A reconfigurable feed

Abstract

The present invention discloses a reconfigurable feed source, comprising: four dual-polarized antennas, each outputting two polarized signals; eight low-noise amplifiers, each connected to the polarized signals of the dual-polarized antennas; eight power splitters, each connected to the output of the low-noise amplifiers; sixteen attenuators, each connected to the output of the power splitters; sixteen phase shifters, each connected to the output of the attenuators; eight combiners, each receiving two processed signals from the corresponding dual-polarized antennas and outputting a synthesized signal; a first synthesizing network, configured to receive and synthesize the signals output by the combiner, and output a synthesized signal; and a second synthesizing network, configured to receive and synthesize the signals output by the combiner, and output a synthesized signal. The present invention amplifies, power splits, attenuates, phase-shifts, and synthesizes the dual-polarized antenna signals to obtain two signals. Each signal can independently achieve amplitude weighting and phase-shift synthesis of each antenna signal, thereby achieving feed pattern reconstruction and polarization reconstruction.

Description

Technical Field

[0001] The present invention relates to the technical field of reflector antenna feed sources, and in particular to a reconfigurable feed source. Background Art

[0002] The feed is a core component of measurement and control, communication, and radar antenna feed systems. Reconfigurable feeds can be divided into frequency reconfigurable feeds, pattern reconfigurable feeds, polarization reconfigurable feeds, and hybrid reconfigurable feeds according to the controlled parameters. Feed reconstruction is mainly achieved through the following technical approaches: the first is to use various microwave electronic devices to change the feed structure of the feed antenna to achieve pattern or polarization reconstruction; the second is to use RF switching devices to change the feed structure of the feed network to achieve polarization switching; the third is to use phase shifters, polarization rotators, etc. to adjust the signal phase to achieve polarization adjustment or tracking. Current feed reconfiguration technology has poor flexibility and can only adjust a single parameter. In addition, the reconstruction principle is complex and the structure is cumbersome, making it difficult to adapt to various application scenarios.

[0003] Systems such as measurement and control, communications, and radar antenna feeds require feeds that can adapt to multiple polarization modes while minimizing polarization mismatch losses. They also require flexible reconfiguration of the radiation pattern to accommodate various tracking modes, including single-pulse tracking, single-axis tracking, and conical scanning tracking. Therefore, developing a feed that can flexibly reconfigure the radiation pattern and polarization has broad application value. With the advancement of microelectronics technology, components such as the low-noise amplifier, power splitter, attenuator, phase shifter, combiner, and combining network can be integrated into a single or multiple chips, further reducing system design complexity and application costs, making them economically viable.

[0004] To solve the above problems, the present invention designs a reconfigurable feed source based on the phase control principle. The feed source amplifies, power divides, attenuates, phase-shifts and synthesizes the dual-polarized antenna signals to obtain two signals. Each signal can independently realize the amplitude weighting and phase-shift synthesis of each antenna signal, thereby realizing the feed source's directional pattern reconstruction and polarization reconstruction. Summary of the Invention

[0005] In view of the above problems, the present invention provides a reconfigurable feed source, comprising:

[0006] Four dual-polarized antennas (E1, E2, E3, and E4) for receiving free-space signals, wherein each dual-polarized antenna outputs two polarized signals (E_1A and E_1B, E_2A and E_2B, E_3A and E_3B, and E_4A and E_4B);

[0007] Eight low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, and LAN_4B), respectively connected to the polarized signals of the dual-polarized antennas and configured to amplify the received polarized signals;

[0008] Eight power dividers (DIV_1A, DIV_1B, DIV_2A, DIV_2B, DIV_3A, DIV_3B, DIV_4A, DIV_4B), respectively connected to the output end of the low noise amplifier, for dividing the amplified signal into two paths;

[0009] Sixteen attenuators (AT_1AX, AT_1AY, AT_1BX, AT_1BY, AT_2AX, AT_2AY, AT_2BX, AT_2BY, AT_3AX, AT_3AY, AT_3BX, AT_3BY, AT_4AX, AT_4AY, AT_4BX, AT_4BY), respectively connected to the output end of the power divider, for adjusting the amplitude of the signal;

[0010] Sixteen phase shifters (PH_1AX, PH_1AY, PH_1BX, PH_1BY, PH_2AX, PH_2AY, PH_2BX, PH_2BY, PH_3AX, PH_3AY, PH_3BX, PH_3BY, PH_4AX, PH_4AY, PH_4BX, PH_4BY), respectively connected to the output end of the attenuator, for adjusting the phase of the signal;

[0011] Eight combiners (ADD_1X, ADD_1Y, ADD_2X, ADD_2Y, ADD_3X, ADD_3Y, ADD_4X, ADD_4Y). Each combiner receives two processed signals of different polarizations from the corresponding dual-polarization antenna and outputs a combined signal (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y).

