A mechanically synchronized phase-shifting feed device of an anisotropic width-adjusted millimeter wave ultra-wideband gap waveguide

Abstract

The application discloses a millimeter wave ultra-wideband gap waveguide mechanical synchronous phase shift feeding device with different direction width adjustment, and belongs to the technical field of microwave millimeter wave antennas. The device comprises a top layer cover plate, a middle layer, a fixed bottom plate and a movable bottom plate which are stacked, and fixed pins and movable pins are arranged alternately to form four rectangular waveguide channels. When the movable bottom plate is translated, the width of the first channel is reduced to realize phase advance, and the widths of the remaining channels are increased to realize phase delay, thereby forming different direction width adjustment and offsetting to offset nonlinear phase disturbance. The middle layer is integrated with a stepped transition, a cross transition ridge and an inclined line ridge waveguide to realize cross-layer broadband coupling and path compensation. The power divider is loaded with capacitive grooves and inductive steps, and the second stage adopts asymmetric steps and tuning columns to realize taper distribution. An electromagnetic bandgap structure is arranged at the gap to suppress leakage. The application realizes compact, low-error multi-channel synchronous phase shift in the 32-42 GHz frequency band.

Description

Technical Field

[0001] This invention belongs to the field of microwave and millimeter-wave antenna and device technology, specifically a mechanical synchronous phase-shifting feed device for millimeter-wave ultra-wideband gap waveguide with anisotropic pulse width modulation. Background Technology

[0002] In phased array antenna systems, phase shifters are the core components for achieving electronically controlled beam scanning. While active electronic phase shifting schemes offer rapid scanning capabilities, their applicability in low-to-medium real-time scenarios is limited by the high cost, significant power consumption, and thermal management challenges resulting from numerous transceiver (T / R) components in large-scale array applications. Mechanical phase shifters, with their high power capacity and low insertion loss, exhibit unique advantages in these scenarios. However, existing mechanical phase shifting structures generally face technical bottlenecks in the millimeter-wave band due to fundamental physical constraints.

[0003] First, the bandwidth limitation problem stems from the frequency-sensitive components in the structure. Traditional solutions often employ periodic chokes to suppress electromagnetic leakage in non-contact areas, but such structures based on the quarter-wavelength resonance principle can only maintain high impedance boundary conditions within a narrow band. Furthermore, the geometrical abrupt changes in the T-junction region of the waveguide power divider network excite higher-order modes, which manifest as strongly frequency-dependent parasitic reactances in the equivalent circuit, severely narrowing the impedance matching bandwidth.

[0004] Secondly, there is an inherent contradiction between increasing phase shift and achieving compactness. In the co-directional pulse width modulation scheme, to obtain a larger phase difference between adjacent ports, the slider stroke must be extended or the physical length of the channel must be increased, leading to an expansion of the overall network size. More importantly, the phase constant of the dominant mode of the rectangular waveguide has a nonlinear relationship with the width of the waveguide in the form of the inverse square root. When the width of each channel changes in the same direction, the nonlinear disturbance exhibits an algebraic cumulative effect in the calculation of the phase difference between adjacent ports, causing the equal phase characteristics within the broadband to deteriorate sharply.

[0005] Third, the sliding contact phase-shifting structure is extremely sensitive to machining tolerances and long-term reliability. The piston-type metal sliding surface is difficult to maintain ideal electrical contact during dynamic displacement, and the microscopic gaps generated by friction will cause high-frequency energy leakage and deterioration of the system's electromagnetic compatibility.

[0006] Therefore, how to achieve compact, low nonlinear error, and highly reliable multi-channel synchronous phase shifting in the millimeter-wave ultra-wideband range constitutes a technical challenge that urgently needs to be overcome in this field. Summary of the Invention

