Multi-beam phased array antenna with disjoint sub-array groups

Abstract

The present disclosure provides a multi-beam phased array antenna system, which includes a beamformer that converts between a plurality of subarray signals and a plurality of beam signals in response to a control signal. The system further includes a plurality of subarrays that transmit a plurality of beams corresponding to the plurality of beam signals. Each subarray includes a plurality of radiating elements. Each subarray further includes a subarray beamforming circuit that adjusts an RF signal transmitted by the radiating element in response to a corresponding beam weight and converts between the adjusted RF signal and a corresponding subarray signal. The system further includes a controller that determines two or more beams, where the two or more beams belong to the same communication type. The beamformer assigns non-overlapping subarray subgroups to each of the determined two or more beams. The controller further provides the beam weight to each of the plurality of subarrays and provides the control signal to the beamformer.

Description

[0001] Related Applications

[0002] This application claims the benefit of priority of U.S. Provisional Application No. 62 / 959,146, filed on January 9, 2020, entitled "Reconfigurable Multi-Beam Phased Array Antenna", the entire content of which is incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to antenna systems. More particularly, the present disclosure relates to an antenna system having a phased array antenna with multiple sub-arrays for simultaneously transmitting multiple beams. Background Art

[0004] An antenna array (or array antenna) is a group of multiple radiating elements that work together as a single antenna to transmit or receive radio waves. The individual radiating elements (commonly referred to simply as "elements") can be connected by circuitry to a receiver and / or transmitter that applies the appropriate amplitude and / or phase adjustment of the signals received and / or transmitted by the radiating elements. When used for transmission, the radio waves radiated by each individual radiating element combine and superimpose on each other, thus adding together (constructively interfering) to enhance the power radiated in the desired direction and canceling (destructively interfering) to reduce the power radiated in other directions. Similarly, when used for reception, the individually received signals from the individual radiating elements are combined in the appropriate amplitude and / or phase relationship to enhance the signal received from the desired direction and cancel signals from undesired directions.

[0005] An antenna array can achieve increased gain (directivity) with radio wave beams that are narrower than those achievable by a single antenna. Generally speaking, the use of a larger number of individual radiating elements will increase the gain and narrow the beam. Some antenna arrays (such as phased array radars) can consist of thousands of individual antennas. Arrays can be used to achieve greater gain (which increases communication reliability), cancel interference from specific directions, electronically control the radio beam to point in different directions, and / or for radio direction finding. Summary of the Invention

[0006] One example relates to a multi-beam phased array antenna system. The multi-beam phased array antenna system may include a beamformer that converts between a plurality of sub-array signals and a plurality of beam signals in response to a control signal. The multi-beam phased array antenna system may further include a plurality of sub-arrays that transmit a plurality of beams corresponding to the plurality of beam signals. Each sub-array of the plurality of sub-arrays may include a plurality of radiating elements. Each sub-array may further include sub-array beamforming circuitry that adjusts RF signals transmitted by the plurality of radiating elements in response to corresponding beam weights and converts between the adjusted RF signals and a corresponding sub-array signal of the plurality of sub-array signals, wherein the corresponding sub-array signal corresponds to a particular beam of the plurality of beams. The multi-beam phased array antenna system may further include a controller that determines two or more beams of the plurality of beams, wherein the two or more beams are of the same communication type. The controller may assign a non-overlapping sub-group of sub-arrays of the plurality of sub-arrays to each of the selected two or more beams such that each sub-array of the plurality of sub-arrays is assigned to only one particular beam of the plurality of beams. The controller may further provide corresponding beam weights to each of the plurality of sub-arrays based on the assignment and provide a control signal to the beamformer based on the assignment. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 A block diagram of a multi-beam phased array antenna system is shown.

[0008] Figure 2 A block diagram of a sub-array of a phased array antenna system is shown.

[0009] Figure 3 A block diagram of a multi-beam phased array antenna system having a beamformer including a plurality of beamforming networks (BFNs) is shown.

[0010] Figure 4 A block diagram of a multi-beam phased array antenna system having a beamformer including digital circuitry is shown.

[0011] Figure 5 A block diagram of a multi-beam phased array antenna system having a beamformer including a system located in a beam switching circuit is shown.

[0012] Figure 6 A first example of a phased array antenna communicating simultaneously on two beams is shown.

[0013] Figure 7 A second example of a phased array antenna communicating with two beams simultaneously is shown.

[0014] Figure 8 A third example of a phased array antenna communicating simultaneously on two beams is shown.

[0015] Figure 9 An exemplary graph showing the on-axis gain-noise temperature of different numbers of subarrays allocated to two beams of a phased array antenna.

[0016] Figure 10 A first example of an antenna system having two phased array antennas is shown, where each phased array antenna simultaneously transmits two or more different beams.

[0017] Figure 11 A second example of an antenna system having two phased array antennas is shown, where each phased array antenna simultaneously transmits two or more different beams.

[0018] Figure 12 A first example of an antenna system having two phased array antennas is shown, where each phased array antenna simultaneously communicates on two or more different beams.

[0019] Figure 13 An example of a subarray of a phased array antenna operating in receive mode is shown.

[0020] Figure 14 An example of a subarray of a phased array antenna operating in transmit mode is shown.

[0021] Figure 15 An example of a subarray of a phased array antenna operating in half-duplex mode is shown.

[0022] Figure 16 An example of a subarray of a phased array antenna operating in frequency-division duplex mode is shown.

[0023] Figure 17 An example of a subarray of a phased array antenna operating in polarization duplex mode is shown. Detailed Description

[0024] The present disclosure describes a multi-beam phased array antenna system that can simultaneously transmit multiple beams. The multi-beam phased array antenna system can be mounted on an entity (e.g., an aircraft or a ground vehicle) and used to communicate with an external entity or multiple external entities (e.g., one or more satellites). Each of the multiple beams can represent multiple radio frequency (RF) signals that interfere constructively and / or destructively to provide desired characteristics. The multi-beam phased array antenna system includes a phased array antenna that can be formed by multiple subarrays. In some examples, the subarrays are arranged in a tile form. Each of the multiple subarrays includes multiple radiating elements for transmitting multiple beams to another entity through free space.

[0025] A multi-beam phased array antenna system may include a beamformer that converts between a plurality of sub-array signals and a plurality of beam signals, where each of the beam signals corresponds to one of the plurality of beams. In addition, each of the plurality of sub-array signals is provided to one and only one of the sub-arrays of the phased array antenna. The beamformer may be composed of digital logic components, analog circuits, or a combination thereof.

[0026] Each of the plurality of sub-arrays may include a sub-array beamforming circuit that adjusts RF signals transmitted by a plurality of corresponding radiating elements based on beam weights. In addition, the sub-array beamforming circuit may be configured to convert between the adjusted RF signals and a corresponding sub-array signal of the plurality of sub-array signals. In some examples, the beamforming circuit may include a sub-array beamforming network (BFN) coupled to the beamformer and a plurality of radio frequency integrated circuit (RFIC) chips coupled to the corresponding radiating elements.

[0027] The multi-beam phased array antenna system may include a controller that dynamically controls the operation of each of the plurality of sub-arrays and the beamformer. More particularly, the controller may be configured / programmed to determine two or more beams from the plurality of beams. The two or more determined beams include two beams of the same communication type. As used herein, "communication type" refers to the direction of communication (such as transmission or reception) such that the two or more determined beams include at least two receive beams or at least two transmit beams. If at least one of the frequency, polarization, and pointing direction of two beams of the same communication type is different, then the two beams are different. In response to determining two or more beams, the controller assigns a disjoint sub-group of sub-arrays from the plurality of sub-arrays to each of the two or more determined beams. In this way, each of the plurality of sub-arrays is assigned to one and only one specific beam of the plurality of beams. The controller may provide corresponding beam weights to each of the plurality of sub-arrays based on the assignment and provide a control signal to the beamformer.

[0028] The controller can be configured to change the determination of two or more beams over time. For example, as the entity to which the multi-beam phased array antenna system is mounted moves and / or the entity (or entities) with which the multi-beam phased array antenna system communicates moves, the controller can dynamically determine the beams for transmitting data and / or receiving data from different satellites (or other entities), and reallocate non-overlapping sub-arrays of the phased array antenna. In this way, a multi-beam phased array antenna system can be employed to achieve make-before-break communication with two satellites simultaneously. For example, consider the case where a multi-beam phased array antenna system is mounted on an entity, and the multi-beam phased array antenna system can be used to provide two-way communication with a first satellite using the phased array antenna. As the communication with the first satellite begins to degrade (e.g., due to a change in the position of the entity), the multi-beam phased array antenna system can use the same phased array antenna to establish two-way communication with a second satellite before losing communication with the first satellite.

[0029] Figure 1 An example of a multi-beam phased array antenna system 100 is shown. The multi-beam phased array antenna system 100 transmits multiple beams simultaneously. As used herein, the term "communicate" (and its derivatives) with reference to a signal refers to the transmission and / or reception of the signal, which neither requires both transmission and reception simultaneously nor precludes transmission or reception. The multi-beam phased array antenna system 100 includes a phased array antenna 104 formed using J sub-arrays 108, where J is an integer greater than one. In some examples, the phased array antenna 104 can represent multiple antennas (e.g., transmit antennas and receive antennas). In other examples, the phased array antenna 104 represents a single antenna.

[0030] In this example, there are 14 sub-arrays 108, labeled SA-1, …, SA-14. In other examples, there may be more or fewer sub-arrays 108. Each sub-array 108 includes a plurality of radiating elements that transmit radio frequency (RF) signals into free space. Each of the J sub-arrays 108 includes a sub-array beamforming circuit that converts between an RF signal and a sub-array signal. More particularly, the sub-array beamforming circuit can include signal paths for combining and / or dividing the RF signals for conversion. Additionally, the sub-array beamforming circuit of each of the J sub-arrays 108 can include circuit components, such as radio frequency integrated circuit (RFIC) chips that can amplify and / or phase-shift the RF signal based on beam weights.

[0031] In some examples, each of the J sub-arrays 108 can have the same shape (e.g., having the same-shaped top surface). Examples of shape a can include a hexagon (as Figure 1as shown), squares, rhombuses, triangles, etc. In other examples, the phased array antenna 104 can include subgroups of different subarrays 108 having different shapes, such as a first group of one or more subarrays 108 having a first shape, a second group of one or more subarrays 108 having a second shape, etc. In other examples, each of the J subarrays 108 can have a different shape. In some examples, the subarrays 108 can be arranged in a regular (e.g., triangular, square, etc.) grid. The subarrays 108 of the grid in such an arrangement can be arranged, for example, edge-to-edge (e.g., forming a continuous aperture). In other examples, the subarrays 108 can be arranged in an irregular pattern.

[0032] The phased array antenna 104 is configured such that non-overlapping subgroups of subarrays 108 are assigned to transmit specific beams of a plurality of beams and can transmit each beam of the plurality of beams with another entity (such as a satellite or a ground station). As used herein, "non-overlapping subgroup" refers to a subgroup within a group (e.g., a group of 14 subarrays) where each individual non-overlapping subgroup does not have a member in common with another non-overlapping subgroup. For example, if the first through seventh subarrays 108 (SA-1,..., SA-7) are assigned to a first beam and the eighth through fourteenth subarrays 108 (SA-8,..., SA-14) are assigned to a second beam, then the first through seventh subarrays 108 (SA-1,..., SA-7) are a first non-overlapping subgroup of subarrays 108 and the eighth through fourteenth subarrays 108 (SA-8,..., SA-14) are a second non-overlapping subgroup of subarrays. In this case, the first beam and the second beam can be in the same or different directions and can be transmitted simultaneously. Thus, the phased array antenna 104 can be employed to transmit and receive different beams transmitted to and from the same entity in the same direction, or the phased array antenna 104 can be used to communicate with two different entities simultaneously.

