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, 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.

[0084] The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with 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 thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, 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).

[0085] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Featuresimplementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

[0086] Computer readable media includes both non transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer readable media may include RAM, ROM, electrically erasable programmable read-only memory (EEPROM), flash memory, compact disk read-only memory (CDROM) or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer, or a genera] purpose or special purpose processor. Also, any connection is properly termed a computer readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer readable media.

[0087] As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of’ or “one or more of’) indicates an inclusive list such that, for example, a list of 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” shall not be construed as a reference to a closed set of conditions. For example, an exemplary step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on.”

[0088] In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished byfollowing the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label, or other subsequent reference label.

[0089] The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “exemplary” used herein means “serving as an example, instance, or illustration,” and not “preferred” or “advantageous over other examples.” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, well known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

[0090] The description herein is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the 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 disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

CLAIMSWhat is claimed is:

1. A system for providing a communication service to user terminals (217) distributed over a service area via a wireless relay (203) comprising multiple return receive / transmit signal paths (1908), comprising: a plurality of access nodes (215) at distributed locations, wherein communications between the user terminals (217) and the distributed locations via the wireless relay (203) are subject to near-field communication effects at a carrier frequency of the communications, and wherein the plurality of access nodes (215) receive respective composite return signals (208), each of the respective composite return signals (208) comprising up to three respective orthogonal component fields (320) and a composite of return data signals (225) transmitted from a plurality of the user terminals (217) and relayed by the wireless relay (203), each of the plurality of access nodes (215) comprising: an antenna (310) with at least three elements (315) oriented to capture the respective orthogonal component fields (320) of the respective composite return signals (208), and a receiver that receives the respective composite return signal (208) from the wireless relay (203) via the antenna (310), the respective composite return signal (208) comprising respective component signals associated with the respective orthogonal component fields (320); a distribution network (218) that obtains the respective composite return signals (208) from the plurality of access nodes (215), wherein the distribution network (218) corrects the respective composite return signals (208) for the near-field communication effects, timing and phase for respective path delays and phase shifts between the wireless relay (203) and the plurality of access nodes (215); a return beamformer (231) coupled with the distribution network (218), the return beamformer (231) comprising a matrix multiplier that obtains respective return component beam field signals associated with each of the respective orthogonal component fields (320) for a return user beam coverage area based on a matrix product of a return beam weight matrix and a vector of the respective composite return signals; anda return decoder (954) that performs decoding of information of the return data signals (225) across the respective return component beam field signals.

2. The system of claim 1, wherein each of the plurality of access nodes (215) comprises a closed loop controller that measures a drift rate of one or more phase shifts associated with the respective composite return signal (208) and corrects the respective composite return signal (208) based at least in part on the drift rate of the one or more phase shifts.

3. The system of any one of claims 1 and 2, wherein: the closed loop controller determines a net Euler angle between individual user terminals (217) of the user terminals (217) and the access node (215) that comprises the closed loop controller; and the closed loop controller corrects the respective composite return signal based at least in part on the determined net Euler angle.

4. The system of any one of claims 1 through 3, wherein the return decoder (954) performs the decoding according to a space-time block code across multiple respective orthogonal component fields (320) of the composite return signal (208) or a set of individual turbo block codes corresponding to the respective orthogonal component fields (320) in the composite return signal (208).

5. The system of any one of claims 1 through 4, wherein: the antenna (310) is a tripole antenna and the at least three elements (315) are orthogonal dipole elements positioned with a common origin; or the at least three elements (315) are orthogonal loop elements positioned with a common origin.

6. A system for providing a communication service to user terminals (217) distributed over a service area via a wireless relay (203) comprising multiple forward receive / transmit signal paths (2208), comprising: a plurality of access nodes (215) at distributed locations, wherein communications between the user terminals (217) and the distributed locations via the wireless relay (203) are subject to near-field communication effects at a carrier frequency of the communications, and wherein the plurality of access nodes (215) obtain respective composite forward signals, each of the respective composite forwardsignals comprising up to three respective orthogonal component fields (320) and a composite of forward data signals (221) transmitted to a plurality of the user terminals (217) and relayed by the wireless relay (203), each of the plurality of access nodes (215) comprising: an antenna (310) with at least three elements (315) oriented to transmit the respective orthogonal component fields (320) of the respective composite forward signal, and a transmitter that transmits the respective composite forward signal to the wireless relay (203) via the antenna (310), the respective composite forward signal comprising respective component signals associated with the respective orthogonal component fields (320); a forward encoder (956) that performs encoding of information of the forward data signals across respective forward component beam field signals associated with each of the respective orthogonal component fields (320) for a forward user beam coverage area; a forward beamformer (229) comprising a matrix multiplier that obtains a vector of the respective composite forward signals based on a matrix operation applied to a forward beam weight matrix and the respective forward component beam field signals; and a distribution network (218) coupled with the forward beamformer (229) that provides the respective forward component beam field signals to the plurality of access nodes (215), wherein the distribution network (218) corrects the respective forward component beam field signals for the near-field communication effects, timing and phase for respective path delays and phase shifts between the wireless relay (203) and the plurality of access nodes (215).

7. The system of claim 6, wherein each of the plurality of access nodes (215) comprises a closed loop controller that measures a drift rate of one or more phase shifts associated with the respective composite forward signal and corrects the respective composite forward signal based at least in part on the drift rate of the one or more phase shifts.

8. The system of any one of claims 6 and 7, wherein: the closed loop controller determines a net Euler angle between individual user terminals (217) of the user terminals (217) and the access node (215) that comprises the closed loop controller; and the closed loop controller corrects the respective composite forward signal based at least in part on the determined net Euler angle.