[0007] The purpose of this invention is to provide a mechanically synchronous phase-shifting feeder for millimeter-wave ultra-wideband gap waveguides with anisotropic pulse width modulation, in order to solve the problems of limited bandwidth, contradiction between volume and phase shift, and easy occurrence of sliding contact leakage in the prior art as mentioned in the background art.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device with anisotropic pulse width modulation includes: a top cover plate, an intermediate layer, a fixed base plate and a movable base plate stacked from top to bottom; the intermediate layer and the fixed base plate constitute a gap waveguide feed structure containing a one-to-four power divider. The lower surface of the intermediate layer is provided with multiple rows of fixed pins arranged along the waveguide transmission direction, and the movable base plate is provided with multiple rows of movable pins that correspond one-to-one with the fixed pins and are arranged in an alternating manner, so as to define at least four parallel rectangular waveguide transmission channels between the two; wherein, the movable base plate is used to be driven to translate laterally along the direction perpendicular to the waveguide transmission direction, so that the movable pins in at least the first channel are displaced toward the waveguide central axis to reduce their waveguide width and achieve phase lead, while the movable pins in the other channels are displaced away from the waveguide central axis to increase their waveguide width and achieve phase delay; The intermediate layer also includes a rectangular ridge waveguide vertical transition structure that connects the rectangular waveguide transmission channel to the top ridge waveguide, as well as an oblique ridge waveguide structure that is connected to each ridge waveguide to compensate for path differences caused by cross-layer spatial misalignment.

[0009] According to the above technical solution, the end of the intermediate layer is constructed into a power divider through an inductive step, a tuning post, a capacitive groove, and a fixing pin; the power divider includes a first-order power divider and a second-order power divider; the capacitive groove includes a first capacitive groove and a second capacitive groove; wherein, the first capacitive groove is disposed in the first-order power divider, and the second capacitive groove is disposed in the second-order power divider; the first capacitive groove and the second capacitive groove are used for equivalent parallel capacitance; An inductive step is provided on the side of each capacitive groove, which is used to represent an equivalent series inductance; the capacitive groove and the inductive step together form a broadband impedance matching network.

[0010] According to the above technical solution, the inductive step of the first-order power divider is a symmetrical inductive step, and the first tuning posts are provided on both sides of the symmetrical inductive step. The inductive step of the second-order power divider adopts an asymmetric inductive step, and a second tuning post is set on both sides of the asymmetric inductive step. The second tuning post has a right-angle chamfer to compensate for the difference in the inner and outer transmission paths caused by the right-angle turn of the first-order power divider and to achieve a tapered power distribution with the amplitude of the inner output port being greater than that of the outer output port.

[0011] According to the above technical solution, the movable base plate is limited by the one-dimensional translation of the guide rail in the lateral direction, and can switch between multiple discrete positions through positioning holes / slots to realize the step-by-step mechanical reconfiguration of the antenna array beam pointing.

[0012] According to the above technical solution, the movable pins include a first set of movable pins in the first channel and a second set of movable pins in the remaining channels; when the movable base plate moves in the same direction, the first set of movable pins moves toward the waveguide center axis to reduce the waveguide width of the first channel, while the second set of movable pins moves away from the waveguide center axis to increase the waveguide width of the remaining channels; thus, in the calculation of the phase difference between adjacent ports, the nonlinear disturbance of the phase-leading branch and the nonlinear disturbance of the phase-delayed branch cancel each other out at least partially due to their opposite signs.

[0013] According to the above technical solution, the rectangular ridge waveguide vertical transition structure includes a rectangular groove in the middle layer and a cross transition ridge protruding into the rectangular groove; the cross transition ridge is composed of multiple metal ridge steps with gradually varying widths, and its front end protrudes into the rectangular waveguide transmission channel at the bottom as a coupling probe, and its rear end is connected to the ridge waveguide to form a multi-section impedance transformer to realize broadband vertical coupling from the high impedance rectangular waveguide to the low impedance ridge waveguide.

[0014] According to the above technical solution, the fixed pin has a stepped transition structure at the end near the input end, and the rectangular slot opening has a chamfer near the input end. The stepped transition structure and the chamfer cooperate to form a double-section impedance transformation in the vertical direction and suppress the parasitic reactance at the vertical transition.

[0015] According to the above technical solution, the oblique ridge waveguide structure is set on the two output paths on the outside. It is tilted at a preset angle relative to the straight ridge waveguide to extend the physical length of the outer path and compensate for the difference in electrical length caused by the spatial misalignment between the wide spacing of the rectangular waveguide transmission channel and the narrow spacing of the antenna array.

