A millimeter wave filtering power divider based on intermetallic gap waveguide and a working method thereof

Abstract

The application belongs to the technical field of microwave passive devices, and discloses a millimeter wave filtering power divider based on an intermetallic gap waveguide and a working method thereof, which comprises an input port channel, an open resonant ring, a filtering power divider, a metal upper wall and a metal lower wall; the metal upper wall and the metal lower wall are arranged in a stacked manner, the input port channel and the filtering power divider are arranged between the metal upper wall and the metal lower wall; the filtering power divider is of an intermetallic gap waveguide structure, and four resonant cavities are arranged in the intermetallic gap waveguide structure; the input port channel is connected with an input port of the filtering power divider, and the open resonant ring is arranged in the input port channel; the open resonant ring is used for generating a transmission zero point outside a passband of the filtering power divider; the application can greatly reduce the size of the device and electromagnetic loss, can expand the filtering bandwidth, flexibly adjust the resonant frequency, effectively improve the filtering performance and reduce adjacent frequency interference.

Description

Technical Field

[0001] This invention belongs to the field of microwave passive device technology, and specifically relates to a millimeter-wave filter power divider based on a metal gap waveguide and its working method. Background Technology

[0002] With the rapid development of science and technology, communication technology is constantly innovating, gradually evolving from early low-frequency communication to high-frequency, ultra-high-frequency, and even millimeter-wave communication. The demand for communication frequency resources is exploding, leading to increasingly tight communication frequency resources. In order to make more efficient use of limited frequency resources and meet the ever-increasing communication needs, passive devices, as a key component of communication systems, are rapidly developing towards integration, high frequency, and low loss.

[0003] In communication systems, filters and power dividers are two indispensable passive devices. Filters are mainly used to select signals of specific frequencies to achieve signal filtering. Power dividers are used to distribute one input signal to multiple output ports in a certain proportion to achieve signal power distribution. Usually, filters and power dividers are combined in a cascaded manner to meet the comprehensive requirements of communication systems for signal filtering and power distribution.

[0004] However, existing cascading methods tend to significantly increase the overall size of devices and raise electromagnetic losses. Specifically, since each device has its own independent physical structure and packaging, cascading multiple devices in sequence inevitably occupies more space. In addition, signals incur losses when passing through each device, and these losses accumulate after cascading, leading to a significant attenuation of signal strength and affecting communication quality and transmission distance. This loss problem is particularly prominent in the millimeter-wave band, severely restricting the performance improvement of communication systems. Therefore, developing a new type of filter power divider to solve the problems of large size and high electromagnetic losses caused by cascading has become a key issue that urgently needs to be addressed in the current communication field. Summary of the Invention

[0005] To address the technical problems existing in the prior art, this invention provides a millimeter-wave filter power divider based on a metal gap waveguide and its operating method, in order to solve the technical problems that the existing cascade combination method results in a significant increase in the overall size of the device and a significant increase in electromagnetic loss.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a millimeter-wave filter power divider based on a metal gap waveguide, comprising an input port channel, an open resonant ring, a filter power divider, an upper metal wall, and a lower metal wall; The upper metal wall and the lower metal wall are stacked one on top of the other, and the input port channel and the filter power divider are both located between the upper metal wall and the lower metal wall; the filter power divider is a metal gap waveguide structure, and a fourth-order resonant cavity is provided inside the metal gap waveguide structure. The input port channel is connected to the input port of the filter power divider, and the open-ended resonant ring is disposed within the input port channel; wherein, the open-ended resonant ring is used to generate a transmission zero outside the passband of the filter power divider.

[0007] Furthermore, the open-circuit resonator includes a lower frequency open-circuit resonator and a higher frequency open-circuit resonator. The lower-frequency open-circuit resonator and the higher-frequency open-circuit resonator are respectively disposed on both sides of the input port channel; wherein, the distance between the lower-frequency open-circuit resonator and the input port of the filter power divider is greater than the distance between the higher-frequency open-circuit resonator and the input port of the filter power divider.

