A half-mode substrate integrated waveguide phase shifter based on loaded h-shaped capacitive structure

Abstract

The application discloses a half-mode substrate integrated waveguide phase shifter based on a loaded H-shaped capacitor structure, which is composed of an HMSIW transmission main body, a periodic meander line slot, an H-shaped metal patch, a varactor diode and a DC bias network; the phase shifter introduces a slow wave effect by etching a periodic meander line slot on the top layer, and enhances the equivalent capacitance by using an H-shaped metal structure, so as to further strengthen the slow wave characteristics; at the same time, by adjusting the DC bias voltage to change the capacitance value of the varactor diode, the propagation constant is adjusted, and continuous phase adjustment is realized. Test results show that the reflection coefficient of the phase shifter is better than -10 dB in the 5-6 GHz frequency band, and a single unit can realize about 100° continuous linear phase shift at the center frequency of 5.5 GHz, and four units in cascade can realize 360° full-period phase coverage. The application has the advantages of compact structure, simple control and the like, and is suitable for C-band phased array beam scanning systems.

Description

Technical Field

[0001] This invention relates to the application field of active phase shifters, and in particular to a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure. Background Technology

[0002] With the rapid development of wireless communication technology, especially the increasing demands for dynamic multi-target tracking in space from 5G / 6G communication, vehicle-mounted radar, and satellite terminals, phased array systems have become crucial for achieving high-speed data transmission and flexible beam scanning. As the core radio frequency (RF) device in a phased array system, the phase shifter directly determines the system's pointing accuracy, scanning range, and radiation efficiency by precisely controlling the phase difference between antenna elements. With the trend towards higher integration, lower power consumption, and lower cost in RF front-ends, developing continuously adjustable phase shifters with a large phase shift range, low insertion loss, and wide bandwidth characteristics within limited physical space has become a research hotspot in microwave engineering.

[0003] Among existing phase shifter designs, loaded linear phase shifters are favored due to their compact structure, low insertion loss, and ease of achieving continuous phase modulation. However, traditional structures still face significant challenges in practical applications. First, there is a severe trade-off between phase shift and physical size; single-stage loaded structures struggle to provide sufficient phase shift range, while multi-stage cascading leads to a dramatic increase in device size. Second, although half-mode substrate integrated waveguide (HMSIW) technology offers significant advantages in miniaturization, balancing return loss and large-range phase shift is often difficult when introducing varactor diodes for continuous phase modulation. Therefore, effectively enhancing the slow-wave effect by introducing specific capacitor-loaded structures to achieve large-range continuous phase modulation within a very small size is of significant technical importance for promoting the development of high-performance phased array systems towards high integration. Summary of the Invention

[0004] The purpose of this invention is to provide a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure, which provides a solution to the problems of miniaturization, large phase shift, and low insertion loss that existing active phase shifters cannot simultaneously achieve. The working principle of this active adjustable phase shifter is explained in conjunction with the equivalent circuit model and field distribution characteristics.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure, comprising a dielectric substrate, a first metal structure printed on the bottom of the dielectric substrate, a second metal structure printed on the top of the dielectric substrate, a metal via structure distributed in the dielectric substrate, a 30nH choke inductor soldered to the upper surface of the dielectric substrate, a varactor diode soldered to the upper surface of the dielectric substrate, and pin headers soldered to the dielectric substrate; the first metal structure is composed of a grounding structure and a lower grounding line; the second metal structure is composed of a microstrip transmission line, a meandering line slot etched on the surface of the metal structure, an H-type metal patch, and an upper bias line; the cascaded phase shifter is composed of four identical phase shifter units connected in series.

[0006] Furthermore, a varactor diode is connected between the H-type metal patch and the microstrip transmission line, and a DC bias network consisting of a 30nH choke inductor, a lower ground line, and an upper bias line is formed. The digital control board adjusts the bias voltage through pin headers to change the capacitance of the varactor diode, thereby controlling the phase constant of the transmission line.

[0007] Furthermore, the dielectric substrate is made of Rogers RT / duroid 5880 and has dimensions of 30mm*65.5mm*0.258mm; the bottom and top metal structures of the dielectric substrate are both made of copper with a thickness of 0.035mm.