[0016] According to the above technical solution, electromagnetic bandgap structures are provided on both surfaces of the fixed base plate and the intermediate layer to construct non-contact high impedance cutoff boundaries on both sides of the rectangular waveguide transmission channel, thereby suppressing electromagnetic leakage at the mechanical sliding gap.

[0017] According to the above technical solution, the operating frequency band of the power supply network covers 32-42GHz, and the initial phase error of each output port is less than 0.5° in the unshifted state.

[0018] Compared with the prior art, the present invention has the following beneficial effects: This invention achieves a compact, low-nonlinearity-error, and highly reliable multi-channel synchronous mechanical phase shifting in the 32-42GHz ultra-wideband range through a combination of an anisotropic pulse width modulation offsetting mechanism, a capacitively-loaded broadband power divider network, non-contact gap waveguide shielding, and vertical transition and oblique path compensation. This overcomes the bottlenecks of traditional mechanical phase shifters, such as bandwidth limitations, size-phase-shift inconsistencies, and sliding contact leakage. Specifically, the capacitively-loaded broadband power divider network is designed to maintain low sensitivity to equivalent load impedance changes caused by large variations in the width of the subsequent rectangular waveguide transmission channel, thus ensuring that the overall impedance matching performance of the feed network still meets system requirements even with large phase shifts. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the one-to-four gap waveguide power divider of the present invention; Figure 2 The diagram shows the return loss and insertion loss results of the 1-to-4 gap waveguide power divider of this invention. Figure 3 This is a schematic diagram of the movable pin arrangement of the present invention; Figure 4 This is a schematic diagram of the transition structure of the present invention; Figure 5 The diagram shows the return loss and insertion loss results of the transition conversion structure of this invention. Figure 6 This is a top view of the intermediate layer of the mechanical phase-shifting feeder network of the present invention; Figure 7 This is an exploded schematic diagram of the mechanical phase-shifting feeder network of the present invention; Figure 8 The diagram shows the return loss and insertion loss results of the mechanical phase-shifting feeder network of this invention. Figure 9 The phase delay from the input to the four output ports is the result of the mechanical phase-shifting feeder network of the present invention when it is not phase-shifted. Figure 10 The phase difference between adjacent ports is shown in the figure after the mechanical phase-shifting feeder network of the present invention is shifted by 1.4 mm. Figure 11 This is a top view of the intermediate layer of the mechanical phase-shifting power supply network of the present invention.

[0020] The diagram shows the following labels: 100-Top cover plate, 200-Intermediate layer, 300-Fixed base plate, 400-Modible base plate, 500-Fixed pin, 600-Modible pin, 700-Waveguide transmission channel, 701-First channel, 702-Second channel, 703-Third channel, 704-Fourth channel, 800-Rectangular ridge waveguide vertical transition structure, 801-Rectangular groove, 802-Cross transition ridge, 900-Slanted ridge waveguide structure, 110-Capacitive groove, 1101-First capacitive groove, 1102-Second capacitive groove, 111-Inductive step, 1111-Symmetrical inductive step, 1112-Asymmetric inductive step, 112-Stepped transition structure, 113-First tuning post, 114-Second tuning post, 115-Straight ridge waveguide. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1 This embodiment aims to further illustrate the key functional modules in the power supply network defined by the aforementioned claims from the perspective of technical principles and structural composition, so as to fully demonstrate its technical concept and specific implementation.

[0023] See Figure 7 The exploded view of the power supply network of the present invention shown shows a multi-layer metal stacked structure, which is assembled from top to bottom by a top cover plate 100, an intermediate layer 200, a fixed base plate 300, and a movable base plate 400 stacked sequentially. The top cover plate 100 is the top metal encapsulation layer of the power supply network, and its outer lower surface is tightly attached to the upper surface of the intermediate layer 200. In the middle part of the top cover plate 100, a preset micro-gap is maintained between the bottom surface of the top cover plate 100 and the top of the electromagnetic bandgap structure provided on the upper surface of the intermediate layer 200. The flat lower surface of the top cover plate 100, the aforementioned preset micro-gap, the electromagnetic bandgap structure, and the ridge structure opened in the intermediate layer 200 together constitute a complete gap ridge waveguide transmission structure.