[0008] Furthermore, both the lower-frequency open-circuit resonator and the higher-frequency open-circuit resonator employ two stacked metal blocks. The lower end of the metal block located below is in contact with the lower metal wall; The height of the upper metal block in the lower frequency open-circuit resonator is less than the height of the upper metal block in the higher frequency open-circuit resonator.

[0009] Furthermore, the power divider is provided with a first-order resonant cavity, a second-order resonant cavity, a third-order resonant cavity, and two fourth-order resonant cavities. The two fourth-order resonant cavities are symmetrically arranged on both sides of the third-order resonant cavity. The first-order resonant cavity, the second-order resonant cavity, the third-order resonant cavity, and the two fourth-order resonant cavities all have square cross-sections, and the cross-sectional sizes are all the same.

[0010] Furthermore, a metal diaphragm is disposed between two adjacent resonant cavity bodies; wherein, the upper end of the metal diaphragm contacts the upper metal wall, and the lower end of the metal diaphragm contacts the lower metal wall.

[0011] Furthermore, a tuning metal pillar is disposed at the center of each resonant cavity; wherein the lower end of the tuning metal pillar is in contact with the lower metal wall.

[0012] Furthermore, it also includes two output port channels, which are respectively located on both sides of the two fourth-order resonant cavities; both the input port channel and the two output port channels adopt standard rectangular waveguides.

[0013] Furthermore, each resonant cavity is formed by enclosing metal pins; wherein, the bottom end of the metal pin is connected to the lower metal wall, and an air gap is pre-set between the top end of the metal pin and the upper metal wall.

[0014] Furthermore, the resonant mode of each resonant cavity is the TE101 mode.

[0015] This invention also provides a method for operating a millimeter-wave filter power divider based on a metal gap waveguide, comprising: The electromagnetic wave emitted by the electromagnetic wave signal source is received through the input port channel, and the received electromagnetic wave is input to the filter power divider; then, the filter power divider is used to filter and distribute the power of the input electromagnetic wave.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The millimeter-wave filter power divider based on a metal gap waveguide provided by this invention integrates filtering and power dividing functions into a metal gap waveguide structure and places it within the space defined by the upper and lower metal walls. This significantly reduces device size and electromagnetic losses, adapting to millimeter-wave characteristics. By setting an open resonant ring in the input port channel, the transmission zero point generated outside the passband can be utilized to expand the filtering bandwidth and flexibly adjust the resonant frequency, effectively improving filtering performance and reducing adjacent-channel interference. Furthermore, the use of a metal gap waveguide structure and the setting of a fourth-order resonant cavity can significantly enhance the filtering effect, improve power distribution characteristics, make the output signal purer and more stable, effectively reduce electromagnetic losses in signal transmission, improve communication quality, and improve the overall performance of the communication system.

[0017] Furthermore, by setting a lower-frequency and a higher-frequency split-ring resonator, high-frequency and low-frequency transmission zeros can be generated, improving the out-of-band rejection performance of the power divider. By adjusting the parameters and positional relationship of the two split-ring resonators, the bandwidth of the filter can be extended, enabling effective filtering of signals over a wider frequency range, thereby optimizing the frequency response characteristics of the filter.

[0018] Furthermore, the split-ring resonator uses two stacked metal blocks, with the upper metal block having a different height for different frequencies, allowing for flexible adjustment of the resonant frequency. By changing the height of the metal blocks, the inductance and capacitance characteristics of the resonant ring can be precisely controlled, achieving precise adjustment of the resonant frequency and improving the versatility and adjustability of the device.