[0012] a first combining network (ADD_X), configured to receive and combine the signals (S_1X, S_2X, S_3X, S_4X) output by the combiner, and output a combined signal (RX);

[0013] The second combining network (ADD_Y) is used to receive and combine the signals (S_1Y, S_2Y, S_3Y, S_4Y) output by the combiner, and output a combined signal (RY).

[0014] In an optional manner, the combiner ADD_1X combines the outputs of the phase shifters PH_1AX and PH_1BX;

[0015] The combiner ADD_1Y combines the outputs of the phase shifters PH_1AY and PH_1BY;

[0016] The combiner ADD_2X combines the outputs of the phase shifters PH_2AX and PH_2BX;

[0017] The combiner ADD_2Y combines the outputs of the phase shifters PH_2AY and PH_2BY;

[0018] The combiner ADD_3X combines the outputs of the phase shifters PH_3AX and PH_3BX;

[0019] The combiner ADD_3Y combines the outputs of the phase shifters PH_3AY and PH_3BY;

[0020] The combiner ADD_4X combines the outputs of the phase shifters PH_4AX and PH_4BX;

[0021] The combiner ADD_4Y combines the outputs of the phase shifters PH_4AY and PH_4BY.

[0022] In an optional manner, the feed source establishes a coordinate plane XOY with its normal direction as a reference, and the four dual-polarized antennas (E1, E2, E3 and E4) of the feed source are arranged in four quadrants of the plane XOY;

[0023] The dual-polarized antennas (E1, E2, E3, E4) are all receiving antennas and are used in conjunction with the transmitting antenna.

[0024] In an optional embodiment, the low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, LAN_4B) are respectively connected to the polarization signals (E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, E_4B) of the corresponding dual-polarization antennas for amplifying the received polarization signals.

[0025] In an optional manner, the positions of the attenuator and the phase shifter in the signal transmission path can be interchanged, and the attenuator can be placed after the phase shifter.

[0026] In an optional manner, the low noise amplifier is implemented by one or more stages of low noise amplifiers;

[0027] The phase shifter is realized by a single-stage or multi-stage phase shifter;

[0028] The attenuator is implemented by a single-stage or multi-stage attenuator.

[0029] In an optional embodiment, the signals (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y) are composed of any two of the different polarization signals (E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, E_4B) by adjusting the values of the attenuator and the phase shifter to achieve polarization adjustability.

[0030] In an optional manner, the low noise amplifier, power splitter, attenuator, phase shifter, combiner and synthesis network are implemented using discrete devices or integrated devices.

[0031] In an optional manner, the feed is reconstructed by configuring the values of each attenuator and phase shifter, including an arbitrary polarization feed, a single pulse feed, and a conical scanning feed;

[0032] The reconstructing of the feed beam further includes:

[0033] Calculate the required adjustments for the attenuators (AT_1AX to AT_4BY) and phase shifters (PH_1AX to PH_4BY) for each dual-polarized antenna based on the target beam shape and polarization requirements.

[0034] adjusting the settings of each attenuator and phase shifter according to the adjustment value to change the amplitude and phase on each signal path;

[0035] Until the required beam shape and polarization state are achieved, dynamic reconstruction of the feed is achieved.

[0036] In an optional manner, the arbitrary polarization feed includes linear polarization, circular polarization and elliptical polarization, and the polarization direction is adjustable.

[0037] According to the solution provided by the present invention, it includes: four dual-polarized antennas (E1, E2, E3, E4) for receiving free-space signals, wherein each dual-polarized antenna outputs two polarized signals (E_1A and E_1B, E_2A and E_2B, E_3A and E_3B, E_4A and E_4B); eight low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, LAN_4B), respectively connected to the polarized signals of the dual-polarized antennas, for amplifying the received polarized signals; eight power dividers (DIV _1A, DIV_1B, DIV_2A, DIV_2B, DIV_3A, DIV_3B, DIV_4A, DIV_4B), respectively connected to the output end of the low noise amplifier, for dividing the amplified signal into two paths; sixteen attenuators (AT_1AX, AT_1AY, AT_1BX, AT_1BY, AT_2AX, AT_2AY, AT_2BX, AT_2BY, AT_3AX, AT_3AY, AT_3BX, AT_3BY, AT_4AX, AT_4AY, AT_4BX, AT_4BY), respectively connected to the power divider The output end of the attenuator is connected to adjust the amplitude of the signal; sixteen phase shifters (PH_1AX, PH_1AY, PH_1BX, PH_1BY, PH_2AX, PH_2AY, PH_2BX, PH_2BY, PH_3AX, PH_3AY, PH_3BX, PH_3BY, PH_4AX, PH_4AY, PH_4BX, PH_4BY) are respectively connected to the output end of the attenuator to adjust the phase of the signal; eight combiners (ADD_1X, ADD_1Y, ADD_2X, ADD_2Y, ADD_3X, ADD_3Y, ADD_ 4X, ADD_4Y), each combiner receives two processed signals from the corresponding dual-polarized antenna and outputs a synthesized signal (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y); a first synthesizing network (ADD_X) is used to receive and synthesize the signals (S_1X, S_2X, S_3X, S_4X) output by the combiner and output a synthesized signal (RX); a second synthesizing network (ADD_Y) is used to receive and synthesize the signals (S_1Y, S_2Y, S_3Y, S_4Y) output by the combiner and output a synthesized signal (RY). The present invention amplifies, power divides, attenuates, phase-shifts, and synthesizes the dual-polarized antenna signals to obtain two signals. Each signal can independently achieve amplitude weighting and phase-shift synthesis of each antenna signal, thereby realizing feed pattern reconstruction and polarization reconstruction.