[0033] Each of the J subarrays 108 transmits a subarray signal to the beamformer 112 such that there are J subarray signals. The beamformer 112 can be implemented as a plurality of beamforming networks (BFNs) or digital logic components (e.g., a field programmable gate array (FPGA)). In either case, the beamformer 112 can convert between the J subarray signals and K beam signals, where K is an integer greater than or equal to one. Each beam signal corresponds to one and only one (exactly one) beam.

[0034] Each of the K beam signals can be a transmit signal or a receive signal that includes embedded data. Each of the K beam signals can be transmitted to the K modems 116. The K modems 116 can be employed to encode or decode data on the corresponding beam signal of the K beam signals.

[0035] The multi-beam phased array antenna system 100 may include a controller 120 that can control the operation of a beamformer 112 and J sub-arrays 108 of the phased array antenna 104. In some examples, the controller 120 may be implemented as, for example, one or more processor cores with embedded instructions. In other examples, the controller 120 may be implemented as a computing platform, such as a system having a non-transitory machine-readable medium (e.g., memory) storing machine-readable instructions and one or more processor cores executing the machine-readable instructions.

[0036] As described, the multi-beam phased array antenna system 100 transmits multiple beams simultaneously. Each beam transmitted by the phased array antenna system 100 operates as either a transmit beam or a receive beam. In an example where a given beam is a given receive beam, energy is received at the radiating elements of the sub-array 108 and converted into an RF signal. As detailed below, a subgroup of one or more of the sub-arrays 108 is assigned by the controller 120 to the given receive beam. The sub-array beamforming circuits of each sub-array 108 in the subgroup adjust and combine their RF signals in response to beam weights from the controller 120 to form a corresponding sub-array signal associated with the given receive beam. Then the sub-array signals from each sub-array 108 in the subgroup are provided to the beamformer 112. In response to a control signal from the controller 120, the beamformer 112 adjusts and combines the sub-array signals from the subgroup to form a given receive beam signal (e.g., beam signal 1) corresponding to the given receive beam. One or more other subgroups of sub-arrays are similarly assigned by the controller 120 to each of the other receive beams, and beam weights are provided to form corresponding sub-array signals associated with the other assigned receive beams. The beamformer 112 similarly adjusts and combines a corresponding set of one or more sub-array signals associated with each of the other corresponding receive beams to form other receive beam signals. Then each of the K receive beam signals is provided to a given modem of the K modems 116. In response to the beam signal, the given modem 116 decodes the data on the beam signal for use at an external system.

[0037] Conversely, in an example where a given beam is a given transmit beam, a given modem 116 among the K modems 116 receives data for transmission from an external system. In response to the data, the given modem 116 encodes the data on a given beam signal among the K beam signals, and the given beam signal is provided to the beamformer 112. In response to a control signal, the beamformer 112 converts the given beam signal into a given set of one or more subarray signals associated with the given transmit beam. Then, the beamformer 112 provides each corresponding subarray signal in the given set to a corresponding subarray 108 in a subgroup of subarrays that have been determined by the controller 120 to be for the given transmit beam. In response to beam weights, the subarray beamforming circuitry of each subarray 108 in the subgroup converts the corresponding subarray signal into a set of RF signals. Each RF signal among these RF signals is propagated into free space as the given beam by a radiating element of each corresponding subarray 108 in the subgroup of subarrays 108, thereby forming the given transmit beam. The multi-beam phased array antenna system 100 similarly forms other transmit beams (if any).

[0038] The beamforming circuitry of the J subarrays 108 can be implemented as receive beamforming circuitry and / or transmit beamforming circuitry. The receive beamforming circuitry is assigned to receive beams (such as the given receive beam described above), and the transmit beamforming circuitry is assigned to transmit beams (such as the given transmit beam described above). Each instance of the beamforming circuitry includes active components (e.g., phase shifters and / or amplifiers) configured to adjust a particular type of signal in one direction. More particularly, the receive beamforming circuitry is configured to adjust and combine RF signals to form subarray signals associated with the receive beam that are subsequently provided to the beamformer 112. Conversely, the transmit beamforming circuitry is configured to obtain subarray signals associated with the transmit beam from the beamformer and divide and adjust the subarray signals into RF signals for transmission into free space.

[0039] The controller 120 can provide a control signal to the beamformer 112 that causes the beamformer 112 to assign individual subarrays 108 to a particular beam. In other words, in response to a control signal provided from the controller 120, the beamformer 112 assigns individual subarrays 108 to a particular beam. Additionally, the controller 120 can provide beam weights to the subarray beamforming circuitry of the J subarrays 108. In response to the beam weights, the subarray beamforming circuitry of each of the J subarrays 108 adjusts the corresponding RF signals for transmission on the corresponding radiating elements.

[0040] The beam weights provided by the controller 120 may be implemented as control signals that control the operation of each respective one of the J subarrays 108. The beam weights may control the operation of phase shifters, amplifiers, filters, switching devices, etc. of the subarray beamforming circuitry.

[0041] The beam weights provided to the subarrays 108 and the control signals provided from the controller 120 to the beamformer 112 define the beams to be transmitted (transmitted or received) by the radiating elements of the subarrays 108 via constructive and destructive interference of the energy focused in a particular direction. More particularly, the beam weights applied by each of the subarrays in the subarray 108 adjust (e.g., amplify and / or phase shift) the RF signals transmitted by each respective subarray 108 and the control signals used by the beamformer to condition the subarray signals associated with each beam such that the beams in turn focus the energy transmitted in a particular direction.

[0042] In operation, the controller 120 may determine two or more beams for communication from among a plurality of beams. The two or more beams may be determined, for example, based on the position of the multi-beam phased array antenna system 100 and the position of an external entity that communicates wirelessly with the multi-beam phased array antenna system 100. Determining the two or more beams includes operations performed by the controller 120 to determine the number of beams to be formed and the desired characteristics (e.g., beam width, gain, sidelobe level, cross polarization, etc.) of each of the two or more beams. More particularly, the controller 120 may be configured to weigh a plurality of factors to determine the number and characteristics of the beams in the two or more beams. These factors may include, but are not limited to: the identification of the entity (e.g., satellite) with which to communicate, the directionality of the communication with each entity (e.g., whether the communication is unidirectional (transmit or receive) or bidirectional (transmit and receive)), the position of each entity relative to the orientation of the phased array antenna 104, and the desired link performance between the phased array antenna 104, the entity, and / or possible interference levels in other directions. Additionally, in some examples, the controller 120 may determine the two or more beams by considering only a subgroup of these factors. In other examples, the controller 120 may determine the two or more beams by considering a superset of these factors.

[0043] Two or more of the plurality of beams determined by the controller 120 include at least two beams of the same communication type. That is, the two or more beams include at least two transmit beams or at least two receive beams. Two beams of the same communication type differ in at least one of their frequency, polarization, and pointing direction.

[0044] In some examples, the controller 120 can simultaneously determine a first receive beam for receiving data from a first entity (e.g., a first satellite) and a second receive beam for receiving data from a second entity (e.g., a second satellite), such that the multi-beam phased array antenna system 100 has two receive beams. Additionally or alternatively, in some examples, the controller 120 can determine a first transmit beam for transmitting data to a first entity and a second transmit beam for transmitting data to a second entity. In such cases, the multi-beam phased array antenna system 100 can simultaneously perform two-way communication with two different external entities (such as two different satellites). For example, one satellite can be a low-earth orbit satellite and the other satellite can be a geostationary orbit satellite. Alternatively, both satellites can be low-earth orbit satellites, or both satellites can be geostationary orbit satellites. In either such case, the controller 120 can simultaneously determine a first beam for transmitting data to the first satellite, a second beam for receiving data from the first satellite, a third beam for transmitting data to the second satellite, and a fourth beam for receiving data from the second satellite. In this example, the first beam and the second beam can have the same direction, and the third beam and the fourth beam can also have the same direction. This allows the multi-beam phased array antenna system 100 to achieve break-before-make communication with two satellites. More particularly, the controller 120 can determine the first beam and the second beam for communicating with the first satellite, and then determine the third beam and the fourth beam for communicating with the second satellite before losing communication with the first satellite.

[0045] In other examples, the multi-beam phased array antenna system 100 can communicate with three or more entities simultaneously. Additionally, in other examples, the controller 120 can be configured to communicate with a particular entity using only one beam (e.g., a transmit beam or a receive beam), such that the multi-beam phased array antenna system 100 transmits or receives data only with the particular entity to provide one-way communication.

[0046] In response to determining two or more beams from a plurality of beams, the controller 120 can allocate J non-overlapping subarray subgroups of the phased array antenna 104. For example, as shown, the controller 120 can allocate subarrays 1-3, 6-8, and 11 as a first non-overlapping subarray 108 subgroup to the first beam, and allocate subarrays 4-5, 9-10, and 13-14 as a second non-overlapping subarray 108 subgroup to the second beam. In the illustrated example, for illustrative purposes, the second non-overlapping subarray 108 subgroup has been shaded.

[0047] The assignment of the disjoint subarray 108 subgroups can be based on, for example, the characteristics of the beam transmitted to an external entity. Such characteristics of a given beam can include, for example, the aperture size and shape of the given beam. For example, certain subarrays 108 can be determined to account for the beamwidth and / or signal strength required for communication with an external entity.

[0048] The controller 120 can calculate the beam weights required for each individual subarray 108 based on the assignment. The beam weights can characterize the phase shift and / or amplification of the RF signals required for the characteristics (e.g., aperture size and shape) of a particular beam. In this example, different subarrays 108 within the same disjoint subgroup can have different beam weights. Additionally, different subarrays 108 in different disjoint subgroups can also have different beam weights. That is, the beam weight of each individual subarray 108 can be tuned for the particular beam to which the corresponding subarray 108 is assigned. The controller 120 can provide the beam weights to each of the J subarrays 108 in the phased array antenna 104. The corresponding subarray beamforming circuit of each subarray 108 can adjust the RF signals transmitted with the corresponding radiating elements in response to the beam weights provided from the controller 120. In other words, in response to the beam weights, the corresponding subarray beamforming circuit of each subarray can adjust the RF signals transmitted with the radiating elements accordingly.

[0049] The assignment of the subarrays 108 to a particular beam and / or the assignment of the beam weights can be dynamically changed by the controller 120. For example, the controller 120 can reassign some (or all) of the subarrays 108 to a new beam and / or recalculate the beam weights to: compensate for changes in the position of the entity accommodating the multi-beam phased array antenna system 100 and / or changes in the position of an external entity communicating with the multi-beam phased array antenna system 100 (e.g., a satellite); or comply with regulatory requirements.

[0050] In addition, in response to an allocation (or reallocation), the controller 120 provides a control signal to the beamformer 112. In response to the control signal, the beamformer 112 couples each subarray signal to a corresponding one of the K beam signals such that each subarray signal is a constituent component of one and only one beam signal. For example, in the presence of two beam signals (i.e., a first beam signal and a second beam signal), the subarray signal associated with the subarray 108 in the first non-overlapping subgroup may be coupled to the signal path for the first beam signal. Thus, the beamformer 112 can switch between the subarray signal associated with the subarray 108 in the first non-overlapping subgroup and the first beam signal. Similarly, in this case, the beamformer 112 couples the subarray signal associated with the second non-overlapping subgroup to the signal path associated with the second beamforming signal. Thus, the beamformer 112 can switch between the subarray signal associated with the subarray 108 in the second non-overlapping subgroup and the second beam signal.

[0051] As the position of the multi-beam phased array antenna system 100 changes and / or the position of an external entity changes, the controller 120 can determine different ones of the K beams and dynamically allocate subgroups of the non-overlapping subarrays 108 to the determined beams. In this way, the same phased array antenna 104 formed by the J subarrays 108 can be used to simultaneously transmit different beams. Thus, the multi-beam phased array antenna system 100 can establish communication with one or more entities via the determined beams.