[0019] Furthermore, by placing a metal diaphragm between two adjacent resonant cavity bodies and having the upper and lower ends of the metal diaphragm contact the upper and lower metal walls respectively, it helps to suppress the generation of higher-order modes in the resonant cavity; at the same time, the metal diaphragm can effectively support the upper and lower metal walls. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 An exploded view of a millimeter-wave filter power divider based on a metal gap waveguide, provided for an embodiment. Figure 2 A schematic diagram of the internal structure of a millimeter-wave filter power divider based on a metal gap waveguide provided for an embodiment; Figure 3 This is a three-dimensional structural schematic diagram of the open-loop resonator in the embodiment; Figure 4 This is a three-dimensional structural diagram of the filter power divider in the embodiment; Figure 5 This is a three-dimensional structural diagram of the first and second resonant cavities of the filter power divider in the embodiment; Figure 6 This is a three-dimensional structural diagram of the third and fourth resonant cavities of the filter power divider in the embodiment; Figure 7 The figure shows the simulation results of the scattering parameters of the millimeter-wave filter power divider based on the metal gap waveguide described in the embodiment. Figure 8 The output phase diagram of the millimeter-wave filter power divider based on the metal gap waveguide described in the embodiment is shown.

[0022] Among them, 1 is the input port channel, 2 is the first output port channel, 3 is the second output port channel, 4 is the open resonant ring, 5 is the filter power divider, 6 is the upper metal wall, 7 is the lower metal wall; 41 is the lower frequency open resonant ring, 411 is the first metal block, 412 is the second metal block; 42 is the higher frequency open resonant ring, 421 is the third metal block, 422 is the fourth metal block; 511 is the first-order cavity tuning metal pillar, 512 is the second-order cavity tuning metal pillar, 513 is the third-order cavity tuning metal pillar, 514 is the fourth-order left cavity tuning metal pillar, 515 is the fourth-order right cavity tuning metal pillar; 521 is the metal pin, 522 is the input port metal diaphragm, 523 is the first and second order cavity coupling metal diaphragm, 524 is the second and third order cavity coupling metal diaphragm, 525 is the third and fourth order left cavity coupling metal diaphragm, 526 is the third and fourth order right cavity coupling metal diaphragm, 527 is the left output port metal diaphragm, 528 is the right output port metal diaphragm. Detailed Implementation

[0023] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] This invention provides a millimeter-wave filter power divider based on a metal gap waveguide, comprising an input port channel 1, an open-ended resonant ring 4, a filter power divider 5, an upper metal wall 6, and a lower metal wall 7; the upper metal wall 6 and the lower metal wall 7 are stacked vertically, and the input port channel 1 and the filter power divider 5 are both disposed between the upper metal wall 6 and the lower metal wall 7; the filter power divider 5 is a metal gap waveguide structure, and a fourth-order resonant cavity is disposed inside the metal gap waveguide structure; the input port channel 1 is connected to the input port of the filter power divider 5, and the open-ended resonant ring 4 is disposed within the input port channel 1; wherein, the open-ended resonant ring 4 is used to generate a transmission zero outside the passband of the filter power divider 5.

[0025] The millimeter-wave filter power divider based on a metal gap waveguide described in this invention integrates filtering and power dividing functions within the space defined by the upper and lower metal walls, avoiding the sequential arrangement of multiple independent devices in traditional cascaded methods. This significantly reduces device size and electromagnetic losses, adapting to millimeter-wave band characteristics. Specifically, the metal gap waveguide structure and the inclusion of a fourth-order resonant cavity, combined with an open resonant ring within the input port channel to generate a transmission zero, enhance electromagnetic transmission characteristics, optimize filtering effects, improve out-of-band rejection capability, significantly reduce electromagnetic losses during signal transmission, improve communication quality, and thus effectively enhance the performance of the communication system.

[0026] The following specific embodiments further explain the millimeter-wave filter power divider based on metal gap waveguides provided by the present invention: Example As attached Figure 1-6 As shown, this embodiment provides a millimeter-wave filter power divider based on a metal gap waveguide, including an input port channel 1, a first output port channel 2, a second output port channel 3, an open resonant ring 4, a filter power divider 5, an upper metal wall 6, and a lower metal wall 7.

[0027] The upper metal wall 6 and the lower metal wall 7 are stacked vertically. The input port channel 1, the first output port channel 2, the second output port channel 3, and the filter power divider 5 are all disposed between the upper metal wall 6 and the lower metal wall 7. The filter power divider 5 includes one input port and two output ports. The input port is located at the front end of the filter power divider 5, and the two output ports are located on the left and right sides of the filter power divider 5, respectively. The input port channel 1 is disposed at the front end of the filter power divider 5 and is connected to the input port of the filter power divider 5. The first output port channel 2 is located on the left side of the filter power divider 5 and is connected to one of the output ports of the filter power divider 5. The second output port channel 3 is located on the right side of the filter power divider 5 and is connected to the other output port of the filter power divider 5.