[0024] The intermediate layer 200 is the core structural layer of the feed network. Its upper surface has channels to accommodate the ridge waveguide, while its lower surface is precision-machined to form an array of multiple rows of fixed pins 500 arranged along the waveguide transmission direction, as well as the upper half of a capacitive groove 110 located in the power distribution region. A fixed base plate 300 is fixedly disposed relative to the intermediate layer 200. Its upper surface is machined with periodically arranged electromagnetic bandgap structures and the lower half of the capacitive groove 110. A small and constant gap (e.g., 0.05 mm, preferably 0.02 mm to 0.1 mm) is maintained between the upper surface and the lower surface of the intermediate layer 200 to ensure that the electromagnetic bandgap structure forms an effective high-impedance cutoff boundary within the operating frequency band. A movable base plate 400 is slidably disposed below the fixed base plate 300. Its upper surface is machined with multiple rows of movable pins 600, each corresponding to one of the fixed pins 500 and arranged in an alternating pattern. Constrained by the transverse guide rail, the movable base plate 400 can only perform one-dimensional translational movement along an axis perpendicular to the waveguide transmission direction. Its translational displacement is precisely locked between multiple discrete physical positions by three rows of staggered mechanical positioning holes and slots located between the fixed layer and the movable base plate, in conjunction with positioning pins, to achieve step-by-step mechanical reconfiguration of the antenna array beam pointing. This layered architecture spatially decouples the fixed power distribution network from the sliding phase-shifting actuator. The relative sliding gap between the fixed base plate 300 and the movable base plate 400 provides a non-contact, high-impedance electromagnetic shielding boundary through an electromagnetic bandgap structure, effectively blocking the transverse leakage of electromagnetic energy from the sliding gap between the fixed pin 500 and the movable pin 600 without physical contact.

[0025] The signal input terminal adopts a standard WR-22 rectangular waveguide interface. Electromagnetic energy first enters the power distribution region of the gap waveguide defined by the lower surface of the intermediate layer 200 and the upper surface of the fixed base plate 300. Within this region, periodic electromagnetic bandgap structures are arranged on the opposing surfaces of the fixed base plate 300 and the intermediate layer 200. This structure creates a cutoff boundary with high surface impedance characteristics on both sides of the rectangular waveguide transmission channel 700, so that even if there is a physical gap between the fixed base plate 300 and the movable base plate 400 due to mechanical sliding in the operating frequency band of 32-42GHz, lateral electromagnetic leakage can still be effectively suppressed.

[0026] like Figure 11 As shown, the four-power divider is constructed using a cascaded two-order branch topology. See also... Figure 1At the first-order power divider, a first capacitive groove 1101 is formed along the wide side of the waveguide. The first capacitive groove 1101 is a rectangular groove with rounded corners on all four sides. When electromagnetic waves propagate to the region of the first capacitive groove 1101, the local height of the waveguide changes abruptly. The electric field is highly concentrated at the right-angled edge of the abrupt change, generating an edge effect and accumulating charge, thus forming a parallel capacitor in the equivalent circuit. At the center of the branch junction region, an inductive step 111 protrudes into the waveguide. This inductive step 111 is composed of a metal boss, which blocks part of the longitudinal flow of high-frequency surface current, forcing the current to detour. This causes the magnetic field to concentrate near the step, storing additional magnetic field energy, which manifests as a series inductance in the equivalent circuit. The first capacitive groove 1101 and the inductive step 111 together form a distributed parameter multi-order impedance matching network, which performs broadband compensation for the parasitic reactance excited by the geometric change in the T-junction region. The second-order power divider, building upon the aforementioned capacitive-inductive loading structure, further introduces an asymmetric inductive step 1112 and first and second tuning pillars 113 and 114 with differentiated chamfer dimensions. This asymmetric geometry refers to the fact that, with the central axis of the main transmission line of the T-shaped branch as a reference, the step deformation and chamfer depth of the asymmetric inductive step 1112 at the connection points of the left and right output branches are different, presenting an asymmetric trapezoidal profile. This design aims to reverse-compensate for the difference in transmission paths between the inner and outer sides introduced by the right-angle turn of the first-order power divider, while simultaneously achieving a tapered power distribution with the inner output port amplitude slightly higher than the outer output port, thus serving the sidelobe suppression requirements of the antenna array.