[0038] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0040] Figure 1 A schematic diagram of the feed antenna layout according to an embodiment of the present invention is shown;

[0041] Figure 2 A principle block diagram of a reconfigurable feed according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0042] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0043] Figure 1 FIG. 1 shows a schematic diagram of a feed antenna layout according to an embodiment of the present invention. Figure 2 FIG1 shows a block diagram of the principle of a reconfigurable feed source according to an embodiment of the present invention. Figure 1 、 Figure 2 As shown, including:

[0044] Four dual-polarized antennas (E1, E2, E3, and E4) for receiving free-space signals, wherein each dual-polarized antenna outputs two polarized signals (E_1A and E_1B, E_2A and E_2B, E_3A and E_3B, and E_4A and E_4B);

[0045] Eight low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, and LAN_4B), respectively connected to the polarized signals of the dual-polarized antennas and configured to amplify the received polarized signals;

[0046] Eight power dividers (DIV_1A, DIV_1B, DIV_2A, DIV_2B, DIV_3A, DIV_3B, DIV_4A, DIV_4B), respectively connected to the output end of the low noise amplifier, for dividing the amplified signal into two paths;

[0047] Sixteen attenuators (AT_1AX, AT_1AY, AT_1BX, AT_1BY, AT_2AX, AT_2AY, AT_2BX, AT_2BY, AT_3AX, AT_3AY, AT_3BX, AT_3BY, AT_4AX, AT_4AY, AT_4BX, AT_4BY), respectively connected to the output end of the power divider, for adjusting the amplitude of the signal;

[0048] Sixteen phase shifters (PH_1AX, PH_1AY, PH_1BX, PH_1BY, PH_2AX, PH_2AY, PH_2BX, PH_2BY, PH_3AX, PH_3AY, PH_3BX, PH_3BY, PH_4AX, PH_4AY, PH_4BX, PH_4BY), respectively connected to the output end of the attenuator, for adjusting the phase of the signal;

[0049] Eight combiners (ADD_1X, ADD_1Y, ADD_2X, ADD_2Y, ADD_3X, ADD_3Y, ADD_4X, ADD_4Y), each of which receives two processed signals from the corresponding dual-polarized antenna and outputs a combined signal (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y);

[0050] a first combining network (ADD_X), configured to receive and combine the signals (S_1X, S_2X, S_3X, S_4X) output by the combiner, and output a combined signal (RX);

[0051] The second combining network (ADD_Y) is used to receive and combine the signals (S_1Y, S_2Y, S_3Y, S_4Y) output by the combiner, and output a combined signal (RY).

[0052] In this embodiment, the polarization state of the final synthesized signal can be flexibly adjusted by independently controlling the attenuator and phase shifter of each signal path. For example, circular polarization generates a horizontally polarized or vertically polarized beam, and linear polarization generates a left-hand circularly polarized or right-hand circularly polarized beam. The polarization direction can be dynamically changed to follow the polarization change of the target signal. The beam is scanned in space by changing the value of the attenuator, and a beam of a specific shape (such as a narrow beam or a wide beam) is achieved by controlling the attenuator and the phase shifter. Since both polarization and beam are reconfigurable, the feed can perform a variety of tasks, such as radar (to achieve polarization resolution and beam scanning), communication (to achieve optimal polarization matching and improve communication quality), remote sensing (to achieve remote sensing data in different polarization states and obtain more information), etc.

[0053] Specifically, dual-polarized antennas (E1 to E4) can be patch antennas, horn antennas, cross-dipole antennas, and other dual-polarized antennas. Four dual-polarized antennas are evenly distributed in the four quadrants of the XOY plane, with the center as the coordinate origin, to ensure coverage of the required angular range. The two polarization directions of each dual-polarized antenna are typically orthogonal, for example, horizontal polarization and vertical polarization.

[0054] The low-noise amplifiers (LAN_1A to LAN_4B) use discrete low-noise amplifier chips or integrated amplifier modules to amplify weak received signals. The appropriate gain is selected based on the system link budget. By selecting an amplifier with a low noise figure, the system signal-to-noise ratio is improved.

[0055] The power divider (DIV_1A to DIV_4B) can be a resistive power divider, a microstrip power divider, or a Wilkinson power divider to evenly divide the input signal into two paths, ensuring that the phase and amplitude of each signal are basically consistent.