[0028] The slotted resonant ring 4 is disposed within the input port channel 1. The slotted resonant ring 4 is used to generate a transmission zero outside the passband of the power divider 5. Specifically, the slotted resonant ring 4 includes a lower-frequency slotted resonant ring 41 and a higher-frequency slotted resonant ring 42. The lower-frequency slotted resonant ring 41 and the higher-frequency slotted resonant ring 42 are respectively disposed on both sides of the input port channel 1. The lower-frequency slotted resonant ring 41 is used to introduce a transmission zero resonating at a lower frequency, and the higher-frequency slotted resonant ring 42 is used to introduce a transmission zero resonating at a higher frequency, thereby improving the out-of-band rejection performance of the power divider 5. The distance between the lower-frequency slotted resonant ring 41 and the input port of the power divider 5 is greater than the distance between the higher-frequency slotted resonant ring 42 and the input port of the power divider 5.

[0029] Both the lower-frequency open-circuit resonator 41 and the higher-frequency open-circuit resonator 42 employ two stacked metal blocks, with the lower end of the lower metal block contacting the lower metal wall 7. The height of the upper metal block in the lower-frequency open-circuit resonator 41 is less than the height of the upper metal block in the higher-frequency open-circuit resonator 42.

[0030] Specifically, the lower frequency open resonant ring 41 includes a first metal block 411 and a second metal block 412, both of which are cuboid metal blocks. The first metal block 411 and the second metal block 412 are stacked coaxially, with the bottom end of the first metal block 411 in contact with the upper surface of the lower metal wall 7, the top end of the first metal block 411 connected to the bottom end of the second metal block 412, and the top end of the second metal block 412 extending toward the lower surface of the upper metal wall 6.

[0031] Specifically, the higher frequency open-circuit resonant ring 42 includes a third metal block 421 and a fourth metal block 422, both of which are cuboid metal blocks. The third metal block 421 and the fourth metal block 422 are stacked coaxially, with the bottom end of the third metal block 421 in contact with the upper surface of the lower metal wall 7, the top end of the third metal block 421 connected to the bottom end of the fourth metal block 422, and the top end of the fourth metal block 422 extending toward the lower surface of the upper metal wall 6.

[0032] The power divider 5 is a metal gap waveguide structure, and a fourth-order resonant cavity is arranged inside the metal gap waveguide structure. Specifically, the power divider 5 is provided with a first-order resonant cavity, a second-order resonant cavity, a third-order resonant cavity, and two fourth-order resonant cavities. The cross-sections of the first-order resonant cavity, the second-order resonant cavity, the third-order resonant cavity, and the two fourth-order resonant cavities are all square structures, and the cross-sectional sizes are all the same. Preferably, the resonant mode of each resonant cavity is the TE101 mode.

[0033] More specifically, the input terminal of the first-order resonant cavity serves as the input port of the filter power divider 5; the output terminal of the first-order resonant cavity is connected to the input terminal of the second-order resonant cavity; the output terminal of the second-order resonant cavity is connected to the input terminal of the third-order resonant cavity; the two sides of the third-order resonant cavity are respectively set as output terminals; two fourth-order resonant cavities are symmetrically arranged on both sides of the third-order resonant cavity; wherein, the input terminal of the fourth-order resonant cavity located on the left is connected to the left output terminal of the third-order resonant cavity, and the output terminal of the fourth-order resonant cavity located on the left serves as the input port of the filter power divider 5. One of the output ports of the power divider 5 is described; the input terminal of the fourth-order resonant cavity on the right is connected to the right output terminal of the third-order resonant cavity, and the output terminal of the fourth-order resonant cavity on the right serves as the other output port of the power divider 5; the first output port channel 2 is located on the side of the fourth resonant cavity on the left, and the first output port channel 2 is connected to the output terminal of the fourth resonant cavity on the left; the second output port channel 3 is located on the side of the fourth resonant cavity on the right, and the third output port channel 3 is connected to the output terminal of the fourth resonant cavity on the right.