[0027] The four signals output from the power divider enter four parallel rectangular waveguide transmission channels defined by the fixed pin 500 on the lower surface of the intermediate layer 200 and the movable pin 600 on the upper surface of the movable base plate 400, namely, the first channel 701, the second channel 702, the third channel 703, and the fourth channel 704. The propagation characteristics of the dominant mode of the rectangular waveguide are dominated by the width dimension of the waveguide, and its phase constant decreases monotonically and exhibits a nonlinear relationship as the width increases. This invention constructs an anisotropic pulse width modulation mechanism that links phase lead and phase delay by differentially setting the position layout of the movable pins 600 of each channel relative to the waveguide central axis. Specifically, the movable pin 600 of the first channel 701 is arranged on the left side wall of the waveguide channel, and the movable pins 600 of the other three channels 702, 703, and 704 are arranged on the right side wall of their respective waveguide channels. When the movable base plate 400 is driven to translate laterally in the same direction, the movable pins 600 in the first channel 701 move closer to the waveguide center, causing the channel width to contract, while the movable pins 600 in the other channels move away from the waveguide center, causing the corresponding channel width to expand. Since the first channel 701 operates on the narrowing side of the propagation constant-waveguide width curve, and the other channels operate on the widening side of the curve, the nonlinear phase disturbances generated by each channel cancel each other out when calculating the phase difference between adjacent ports due to their opposite algebraic signs, thus maintaining excellent equal-arithmetic phase linearity over a wide bandwidth. This anisotropic phase width modulation mechanism significantly increases the achievable phase difference range between adjacent ports without increasing the total length of the feed network or the travel of the movable base plate 400.

[0028] The rectangular waveguide phase-shifting structure is located at the bottom layer of the feed network, while the antenna array elements need to be arranged at a narrower spacing on the top layer to meet the grating lobe-free scanning condition. There is a significant spatial span and positional misalignment between the two. To solve the cross-layer path compensation problem between the wide-spacing input at the bottom layer and the narrow-spacing output at the top layer, this invention integrates a rectangular ridge waveguide vertical transition structure 800 and a diagonal ridge waveguide structure 900 within the intermediate layer 200. The rectangular ridge waveguide vertical transition structure 800 includes a rectangular slot 801 formed in the intermediate layer 200 and a cross-shaped transition ridge 802 extending into the rectangular slot 801. A two-stage stepped transition structure 112 is provided at the end of the fixing pin 500 near the input end. This stepped transition structure 112 is composed of two series-connected rectangular steps with gradually changing heights, equivalent to a two-section impedance transformer. The opening of the rectangular slot 801 is chamfered near the input end. This chamfer, in conjunction with the stepped transition structure 112, forms a two-section impedance transformer in the vertical direction to suppress parasitic reactance caused by geometric abrupt changes at the vertical transition point. The cross-shaped transition ridge 802 comprises multiple metal ridge segments with stepped widths and lengths. Its front end extends into the bottom rectangular waveguide cavity to form an E-plane coupling probe. Subsequent ridge segments smoothly transition from a high-impedance rectangular waveguide mode to a low-impedance ridge waveguide mode through multi-section impedance transformation. After electromagnetic energy is vertically coupled to the upper ridge waveguide, the ridge waveguides of the two outer channels are designed as oblique ridge waveguide structures 900 with a preset tilt angle. This oblique ridge waveguide structure 900 is tilted at a certain angle relative to the straight ridge waveguide 115, precisely compensating for the electrical length inconsistency caused by the difference in spatial position between the inner and outer sides by extending the physical length of the outer path. This combined structure ensures that the initial phase error between the four output ports is strictly controlled within 0.5° when no phase shifting operation is applied.

[0029] Example 2 This embodiment is combined with the appendix Figures 1 to 10 This paper presents a specific example of the aforementioned power supply network implemented in the 32GHz to 42GHz frequency band to further verify its technical effectiveness and feasibility.