[0056] The attenuators (AT_1AX to AT_4BY) select digital attenuators, variable attenuators, or step attenuators to adjust the signal amplitude for weight control.

[0057] The phase shifters (PH_1AX to PH_4BY) select digital phase shifters, analog phase shifters, or ferrite phase shifters to adjust the signal phase and achieve signal phase shifting.

[0058] The combiner (ADD_1X to ADD_4Y) uses a Wilkinson combiner, a microstrip combiner, or a hybrid coupler to vector-synthesize two signals (after attenuation and phase shifting) from the same dual-polarization antenna to form a single-polarization signal.

[0059] The synthesis network (ADD_X and ADD_Y) uses a tree-like combining network or a series-parallel combination network to vector-synthesize the signals from different antenna units to form the final output signals RX and RY.

[0060] In this embodiment, a polarization-scanning radar is used as the radar's receiving antenna. The dual-polarization antennas (E1 to E4) output vertically and horizontally polarized signals. The attenuators and phase shifters are calibrated to ensure that the signals reaching the combiner (ADD_1X to ADD_4Y) are of equal amplitude and phase.

[0061] To detect the target's polarization characteristics, the phase shifter and attenuator values are adjusted in time, so that the received signal alternates between the following polarization states:

[0062] Vertical polarization: Only the vertical polarization channels (E_1A, E_2A, E_3A, E_4A) of each antenna are activated, and the rest of the channels are disabled.

[0063] Horizontal polarization: Only the horizontal polarization channels (E_1B, E_2B, E_3B, E_4B) of each antenna are activated, and the rest of the channels are disabled.

[0064] Left-hand circular polarization: The vertical polarization and horizontal polarization channels of the antenna are synthesized, and the phase shifter is adjusted to make the vertical polarization channel have a 90-degree phase difference with the horizontal polarization channel.

[0065] Right-hand circular polarization: The vertical polarization and horizontal polarization channels of the antenna are synthesized, and the phase shifter is adjusted so that there is a -90-degree phase difference between the vertical polarization channel and the horizontal polarization channel.

[0066] Polarization scanning: Adjust the value of the phase shifter to synthesize the tilted polarization signal, thereby tracking the polarization direction of the target signal.

[0067] The received data of different polarization states and different scanning directions are processed to obtain the polarization characteristics and position information of the target.

[0068] Set the attenuation values of attenuators AT_1AY, AT_1BY, AT_2AY, AT_2BY, AT_3AY, AT_3BY, AT_4AY, and AT_4BY to maximum or turn off the power supply to completely shut down the corresponding signal paths. Calibrate the attenuation values of attenuators AT_1AX, AT_1BX, AT_2AX, AT_2BX, AT_3AX, AT_3BX, AT_4AX, and AT_4BX to ensure the same amplitude at each attenuator. Adjust the phase shift values of phase shifters PH_1AX, PH_2AX, PH_3AX, and PH_4AX to 0 degrees and PH_1BY, PH_2BY, PH_3BY, and PH_4BY to 90 degrees to obtain a left-hand circularly polarized signal. Adjust the phase shifters PH_1AY, PH_2AY, PH_3AY, and PH_4AY to 90 degrees, and adjust the phase shifters PH_1BY, PH_2BY, PH_3BY, and PH_4BY to 0 degrees to obtain a right-hand circularly polarized signal. Adjust the phase shifters PH_1AY, PH_2AY, PH_3AY, and PH_4AY to other angles to obtain left-hand or right-hand elliptically polarized signals. This method allows the feed to achieve polarization scanning, thereby obtaining more comprehensive target information.

[0069] In an optional manner, the combiner ADD_1X combines the outputs of the phase shifters PH_1AX and PH_1BX;

[0070] The combiner ADD_1Y combines the outputs of the phase shifters PH_1AY and PH_1BY;

[0071] The combiner ADD_2X combines the outputs of the phase shifters PH_2AX and PH_2BX;

[0072] The combiner ADD_2Y combines the outputs of the phase shifters PH_2AY and PH_2BY;

[0073] The combiner ADD_3X combines the outputs of the phase shifters PH_3AX and PH_3BX;

[0074] The combiner ADD_3Y combines the outputs of the phase shifters PH_3AY and PH_3BY;

[0075] The combiner ADD_4X combines the outputs of the phase shifters PH_4AX and PH_4BX;

[0076] The combiner ADD_4Y combines the outputs of the phase shifters PH_4AY and PH_4BY.

[0077] In this embodiment, each combiner combines only two processed, differently polarized signals from the same dual-polarized antenna, rather than combining signals from different antennas as previously described. This provides more refined polarization control for each dual-polarized antenna. Each combiner (ADD_1X, ADD_1Y, etc.) independently combines the two polarized signals from the corresponding antenna (E1, E2, etc.), independently controlling the ultimate polarization state of each antenna at the antenna level.