[0052] A conventional multi-beam antenna may include circuitry that allows all radiating elements to contribute to each beam. However, such conventional multi-beam antennas are highly complex because they require a large number of circuit components and thus correspondingly increase the cost. In contrast, each of the J sub-arrays 108 includes a sub-array beamforming circuitry that can be used to contribute to one and only one beam (i.e., one and only one transmit beam and / or one and only one receive beam) for a particular communication type. That is, each of the J sub-arrays 108 includes a single instance of a beamforming sub-array circuit for a particular communication type (e.g., implemented as a combiner / divider network), which is a 1:G port device (where "1" corresponds to the sub-array signal and G is the number of RF signals processed by the beamforming sub-array circuit), and there is a set of G adjustment circuits that cause the sub-array radiating elements to contribute to one beam for a particular communication type. In an implementation where a given sub-array 108 includes radiating elements for both transmission and reception, the beamforming circuit of the given sub-array 108 may include a receive beamforming circuit (capable of being used to contribute to one and only one receive beam) and a transmit beamforming circuit (capable of being used to contribute to one and only one transmit beam). Although the multi-phase array antenna 100 may have lower performance metrics in some applications compared to conventional multi-beam antennas, the multi-phase array antenna 100 has lower cost and complexity compared to conventional multi-beam antennas. More particularly, Figure 1 the multi-phase array antenna 100 sacrifices performance only by using each of the J sub-arrays 108 for one beam in exchange for a significant cost savings / reduced complexity by having many smaller circuit elements.

[0053] Figure 2 A block diagram showing an example of a sub-array 200 that can be employed in a phased array antenna is presented. The sub-array 200 can be used to implement Figure 1 one of the J sub-arrays 108 of the phased array antenna 104.

[0054] The sub-array 200 includes G radiating elements 204, where G is an integer greater than one. Each of the G radiating elements 204 can be implemented as, for example, a patch antenna, a slot antenna, or a combination thereof. Each of the G radiating elements 204 can be employed to transmit an RF signal 206. In an example where the sub-array 200 is assigned to a transmit beam, each of the G radiating elements 204 transmits the RF signal 206 into free space. The RF signals 206 transmitted by the G radiating elements 204 can be horizontally polarized, vertically polarized, circularly polarized, etc. In an example where the sub-array 200 is assigned to a receive beam, each of the G radiating elements 204 receives the RF signal 206 from free space.

[0055] Each of the G radiating elements 204 communicates with a subarray beamforming circuit 208. The subarray beamforming circuit 208 may include beamforming circuits, phase shifters, amplifiers, combiners / splitters circuits, etc., to convert between the G RF signals 206 and the subarray signal 218. The subarray signal 218 may be communicated with a beamformer (such as Figure 1 beamformer 112). The subarray beamforming circuit 208 may include a port 214 for the subarray signal 218. In an illustrative example where the subarray 200 is used to facilitate a given beam (e.g., a transmit beam or a receive beam) for a particular communication type, the subarray 200 includes one and only one port for the subarray signal 218 such that the subarray beamforming circuit communicates one and only one subarray signal 218 associated with the given beam each time. In an example where the subarray 200 is used to facilitate a receive beam and a transmit beam, the subarray 200 includes two ports: one and only one port for the receive subarray signal associated with the receive beam and one and only one port for the transmit subarray signal associated with the transmit beam (see, for example Figure 16 ).

[0056] In the illustrative example, the subarray beamforming circuit 208 includes a subarray BFN 212. The subarray BFN 212 may include the subarray signal port 214 of the subarray beamforming circuit 208. The subarray beamforming circuit 208 also includes G adjustment circuits 216 that communicate corresponding RF signals 206 with the corresponding radiating elements 204. The G adjustment circuits 216 may each be implemented as discrete circuit components, IC chips (or multiple IC chips) (such as radio frequency integrated circuit (RFIC) chips), or a combination thereof. For example, in some examples, each adjustment circuit 216 may be implemented using an RFIC chip such that there is a one-to-one correspondence between the RFIC chip and the radiating element 204. In other examples, there may be other ratios of RFIC chips to radiating elements 204, including examples where multiple radiating elements 204 are connected to a single RFIC chip. In the illustrative example, each adjustment circuit 216 communicates an RF signal 206 to the corresponding radiating element 204. In this case, one RF signal 206 communicated with the corresponding radiating element 204 may be vertically polarized, and another signal communicated with the corresponding radiating element 204 may be horizontally polarized. In other examples, each adjustment circuit 216 may communicate a single RF signal 216 with the corresponding radiating element 204.

[0057] Additionally, the subarray BFN 212 conveys subarray component signals 218 to each of the adjustment circuits in the adjustment circuit 216. The subarray BFN 212 is configured to convert between the subarray signal 218 and the RF signal 206. Each of the G adjustment circuits 216 adjusts (e.g., amplifies and / or phase-shifts) the corresponding RF signal 206 conveyed by the corresponding radiating element 204. Accordingly, the subarray BFN 212 and the G adjustment circuits 216 cooperate to convert between the subarray signal 218 and the RF signals 206 conveyed by the G radiating elements 204.

[0058] The subarray 200 can contribute to a portion of a transmit beam and / or contribute to a portion of a receive beam. In an example where the subarray 200 contributes to a portion of a receive beam, energy is received at the G radiating elements 204 and converted into an RF signal 206. The subarray beamforming circuit 208 adjusts and combines the RF signals 206 and forms a subarray signal 218 provided to the beamformer. More particularly, in response to beam weights, each of the G adjustment circuits 216 adjusts the RF signal 206 and provides the corresponding adjusted RF signal 206 to the subarray BFN 212. In response to the adjusted RF signals 206, the subarray BFN 212 combines the adjusted RF signals 206 to provide the subarray signal 218 through the port 214.

[0059] In an example where the subarray 200 contributes to a portion of a transmit beam, the subarray beamforming circuit 208 receives the subarray signal 218 associated with the transmit beam from the beamformer. In response to the subarray signal, the beamforming circuit 208 converts the subarray signal into G RF signals 204. More particularly, the subarray BFN 212 receives the subarray signal 218 provided by the beamformer at the port 214. The subarray BFN 212 converts the subarray signal 218 into G RF signals 206 provided to the corresponding adjustment circuits 216. The adjustment circuits 216 adjust the corresponding RF signals 206 in response to beam weights and provide the corresponding RF signals 206 to the corresponding radiating elements 204, where each of the RF signals 206 is propagated into free space to contribute to the transmit beam.

[0060] The beamforming circuit 208 can be implemented as a receive beamforming circuit and / or a transmit beamforming circuit. In an example where the beamforming circuit 208 is implemented as a receive beamforming circuit, the beamforming circuit can be assigned to a receive beam (such as the receive beam described above). Conversely, in an example where the beamforming circuit 208 is implemented as a transmit beamforming circuit, the beamforming circuit 208 can be assigned to a transmit beam (such as the transmit beam described above). The G adjustment circuits 216 of the beamforming circuit 208 include active components (e.g., phase shifters and / or amplifiers) configured to adjust the RF signal 206 in one direction. More particularly, the receive beamforming circuit 208 is configured to adjust and combine the RF signal 206 to form a subarray signal 218 associated with the receive beam. Conversely, the transmit beamforming circuit is configured to divide and adjust the subarray signal 218 associated with the transmit beam into the RF signal 216 for transmission into free space to facilitate the transmit beam.

[0061] The subarray beamforming circuit 208 can adjust the RF signal 206 based on beam weights 220 provided from a controller (such as Figure 1 controller 120). More particularly, the beam weights 220 can be provided to each of the G adjustment circuits 216. Each of the G adjustment circuits 216 can include active components and / or other circuits that can adjust the RF signal 206. For example, each adjustment circuit 216 can include an amplifier and / or a phase shifter that can be used to amplify and / or phase-shift the RF signal 206 transmitted by the corresponding radiating element 204, respectively. The amount of amplification and / or phase-shifting is controlled by the beam weights 220. In other words, in response to the beam weights 220, each adjustment circuit 216 amplifies and / or phase-shifts the RF signal 206 transmitted by the corresponding radiating element 204.

[0062] In some examples, the subarray BFN 212 is a passive 1:G circuit that includes a combiner / divider that combines or divides one of the subarray signals 218 into the RF signal 206 for adjustment by the G adjustment circuits 216. More particularly, in one example, a combiner / divider can be employed to combine the RF signals 206 provided from the adjustment circuits 216 into the subarray signal 218. In other examples, the combiner / divider of the subarray BFN 212 can divide the subarray signal 218 into the RF signals 206 provided to the adjustment circuits 216. Although the subarray 200 is shown as separate adjustment circuits 216 from the subarray BFN 212, in some examples, the adjustment circuits 216 can be integrated with the subarray BFN 212.

[0063] As shown, it can be determined that the beam weights 220 provided from the controller are used to individually tune the RF signals 206 transmitted by the G radiating elements 204. That is, in response to the beam weights 220, the subarray beamforming circuit 208 adjusts the RF signals 206 accordingly, such that the subarray 200 can cooperate with other subarrays (e.g., other subarrays determined for a specific beam in a non-overlapping subgroup) to transmit a beam in free space.

[0064] As shown, the subarray 200 (which represents Figure 1 any one of the J subarrays 108) just has one instance of the beamforming circuit 208 for a specific communication type. In addition, the subarray beamforming circuit 208 is a 1:G port device. More particularly, the port 214 corresponds to "1", and G corresponds to the number G of RF signals 206 transmitted by the G adjustment circuits 216. In addition, as shown, the subarray beamforming circuit 208 includes just a set of G adjustment circuits 216, such that the components of the subarray 208 contribute to one and only one beam of a specific communication type. In contrast, a conventional multi-beam phased array antenna that uses each radiating element for each of the M beams has 2*M 1:X port devices (where X is the total number of radiating elements in the array) and a total of M*X adjustment circuits (a set of X adjustment circuits for each beam). Although using one radiating element for each beam can provide good performance (due to using the entire antenna aperture), the conventional multi-beam antenna also has higher cost and complexity than Figure 1 the multi-beam phased array antenna 100 that employs J subarrays 200. Therefore, compared with the conventional multi-beam antenna, the Figure 1 multi-phase phased array antenna 100 that uses J subarrays 200 may have a lower performance metric, but Figure 1 the multi-phase phased array antenna 100 has lower cost and complexity. More particularly, by providing the subarray 200 as a 1:G port device and the G adjustment circuits 216 that contribute to one and only one beam, the Figure 1 multi-phase phased array antenna 100 that uses J subarrays 200 can (by having many smaller circuit elements) achieve a significant cost savings / reduced complexity compared to a conventional phased array antenna.

[0065] Figure 3 An example of a multi-beam phased array antenna system 300 including a beamformer 302 implemented using analog circuits is shown. The multi-beam phased array antenna system 300 can be employed to implement Figure 1 the multi-beam phased array antenna system 100. Thus, the multi-beam phased array antenna system 300 transmits multiple beams simultaneously. The beamformer 302 can be used to implement Figure 1beamformer 112. In addition, the multi-beam phased array antenna system 300 includes a phased array antenna 304 that can be employed to implement Figure 1 phased array antenna 104. Thus, J subarrays 308 (such as Figure 1 J subarrays 108) can be utilized to form phased array antenna 304. In addition, each of the J subarrays 308 of phased array antenna 304 can be implemented using an example of subarray 200 of Figure 2 . In some examples, phased array antenna 304 can represent multiple antennas (e.g., transmit antennas and receive antennas). More particularly, in some examples, phased array antenna 304 can represent multiple contiguous separated portions of J subarrays 308 that form separate antennas. Such contiguous separated portions of J subarrays 308 that form separate antennas can be spaced apart from each other. Additionally, these contiguous separated portions of J subarrays 308 can be used to operate independently (e.g., one phased array antenna for a receive beam and another phased array antenna for a transmit beam). In other examples, phased array antenna 304 represents a single antenna. In this case, J subarrays 308 can be arranged in a contiguous pattern, and different subarrays 308 of J subarrays 308 can be assigned to different beams.