[0008] Furthermore, the metal via structure is a 1*9 metal via array, with each metal via having a diameter of 0.5mm. The metal vias are arranged periodically along the y-direction with a center spacing of 1.52mm, with the long side of the rectangular substrate as the y-direction, the short side as the x-direction, and the direction perpendicular to the dielectric substrate plane as the z-direction. The total number of metal vias is 9.

[0009] Furthermore, the 30nH choke inductor is welded along the x-direction with a welding spacing of 0.46mm.

[0010] Furthermore, the varactor diodes are arranged periodically along the y-direction with a center spacing of 3.6mm, and the number is 9. They are welded along the x-direction with a welding spacing of 0.75mm.

[0011] Furthermore, the pin header is a 2*4 pin header structure, which is welded perpendicularly along the z-direction.

[0012] Furthermore, the grounding structure is a rectangular structure with dimensions of 20mm*65.5mm.

[0013] Furthermore, the lower grounding wire connects the anode of the varactor diode to the grounding terminal of the digital control board.

[0014] Furthermore, the microstrip transmission line has a length of 21.5 mm, wherein the narrow end of the impedance transformation structure has a width of 1.4 mm and the wide end has a width of 2.9 mm.

[0015] Furthermore, the meandering line gaps are periodically arranged along the x-direction with a center spacing of 1.6mm, and there are 5 gaps in total, each with a size of 0.8mm*12mm.

[0016] Furthermore, the H-shaped metal patches are arranged periodically along the y-direction with a center spacing of 3.6mm, and there are 9 of them. The overall size of the H-shaped metal patches is 2mm*3mm, and the four gaps etched on them are the same size, all of which are 0.8mm*0.3mm.

[0017] Furthermore, the upper bias line connects the cathode of the varactor diode to the power input terminal of the digital control board.

[0018] Furthermore, the cascaded phase shifter is composed of four identical phase shifter units connected in series, with adjacent phase shifter units arranged along the y-direction and the center-to-center distance between adjacent phase shifter units being 52mm.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] (1) In view of the problem that traditional phase shifters are large in size and difficult to meet the requirements of high-density integration, this invention proposes a slow wave structure with half-mode substrate integrated waveguide combined with H-type patch loading. By enhancing the slow wave effect, the lateral size of the device is significantly reduced, thereby realizing the miniaturization design of the phase shifter.

[0021] (2) In view of the problem that traditional loaded linear phase shifters are prone to impedance mismatch and limited phase shift range during the tuning process, this invention proposes a scheme to generate static distributed capacitance using H-type structure, thereby achieving the effect of 100° continuous phase control while maintaining good reflection coefficient in the full tuning range.

[0022] (3) Through the four-unit cascaded structure, 360° full phase coverage is achieved under the premise of compact structure, which meets the application requirements of phased array system for wide-angle beam scanning, and has the advantages of simple control and easy engineering implementation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention.

[0024] Figure 2 This is an equivalent circuit diagram of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention.

[0025] Figure 3This is an electric field distribution diagram of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention.

[0026] Figure 4 This is a simulation diagram of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention.

[0027] Figure 5 The simulation response curves of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of this invention are shown in the continuous tuning range of the varactor diode capacitance value from 0.35 pF to 3.2 pF, representing the reflection coefficient, transmission coefficient and phase shift range.

[0028] Figure 6 This invention provides a physical fabrication and testing scheme for the unit structure of a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure.

[0029] Figure 7 The test results curves for the reflection coefficient, transmission coefficient, and phase shift range of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention are shown in the continuous tuning range of the varactor diode capacitance value from 0.35 pF to 3.2 pF.

[0030] Figure 8 This is a simulation diagram of a four-unit cascaded phase shifter based on a half-mode substrate integrated waveguide phase shifter with a loaded H-type capacitor structure, according to the present invention.

[0031] Figure 9 The simulation response curves of the reflection coefficient, transmission coefficient and phase shift range of the four-unit cascaded structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention are shown in 16 working modes from full reference state (0000) to full phase shift state (1111).