[0034] In the power divider 5, each resonant cavity has a tuning metal pillar at its center; the lower end of the tuning metal pillar contacts the lower metal wall 7; specifically, the tuning metal pillar includes a first-order cavity tuning metal pillar 511, a second-order cavity tuning metal pillar 512, a third-order cavity tuning metal pillar 513, a fourth-order left-side cavity tuning metal pillar 514, and a fourth-order right-side cavity tuning metal pillar 515.

[0035] The first-order cavity tuning metal pillar 511 is located at the center of the first-order resonant cavity, the second-order cavity tuning metal pillar 512 is located at the center of the second-order resonant cavity, the third-order cavity tuning metal pillar 513 is located at the center of the third-order resonant cavity, the fourth-order left-side cavity tuning metal pillar 514 is located at the center of the fourth-order resonant cavity located on the left, and the fourth-order right-side cavity tuning metal pillar 515 is located at the center of the fourth-order resonant cavity located on the right.

[0036] It should be noted that the resonant frequency of the first-order resonant cavity is achieved by adjusting the structural dimensions of the first-order cavity tuning metal pillar 511; the resonant frequency of the second-order resonant cavity is achieved by adjusting the structural dimensions of the second-order cavity tuning metal pillar 512; the resonant frequency of the third-order resonant cavity is achieved by adjusting the structural dimensions of the third-order cavity tuning metal pillar 513; the resonant frequency of the fourth-order resonant cavity located on the left is achieved by adjusting the structural dimensions of the fourth-order left-side cavity tuning metal pillar 514; and the resonant frequency of the fourth-order resonant cavity located on the right is achieved by adjusting the structural dimensions of the fourth-order right-side cavity tuning metal pillar 515.

[0037] In the power divider 5, each resonant cavity is formed by metal pins 521, that is, each resonant cavity is a slot gap waveguide resonant cavity composed of metal pins 521 with the same shape and size; wherein, the bottom end of the metal pin 521 is connected to the lower metal wall, and an air gap is preset between the top end of the metal pin 521 and the upper metal wall.

[0038] In the power divider 5, a metal diaphragm is disposed between two adjacent resonant cavities. The upper end of the metal diaphragm contacts the upper metal wall 6, and the lower end of the metal diaphragm contacts the lower metal wall 7. Specifically, the metal diaphragm 5 includes an input port metal diaphragm 522, a first- or second-order cavity coupling metal diaphragm 523, a second- or third-order cavity coupling metal diaphragm 524, a third- or fourth-order left-side cavity coupling metal diaphragm 525, a third- or fourth-order right-side cavity coupling metal diaphragm 526, a left-side output port metal diaphragm 527, and a right-side output port metal diaphragm 528.

[0039] The input port metal diaphragms 522 are symmetrically arranged on both sides of the input end of the first-order resonant cavity; the first- and second-order cavity coupling metal diaphragms 523 are symmetrically arranged between the output end of the first-order resonant cavity and the input end of the second-order resonant cavity; the second- and third-order cavity coupling metal diaphragms 524 are symmetrically arranged between the output end of the second-order resonant cavity and the input end of the third-order resonant cavity; the third- and fourth-order left-side cavity coupling metal diaphragms 525 are symmetrically arranged between the left-side output end of the third-order resonant cavity and the input end of the fourth-order resonant cavity located on the left; the third- and fourth-order right-side cavity coupling metal diaphragms 526 are symmetrically arranged between the right-side output end of the third-order resonant cavity and the input end of the fourth-order resonant cavity located on the right; the left-side output port metal diaphragms 527 are symmetrically arranged on both sides of the output end of the fourth-order resonant cavity located on the left; and the right-side output port metal diaphragms 528 are symmetrically arranged on both sides of the output end of the fourth-order resonant cavity located on the right.