[0030] See Figure 7The exploded view shown illustrates that the feed network in this example is assembled from four layers: a top cover plate 100, an intermediate layer 200, a fixed base plate 300, and a movable base plate 400. The fixed base plate 300 and the movable base plate 400 together form the bottom sliding assembly of the network. The movable base plate 400 is confined within a transverse guide rail and can only perform one-dimensional translational movement perpendicular to the waveguide transmission direction. To achieve discrete beam reconfiguration, three rows of staggered mechanical positioning holes are provided between the movable base plate 400 and the fixed layer. Operators manually push and pull the movable base plate 400 and lock it at a preset scale position using positioning pins. This example sets up twelve discrete translation positions, with corresponding displacements of -0.8mm, -0.6mm, -0.4mm, -0.2mm, 0mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm and 1.4mm respectively. The positive displacement is defined as the rightward translation of the movable base plate 400.

[0031] The specific geometric parameters of the power divider section are as follows. See below. Figure 1 The first capacitive groove 1101 at the first-order power divider has physical dimensions of 3.2 mm in length, 4.3 mm in width, and 0.9 mm in depth, with all four sides rounded with a radius of 0.5 mm. The second capacitive groove 1102 at the second-order power divider has physical dimensions of 3.8 mm in length, 3.1 mm in width, and 0.85 mm in depth, with all four sides also rounded with a radius of 0.5 mm. The inductive step 111 of the first-order power divider is a symmetrical inductive step 1111; the asymmetrical inductive step 1112 of the second-order power divider has a length of 2.2 mm and a width of 1.3 mm along the transmission direction, with chamfer dimensions of 0.6 mm and 1.6 mm on its left and right sides, respectively. Figure 2 Simulation results of the scattering parameters of the power divider in the 32GHz to 42GHz frequency band are given: the input return loss is better than -20dB throughout the entire frequency band; the amplitude of the transmission coefficient fluctuates between -6.25dB and -5.92dB, and the transmission amplitude of the inner port is slightly higher than that of the outer port, showing the expected tapered distribution characteristics; the total insertion loss is less than 0.45dB.

[0032] The movable pins of the phase-shifting structure are arranged as follows: Figure 3As shown, with the feed network viewed from above and the input terminal located below as the orientation reference, 20 movable pins 600 are set on the left wall of the waveguide channel corresponding to port 1 (first channel 701), 11 movable pins 600 are set on the right wall of the waveguide channel corresponding to port 2 (second channel 702), 3 movable pins 600 are set on the right wall of the waveguide channel corresponding to port 3 (third channel 703), and 3 movable pins 600 are set on the right wall of the waveguide channel corresponding to port 404 (fourth channel 704). The different number of pins in each channel results in different waveguide width variation gradients for different channels under the same translation of the movable base plate 400, thereby achieving the required equal phase distribution between the output ports. When the movable base plate 400 is translated to the right to the maximum positive displacement of 1.4mm, the waveguide width of the first channel 701 decreases to approximately 4.3mm, while the waveguide widths of the second to fourth channels 704 increase accordingly. Figure 10 The frequency response curve of the phase difference between adjacent output ports under the maximum phase shift state is shown. The phase difference between adjacent ports is stably maintained at about 120° in the range of 32GHz to 42GHz, with very small fluctuations, which strongly confirms that the anisotropic pulse width modulation mechanism effectively offsets and suppresses the error caused by the nonlinearity of the phase constant.

[0033] For implementation details of the vertical transition structure, please refer to Figure 4 The fixed pin 500 has a two-stage stepped transition structure 112 near the input end. This stepped transition structure 112 is composed of two rectangular steps connected in series, each with a width of 2.25 mm and heights of 1.1 mm and 0.9 mm respectively, equivalent to a two-section impedance transformer. The rectangular slot 801 in the intermediate layer 200 has a chamfered opening near the input end, with chamfer dimensions of 0.5 mm and 0.65 mm respectively. The cross-shaped transition ridge 802 is composed of four metal ridge segments. From the front end to the rear end of the waveguide cavity, the ridge widths are 1.3 mm, 1.9 mm, 5.5 mm, and 1.9 mm respectively, and the corresponding ridge lengths are 1.2 mm, 1.0 mm, 0.8 mm, and 2.3 mm respectively. These four stepped ridge segments constitute a multi-section impedance transformer, utilizing the phase cancellation effect of reflected waves at each step to achieve broadband vertical coupling from the high-impedance rectangular waveguide to the low-impedance ridge waveguide. Figure 5 The simulation results show that the transition structure has an input return loss better than -20dB in the 32GHz to 41GHz band and better than -15dB in the 41GHz to 42GHz band, with an insertion loss of less than 0.12dB.