[0032] Figure 10 This invention provides a fabrication and testing scheme for a four-unit cascaded phase shifter based on a half-mode substrate integrated waveguide phase shifter with a loaded H-type capacitor structure.

[0033] Figure 11 The test results curves of the reflection coefficient, transmission coefficient and phase shift range of the four-unit cascaded structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure of the present invention are shown in 16 working modes from full reference state (0000) to full phase shift state (1111). Detailed Implementation

[0034] In recent years, developing high-performance phase shifters using substrate integrated waveguide (SIW) technology has become a key approach to realizing broadband, low-loss RF front-ends. In applications such as phased array systems, traditional passive phase shifters typically achieve specific phase shifts by changing physical geometry. However, in practical applications, this approach often faces drawbacks such as fixed phase shift states, lack of flexibility, and difficulty in achieving dynamic beam scanning, making the system unable to adapt to complex communication environments in real time. Meanwhile, although some active tunable solutions have been proposed, most suffer from complex tuning circuits, excessive insertion loss, and difficulties in maintaining structural compactness and good impedance matching after loading active devices. The ability to simultaneously achieve wide-range continuous phase adjustment, miniaturized integration, and a large phase shift range with an active tunable phase shifter has become a major challenge in current microwave integration technology research.

[0035] To address the aforementioned challenges, this invention provides a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure, with the unit structure as follows: Figure 1 As shown, the phase shifter unit structure mainly consists of a half-mode substrate integrated waveguide transmission body, a meandering line slot etched on the top metal surface, an H-type metal patch, a varactor diode, and a DC bias network. By setting a half-mode substrate integrated waveguide transmission structure, consisting of a metal via array 4, a bottom metal 2, and a top metal 3, within the dielectric substrate 1 as the energy transmission carrier, and periodically etching meandering line slots 11 into the top metal structure 3 to form a slow-wave structure, and utilizing the stable static distributed capacitance formed between the H-type patch 12 and the bottom metal structure 2 to dominate the slow-wave effect of the circuit, the waveguide wavelength is significantly reduced and the device is miniaturized. On this basis, a varactor diode 6 is connected between the H-type metal patch 12 and the main transmission structure, and a DC bias network consisting of a 30nH choke inductor 5, a lower ground line 9, and an upper bias line 13 is formed. The digital control board adjusts the bias voltage through the pin header 7 to change the capacitance of the varactor diode 6, thereby controlling the phase constant of the transmission line. This allows the electromagnetic wave to obtain a wide range of continuous phase changes when passing through this periodically loaded structure, ultimately achieving precise control of the output signal phase.

[0036] Energy is fed into the half-mode substrate integrated waveguide from the input end and propagates along the y-direction within the quasi-waveguide cavity, generating strong electromagnetic coupling with the top-layer meandering line slot and the H-type metal patch. By adjusting the bias voltage of the varactor diode, the equivalent load capacitance of the H-type metal patch is dynamically changed, thereby effectively controlling the phase velocity of the electromagnetic wave within the waveguide using the slow-wave effect, achieving continuous phase adjustment of the output signal. Finally, through a four-unit cascaded structural layout, 360° full-cycle continuous phase shift coverage is achieved while ensuring good impedance matching.

[0037] First, the design of the phase shifter unit structure, such as Figure 1As shown. Rogers RT / duroid 5880 was selected as the dielectric substrate. The main body dimensions of the half-mode substrate integrated waveguide transmission are 11.44mm*65.5mm*0.258mm. Five meandering line slots, etched on the surface of the top metal structure, are periodically arranged along the x-direction with a center spacing of 1.6mm. Each slot is 0.8mm*12mm in size. Their core function is to introduce a slow-wave effect by extending the surface current path, thereby controlling the phase velocity without increasing the physical length. The overall size of the H-shaped metal patch is 2mm*3mm. Four slots with identical dimensions (0.8mm*0.3mm) are etched on it, with a center spacing of 3.6mm along the y-direction. Nine varactor diodes are arranged in a directional pattern to enhance the structural equivalent capacitance and maintain impedance matching stability. Nine varactor diodes are periodically arranged along the y-direction with a center spacing of 3.6 mm, and welded along the x-direction with a welding spacing of 0.75 mm. The slow wave effect is enhanced by dynamically adjusting the capacitance of the varactor diodes, thereby achieving phase control. In the DC bias network, the upper bias line feeds positive voltage into the cathode of the varactor diode, and the lower ground line is interconnected with the anode of the varactor diode through nine metallized vias with a diameter of 0.5 mm and a center spacing of 3.6 mm in the half-mode substrate integrated waveguide transmission body, thus constructing a complete DC loop.