[0078] In an optional manner, the feed source establishes a coordinate plane XOY with its normal direction as a reference, and the four dual-polarized antennas (E1, E2, E3 and E4) of the feed source are arranged in four quadrants of the plane XOY;

[0079] The dual-polarized antennas (E1, E2, E3, E4) are all receiving antennas and are used in conjunction with the transmitting antenna.

[0080] In this embodiment, to synthesize a differential pattern, the four antennas are evenly distributed across the four quadrants. Each antenna is dual-polarized, which helps improve the integrity of the received signal and reduce signal loss caused by polarization mismatch. The feed source can be a flat plate structure with its normal direction defined as the Z-axis. Four dual-polarized antenna units are etched or mounted on the plate, and a connector and feed network are designed on the back of the plate. The four dual-polarized antennas serve as part of the feed source, with the output of the antenna units connected to the power divider within the feed source.

[0081] In an optional embodiment, the low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, LAN_4B) are respectively connected to the polarization signals (E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, E_4B) of the corresponding dual-polarization antennas for amplifying the received polarization signals.

[0082] In this embodiment, the low-noise amplifier (LNA) can effectively amplify weak received signals and independently amplify each polarization signal to adapt to different application scenarios and environmental conditions. For example, a radar receiving front end can receive dual-polarization reflected signals from a target and amplify them through independent LNAs.

[0083] In an optional manner, the positions of the attenuator and the phase shifter in the signal transmission path can be interchanged, and the attenuator can be placed after the phase shifter.

[0084] In this embodiment, the attenuator is placed before the phase shifter to prevent excessively high-power signals from directly entering the phase shifter, reducing the risk of damage. Placing the attenuator before the phase shifter reduces the power of the signal entering subsequent circuits, thereby reducing or compensating for the nonlinear effects of the phase shifter at high power levels and simplifying circuit design and layout.

[0085] In an optional manner, the low noise amplifier is implemented by one or more stages of low noise amplifiers;

[0086] The phase shifter is realized by a single-stage or multi-stage phase shifter;

[0087] The attenuator is implemented by a single-stage or multi-stage attenuator.

[0088] In this embodiment, a multi-stage low-noise amplifier (LNA) achieves higher overall gain through multi-stage amplification, thereby amplifying weaker signals. A phase shifter, by cascading multiple stages, reduces the nonlinear effects of a single-stage phase shifter. A multi-stage attenuator provides a larger attenuation range, thus accommodating a wider range of signal strengths.

[0089] In an optional embodiment, the signals (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y) are composed of any two polarization signals (E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, E_4B) by adjusting the values of the attenuator and the phase shifter to achieve polarization adjustability.

[0090] In this embodiment, by adjusting the attenuator and phase shifter, the amplitude and phase of each polarization signal can be precisely controlled, thereby flexibly generating various required polarization states and switching between multiple polarization states without replacing hardware.

[0091] In an optional manner, the low noise amplifier, power splitter, attenuator, phase shifter, combiner and synthesis network are implemented using discrete devices or integrated devices.

[0092] In this embodiment, the best discrete components are selected based on specific requirements to achieve the highest performance. For example, a low-noise amplifier with the lowest noise or a power splitter with the highest power is selected. Integrated components are small in size and suitable for applications with limited space.

[0093] In this embodiment, the feed beam is reconstructed by continuously configuring the values of each attenuator and phase shifter, including arbitrary polarization feed, single pulse feed and conical scanning feed;

[0094] The reconstructing of the feed beam further includes:

[0095] Calculate the required adjustments for the attenuators (AT_1AX to AT_4BY) and phase shifters (PH_1AX to PH_4BY) for each dual-polarized antenna based on the target beam shape and polarization requirements.

[0096] adjusting the settings of each attenuator and phase shifter according to the adjustment value to change the amplitude and phase of each signal;

[0097] Until the required beam shape and polarization state are achieved, dynamic reconstruction of the feed beam is achieved.

[0098] The arbitrary polarization feed includes linear, circular, and elliptical polarization, and the polarization direction is adjustable. A single-pulse feed adjusts the attenuator and phase shifter to configure the feed to output sum and difference signals. The sum signal is used to receive target energy, and the difference signal indicates the deviation angle between the target and the feed normal. A conical scanning feed periodically changes the attenuator and phase shifter settings, causing the beam to scan conically in space, enabling target search and tracking.

[0099] To facilitate understanding of the above embodiments of the present invention, the following assumptions are made:

[0100] 1. The X-axis is the azimuth direction, and the Y-axis is the pitch direction.

[0101] 2. Antennas E1, E2, E3, and E4 are dual-polarization antennas. Signals E_1A, E_2A, E_3A, and E_4A are horizontally polarized signals, and signals E_1B, E_2B, E_3B, and E_4B are vertically polarized signals.