9. The system of any one of claims 6 through 8, wherein the forward encoder performs the encoding according to a space-time block code across multiple respective orthogonal component fields (320) of the composite forward signal or a set of individual turbo block codes corresponding to the respective orthogonal component fields (320) in the composite forward signal.

10. The system of any one of claims 6 through 9, wherein: the antenna (310) is a tripole antenna and the at least three elements (315) are orthogonal dipole elements positioned with a common origin; or the at least three elements (315) are orthogonal loop elements positioned with a common origin.

11. A method for providing a communication service to user terminals (217) distributed over a service area via a wireless relay (203) comprising multiple return receive / transmit signal paths (1908), comprising: receiving, at a plurality of access nodes (215) at distributed locations, respective composite return signals (208), each of the respective composite return signals (208) comprising up to three respective orthogonal component fields (320) and a composite of return data signals (225) transmitted from a plurality of the user terminals (217) and relayed by the wireless relay (203), wherein communications between the user terminals (217) and the distributed locations via the wireless relay (203) are subject to near-field communication effects at a carrier frequency of the communications, and wherein each of the plurality of access nodes (215) comprises: an antenna (310) with at least three elements (315) oriented to capture the respective orthogonal component fields (320) of the respective composite return signals (208), and a receiver that receives the respective composite return signal (208) from the wireless relay (203) via the antenna (310), the respectivecomposite return signal (208) comprising respective component signals associated with the respective orthogonal component fields (320); obtaining, at a distribution network (218), the respective composite return signals (208) from the plurality of access nodes (215), wherein the distribution network (218) corrects the respective composite return signals (208) for the near- field communication effects, timing and phase for respective path delays and phase shifts between the wireless relay (203) and the plurality of access nodes (215); obtaining, with a matrix multiplier of a return beamformer (231) that is coupled with the distribution network (218), respective return component beam field signals associated with each of the respective orthogonal component fields (320) for a return user beam coverage area based on a matrix product of a return beam weight matrix and a vector of the respective composite return signals; and decoding, with a return decoder (954), information of the return data signals (225) across the respective return component beam field signals.

12. The method of claim 11, wherein each of the plurality of access nodes (215) comprises a closed loop controller that measures a drift rate of one or more phase shifts associated with the respective composite return signal (208) and corrects the respective composite return signal (208) based at least in part on the drift rate of the one or more phase shifts.

13. The method of any one of claims 11 and 12, wherein: the closed loop controller determines a net Euler angle between individual user terminals (217) of the user terminals (217) and the access node (215) that comprises the closed loop controller; and the closed loop controller corrects the respective composite return signal based at least in part on the determined net Euler angle.

14. The method of any one of claims 11 through 13, wherein the return decoder (954) performs the decoding according to a space-time block code across multiple respective orthogonal component fields (320) of the composite return signal (208) or a set of individual turbo block codes corresponding to the respective orthogonal component fields (320) in the composite return signal (208).

15. The method of claim 11, wherein: the antenna (310) is a tripole antenna and the at least three elements(315) are orthogonal dipole elements positioned with a common origin; or the at least three elements (315) are orthogonal loop elements positioned with a common origin.

16. A method for providing a communication service to user terminals (217) distributed over a service area via a wireless relay (203) comprising multiple forward receive / transmit signal paths (2208), comprising: obtaining, at a plurality of access nodes (215) at distributed locations, respective composite forward signals, each of the respective composite forward signals comprising up to three respective orthogonal component fields (320) and a composite of forward data signals (221) transmitted to a plurality of the user terminals (217) and relayed by the wireless relay (203), wherein communications between the user terminals (217) and the distributed locations via the wireless relay (203) are subject to near- field communication effects at a carrier frequency of the communications, and wherein each of the plurality of access nodes (215) comprises: an antenna (310) with at least three elements oriented to transmit the respective orthogonal component fields (320) of the respective composite forward signal, and a transmitter that transmits the respective composite forward signal to the wireless relay (203) via the antenna (310), the respective composite forward signal comprising respective component signals associated with the respective orthogonal component fields (320); encoding, with a forward encoder (956), information of the forward data signals across respective forward component beam field signals associated with each of the respective orthogonal component fields (320) for a forward user beam coverage area; obtaining, with a matrix multiplier of a forward beamformer (229), a vector of the respective composite forward signals based on a matrix operation applied to a forward beam weight matrix and the respective forward component beam field signals; and providing, at a distribution network (218) coupled with the forward beamformer (229), the respective forward component beam field signals to the pluralityof access nodes (215), wherein the distribution network (218) corrects the respective forward component beam field signals for the near-field communication effects, timing and phase for respective path delays and phase shifts between the wireless relay (203) and the plurality of access nodes (215).

17. The method of claim 16, wherein each of the plurality of access nodes (215) comprises a closed loop controller that measures a drift rate of one or more phase shifts associated with the respective composite forward signal and corrects the respective composite forward signal based at least in part on the drift rate of the one or more phase shifts.

18. The method of any one of claims 16 and 17, wherein: the closed loop controller determines a net Euler angle between individual user terminals of the user terminals (217) and the access node (215) that comprises the closed loop controller; and the closed loop controller corrects the respective composite forward signal based at least in part on the determined net Euler angle.

19. The method of any one of claims 16 through 18, wherein the forward encoder performs the encoding according to a space-time block code across multiple respective orthogonal component fields (320) of the composite forward signal or a set of individual turbo block codes corresponding to the respective orthogonal component fields (320) in the composite forward signal.

20. The method of any one of claims 16 through 19, wherein: the antenna (310) is a tripole antenna and the at least three elements (315) are orthogonal dipole elements positioned with a common origin; or the at least three elements (315) are orthogonal loop elements positioned with a common origin.

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