[0038] like Figure 2 As shown, the lumped-parameter equivalent circuit model of a half-mode substrate integrated waveguide phase shifter unit with a loaded H-type capacitor structure is presented. This model consists of the main transmission line and its loaded parallel branches, and the lumped element parameters in the circuit have a clear correspondence with the geometric dimensions of the physical structure. The inductance in the series branch of the model... The equivalent inductance of the interdigitated structure on the unit cell is characterized. Physically, this inductance is primarily determined by the path distribution of the surface current flowing through the integrated waveguide metal layer on the half-mode substrate. The introduction of the H-type capacitor structure alters the surface current distribution, extending its path and thus manifesting as a series capacitor in the circuit model. The increase. The parallel branch mainly includes the capacitance of the varactor diode. and interdigital capacitors According to microwave transmission line theory, the characteristic impedance of this structure is... and phase constant They can be represented as:

[0039]

[0040]

[0041] Among them, the total equivalent inductance Mainly composed of Contribution, total equivalent capacitance Approximately from , and varactor diode capacitor It is formed by superposition. In the phase constant... middle, Let be the angular frequency of the input signal, and When the operating frequency is determined, it can be considered a constant. Therefore and The introduction of this will increase the total equivalent inductance and total equivalent capacitance, and make the phase constant... Increasing the length of the object achieves the slow wave effect while keeping the physical length constant, while changing the length of the object... That is, the phase constant can be made The change occurs, thus achieving a phase-shifting effect. Furthermore, due to the interdigitated capacitance... The value is much larger than the capacitance of the varactor diode. , It dominates the total capacitance, which makes the characteristic impedance right The phase shifter is insensitive to changes in impedance, thus ensuring impedance matching characteristics throughout the entire tuning range.

[0042] Finally, to further explain the working principle of the phase shifter unit... Figure 3 From left to right, the low capacitance values ​​of the varactor diodes are visually displayed. 0.35pF) and high value state ( The electric field distribution at 3.2 pF is shown in the simulation results. Observing the simulation results, it can be found that the strong electric field region is not uniformly distributed throughout the entire substrate dielectric, but is significantly concentrated in the narrow region between the top H-type capacitor structure and the bottom ground plane. Further comparison of the transmission characteristics under the two extreme states shows that adjusting the value of the varactor diode capacitance directly determines the intensity of the electromagnetic wave in the H-type structure region. When the loaded capacitance is tuned to 0.35 pF, the additional capacitive load introduced into the H-type structure region is small, and the electromagnetic wave mainly propagates along the interdigitated capacitor structure, exhibiting a relatively fast phase velocity. However, as the loaded capacitance increases to 3.2 pF, the electric field distribution changes significantly, and the electromagnetic energy mainly propagates along the H-type patch structure. According to slow wave theory, the dramatically increased capacitive load forces a significant decrease in the group velocity of the electromagnetic wave, resulting in a shorter wavelength. Consequently, it experiences more phase periods over the same physical transmission distance, producing a large phase lag.

[0043] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0044] Example

[0045] Reference Figure 4This is a simulation diagram of the unit structure of the half-mode substrate integrated waveguide phase shifter based on the loaded H-type capacitor structure implemented in this invention. The structure uses an SMA connector for power feeding. Energy is fed into the microstrip transmission line through the SMA connector, and after passing through the impedance transformation structure, it enters the half-mode substrate integrated waveguide body. It generates strong electromagnetic coupling with the top layer of the meandering line slot and the H-type metal patch. By adjusting the bias voltage of the varactor diode, the equivalent load capacitance of the H-type metal patch is dynamically changed. In addition, the slow wave effect introduced by the meandering line slot is combined to effectively control the phase velocity of the electromagnetic wave in the waveguide, so as to achieve continuous control of the phase of the output signal in a wide frequency band.