[0066] Each of the J subarrays 308 includes a subarray beamforming circuit that converts between RF signals and subarray signals such that phased array antenna 304 conveys J subarray signals to beamformer 302. As described, beamformer 302 is implemented using analog circuitry. More particularly, beamformer 302 can include K BFNs 312. Each of the K BFNs 312 can convert between a subgroup of the J subarray signals and one and only one particular beam signal of the K beam signals. Each beam signal corresponds to one and only one beam.

[0067] Each of the K beam signals can be either a transmit signal or a receive signal that includes embedded data at a given time during operation of the multi-beam phased array antenna system 300. More particularly, the multi-beam phased array antenna system 300 can be configured to switch the assignment of beam signals between transmit signals and receive signals. Each of the K beam signals can be conveyed to a modem 116 among the K modems 316. The K modems 316 can be employed to encode or decode data on the corresponding beam signal of the K beam signals.

[0068] The beamformer 302 may include J switching devices 320. Each of the J switching devices 320 may be coupled to one and only one of the J sub-arrays 308. Each of the J switching devices 320 may be implemented as a single-pole multi-throw switching device configured to electrically couple a corresponding one of the J sub-arrays 308 to a determined one of the K BFNs 312. That is, at any given time point, each of the J switching devices 320 may be coupled to a corresponding sub-array 308 and to any one of the K BFNs 312. Each of the J switching devices 320 may be implemented as a transistor-based solid-state switching device or an electromechanical switching device.

[0069] The multi-beam phased array antenna system 300 may include a controller 324 that may control the operation of the beamformer 302 and the J sub-arrays 308 of the phased array antenna 304. In some examples, the controller 324 may be employed to implement Figure 1 the controller 120. The controller 324 may provide control signals to the beamformer that cause the beamformer 302 to allocate individual sub-arrays 308 to specific beams. Additionally, the controller 324 may provide beam weights to the sub-array beamforming circuits of the J sub-arrays 308. In response to the beam weights, the sub-array beamforming circuits of each of the J sub-arrays 108 may adjust the corresponding RF signals for transmission on the corresponding radiating elements.

[0070] Further, the control signals provided by the controller 324 may control the states of the J switching devices 320. In other words, the state of each of the J switching devices 320 is responsive to the control signals provided from the controller 324. Thus, in response to the control signals, each of the J switching devices 320 couples the corresponding sub-array 308 of the J sub-arrays 308 to the determined BFN 312 of the K BFNs 312. In this way, each of the J sub-arrays 308 is electrically coupled to one and only one BFN 312.

[0071] In operation, the controller 324 may determine two or more beams from a plurality of beams. The two or more determined beams include two beams of the same communication type (e.g., at least two receive beams or at least two transmit beams). The two or more beams may be determined, for example, based on the position of the multi-beam phased array antenna system 300 and the position of an external entity that communicates wirelessly with the multi-beam phased array antenna system 300. Additionally or alternatively, in some examples, the controller 120 may determine four (4) beams from the plurality of beams to establish two-way communication with two different entities (e.g., two different satellites). This allows the multi-beam phased array antenna system 300 to achieve break-before-make communication with two satellites.

[0072] In other examples, the multi-beam phased array antenna system 300 may communicate with three or more satellites simultaneously. Additionally, in other examples, the controller 324 may be configured to communicate with a particular satellite using only one beam, such that the multi-beam phased array antenna system 300 transmits or receives data (one-way communication) only with the particular satellite.

[0073] In response to determining two or more beams from the plurality of beams, the controller 324 may assign a subgroup of J non-overlapping subarrays 308 of the phased array antenna 304 to the two or more determined beams. The assignment of the subgroup of non-overlapping subarrays 308 may be based on, for example, the characteristics (aperture size and shape) of the beams transmitted to the external entity.

[0074] The controller 324 may calculate the beam weights required for each individual subarray 308 based on the assignment. The beam weights may characterize the phase shift and / or amplification of the RF signals required for the characteristics (e.g., aperture size and shape) of a particular beam. The beam weights applied by each subarray in the subarray 308 adjust (e.g., amplify and / or phase shift) the RF signals transmitted by each corresponding subarray 308 and the control signals used by the beamformer 302 to condition the subarray signals associated with each beam, such that the beams in turn focus the energy transmitted in a particular direction. The assignment of the subarray 308 to a particular beam and / or the assignment of the beam weights may be changed dynamically by the controller 324. For example, the controller 324 may reassign some (or all) of the subarrays in the subarray 308 to a new beam and / or recalculate the beam weights to: compensate for changes in the position of the entity housing the multi-beam phased array antenna system 300 and / or changes in the position of an external entity communicating with the multi-beam phased array antenna system 300 (e.g., a satellite); or comply with regulatory requirements.

[0075] Additionally, in response to the allocation, the controller 324 provides control signals to the beamformer 302. More particularly, the controller provides control signals to each of the J switching devices 320. In response to the control signals, each of the switching devices 320 electrically couples a respective one of the J subarrays 308 to a particular BFN 312 among the K BFNs 312.

[0076] In some examples, each BFN among the K BFNs 312 (or a subgroup thereof) may include a phase shifter 328. Each phase shifter 328 may adjust the phase of each subarray signal transmitted by the subgroup of switching devices 320 coupled thereto. For example, if the first BFN 312 (BFN 1) is coupled to the first switching device and the Jth switching device 320 (switching device 1 and switching device J), the phase shifter 328 of the first BFN 312 may phase-shift the first subarray signal transmitted by the first subarray 308 and the Jth subarray signal transmitted by the Jth subarray 308.

[0077] Each phase shifter 328 among the K BFNs 312 may apply a phase shift based on the control signal. In other words, in response to the control signal provided from the controller 324, each phase shifter 328 shifts the phase of a subgroup of the J subarray signals. Thus, the control signal provided from the controller 324 may control the states of each of the J switching devices 320 and each of the phase shifters 328 of each BFN among the BFNs 312.

[0078] By implementing the beamformer 302 as having analog circuitry (i.e., J switching devices and K BFNs 312), a relatively simple and low-power multi-beam phased array antenna system 300 can be provided. Additionally, as shown, the K BFNs 312 cooperate with the J switching devices to facilitate simultaneous communication on at least two beams.

[0079] Figure 4 An example of a multi-beam phased array antenna system 400 including a beamformer 402 having digital circuitry is shown. The multi-beam phased array antenna system 400 can be employed to implement Figure 1 the multi-beam phased array antenna system 100. Thus, the multi-beam phased array antenna system 400 simultaneously transmits multiple beam signals. The beamformer 402 can be used to implement Figure 1 the beamformer 112. Additionally, the multi-beam phased array antenna system 300 includes a phased array antenna 404 that can be employed to implement Figure 1 the phased array antenna 104. Thus, J subarrays 408 (such as Figure 1 the J subarrays 108) can be utilized to form the phased array antenna 504. Additionally, Figure 2An example of the sub-array 200 is used to implement each of the J sub-arrays 408 of the phased array antenna 404. In some examples, the phased array antenna 404 may represent multiple antennas (e.g., transmit antennas and receive antennas). In other examples, the phased array antenna 404 represents a single antenna.

[0080] Each of the J sub-arrays 408 includes a sub-array beamforming circuit that converts between RF signals and sub-array signals, such that the phased array antenna 404 transmits the J sub-array signals to the beamformer 402. As described, the beamformer 402 is implemented using digital circuitry. More particularly, the beamformer 402 may include digital logic components 412. The digital logic components 412 may be implemented as, for example, an FPGA or implemented as an application specific integrated circuit (ASIC) chip. In other examples, the digital logic components 412 may be implemented as a controller that provides a computing platform to implement a virtual gate array. The digital logic components 412 may include logic gates for converting between K beam signals and J digital sub-array signals.

[0081] Each of the K beam signals may be a transmit signal or a receive signal that includes embedded data. Each of the K beam signals may be transmitted to a modem 416 among the K modems 416. The K modems 416 may be employed to encode or decode data on the corresponding beam signal among the K beam signals.

[0082] The beamformer 402 may include J digital-to-analog converters (DACs) 420. Each of the J DACs 420 may be coupled to each of the J sub-arrays 408 and the digital logic components 412. Each of the J DACs 420 may convert between digital sub-array signals and (analog) sub-array signals. In some examples, each of the DACs 420 may convert a corresponding digital sub-array signal to a digital signal corresponding to an analog version of the sub-array signal provided to the corresponding sub-array 408. In other examples, each of the DACs 420 may convert a sub-array signal provided from the corresponding sub-array 408 to a digitized version of the sub-array signal and provide the corresponding digital sub-array signal to the digital logic components 412. In other examples, the DAC 420 may convert the corresponding digital sub-array signal to the corresponding sub-array signal and convert the corresponding sub-array signal to the corresponding digital sub-array signal.

[0083] The multi-beam phased array antenna system 400 may include a controller 424 that may control the operation of the beamformer 402 and the J sub-arrays 408 of the phased array antenna 404. In some examples, the controller 424 may be employed to implement Figure 1Controller 120. Controller 424 may provide control signals to beamformer 402 that cause beamformer 402 to allocate individual subarrays 408 to specific beams. Additionally, controller 424 may provide beam weights to the subarray beamforming circuits of the J subarrays 408. In response to the beam weights, the subarray beamforming circuits of each of the J subarrays 408 may adjust the respective RF signals for transmission on the respective radiating elements.

[0084] More particularly, the control signals provided by controller 424 may be provided to digital logic component 412 of beamformer 402. In response to the control signals, digital logic component 412 may establish signal paths between the respective beam signals and the respective digital subarray signals coupled to one of the J DACs 420. The signal paths provide phase delays, combinations, and / or frequency divisions for converting between the respective beam signals and the digital subarray signals. Similarly, each of the J DACs 420 responds to control signals provided from controller 424. For example, each of the DACs 420 may apply beam weights (amplification and / or phase shift) to digital subarray circuits that communicate with digital logic component 412.

[0085] In operation, controller 424 may determine two or more beams from a plurality of beams. The two or more determined beams include two beams of the same communication type (e.g., at least two receive beams or at least two transmit beams). The two or more beams may be determined, for example, based on the position of multi-beam phased array antenna system 400 and the position of an external entity that communicates wirelessly with multi-beam phased array antenna system 400. Additionally or alternatively, in some examples, controller 424 may determine four (4) beams from a plurality of beams to establish two-way communication with two different entities (e.g., two different satellites). This allows multi-beam phased array antenna system 400 to implement break-before-make communication with two satellites.

[0086] In other examples, multi-beam phased array antenna system 400 may communicate with three or more satellites simultaneously. Additionally, in other examples, controller 424 may be configured to communicate with a specific satellite using only one beam such that multi-beam phased array antenna system 400 transmits or receives data (one-way communication) only with the specific satellite.

[0087] In response to determining two or more beams from a plurality of beams, controller 424 may allocate sub-groups of the J non-overlapping subarrays 408 of phased array antenna 404 to the two or more determined beams. The allocation of the non-overlapping subarray 408 sub-groups may be based, for example, on the characteristics (aperture size and shape) of the beams transmitted to the external entity.

[0088] The controller 424 can calculate the beam weights required for each individual sub - array 408 based on the assignment. The beam weights can characterize the phase shift and / or amplification of the RF signals required for the characteristics of a particular beam (e.g., aperture size and shape). The beam weights applied by each of the sub - arrays in the sub - array 408 adjust (e.g., amplify and / or phase - shift) the RF signals transmitted by each corresponding sub - array 408 and the control signals used by the beamformer 402 to condition the sub - array signals associated with each beam, such that the beam in turn focuses the energy transmitted in a particular direction. The assignment of sub - arrays to a particular beam and / or the assignment of beam weights can be changed dynamically by the controller 424. For example, the controller 424 can re - assign some (or all) of the sub - arrays in the sub - array 408 to a new beam and / or re - calculate the beam weights to: compensate for position changes of the entity housing the multi - beam phased - array antenna system 400 and / or position changes of an external entity communicating with the multi - beam phased - array antenna system 400 (e.g., a satellite); or comply with regulatory requirements.