[0034] For implementation details of the path compensation structure, please refer to Figure 6The ridge waveguides of the two middle channels employ a transmission path composed of three cascaded straight ridge waveguide segments 115 with lengths of 6.5mm, 3mm, and 14mm respectively. The ridge waveguides of the two outer channels are designed as oblique ridge waveguide structures 900, deflected by 26° relative to the straight ridge waveguides 115, with a total length of 22.4mm. This oblique ridge waveguide structure 900 precisely compensates for the electrical length difference caused by the spatial misalignment between the wide spacing of the rectangular waveguide transmission channels 700 and the narrow spacing of the antenna array by extending the physical path. When the movable base plate 400 is in the zero-displacement position, Figure 9 The phase delay simulation results shown indicate that the transmission phase curves of the four output ports are highly coincident across the entire frequency band, with an initial phase error of less than 0.5°. This fully verifies the accurate compensation capability of the 900-degree sloping ridge waveguide structure for path differences caused by spatial misalignment.

[0035] Figure 8 The overall scattering parameter performance of the feed network in this example is demonstrated in the 32GHz to 42GHz frequency band: the input return loss is better than -17.5dB, the amplitude consistency of the transmission coefficients of each output port is good, and the total insertion loss, including power division, phase shift and vertical transition, is less than 0.9dB.

[0036] In summary, this invention achieves a compact, low-nonlinear-error, and highly reliable multi-channel synchronous mechanical phase-shifting feeder in the 32-42GHz ultra-wideband range through a broadband impedance matching network composed of capacitive groove 110 and inductive step 111, tapered power distribution achieved by the first tuning post 113 and the second tuning post 114 in conjunction with the asymmetric inductive step 1112, a phase lead-delay counterbalancing mechanism achieved by the opposite arrangement of fixed pin 500 and movable pin 600, a non-contact high-impedance cutoff boundary constructed by an electromagnetic bandgap structure, a broadband vertical coupling module composed of stepped transition structure 112 and cross transition ridge 802, and path precision compensation achieved by oblique ridge waveguide structure 900.

[0037] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural modifications made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

[0038] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0039] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device with anisotropic pulse width modulation, characterized in that: include: The structure consists of a top cover plate (100), an intermediate layer (200), a fixed base plate (300), and a movable base plate (400) stacked from top to bottom; the intermediate layer (200) and the fixed base plate (300) together form a gap waveguide feeding structure containing a one-to-four power divider. The lower surface of the intermediate layer (200) is provided with multiple rows of fixed pins (500) arranged along the waveguide transmission direction, and the movable base plate (400) is provided with multiple rows of movable pins (600) that correspond one-to-one with the fixed pins (500) and are arranged in an alternating manner, so as to define at least four parallel rectangular waveguide transmission channels (700) between the two. The movable base plate (400) is driven to translate laterally along the direction perpendicular to the waveguide transmission direction, so that the movable pin (600) in at least the first channel (701) is displaced toward the waveguide central axis to reduce its waveguide width and achieve phase lead, while the movable pin (600) in the other channels is displaced away from the waveguide central axis to increase its waveguide width and achieve phase delay. The intermediate layer (200) also includes a rectangular ridge waveguide vertical transition structure (800) that connects the rectangular waveguide transmission channel (700) to the top ridge waveguide, and a slanted ridge waveguide structure (900) that is connected to each ridge waveguide to compensate for the path difference caused by the cross-layer spatial misalignment.