[0046] Reference Figure 5 Simulation curves for the reflection coefficient, transmission coefficient, and phase shift range of the phase shifter unit structure are shown. Within a continuous tuning range of 0.35pF to 3.2pF for the varactor diode capacitance, the structure maintains a reflection coefficient better than -10 dB in the 5 GHz to 6 GHz frequency band, with insertion loss fluctuating between 0.8 dB and 4.2 dB. Using the 3.2 pF state as the phase shift reference, a continuous phase shift of approximately 100° is achieved at the 5.5 GHz center frequency.

[0047] Reference Figure 6 This document describes the fabrication of a physical phase shifter and its corresponding testing scheme. The testing setup includes a vector network analyzer, a digital control board, DuPont wires, host computer software, a PC, and SMA connectors. During testing, voltage parameters are set on the host computer. The software packages the control data and transmits it to the digital control board via serial port. The control board then unpacks and verifies the data, driving the DAC to output the corresponding analog voltage signal to the varactor diode. This voltage signal alters the capacitance characteristics of the varactor diode, thereby changing the propagation constant within the integrated waveguide on the half-mode substrate, ultimately achieving continuous modulation of the microwave signal phase. During testing, the vector network analyzer is used to monitor the S-parameters and phase changes under different voltage drives in real time, thus verifying the control performance of the phase shifter unit.

[0048] Reference Figure 7The test results curves show the reflection coefficient, transmission coefficient, and phase shift range of the phase shifter unit structure. Within a continuous tuning range of 0.35 pF to 3.2 pF for the varactor diode, the reflection coefficient of this structure in the 5 GHz to 6 GHz band slightly increased compared to expectations. This is mainly due to the planar curvature of the fabricated component causing incomplete contact of the SMA connector. Additionally, the parasitic effects of the varactor diode and the additional solder introduced at the solder joints also caused local impedance mismatch. Regarding transmission characteristics, the measured insertion loss at the center frequency of 5.5 GHz fluctuated between 0.8 dB and 4.2 dB. During the test, using the 3.2 pF state as the phase shift reference, by continuously adjusting the bias voltage to change the diode capacitance, a continuous linear phase shift of approximately 100° was achieved at the center frequency of 5.5 GHz, indicating that the measured data generally matches the simulation expectations in terms of overall trend.

[0049] Reference Figure 8 This is a schematic diagram of a four-unit cascaded phase shifter. The specific cascading implementation integrates four phase shifters longitudinally on the same dielectric substrate to construct an array structure with greater phase shift capability. To achieve precise integration with the digital beam control system, a binary phase shift control logic is employed. In the specific control strategy, based on the capacitance of the varactor diode, two reference operating states are defined: when a bias voltage is applied to stabilize the junction capacitance of the varactor diode at 2 pF, it is defined as the reference state (state 0); when the bias voltage is adjusted to reduce the capacitance to 0.35 pF, it is defined as the phase-shifted state (state 1). By independently controlling the DC bias ports of the four units, 16 operating modes, ranging from the full reference state (0000) to the full phase-shifted state (1111), can be flexibly combined.

[0050] Reference Figure 9 Simulation curves for the reflection coefficient, transmission coefficient, and phase shift range of the four-unit cascaded phase shifter are shown. This structure exhibits good impedance matching in the 5 GHz to 6 GHz frequency band, with the reflection coefficient generally better than -10 dB in all states. Regarding transmission characteristics, the insertion loss of the cascaded structure remains between 5 dB and 10 dB within the operating frequency band. In terms of phase characteristics, by combining and controlling the bias states of the four units, this structure successfully achieves a continuous 360° phase shift range within the operating frequency band, verifying the achievement of the cascaded design specifications.

[0051] Reference Figure 10 The images show the fabricated prototypes of a four-unit cascaded phase shifter and the corresponding testing scheme. The system uses a digital control board to independently adjust the bias voltage of the four channels to ensure that each phase shifter unit can switch to the reference state or the target phase shift state.