[0089] Additionally, in response to the assignment, the controller 424 provides control signals to the beamformer 402. More particularly, the controller provides control signals to each of the digital logic components 412 and the J DACs 420. In response to the control signals, the digital logic component 412 provides a signal path between the corresponding digital sub - array signals and the corresponding beam signal among the K beam signals. As an example, the digital logic component 412 can associate a first group of sub - array signals with the first beam among the determined two or more beams, and associate a second subgroup of sub - array signals with the second beam among the determined two or more beams of the multiple beams. Additionally, in response to the control signals, each of the J DACs 420 can apply the beam weights to the corresponding digital sub - array signals and convert between the corresponding digital sub - array signals and the corresponding sub - array signals transmitted by the corresponding sub - arrays 408 of the phased - array antenna 404.

[0090] By implementing the beamformer 402 as a digital circuit (including the digital logic component 412), a simple and dynamic multi - beam phased - array antenna system 400 is provided. In particular, the K beam signals supported by the digital logic component 412 can be changed dynamically (e.g., by re - configuring the digital logic component 412). Thus, the multi - beam phased - array antenna system 400 can be adapted to change its operation over time without changing hard - wired circuitry.

[0091] Figure 5 An example of a multi - beam phased - array antenna system 500 including a beamformer 502 implemented using multiple IC chips is shown. The multi - beam phased - array antenna system 500 can be employed to implement Figure 1The multi-beam phased array antenna system 100 is a multi-beam phased array antenna system 500. Therefore, the multi-beam phased array antenna system 500 transmits multiple beam signals simultaneously. The beamformer 502 can be used to implement Figure 1 In addition, the multi-beam phased array antenna system 300 includes a beam former 112 that can be implemented using Figure 1 The phased array antenna 504 of the phased array antenna 104. Therefore, J subarrays 508 (such as Figure 1 The J sub-arrays 108) are used to form a phased array antenna 504. In addition, Figure 2 Each of the J subarrays 508 of the phased array antenna 504 is implemented as an instance of the subarray 200 of the phased array antenna 504. In some examples, the phased array antenna 504 can represent multiple antennas (e.g., a transmit antenna and a receive antenna). In other examples, the phased array antenna 504 represents a single antenna.

[0092] Each of the J subarrays 508 may include a subarray beamforming circuit that converts between RF signals and subarray signals so that the phased array antenna 504 transmits the J subarray signals to the beamformer 502. As described, the beamformer 502 is implemented using multiple IC chips. More specifically, the beamformer 502 may include J interconnected beam switching circuits 512, wherein each of the J interconnected beam switching circuits 512 is coupled to one and only one subarray in the subarray 508. In some examples, each of the J beam switching circuits 512 can be implemented as an ASIC or a controller with embedded instructions. In other examples, each of the J beam switching circuits 512 can be implemented using discrete circuit components. In the illustrated example, the J beam switching circuits 512 are arranged in a daisy chain to allow each of the J beam switching circuits 512 to communicate. In other examples, each of the J beam switching circuits 512 can communicate on a communication bus of the beamformer 502 .

[0093] Each of the J beam switching circuits 512 may switch between a corresponding subarray signal and the K beam signals. Each of the K beam signals may be a transmit signal or a receive signal including embedded data. Each of the K beam signals may be transmitted to a modem 516 in the K modems 516. The K modems 516 may be used to encode or decode data on a corresponding beam signal in the K beam signals.

[0094] In the illustrated example, each of the K modems 516 communicates with the first beam switching circuit 512 (beam switching circuit 1). In this case, the first beam switching circuit 512 may relay the beam signal to other beam switching circuits 512. In other examples, each of the K modems 516 may communicate with the beam switching circuit 512 via a communication bus. Each of the J beam switching circuits 512 may include an internal DAC (or other circuitry) that converts between the K beam signals and the subarray signals.

[0095] The multi-beam phased array antenna system 500 may include a controller 524 that may control the operation of the beamformer 502 and the J subarrays 508 of the phased array antenna 504. In some examples, the controller 524 may be employed to implement Figure 1 controller 120. The controller 524 may provide a control signal to the beamformer 502 that causes the beamformer 502 to allocate individual subarrays 508 to a particular beam. Additionally, the controller 524 may provide beam weights to the subarray beamforming circuitry of the J subarrays 508. In response to the beam weights, the subarray beamforming circuitry of each of the J subarrays 508 may adjust the respective RF signals for transmission on the corresponding radiating elements.

[0096] More particularly, the control signal provided by the controller 524 may provide a control signal to the J beam switching circuits 512 of the beamformer 502. In response to the control signal, the J beam switching circuits 512 may establish a signal path between the corresponding beam signal and the corresponding digital subarray signal coupled to one of the J beam switching circuits 512. The signal path may provide phase delay, combination, and / or frequency division for converting between the corresponding beam signal and the subarray signal.

[0097] In operation, the controller 524 may determine two or more beams from a plurality of beams. The two or more determined beams include two beams of the same communication type (e.g., at least two receive beams or at least two transmit beams). The two or more beams may be determined, for example, based on the location of the multi-beam phased array antenna system 500 and the location of an external entity that communicates wirelessly with the multi-beam phased array antenna system 500. Additionally or alternatively, in some examples, the controller 524 may determine four (4) beams from a plurality of beams to establish two-way communication with two different entities (e.g., two different satellites). This allows the multi-beam phased array antenna system 500 to implement make-before-break communication with two satellites.

[0098] In other examples, the multi-beam phased array antenna system 500 can communicate with three or more satellites simultaneously. Additionally, in other examples, the controller 524 can be configured to communicate with a particular satellite using only one beam, such that the multi-beam phased array antenna system 500 transmits or receives data only with the particular satellite (one-way communication).

[0099] In response to determining two or more beams from the plurality of beams, the controller 524 can assign a subgroup of J non-overlapping sub-arrays 508 of the phased array antenna 504 to the determined two or more beams. The assignment of the subgroup of non-overlapping sub-arrays 508 can be based on, for example, characteristics (aperture size and shape) of the beams transmitted to an external entity.

[0100] The controller 524 can calculate the beam weights required for each individual sub-array 508 based on the assignment. The beam weights can characterize the phase shift and / or amplification of the RF signals required for the characteristics (e.g., aperture size and shape) of a particular beam. The beam weights applied by each of the sub-arrays 508 in the sub-array 508 adjust (e.g., amplify and / or phase shift) the RF signals transmitted by each corresponding sub-array 508 and the control signals used by the beamformer 502 to condition the sub-array signals associated with each beam, such that the beams in turn focus the energy transmitted in a particular direction. The assignment of sub-arrays to a particular beam and / or the assignment of beam weights can be changed dynamically by the controller 524. For example, the controller 524 can reassign some (or all) of the sub-arrays 508 in the sub-array 508 to a new beam and / or recalculate the beam weights to: compensate for a change in the position of the entity housing the multi-beam phased array antenna system 500 and / or a change in the position of an external entity communicating with the multi-beam phased array antenna system 500 (e.g., a satellite); or comply with regulatory requirements.

[0101] Additionally, in response to the assignment, the controller 524 provides control signals to the beamformer 502. More particularly, the controller provides control signals to the J beam switching circuits 512. In response to the control signals, each of the J beam switching circuits 512 in the J beam switching circuits 512 provides a signal path between the corresponding sub-array signal and the corresponding beam signal among the K beam signals. Additionally, in response to the control signals, each of the J beam switching circuits 512 in the J beam switching circuits 512 can apply the beam weights to the corresponding digital sub-array signals and convert between the corresponding digital sub-array signals and the corresponding sub-array signals transmitted by the corresponding sub-arrays 508 of the phased array antenna 504.

[0102] A simple and dynamic multi-beam phased array antenna system 500 is provided by implementing the beamformer 502 with J beam switching circuits 512. In particular, the K beam signals supported by the J beam switching circuits 512 can be dynamically changed (e.g., by reconfiguring each of the J beam switching circuits 512). Thus, the multi-beam phased array antenna system 500 can be adapted to change its operation over time without changing the hardwired circuitry.

[0103] Figures 6 to 8 An example of a phased array antenna 600 that simultaneously transmits two beams is shown. The phased array antenna 600 can be used to implement Figure 1 the phased array antenna 104. The phased array antenna 600 includes twelve subarrays 604 labeled SA-1, …, SA-12. In other examples, there may be more or fewer subarrays 604. Each subarray 604 can be implemented using Figure 2 the subarray 200.

[0104] Figure 6 An example 608 is shown where the phased array antenna 600 communicates with a low Earth orbit (LEO) satellite 610 via a first beam in a first direction 614 and communicates with a geostationary Earth orbit (GEO) satellite 620 via a second beam in a second direction 624. In Figure 6 the example illustrated, subarrays 8-12 (SA-8, …, SA-12) are assigned to communicate on the first beam and in the first direction 614, and subarrays 1-7 (SA-1, …, SA-7) are assigned to communicate on the second beam in the second direction 624. In Figure 6 the example 608, it is assumed that the first direction 614 and the second direction 624 are opposite (or nearly opposite) directions. For illustrative purposes, a first line 626 perpendicular to the first direction 614 is included, and a second line 628 perpendicular to the second direction 624 is also included. In Figure 6 the example 608 illustrated, more subarrays 604 are assigned to the second beam to communicate with the GEO satellite 620 than the subarrays 604 assigned to the first beam to communicate with the LEO satellite 610. In some examples, more subarrays 604 can be assigned to the second beam to communicate with the GEO satellite 620 to compensate for the GEO satellite 620 being farther from the phased array antenna 600 than the LEO satellite 610.

[0105] Figure 7 An example 650 is shown where the phased array antenna 600 communicates with an LEO satellite 654 via a first beam in a first direction 658 and communicates with a GEO satellite 662 via a second beam in a second direction 668. In Figure 7In Example 650 illustrated in [reference], sub-arrays 9-12 (SA-8, …, SA-12) are assigned to communicate on the first beam and in the first direction 658, and sub-arrays 1-8 (SA-1, …, SA-8) are assigned to communicate on the second beam in the second direction 624. For illustrative purposes, a first line 670 perpendicular to the first direction 658 is included, and a second line 672 perpendicular to the second direction 668 is also included. In Figure 7 In Example 650 illustrated in [reference], more sub-arrays 604 are assigned to the second beam to communicate with the GEO satellite 662 than the sub-arrays 604 assigned to the first beam to communicate with the LEO satellite 654 (e.g., to compensate for the distance of the GEO satellite 662 relative to the LEO satellite 654).

[0106] Figure 8 Example 680 is shown, where the phased array antenna 600 communicates with the LEO satellite 684 via a first beam in a first direction 686 and communicates with the GEO satellite 688 via a second beam in a second direction 690. In Example 680, it is assumed that the first direction 686 and the second direction 690 are almost the same direction. Additionally, as Figure 8 shown, sub-arrays 8-12 (SA-8, …, SA-12) are assigned to communicate on the first beam and in the first direction 686, and sub-arrays 1-8 (SA-1, …, SA-8) are assigned to communicate on the second beam in the second direction 690. For illustrative purposes, a first line 692 perpendicular to the first direction 686 is included, and a second line 694 perpendicular to the second direction 690 is also included. In Figure 8 In Example 680 illustrated in [reference], more sub-arrays 604 are assigned to the second beam to communicate with the GEO satellite 688 than the sub-arrays 604 assigned to the first beam to communicate with the LEO satellite 684 (e.g., to compensate for the distance of the GEO satellite 688 relative to the LEO satellite 684).