[0040] It should be noted that the external quality factor of the input port of the power divider 5 is achieved by adjusting the slot width of the metal diaphragm 522 at the input port, and the external quality factor of the output port of the power divider 5 is achieved by adjusting the slot width of the metal diaphragm 527 at the left output port or the metal diaphragm 528 at the right output port; the coupling coefficient between the first-order resonant cavity and the second-order resonant cavity is achieved by adjusting the slot width of the coupling metal diaphragm 523 between the first and second-order cavities; the coupling coefficient between the second-order resonant cavity and the third-order resonant cavity is achieved by adjusting the slot width of the coupling metal diaphragm 524 between the second and third-order cavities; and the coupling coefficient between the third-order resonant cavity and the fourth-order resonant cavity is achieved by adjusting the slot width of the coupling metal diaphragm 525 between the left and right sides of the third and fourth-order cavities or the coupling metal diaphragm 526 between the third and fourth-order cavities.

[0041] Working principle and working method: The working method of the millimeter-wave filter power divider based on the metal gap waveguide described in this embodiment is as follows: The electromagnetic wave emitted by the electromagnetic wave signal source is received through input port channel 1, and the received electromagnetic wave is input to the filter power divider 5; then, the filter power divider 5 is used to filter and distribute the power of the input electromagnetic wave.

[0042] Specifically, the electromagnetic wave emitted by the electromagnetic wave signal source is received through input port channel 1. After passing through the open resonant ring 4 in input port channel 1, the electromagnetic wave is input to the filter power divider 5 for filtering and power distribution. In the filter power divider 5, the electromagnetic wave passes through the first-order resonant cavity, the second-order resonant cavity, and the third-order resonant cavity in sequence, and then through the fourth-order resonant cavity located on the left or the fourth-order resonant cavity located on the right. Afterward, the filtered and power-distributed electromagnetic wave is output through the first output port channel 2 or the second output port channel 3, realizing the filtering and power distribution function.

[0043] The millimeter-wave filter power divider based on a metal gap waveguide described in this embodiment achieves both filtering and power division functions by introducing a filter power divider with a metal gap waveguide. This not only significantly reduces lateral electromagnetic radiation and exhibits low loss characteristics, but also achieves high performance without requiring complete metal electrical contact, significantly reducing the fabrication difficulty and cost of passive devices based on gap waveguides. Furthermore, by adding an all-metal split-ring resonator to the input port channel, a transmission zero is introduced using the split-ring resonator, achieving the fusion of filtering and power division functions while also possessing the characteristics of low fabrication difficulty, low insertion loss, and high out-of-band rejection. In particular, the fusion of the all-metal split-ring resonator with the filter power divider allows the all-metal split-ring resonator to generate a transmission zero outside the filter power divider's band, which can significantly improve the out-of-band rejection performance of the filter power divider.

[0044] Size characteristics description: The millimeter-wave filter power divider based on a metal gap waveguide described in this embodiment has an overall external shape of a cube with a side length of 28mm. The length of the first input port channel 1 is 5.4mm, the length of the second output port channel 2 is 8.6mm, and the length of the second output port channel 3 is 8.6mm. The input port channel 1, the first output port channel 2, and the second output port channel 3 all adopt standard rectangular waveguides. Preferably, a WR-15 type waveguide port is used. The width of the WR-15 type waveguide port is 3.76mm, and the height is 1.88mm.

[0045] In the lower frequency open resonant ring 41, the first metal block 411 has dimensions of length × width × height = 0.3 × 0.3 × 0.2 mm, a distance of 4.78 mm from the input port metal diaphragm 522, and a distance of 0.06 mm from the right side wall of the input port channel; the second metal block 412 has dimensions of length × width × height = 0.5 × 0.3 × 0.79 mm, a distance of 4.78 mm from the input port metal diaphragm 522, and a distance of 0.06 mm from the right side wall of the input port channel.

[0046] In the higher frequency open resonant ring 42, the third metal block 421 has dimensions of length × width × height = 0.3 × 0.3 × 0.2 mm, a distance of 3.77 mm from the input port metal diaphragm 522, and a distance of 0.25 mm from the right side wall of the input port channel; the second metal block 412 has dimensions of length × width × height = 0.5 × 0.3 × 0.8 mm, a distance of 3.77 mm from the input port metal diaphragm 522, and a distance of 0.25 mm from the right side wall of the input port channel.