[0052] Reference Figure 11The test results curves for the reflection coefficient, transmission coefficient, and phase shift range of the four-unit cascaded phase shifter are shown. Within the 5 GHz to 5.5 GHz operating frequency band, the cascaded structure exhibits good impedance matching, with the reflection coefficient generally better than -10 dB under most tuning conditions. However, the reflection coefficient increases in the 5.5 GHz to 6 GHz high-frequency band, due to the poor reflection coefficient of the individual units at high frequencies. Regarding transmission and phase characteristics, measured data show that the insertion loss of this structure remains below 20 dB at the center operating frequency of 5.5 GHz. By coordinating the bias voltages of the four units, this structure successfully achieves 360° continuous phase shift coverage within the center frequency and operating bandwidth. The measured results agree well with the simulation results, verifying the achievement of the cascaded design specifications.

[0053] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure, characterized in that, The device includes a dielectric substrate (1), a first metal structure (2) printed on the bottom of the dielectric substrate (1), a second metal structure (3) printed on the top of the dielectric substrate, a metal via structure (4) distributed in the dielectric substrate (1), a 30nH choke inductor (5) soldered to the upper surface of the dielectric substrate, a varactor diode (6) soldered to the upper surface of the dielectric substrate, and a pin header (7) soldered to the dielectric substrate (1); the first metal structure (2) is composed of a grounding structure (8) and a lower grounding line (9); the second metal structure (3) is composed of a microstrip transmission line (10), a meandering line slot (11) etched on the surface of the metal structure, an H-type metal patch (12), and an upper bias line (13); the cascaded phase shifter (14) is composed of four identical phase shifter units connected in series.

2. The half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 1, characterized in that, A varactor diode (6) is connected between an H-type metal patch (12) and a microstrip transmission line (10). A DC bias network consisting of a 30nH choke inductor (5), a lower ground line (9), and an upper bias line (13) is formed. The digital control board adjusts the bias voltage through pin headers (7) to change the capacitance of the varactor diode (6), thereby controlling the phase constant of the transmission line.

3. The half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 1, characterized in that, The dielectric substrate (1) is Rogers RT / duroid 5880, with dimensions of 30mm*65.5mm*0.258mm; The first metal structure (2) at the bottom and the second metal structure (3) at the top of the dielectric substrate are both made of copper with a thickness of 0.035 mm.

4. According to claim 1, a half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure, the metal via structure (4) is a 1*9 array of metal vias, each with a diameter of 0.5mm. The long side of the rectangular substrate is the y-direction, the short side is the x-direction, and the direction perpendicular to the dielectric substrate plane is the z-direction. The metal vias are periodically arranged along the y-direction with a center spacing of 1.52mm, and the number is 9.

5. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The 30nH choke inductor (5) is welded along the x-direction with a welding spacing of 0.46mm.

6. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The varactor diodes (6) are arranged periodically along the y direction with a center spacing of 3.6 mm, and there are 9 of them. They are welded along the x direction with a welding spacing of 0.75 mm.

7. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The pin header (7) is a 2*4 pin header structure, which is welded perpendicularly along the z-direction.

8. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The grounding structure (8) is a rectangular structure with dimensions of 20mm*65.5mm; the lower grounding wire (9) connects the anode of the varactor diode (6) to the grounding terminal of the digital control board.

9. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The microstrip transmission line (10) is 21.5 mm long, with the narrow end of the impedance transformation structure being 1.4 mm wide and the wide end being 2.9 mm wide. The meandering line slots (11) are arranged periodically along the x-direction with a center spacing of 1.6 mm, and there are 5 slots, each with a size of 0.8 mm * 12 mm. The H-shaped metal patches (12) are arranged periodically along the y-direction with a center spacing of 3.6 mm, and there are 9 H-shaped metal patches with an overall size of 2 mm * 3 mm. The four slots etched on them have the same size, each being 0.8 mm * 0.3 mm. The upper bias line (13) connects the cathode of the varactor diode (6) to the power input terminal of the digital control board.

10. A half-mode substrate integrated waveguide phase shifter based on a loaded H-type capacitor structure according to claim 4, characterized in that, The phase shifter units are arranged along the y-direction, and the center-to-center distance between adjacent phase shifter units is 52mm.

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