[0107] As Figures 6 to 8 shown, the phased array antenna 600 can communicate with different satellites simultaneously using multiple beams. Additionally, as Figures 1 to 5 shown, the Figures 6 to 8 phased array antenna 600 can be dynamically changed to change the direction of the beam.

[0108] Figure 9 Shown is a phased array antenna (such as Figure 1Exemplary graph 900 of the on-axis gain-noise temperature (in decibels per kelvin (dB / K)) of different numbers of subarrays for two beam assignments of phased array antenna 104). In the example illustrated in graph 900, the phased array antenna includes 20 subarrays, and each subarray is assigned to one of two beams. Graph 900 shows that the performance of the beam can be changed by varying the number of subarrays assigned. As shown in graph 900, the more subarrays assigned to a particular beam (beam 1 or beam 2), the higher the performance of the particular beam.

[0109] Figures 10 to 12 An example of a multi-beam phased array antenna system 1000 including a first phased array antenna 1004 and a second phased array antenna 1008 is shown. The first phased array antenna 1004 may be configured as a transmitting antenna for transmitting a beam to an external entity (such as a satellite). The second phased array antenna 1008 may be configured as a receiving antenna for receiving a beam transmitted from an external entity (such as a satellite). Thus, in some examples, the first phased array antenna 1004 may be employed to transmit a beam to a given satellite, and the second phased array antenna 1008 may be employed to receive a beam from the given satellite. In this way, the multi-beam phased array antenna system 1000 allows for two-way communication with a given satellite.

[0110] Each of the phased array antenna 1004 and the phased array antenna 1008 may be employed to implement Figure 1 the phased array antenna 104. In the illustrated example, the first phased array antenna 1004 and the second phased array antenna 1008 are spaced apart from each other. In other examples, the first phased array antenna 1004 and the second phased array antenna 1008 may be superimposed on each other such that the radiating elements of the subarrays for transmission are located in a first region that at least partially overlaps a second region containing the radiating elements of the subarrays for reception.

[0111] The first phased array antenna 1004 includes a plurality of diamond-shaped subarrays 1012, and only one of these diamond-shaped subarrays is marked. Each of the diamond-shaped subarrays 1012 may be employed to implement Figure 2 an instance of the subarray 200. The second phased array antenna 1008 includes a plurality of hexagonal subarrays 1020 and a plurality of diamond-shaped subarrays 1024, and only one subarray of each of the hexagonal subarrays and the diamond-shaped subarrays is marked. Each of the hexagonal subarrays 1020 and the diamond-shaped subarrays 1024 of the second phased array antenna 1008 may also be employed to implement Figure 2 an instance of the subarray 200.

[0112] Subgroups of multiple rhombus - non - intersecting sub - arrays 1012 of the first phased - array antenna 1004 can be assigned to transmit (receive) different beams. Similarly, subgroups of multiple hexagon - non - intersecting sub - arrays 1020 and rhombus - non - intersecting sub - arrays 1024 of the second phased - array 1008 can be assigned to transmit (transmit) different beams.

[0113] Figure 10 An example 1030 is shown, where the multi - beam phased - array antenna system 1000 includes two phased - array antennas each transmitting two or more beams. More particularly, in example 1030, sub - arrays of the first phased - array antenna 1004 are assigned to three different receive beams, namely beam 1, beam 2, and beam 3. Additionally, in example 1030, sub - arrays of the second phased - array antenna 1008 are assigned to transmit beams, namely beam 4 and beam 5. Alternatively, the sub - arrays assigned to each beam and the number of transmit and / or receive beams can be different from this example. Figure 10 Includes a legend identifying the beams to which the individual rhombus sub - arrays 1012 of the first phased - array antenna 1004 and the hexagon sub - arrays 1020 and rhombus sub - arrays 1024 of the second phased - array antenna 1008 are assigned. In Figure 10 the example, the two phased - array antennas 1004 and 1008 are arranged separately such that

[0114] Figure 11 Another example 1050 is shown, where, with different assignments of non - intersecting sub - arrays, the multi - beam phased - array antenna system 1000 communicates with five beams simultaneously. Figure 12 Yet another example 1070 is shown, where, with different assignments of non - intersecting sub - arrays, the multi - beam phased - array antenna system 1000 communicates with five beams simultaneously.

[0115] As Figures 10 to 12 shown, the same multi - beam phased - array antenna system 1000 can be employed to communicate on multiple beams simultaneously. Additionally, the assignment of sub - arrays (e.g., the rhombus sub - arrays 1012 of the first phased - array antenna 1004 and the hexagon sub - arrays 1020 and rhombus sub - arrays 1024 of the second phased - array antenna 1008) can be dynamically assigned to control the pointing direction, performance, and aperture shape of the beams transmitted by the multi - beam phased - array antenna system 1000.

[0116] Figure 13 Shows a block diagram of a sub - array 1300 for a phased - array antenna, which depicts one of the J sub - arrays 108 operating in the receive mode and / or Figure 1 in Figure 2The logical interconnection of the subarray 200. The subarray 1300 can be dynamically assigned to a specific beam among multiple beams. Additionally, the subarray 1300 can be employed to provide the received subarray signal 1302 to a beamformer. The beamformer can be implemented using the architecture of the beamformer 112 of Figure 1 the beamformer 112, Figure 3 the beamformer 302, or Figure 4 the beamformer 402 of

[0117] In the illustrated example, G radiating elements 1304 communicate with a subarray beamforming circuit 1308. The subarray beamforming circuit 1308 may include G RFIC chips 1312 and a receive (RX) subarray BFN circuit 1316. Each of the G RFIC chips 1312 can be coupled to a corresponding radiating element 1304. Each of the RFIC chips 1312 in the RFIC chips 1312 adjusts the received RF signal 1314 and provides the adjusted RF signal 1314 to the RX subarray BFN circuit 1316. The RX subarray BFN circuit 1316 can be employed to implement the subarray BFN 212. The RX subarray BFN circuit 1316 can be coupled to the beamformer. The RX subarray BFN circuit 1316 can combine the G RF signals 1314 from the G RFIC chips 1312 to form the received subarray signal 1302. The received subarray signal 1302 can be provided to the beamformer. The RX subarray BFN circuit may include a port 1318 coupled to the beamformer. The RX subarray BFN circuit 1316 can provide the received subarray signal 1302 to the beamformer through the port 1318.

[0118] In the illustrated example, each RFIC chip 1312 may include an amplifier 1320 and a phase shifter 1324. The G RFIC chips 1312 can receive beam weights 1326 from a controller 1328, and the controller can be implemented using the controller 120 of Figure 1 The beam weights 1326 can be calculated by the controller 1328 based on the beam to which the subarray 1300 is assigned. In some examples, the beam weights 1326 can control the gain of each amplifier 1320 and / or the phase shift imposed by each phase shifter 1324. Thus, in some examples, each amplifier 1320 can be implemented as a variable gain amplifier, a switched attenuator circuit, etc.

[0119] In operation, the signals received by each of the G radiation elements 1304 (or a subgroup thereof) can be converted into RF signals 1314 and provided to corresponding RFIC chips 1312 for conditioning. Each amplifier 1320 of the RFIC chips 1312 amplifies the provided RF signals 1314, and each phase shifter 1324 can apply a phase shift to the G conditioned RF signals 1314 output. In Figure 13 In some examples of the subarray 1300, the phase shifter 1324 can apply a variable amount of phase adjustment in response to the beam weights 1326 provided from the controller 1328. Additionally or alternatively, the amplifier 1320 can provide a variable amount of amplitude adjustment in response to the beam weights 1326 provided from the controller 1328. The G RF signals 1314 can be provided to the RX subarray BFN circuit 1316. The RX subarray BFN circuit 1316 can combine the G RF signals 1314 to form a received subarray signal 1302, which can be provided to a beamformer for further processing.

[0120] Figure 14 A block diagram of a subarray 1400 for a phased array antenna is shown, depicting one of the J subarrays 108 operating in transmit mode and / or Figure 1 the logical interconnection of the subarray 200 of Figure 2 The subarray 1400 can be dynamically assigned to a specific beam among multiple beams. Additionally, the subarray 1400 can be employed to transmit an RF signal 1402 into free space in response to receiving the subarray signal 1403 from a beamformer. The beamformer can utilize Figure 1 the beamformer 112 of Figure 3 the beamformer 302 of Figure 4 the beamformer 402 of

[0121] The subarray beamforming circuit 1408 can include G RFIC chips 1412 and a transmit (TX) subarray BFN circuit. Each of the G RFIC chips 1412 can be coupled to a corresponding radiation element 1404. Each of the RFIC chips 1412 in the RFIC chips 1412 conditions the RF signal 1402 received from the TX subarray BFN circuit 1416 and provides the conditioned RF signal 1402 to the corresponding radiation element 1404. The TX subarray BFN circuit 1416 can be employed to implement Figure 2 the subarray BFN 212 of

[0122] In the illustrated example, each RFIC chip 1312 may include an amplifier 1420 and a phase shifter 1424. G RFIC chips 1412 may receive beam weights 1414 from a controller 1428, and the controller may be implemented using Figure 1 controller 120. The beam weights 1414 may be calculated by the controller 1428 based on a particular beam to which the subarray 1400 is assigned. In some examples, the beam weights 1414 may control the gain of each amplifier 1420 and / or the phase shift imposed by each phase shifter 1424. Thus, in some examples, each amplifier 1420 may be implemented as a variable gain amplifier, a switched attenuator circuit, etc.

[0123] In operation, a transmit beam signal 1403 may be provided from a beamformer to the TX subarray BFN circuit 1416. The TX subarray BFN circuit 1416 may divide the transmit beam signal 1403 into G RF signals 1402, which may be provided to G RFIC chips 1412. Each of the G RFIC chips 1412 may adjust the corresponding RF signal 1402 to generate an adjusted RF signal 1402, which may be provided to the corresponding radiating element 1404. In Figure 13 some examples of the subarray 1400, the phase shifter 1424 may impose a variable amount of phase adjustment in response to the beam weights 1414 provided from the controller 1428. Additionally or alternatively, the amplifier 1420 may provide a variable amount of amplitude adjustment in response to the beam weights 1414 provided from the controller 1428. Each radiating element 1404 propagates the corresponding adjusted RF signal 1402 into free space.

[0124] Figure 15 A block diagram of a subarray 1500 for a phased array antenna is shown, depicting the logical interconnection of one of the J subarrays 108 operating in a half-duplex mode and / or the subarray 200. The subarray 1500 may be dynamically assigned to a particular beam among multiple beams. The beamformer may be implemented using Figure 1 beamformer 112, Figure 1 beamformer 302, or Figure 3 beamformer 402 of Figure 4 the architecture. In the illustrated example, G radiating elements 1504 communicate with the subarray beamforming circuit 1508. In the half-duplex mode, the subarray 1500 switches between a receive mode and a transmit mode.

[0125] The subarray beamforming circuit 1508 may include G RFIC chips 1512 and a subarray BFN circuit 1514. Each of the G RFIC chips 1512 may be coupled to a corresponding radiating element 1504. In the illustrated example, each RFIC chip 1512 may include a receive path 1516 and a transmit path 1520. The receive path 1516 may include a receive amplifier 1524 and a receive phase shifter 1528 for conditioning a signal received from the corresponding radiating element 1504. Similarly, the transmit path 1520 may include a transmit amplifier 1532 and a transmit phase shifter 1536 for conditioning a corresponding RF signal 1522 provided from the subarray BFN circuit 1514.

[0126] The sub-array BFN circuit 1514 may include a port 1538 coupled to a beamformer. Port 1538 of the sub-array BFN circuit 1514 may be employed to receive a transmit sub-array signal 1515 from the beamformer or to provide a received sub-array signal 1516 to the beamformer.