2. The anti-directional width modulation millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: The end of the intermediate layer (200) is constructed into a power divider through an inductive step (111), a tuning post, a capacitive groove (110), and a fixing pin (500); the power divider includes a first-order power divider and a second-order power divider; the capacitive groove (110) includes a first capacitive groove (1101) and a second capacitive groove (1102); wherein, the first capacitive groove (1101) is disposed in the first-order power divider, and the second capacitive groove (1102) is disposed in the second-order power divider; the first capacitive groove (1101) and the second capacitive groove (1102) are used for equivalent parallel capacitance; An inductive step (111) is provided on the side of each capacitive groove (110), and the inductive step (111) is used as an equivalent series inductance; the capacitive groove (110) and the inductive step (111) together form a broadband impedance matching network.

3. The anti-directional width-adjusting millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 2, characterized in that: The inductive step (111) of the first-order power divider is a symmetrical inductive step (1111), and the first tuning column (113) is provided on both sides of the symmetrical inductive step (1111). The inductive step (111) of the second-order power divider adopts an asymmetric inductive step (1112), and a second tuning post (114) is provided on both sides of the asymmetric inductive step (1112). The second tuning post (114) has a right-angle chamfer to compensate for the difference between the inner and outer transmission paths caused by the right-angle turn of the first-order power divider and to realize the tapered power distribution with the amplitude of the inner output port being greater than that of the outer output port.

4. The anti-directional width-adjusting millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: The movable base plate (400) is limited by the one-dimensional translation of the guide rail in the lateral direction and can switch between multiple discrete positions through positioning holes / slots to achieve step-by-step mechanical reconfiguration of the antenna array beam pointing.

5. The anti-directional width modulation millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 4, characterized in that: The movable pin (600) includes a first set of movable pins located in the first channel (701) and a second set of movable pins located in the remaining channels. When the movable base plate (400) is translated in the same direction, the first set of movable pins is displaced toward the waveguide center axis to reduce the waveguide width of the first channel (701), while the second set of movable pins is displaced away from the waveguide center axis to increase the waveguide width of the remaining channels. As a result, in the calculation of the phase difference between adjacent ports, the nonlinear disturbance of the phase-leading branch and the nonlinear disturbance of the phase-delayed branch cancel each other out at least partially due to their opposite signs.

6. The anti-directional width modulation millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: The rectangular ridge waveguide vertical transition structure (800) includes a rectangular slot (801) formed in the intermediate layer (200) and a cross transition ridge (802) extending into the rectangular slot (801). The cross transition ridge (802) is composed of multiple metal ridge steps with gradually varying widths. Its front end extends into the rectangular waveguide transmission channel (700) at the bottom as a coupling probe, and its rear end is connected to the ridge waveguide to form a multi-section impedance transformer to realize broadband vertical coupling from the high-impedance rectangular waveguide to the low-impedance ridge waveguide.

7. The anti-directional width-adjusting millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 6, characterized in that: The fixed pin (500) has a stepped transition structure (112) at the end near the input end, and the rectangular slot (801) has a chamfer at the opening near the input end. The stepped transition structure (112) and the chamfer cooperate to form a double-section impedance transformation in the vertical direction and suppress the parasitic reactance at the vertical transition.

8. The anti-directional width modulation millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: The oblique ridge waveguide structure (900) is set on the two output paths on the outside. It is tilted at a preset angle relative to the straight ridge waveguide (115) to extend the physical length of the outer path and compensate for the difference in electrical length caused by the spatial misalignment between the wide spacing of the rectangular waveguide transmission channel (700) and the narrow spacing of the antenna array.

9. The anti-directional width-adjusted millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: A certain gap is left on the two surfaces opposite to the fixed base plate (300) and the intermediate layer (200) to form an electromagnetic bandgap structure, so as to build a non-contact high impedance cutoff boundary on both sides of the rectangular waveguide transmission channel (700) and suppress electromagnetic leakage at the mechanical sliding gap.

10. The anti-directional width modulation millimeter-wave ultrawideband gap waveguide mechanical synchronous phase-shifting feed device according to claim 1, characterized in that: The operating frequency band of the power supply network covers 32-42GHz, and the initial phase error of each output port is less than 0.5° in the un-phase-shifted state.

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