[0102] 3. Each path of the reconfigurable feed has been calibrated and the calibration values have been written. That is, when equal-amplitude and in-phase signals are input into antennas E1, E2, E3, and E4, signals A_1AX, A_1AY, A_2AX, A_2AY, A_3AX, A_3AY, A_4AX, and A_4AY are equal-amplitude and in-phase signals, and signals A_1BX, A_1BY, A_2BX, A_2BY, A_3BX, A_3BY, A_4BX, and A_4BY are equal-amplitude and in-phase signals, and the phase difference between signal A_1AX and signal A_1BX is 90°.

[0103] Example 1

[0104] Reconstruct the feed source into an arbitrary polarization feed source: UAVs usually use vertically polarized antennas to achieve ground communication. During flight, changes in the attitude of the drone will cause polarization mismatch of the tracking antenna, resulting in polarization loss of the received signal. Polarization matching is usually achieved through polarization tracking to eliminate polarization loss. To this end, the feed source needs to be able to synthesize polarization-adjustable antenna signals for back-end processing. There are currently mechanical and electronic polarization adjustment methods. The mechanical polarization adjustment method is to adjust the antenna polarization angle through a servo mechanism. The electronic polarization adjustment method is to electronically adjust the polarization angle of the two polarization signals output by the same antenna and synthesize them into one signal. This reconfigurable feed source can realize electronic polarization adjustment. The following describes the polarization tracking method using the E1 antenna as an example:

[0105] 1. Polarization Detection: Disabling power to the phase shifters PH_1AY and PH_1BX at the back end of antenna E1 will cause signal S_1X to contain only signal A_1AX, and signal S_1Y output from the feed will contain only signal A_1BY. Similarly configuring the back end circuits of antennas E2, E3, and E4 will result in the two feed output signals representing their original polarization components. The processing circuitry at the back end of the feed can simultaneously or time-sharedly detect signals S_X and S_Y to determine the polarization direction of the target signal.

[0106] 2. Synthesize Arbitrary Polarization Signals: By adjusting the attenuator and phase shifter values based on the polarization detection results, an arbitrary polarization signal can be synthesized in the feed output signal. S_1X can be configured to the desired polarization using the configuration method shown in Table 1. The configuration methods for other signal groups, such as S_1Y, are similar and will not be detailed here. Please note that the synthesizable polarization signals listed in Table 1 are only examples of a limited number. Those skilled in the art can obtain their desired arbitrary polarization signal by configuring different attenuation and phase shift values.

[0107] Table 1 Synthesizing arbitrary polarization signal configuration table

[0108]

[0109] Example 2

[0110] Reconstruct the feed into a vertically polarized four-horn monopulse feed: The monopulse radar antenna is required to generate a sum beam, an azimuth difference beam, and an elevation difference beam. The function of the sum beam is to detect the distance of the target and perform distance tracking; the function of the difference beam is to detect the azimuth error angle and elevation error angle information of the target and perform angle tracking. In this way, the spatial position of the target can be determined. The reconfigurable feed of the present invention can form two beams at the same time, so it can simultaneously form a sum beam and an azimuth difference beam, or a sum beam and an elevation difference beam, that is, two sets of sum and difference beams are formed in time-sharing, thereby realizing the detection and tracking of the target. The specific method is as follows:

[0111] 1. Synthesize vertically polarized signals S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, and S_4Y according to the method described in Example 1.

[0112] 2. Synthesized sum beam signal: If the preceding devices of signal S_X are configured according to step 1 of this embodiment, then signal S_X = S_1X + S_2X + S_3X + S_4X, which is a vertically polarized sum signal.

[0113] 3. Synthesize the azimuth difference beam signal: Configure the preceding components of signal S_Y according to step 1 of this embodiment. Then, add a 180° phase shift value to the calibrated values of phase shifters A_2BY and A_4BY. Then, signal S_Y = (S_1Y + S_4Y) - (S_2Y + S_3Y), which is the vertically polarized azimuth difference signal.

[0114] 4. Synthesize the elevation difference beam signal: Configure the upstream components of signal S_Y according to step 1 of this embodiment. Then, add a 180° phase shift value to the calibrated values of phase shifters A_3BY and A_4BY. The resulting signal S_Y = (S_1Y + S_2Y) - (S_3Y + S_4Y), which is the vertically polarized elevation difference signal.

[0115] Example 3

[0116] Reconfigure the feed into a left-handed conical scanning feed: Conical scanning tracking extracts the target's angular error information by generating a continuously rotating scanning beam, thereby determining the target's spatial position. The reconfigurable feed described in this invention can achieve beam scanning by time-sharing the four antenna elements. Specifically, the parameters of each feed channel are configured according to the order of the output antennas E1, E3, E2, and E4, thereby achieving beam scanning. The specific method is as follows:

[0117] 1. Synthesize left-hand circularly polarized signals S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, and S_4Y according to the method described in Example 1.