[0127] Each RFIC chip 1512 may also include a pair of switching devices 1540 (eg, transistor switching devices) for switching between a receive mode and a transmit mode. The RFIC chip 1512 may receive beam weights 1542 from a controller 1544 and may utilize Figure 1 The controller 120 of the embodiment of the present invention can be implemented as a controller. The beam weights 1542 can control the state of a pair of switching devices 1540 to switch the subarray 1500 from a receive mode to a transmit mode, or vice versa. In addition, in some examples, the beam weights 1542 provided from the controller 1544 can control the amplitude adjustment of the variable amount applied by each receive amplifier 1524 and each transmit amplifier 1532. Therefore, in some examples, each receive amplifier 1524 and each transmit amplifier 1532 can be implemented as a variable gain amplifier, a switching attenuator circuit, etc. Similarly, in some examples, the beam weights 1542 provided from the controller 1544 can control the phase adjustment of the variable amount applied by each receive phase shifter 1528 and each transmit phase shifter 1536.

[0128] In the operation in the receive mode, the controller 1544 sets a pair of switching devices 1540 of the RFIC chip 1512 to route signals through the receive path 1516. Further, in the receive mode, the RF signals 1522 received by each of the G radiating elements 1504 (or a certain subgroup thereof) can be provided to the corresponding RFIC chip 1512 for conditioning. Each receive amplifier 1524 of the RFIC chip 1512 amplifies the provided signal, and each receive phase shifter 1528 applies a phase shift to the output G RF signals 1522. The G RF signals 1522 can be provided to the subarray BFN circuit 1514. The subarray BFN circuit 1514 can combine the G RF signals 1522 to form a received subarray signal 1516, and the received subarray signal can be provided to a beamformer for processing.

[0129] In the operation in the transmit mode, the controller 1544 sets a pair of switching devices 1540 to switch to the transmit path 1520 to transmit a transmit subarray signal 1515 that can be provided to the subarray BFN circuit 1514 from a beamformer. The subarray BFN circuit 1514 can divide the transmit subarray signal 1515 into G RF signals 1522, and the G RF signals can be provided to the G RFIC chips 1512. Each of the G RFIC chips 1512 can condition the corresponding RF signal 1522 based on the beam weights 1542 to generate a conditioned RF signal 1522, and the conditioned RF signal can be provided to the corresponding radiating element 1504. In the illustrated example, the conditioning can include, based on the beam weights 1542, the transmit phase shifter 1536 applying a phase shift to the RF signal 1522 and the transmit amplifier 1532 amplifying the RF signal 1522. Each radiating element 1504 propagates the corresponding conditioned RF signal 1522 into free space.

[0130] In the half-duplex mode, the subarray 1500 switches between the receive mode and the transmit mode. In this way, the same G radiating elements 1504 can be used for both the transmission and reception of the RF signals 1522.

[0131] Figure 16 A block diagram of a subarray 1600 for a phased array antenna is shown, which depicts one of the J subarrays 108 operating in the frequency-division duplex mode and / or the logical interconnection of the subarray 200. The subarray 1600 can be dynamically assigned to a specific beam among multiple beams. The subarray 1600 can communicate with a beamformer, and the beamformer can utilize Figure 1 the beamformer 112 of Figure 1 the beamformer 302 of Figure 3 or the beamformer 302 of Figure 4It is implemented by the architecture of the beamformer 402. In the illustrated example, G radiating elements 1604 communicate with the subarray beamforming circuit 1508. In the frequency division duplex mode, the subarray 1600 may include circuitry for processing the RF signals 1602 received within the receive band and for propagating the RF signals 1602 within the transmit band.

[0132] The subarray beamforming circuit 1608 may include G RFIC chips 1612 and a subarray BFN circuit 1614. Each of the G RFIC chips 1612 may be coupled to a corresponding radiating element 1604. In the illustrated example, each RFIC chip 1612 may include a receive beamforming circuit along the receive path 1616 and a transmit beamforming circuit along the transmit path 1620. The receive beamforming circuit may include a receive amplifier 1624 and a receive phase shifter 1628 for conditioning the signals received from the corresponding radiating element 1604. Similarly, the transmit beamforming circuit may include a transmit amplifier 1632 and a transmit phase shifter 1636 for conditioning the corresponding RF signals 1602 provided from the subarray BFN circuit 1614.

[0133] The subarray BFN circuit 1614 may include a first port 1638 and a second port 1639 each coupled to the beamformer. The first port 1638 of the subarray BFN circuit 1614 may be employed to receive the transmit subarray signal 1615 from the beamformer. The second port 1648 may be employed to provide the received subarray signal 1616 to the beamformer.

[0134] Additionally, the receive path 1616 may include an input receive filter 1640 and an output receive filter 1644. The input receive filter 1640 and the output receive filter 1644 may be implemented as relatively narrow bandpass filters for removing signals having frequencies outside the receive band. Thus, the input receive filter 1640 and the output receive filter 1644 may have a passband set to the receive band. Similarly, the transmit path 1620 may include an input transmit filter 1648 and an output transmit filter 1652. The input transmit filter 1648 and the output transmit filter 1652 may be implemented as relatively narrow bandpass filters for removing signals having frequencies outside the transmit band. Thus, the input transmit filter 1648 and the output transmit filter 1652 may have a passband set to the transmit band. In other examples, the output receive filter 1644 and the output transmit filter 1652 may be replaced with another component (such as an RF circulator).

[0135] The RFIC chip 1612 may receive beam weights 1658 from a controller 1660 and may utilize Figure 1The controller 120 is implemented to achieve the controller. The beam weights 1658 can be calculated by the controller based on the specific beam to which the sub-array 1600 is assigned. In some examples, the beam weights 1658 control the passband and / or bandwidth of the input transmit filter 1640 and the output transmit filter 1644. Similarly, in some examples, the beam weights 1658 provided from the controller 1660 control the passband and / or bandwidth of the input transmit filter 1648 and the output transmit filter 1652. Additionally or alternatively, the beam weights 1658 provided from the controller 1660 can control the variable amount of amplitude adjustment applied by each receive amplifier 1624 and each transmit amplifier 1632. Thus, in some examples, each receive amplifier 1624 and each transmit amplifier 1632 can be implemented as a variable gain amplifier, a switched attenuator circuit, etc. Similarly, in some examples, the beam weights 1658 provided from the controller 1660 can control the variable amount of phase adjustment applied by each receive phase shifter 1628 and each transmit phase shifter 1636.

[0136] In operation, the sub-array 1600 can operate in both the receive mode and the transmit mode based on the frequency of the signal traversing the sub-array 1600. More specifically, the RF signals 1602 can be received by each of the G radiating elements 1604 (or some subgroup thereof), and these RF signals 1602 can be provided to the corresponding RFIC chip 1612 for conditioning. The signals within the passband (receive band) of the input receive filter 1640 can be conditioned (e.g., amplified and phase-shifted) by the receive path 1616 of the corresponding RFIC chip 1612. The conditioned RF signals 1602 can be filtered by the output receive filter 1644 and provided as the RF signals 1602 to the sub-array BFN circuit 1614. In this way, the sub-array BFN circuit 1614 receives G RF signals 1602 from the G RFIC chips 1612, where each of the received G RF signals 1602 is within the receive band. The sub-array BFN circuit 1614 can combine the received G RF signals 1602 to form the received sub-array signal 1616, which can be provided to the beamformer for further processing through the second port 1639.

[0137] Additionally, while receiving the RF signal, the transmit subarray signal 1615 can be provided from the beamformer to the subarray BFN circuit 1614 at the second port 1638. The subarray BFN circuit 1614 can divide the transmit subarray signal 1615 into G RF signals 1602, and the G RF signals can be provided to G RFIC chips 1612. The input transmit filter 1648 of each RFIC chip in the G RFIC chips 1612 removes signals outside the passband (transmit band). Additionally, the transmit path 1620 can adjust (phase shift and amplify) the corresponding RF signal 1602 to generate an adjusted RF signal 1602, and the adjusted RF signal can be provided to the corresponding radiating element 1604 through the output transmit filter 1652. Each radiating element 1604 propagates the corresponding adjusted RF into free space.

[0138] In the subarray 1600, the frequency control of the traversing signal is through the signal routing performed by the subarray 1600. In this way, the same radiating element 1604 can be used for both the transmission and reception of the RF signal 1602. In other examples, different radiating elements 1604 can be utilized for transmission and reception, such that the subarray includes a first set of radiating elements 1604 for transmission and a second (different) set of radiating elements for reception. The two sets of radiating elements can be, for example, superimposed within each subarray 1600 such that the radiating elements 1604 for transmission are located in a first region that at least partially overlaps with a second region containing the radiating elements 1604 for reception. Additionally, in some examples, the subarray 1600 can have an architecture that intermittently switches between a transmit mode and a receive mode to provide half-duplex.

[0139] Figure 17 A block diagram of a subarray 1700 for a phased array antenna is shown, depicting the operation in a polarization duplex mode (which can be a specific configuration of a half-duplex mode) Figure 1 of one of the J subarrays 108 and / or the logical interconnection of the subarray 200. The subarray 1700 can be dynamically assigned to a specific beam among multiple beams. The subarray 1700 can communicate with a beamformer, and the beamformer can utilize Figure 1 the beamformer 112 of Figure 3 the beamformer 302 or Figure 4 the architecture of the beamformer 402 of

[0140] The subarray beamforming circuit 1708 may include G RFIC chips 1712 and a subarray BFN circuit 1714. Each of the G RFIC chips 1712 may be coupled to a corresponding radiating element 1704. In the illustrated example, each RFIC chip 1712 may include a receive path 1716 and a transmit path 1720. The receive path 1716 may include a receive amplifier 1724 and a receive phase shifter 1732 for conditioning an RF signal 1710 received from the corresponding radiating element 1704. Similarly, the transmit path 1720 may include a transmit amplifier 1734 and a transmit phase shifter 1738 for conditioning a corresponding RF signal 1710 provided from the subarray BFN circuit 1714.

[0141] The subarray BFN circuit 1714 may include a port 1715 coupled to a beamformer. The port 1715 of the subarray BFN circuit 1714 may be employed to receive a transmit subarray signal 1737 from the beamformer or transmit a received subarray signal 1739 to the beamformer.

[0142] The receive path 1716 may be coupled to a first port 1740 of the radiating element 1704, and the transmit path 1720 may be coupled to a second port 1744 of the radiating element 1704. The first port 1740 of the radiating element 1704 may be configured to output an RF signal 1710 received at the radiating element 1704 that is in a first polarization, and the second port 1744 of the radiating element 1704 may be configured to transmit a signal received at the radiating element 1704 that has a second polarization orthogonal to the first polarization. For example, the first polarization may be vertical polarization and the second polarization may be horizontal polarization, or vice versa. Alternatively, the first polarization may be right-hand circular polarization (RHCP) and the second polarization may be left-hand circular polarization (LHCP), or vice versa.

[0143] Each RFIC chip 1712 may further include switching means 1748 (e.g., a transistor switching means) for switching between a receive mode and a transmit mode. The RFIC chip 1712 may receive beam weights 1713 from a controller 1760 and may utilize Figure 1The controller 120 is implemented to achieve this controller. The beam weights 1713 can be calculated by the controller 1760 based on the beam to which the subarray 1700 is assigned. The beam weights 1713 can control the state of the switching device 1748 to switch the subarray 1700 from the receive mode to the transmit mode, or vice versa. Additionally, in some examples, the beam weights 1713 provided from the controller 1760 can control the variable amplitude adjustment applied by each receive amplifier 1724 and each transmit amplifier 1734. Thus, in some examples, each receive amplifier 1724 and each transmit amplifier 1734 can be implemented as a variable gain amplifier, a switched attenuator circuit, etc. Similarly, in some examples, the beam weights 1713 provided from the controller 1760 can control the variable phase adjustment applied by each receive phase shifter 1732 and each transmit phase shifter 1738.

[0144] In the operation in the receive mode, the controller 1760 sets the switching device 1748 of the RFIC chip 1712 to route the signal through the receive path 1716. Additionally, in the receive mode, the RF signals 1710 in the first polarization duplex mode received by each of the G radiating elements 1704 (or a certain subgroup thereof) can be provided to the corresponding RFIC chip 1712 for adjustment. Each receive amplifier 1724 of the RFIC chip 1712 can amplify the provided signal, and each receive phase shifter 1732 can apply a phase shift to the output G RF signals 1710. The G RF signals 1710 can be provided to the subarray BFN circuit 1714. The subarray BFN circuit 1714 can combine the G RF signals 1710 to form a received subarray, which can be provided to the beamformer for processing.

[0145] In the operation in the transmit mode, the controller 1760 sets the switching device 1748 to switch to the transmit path 1720 to transmit the transmit beam signal 1737 that can be provided from the local system to the subarray BFN circuit 1714. The subarray BFN circuit 1714 can divide the transmit beam signal 1737 into G RF signals 1710, and the G RF signals can be provided to the G RFIC chips 1712. Each of the G RFIC chips 1712 can adjust the corresponding RF signal 1710 to provide the adjusted RF signal 1710 to the corresponding radiating element 1704. In the illustrated example, the adjustment can include, based on the beam weights 1713, the transmit phase shifter 1738 applying a phase shift to the RF signal 1710 and the transmit amplifier 1734 amplifying the RF signal 1710. Each radiating element 1704 propagates the corresponding adjusted RF signal 1710 into free space.

[0146] In the polarized duplex mode, the sub-array 1700 switches between the receive mode and the transmit mode. However, by utilizing the orthogonality relationship between the signals at the first port 1740 and the second port 1744 of the G radiating elements 1704, a single switching device 1748 can be utilized to enable each RFIC chip 1712 to reduce signal loss. Additionally, in this way, the same radiating elements 1704 can be employed for both the transmission and reception of the RF signal 1710.

[0147] What has been described above are examples. Of course, it is not possible to describe every conceivable combination of components or methods, but those of ordinary skill in the art will recognize that many additional combinations and permutations are possible. Accordingly, this disclosure is intended to cover all such changes, modifications, and variations that fall within the scope of this application (including the appended claims). As used herein, the term "comprising" means including but not limited to, and the term "including" means including but not limited to. The term "based on" means at least partially based on. Additionally, in the case where this disclosure or a claim recites "a," "an," "the first," or "another" element or its equivalent, it should be construed to include one or more than one such element, neither requiring nor precluding two or more such elements.

Claims

1. A multi-beam phased array antenna system (100), the multi-beam phased array antenna system comprising: A beam former (112) that couples a plurality of sub-array signals to a signal path of one of the plurality of beam signals in response to a control signal; A plurality of sub-arrays (108) that transmit a plurality of beams corresponding to the plurality of beam signals; And A controller (120); wherein each of the plurality of sub-arrays includes: A plurality of radiating elements (204); and A sub-array beam forming circuit (208) that can only contribute (i) one transmit beam and / or (ii) one receive beam, adjusts the RF signals (206) transmitted by the plurality of radiating elements (204) in response to corresponding beam weights (220), and converts between the adjusted RF signals (206) and one corresponding sub-array signal (218) of the plurality of sub-array signals (218) by combining and / or dividing the adjusted RF signals, wherein the corresponding sub-array signal (208) corresponds to one specific beam of the plurality of beams; Wherein the controller performs the following operations: Determine two or more of the plurality of beams, wherein the two or more beams are (a) two or more transmit beams or (b) two or more receive beams; Allocate non-overlapping sub-groups of the plurality of sub-arrays (108) to each of the determined two or more beams such that each of the plurality of sub-arrays (108) is only allocated to one specific beam of the plurality of beams; Provide the corresponding beam weights to each of the plurality of sub-arrays (108) based on the allocation; and Provide the control signal to the beam former (112) based on the allocation.

2. The multi-beam phased array antenna system (100) according to claim 1, wherein the sub-array beam forming circuit (208) of each of the plurality of sub-arrays further includes: A set of radio frequency integrated circuit RFIC chips (216) coupled to the plurality of radiating elements, and each RFIC chip (216) in the set of RFIC chips (216) applies a beam weight to the RF signal (206) in response to the beam weight (220) provided from the controller (120).

3. The multi-beam phased array antenna system (100) according to claim 1, wherein the sub-array beam forming circuit (208) of each of the plurality of sub-arrays includes an amplifier and a phase shifter that amplify and phase shift the RF signals transmitted by the plurality of radiating elements (204) in response to the beam weight (220) provided by the controller (120).

4. The multi-beam phased array antenna system (100) according to claim 1, wherein the sub-array beam forming circuit (208) of each of the plurality of sub-arrays further includes: Sub-array beamforming network BFN (212), the sub-array BFN including a signal path providing conversion between the corresponding sub-array signals (218) and the RF signal (206).

5. The multi-beam phased array antenna system (100) according to claim 1, wherein the controller (120) assigns a first subgroup of the disjoint sub-arrays (108) to a first determined beam of the determined two or more beams, and assigns a second subgroup of the disjoint sub-arrays (108) to a second determined beam of the two or more beams, wherein at least one of the direction, frequency, and polarization of the first determined beam is different from the direction, frequency, and polarization of the second determined beam.

6. The multi-beam phased array antenna system (100) according to claim 1, wherein the determined two or more beams include at least four determined beams, and the system further includes: A transmitting antenna, the transmitting antenna including a first subgroup of sub-arrays (108) and a second subgroup of sub-arrays in the subgroup of disjoint sub-arrays (108); And A receiving antenna, the receiving antenna including a third subgroup of sub-arrays and a fourth subgroup of sub-arrays in the subgroup of disjoint sub-arrays (108); Wherein the controller (120) assigns the first subgroup of sub-arrays (108) to transmit the first beam of the at least four determined beams, assigns the second subgroup of sub-arrays (108) to transmit the second beam of the at least four determined beams, assigns the third subgroup of sub-arrays (108) to receive the third beam of the at least four determined beams, and assigns the fourth subgroup of sub-arrays (108) to receive the fourth beam of the at least four determined beams.

7. The multi-beam phased array antenna system (100) according to claim 6, wherein the transmitting antenna and the receiving antenna are spaced apart.

8. The multi-beam phased array antenna system (100) according to claim 6, wherein the transmitting antenna at least partially overlaps with the receiving antenna.

9. The multi-beam phased array antenna system (100) according to any one of the preceding claims, wherein a first sub-array and a second sub-array among the plurality of sub-arrays (108) have a first shape.

10. The multi-beam phased array antenna system (100) according to claim 9, wherein a third sub-array among the plurality of sub-arrays (108) has a second shape different from the first shape.

11. The multi-beam phased array antenna system (100) according to claim 1, wherein the plurality of sub-arrays are arranged in a regular grid.

12. The multi-beam phased array antenna system (100) according to claim 1, wherein the plurality of sub-arrays are arranged in an irregular pattern.

13. The multi-beam phased array antenna system (100) according to claim 5, wherein the beamformer (312) further includes: A plurality of beamforming networks BFN (312), wherein each BFN of the plurality of BFNs (312) is associated with only one of the plurality of beams; and A plurality of switching devices (320), wherein each switching device (320) is coupled to a given sub - array (308) of the plurality of sub - arrays (308) and a given BFN (312) of the plurality of BFNs (312), and the state of each switching device of the plurality of switching devices (320) responds to the control signal from the controller (324).

14. The multi - beam phased array antenna system (100) according to claim 13, wherein the plurality of switching devices (320) couple each sub - array (308) in a first sub - group of the disjoint sub - arrays (308) to a first BFN (312) of the plurality of BFNs (312) associated with the first determined beam and couple each sub - array (308) in a second sub - group of the disjoint sub - arrays to a second BFN (312) of the plurality of BFNs (312) associated with the second determined beam in response to the control signal from the controller (324).

15. The multi - beam phased array antenna system (100) according to claim 14, wherein the first BFN (312) applies beam weights to the sub - array signals associated with the first sub - group of sub - arrays (308) in response to the control signal from the controller (324), and the second BFN (312) applies beam weights to the sub - array signals associated with the second sub - group of sub - arrays (308) in response to the control signal from the controller (324).

16. The multi - beam phased array antenna system (100) according to claim 1, wherein the beamformer further comprises: Digital logic components (412) that form each of the plurality of beams in response to the control signal from the controller (424), wherein the digital logic components (412) are coupled to each of the plurality of sub - arrays (408), and the digital logic components (412) associate a first sub - group of sub - array signals with a first beam of the determined two or more beams of the plurality of beams and associate a second sub - group of sub - array signals with a second beam of the determined two or more beams of the plurality of beams in response to the control signal from the controller (424).

17. The multi-beam phased array antenna system (100) according to claim 16, wherein the beamformer (402) further includes a set of analog-to-digital converters ADC (420) coupled between the digital logic component (412) and each of the plurality of sub-arrays (408), and each ADC (420) in the set of ADCs (420) transmits a corresponding sub-array signal with each of the plurality of sub-arrays (408).

18. The multi-beam phased array antenna system (100) according to claim 1, the multi-beam phased array antenna system further comprising: A set of modems (116), wherein each modem (116) in the set of modems (116) is coupled to the beamformer (112), and each modem (116) transmits data encoded on a corresponding one of the plurality of beam signals with the beamformer (112).

19. The multi-beam phased array antenna system (100) according to claim 1, wherein each of the plurality of sub-arrays (408) has a top surface with a regular tile shape.

20. The multi-beam phased array antenna system (100) according to claim 1, wherein each corresponding sub-array signal in the plurality of sub-array signals corresponds to only one specific beam in the plurality of beams.

21. The multi-beam phased array antenna system (100) according to claim 1, wherein the sub-array beamforming circuit (208) of each of the plurality of sub-arrays converts between a corresponding adjusted RF signal and only one corresponding sub-array signal (218) of a first communication type in response to the beam weights (220) provided by the controller (120), wherein, The first communication type is transmission or reception.

22. The multi-beam phased array antenna system (100) according to claim 21, wherein the sub-array beamforming circuit (208) of each of the plurality of sub-arrays (108) includes a sub-array signal port (214) for transmitting the corresponding one of the plurality of sub-array signals (218).

23. The multi-beam phased array antenna system (100) according to claim 22, wherein the sub-array beamforming circuit (208) of each sub-array has only one sub-array signal port (214).

24. The multi-beam phased array antenna system (100) according to claim 22, wherein the sub-array beamforming circuit (208) of each sub-array (108) among the plurality of sub-arrays (108) further converts between the corresponding adjusted RF signal and only one corresponding sub-array signal (218) of a second communication type, and includes a second sub-array signal port (214) for transmitting the one corresponding sub-array signal (218) of the second communication type, wherein, The second communication type is reception or transmission and is different from the first communication type.

25. The multi-beam phased array antenna system (100) according to claim 1, the beamformer (502) further includes a plurality of interconnected beam conversion circuits (512), wherein each beam conversion circuit (512) is coupled to a corresponding sub-array (508) among the plurality of sub-arrays (508).

26. The multi-beam phased array antenna system (100) according to claim 1, wherein the two or more beams are transmit beams.

27. The multi-beam phased array antenna system (100) according to the foregoing claim 1, wherein the two or more beams are receive beams.

28. The multi-beam phased array antenna system (100) according to claim 1, wherein the sub-array beamforming circuit of each of the plurality of sub-arrays is a receive sub-array beamforming circuit, and each of the plurality of sub-arrays further includes: A transmit subarray beamforming circuit (208) that adjusts RF signals (206) transmitted by the plurality of radiating elements (204) in response to corresponding beam weights (220) and converts a corresponding subarray signal (218) of the plurality of subarray signals (218) into the adjusted RF signal (206), wherein the corresponding subarray signal (208) corresponds to a specific transmit beam of the plurality of beams; wherein the controller further performs the following operations: determine two or more transmit beams among the plurality of beams; and assign disjoint subarray (108) subgroups of the plurality of subarrays (108) to each of the determined two or more transmit beams.

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