[0118] 2. Synthesize and beam signal: If the preceding devices of signal S_X are configured according to step 1 of this embodiment, then signal S_X = S_1X + S_2X + S_3X + S_4X, which is a left-hand circularly polarized sum signal.

[0119] 3. Synthesize scanning beam signal: The phase shifters preceding the signal S_X are configured according to step 1 of this embodiment, and then the attenuators preceding the signal S_Y are configured in sequence as shown in Table 2 to select the output signal source to achieve beam scanning.

[0120] Table 2 Synthetic scanning beam signal configuration table

[0121] Attenuator Output E1 signal Output E2 signal Output E3 signal Output E4 signal AT_1AY Activate Shutdown Shutdown Shutdown AT_1BY Activate Shutdown Shutdown Shutdown AT_2AY Shutdown Activate Shutdown Shutdown AT_2BY Shutdown Activate Shutdown Shutdown AT_3AY Shutdown Shutdown Activate Shutdown AT_3BY Shutdown Shutdown Activate Shutdown AT_4AY Shutdown Shutdown Shutdown Activate AT_4BY Shutdown Shutdown Shutdown Activate

[0122] According to the solution provided by the present invention, it includes: four dual-polarized antennas (E1, E2, E3, E4) for receiving free-space signals, wherein each dual-polarized antenna outputs two polarized signals (E_1A and E_1B, E_2A and E_2B, E_3A and E_3B, E_4A and E_4B); eight low-noise amplifiers (LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, LAN_4B), respectively connected to the polarized signals of the dual-polarized antennas, for amplifying the received polarized signals; eight power dividers (DIV _1A, DIV_1B, DIV_2A, DIV_2B, DIV_3A, DIV_3B, DIV_4A, DIV_4B), respectively connected to the output end of the low noise amplifier, for dividing the amplified signal into two paths; sixteen attenuators (AT_1AX, AT_1AY, AT_1BX, AT_1BY, AT_2AX, AT_2AY, AT_2BX, AT_2BY, AT_3AX, AT_3AY, AT_3BX, AT_3BY, AT_4AX, AT_4AY, AT_4BX, AT_4BY), respectively connected to the power divider The output end of the attenuator is connected to adjust the amplitude of the signal; sixteen phase shifters (PH_1AX, PH_1AY, PH_1BX, PH_1BY, PH_2AX, PH_2AY, PH_2BX, PH_2BY, PH_3AX, PH_3AY, PH_3BX, PH_3BY, PH_4AX, PH_4AY, PH_4BX, PH_4BY) are respectively connected to the output end of the attenuator to adjust the phase of the signal; eight combiners (ADD_1X, ADD_1Y, ADD_2X, ADD_2Y, ADD_3X, ADD_3Y, ADD_ 4X, ADD_4Y), each combiner receives two processed signals of the corresponding dual-polarized antenna and outputs a synthesized signal (S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, S_4Y); a first synthesizing network (ADD_X) is used to receive and synthesize the signals (S_1X, S_2X, S_3X, S_4X) output by the combiner and output a synthesized signal (RX); a second synthesizing network (ADD_Y) is used to receive and synthesize the signals (S_1Y, S_2Y, S_3Y, S_4Y) output by the combiner and output a synthesized signal (RY). The present invention amplifies, power divides, attenuates, phase-shifts, and synthesizes the dual-polarized antenna signals to obtain two groups of beams. Each group of beams can independently achieve amplitude weighting and phase-shift synthesis of each antenna signal, thereby realizing pattern reconstruction and polarization reconstruction.

[0123] Those skilled in the art will appreciate that modules in the devices of the embodiments may be adaptively modified and deployed in one or more devices different from the embodiments. Modules, units, or components in the embodiments may be combined into a single module, unit, or component, and furthermore, they may be divided into multiple submodules, subunits, or subcomponents. All features disclosed in this specification (including the accompanying claims, abstract, and drawings), as well as all processes or units of any method or device disclosed therein, may be combined in any combination, except where at least some of such features and / or processes or units are mutually exclusive. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that provides the same, equivalent, or similar purpose. Furthermore, those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the present invention and to form different embodiments. For example, in the claims below, any of the claimed embodiments may be used in any combination. The present invention may be implemented using hardware comprising a number of different elements and using a suitably programmed computer. In a unit claim that lists several means, several of these means may be embodied by the same hardware item. Unless otherwise specified, the steps in the above embodiments should not be understood as limiting the order of execution.

Claims

1. A reconfigurable feed, characterized in that: include: Four dual-polarized antennas E1, E2, E3, and E4 are used to receive free-space signals, wherein each dual-polarized antenna outputs two polarized signals E_1A and E_1B, E_2A and E_2B, E_3A and E_3B, and E_4A and E_4B respectively; Eight low-noise amplifiers LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, and LAN_4B are respectively connected to the polarized signals of the dual-polarized antennas and are used to amplify the received polarized signals; Eight power dividers DIV_1A, DIV_1B, DIV_2A, DIV_2B, DIV_3A, DIV_3B, DIV_4A, and DIV_4B are respectively connected to the output end of the low noise amplifier and are used to divide the amplified signal into two paths; Sixteen attenuators AT_1AX, AT_1AY, AT_1BX, AT_1BY, AT_2AX, AT_2AY, AT_2BX, AT_2BY, AT_3AX, AT_3AY, AT_3BX, AT_3BY, AT_4AX, AT_4AY, AT_4BX, and AT_4BY are respectively connected to the output end of the power divider for adjusting the amplitude of the signal; Sixteen phase shifters PH_1AX, PH_1AY, PH_1BX, PH_1BY, PH_2AX, PH_2AY, PH_2BX, PH_2BY, PH_3AX, PH_3AY, PH_3BX, PH_3BY, PH_4AX, PH_4AY, PH_4BX, and PH_4BY are respectively connected to the output end of the attenuator for adjusting the phase of the signal; Eight combiners ADD_1X, ADD_1Y, ADD_2X, ADD_2Y, ADD_3X, ADD_3Y, ADD_4X, and ADD_4Y. Each combiner receives two differently polarized signals processed by the corresponding dual-polarized antenna and outputs a combined signal S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, and S_4Y. A first combining network ADD_X is configured to receive and combine the signals S_1X, S_2X, S_3X, and S_4X output by the combiner, and output a combined signal RX; The second combining network ADD_Y is used to receive and combine the signals S_1Y, S_2Y, S_3Y, and S_4Y output by the combiner, and output a combined signal RY.

2. The reconfigurable feed according to claim 1, characterized in that: The combiner ADD_1X combines the outputs of the phase shifters PH_1AX and PH_1BX; The combiner ADD_1Y combines the outputs of the phase shifters PH_1AY and PH_1BY; The combiner ADD_2X combines the outputs of the phase shifters PH_2AX and PH_2BX; The combiner ADD_2Y combines the outputs of the phase shifters PH_2AY and PH_2BY; The combiner ADD_3X combines the outputs of the phase shifters PH_3AX and PH_3BX; The combiner ADD_3Y combines the outputs of the phase shifters PH_3AY and PH_3BY; The combiner ADD_4X combines the outputs of the phase shifters PH_4AX and PH_4BX; The combiner ADD_4Y combines the outputs of the phase shifters PH_4AY and PH_4BY.

3. The reconfigurable feed according to claim 1, characterized in that: The feed source establishes a coordinate plane XOY based on its normal direction, and the four dual-polarized antennas E1, E2, E3 and E4 of the feed source are arranged in the four quadrants of the plane XOY; The dual-polarized antennas E1, E2, E3, and E4 are all receiving antennas and are used in conjunction with the transmitting antenna.

4. The reconfigurable feed according to claim 1, characterized in that The low noise amplifiers LAN_1A, LAN_1B, LAN_2A, LAN_2B, LAN_3A, LAN_3B, LAN_4A, and LAN_4B are respectively connected to the polarized signals E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, and E_4B of the corresponding dual-polarized antennas for amplifying the received polarized signals.

5. The reconfigurable feed according to claim 1, characterized in that: The positions of the attenuator and the phase shifter in the signal transmission path are interchanged, with the attenuator being placed after the phase shifter.

6. The reconfigurable feed according to claim 1, characterized in that: The low noise amplifier is realized by one or more stages of low noise amplifier; The phase shifter is realized by a single-stage or multi-stage phase shifter; The attenuator is implemented by a single-stage or multi-stage attenuator.

7. The reconfigurable feed according to claim 1, characterized in that: The signals S_1X, S_1Y, S_2X, S_2Y, S_3X, S_3Y, S_4X, and S_4Y are composed of any two of the different polarization signals E_1A, E_1B, E_2A, E_2B, E_3A, E_3B, E_4A, and E_4B by adjusting the values of the attenuators and the phase shifters to achieve polarization adjustment.

8. The reconfigurable feed according to claim 1, characterized in that: The low noise amplifier, power divider, attenuator, phase shifter, combiner and synthesis network are realized by using discrete devices or integrated devices.

9. The reconfigurable feed according to claim 1, characterized in that: The feed can be reconstructed by configuring the values of each attenuator and phase shifter, including arbitrary polarization feed, single pulse feed and conical scanning feed; The reconstructing of the feed further includes: Calculate the required adjustment values for attenuators AT_1AX to AT_4BY and phase shifters PH_1AX to PH_4BY for each dual-polarized antenna based on the target beam shape and polarization requirements. adjusting the settings of each attenuator and phase shifter according to the adjustment value to change the amplitude and phase on each signal path; Until the required beam shape and polarization state are achieved, dynamic reconstruction of the feed is achieved.

10. The reconfigurable feed according to claim 9, characterized in that: The arbitrary polarization feed includes linear polarization, circular polarization and elliptical polarization, and the polarization direction is adjustable.

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