[0047] In each resonant cavity, three rows of metal pins 521 are arranged on each side. The metal pins 521 are attached to the lower metal wall 7 to prevent electromagnetic wave leakage. The width of the metal pins 521 is the same as the width of the metal diaphragm 522 at the input port, the metal diaphragm 523 for the first and second order cavities, the metal diaphragm 524 for the second and third order cavities, the metal diaphragm 525 for the third and fourth order left cavity, the metal diaphragm 526 for the third and fourth order right cavity, the metal diaphragm 527 for the left output port, or the metal diaphragm 528 for the right output port. The dimensions of the metal pins 521 are length × width × height = 0.4 × 0.4 × 1.4 mm, and the spacing period of the metal pins 521 is 0.8 mm. The dimensions of the cross-section of each resonant cavity are length × width = 2.8 × 2.8 mm.

[0048] The slot width of the input port metal diaphragm 522 is 4.01 mm, the slot width of the first and second order cavity coupling metal diaphragm 523 is 1.62 mm, the slot width of the second and third order cavity coupling metal diaphragm 524 is 1.38 mm, the slot width of the third and fourth order left cavity coupling metal diaphragm 525 is 1.54 mm, the slot width of the third and fourth order right cavity coupling metal diaphragm 526 is 1.54 mm, the slot width of the left output port metal diaphragm 527 is 2.61 mm, and the slot width of the right output port metal diaphragm 528 is 2.61 mm.

[0049] The dimensions of the first-order cavity tuning metal pillar 511 are radius × height = 0.15 × 0.58 mm; the dimensions of the second-order cavity tuning metal pillar 512 are radius × height = 0.19 × 0.66 mm; the dimensions of the third-order cavity tuning metal pillar 513 are radius × height = 0.12 × 0.65 mm; the dimensions of the fourth-order left-side cavity tuning metal pillar 514 are radius × height = 0.13 × 0.61 mm; and the dimensions of the fourth-order right-side cavity tuning metal pillar 515 are radius × height = 0.13 × 0.61 mm.

[0050] As attached Figure 7 As shown, attached Figure 7The figure shows the simulation results of the scattering parameters of the millimeter-wave filter power divider based on the metal gap waveguide described in the embodiment; from the appendix Figure 7 As can be seen, in the millimeter-wave power divider based on the metal gap waveguide, by introducing a lower-frequency slotted resonant ring and a higher-frequency slotted resonant ring, the lower-frequency slotted resonant ring and the higher-frequency slotted resonant ring resonate outside the passband of the power divider, forming two transmission zeros outside the passband. The frequencies of the two transmission zeros are 58 GHz and 62.032 GHz, respectively. The return loss of the power divider is better than 17 dB. The power divider has equal power distribution, a center frequency of 60 GHz, and an insertion loss better than 0.6 dB. The form factor of the power divider at 30 dB is 1.53, which shows good out-of-band rejection performance.

[0051] As attached Figure 8 As shown, attached Figure 8 The output phase diagram of the millimeter-wave filter power divider based on the metal gap waveguide described in the embodiment is given in the appendix; Figure 8 As can be seen from the data, both output channels of the filter power divider are in-phase outputs, and each channel is an in-phase power divider.

[0052] The millimeter-wave power divider based on a metal gap waveguide described in this invention has a cubic external shape. The cubic structure contains an input port channel, a first output port channel, a second output port, and the power divider itself. An open-ended resonant ring is disposed within the input port channel. The two open-ended resonant rings in the input port channel are identical in all parameters except for their distance from the metal diaphragm at the input port and the height of the metal block not in contact with the lower metal wall. These two open-ended resonant rings generate transmission zeros outside the power divider's band, improving its out-of-band rejection performance. The entire structure is all-metal, facilitating fabrication and exhibiting high power capacity and low insertion loss. A gap waveguide structure is adopted. To prevent electromagnetic wave leakage, the gap waveguide is set up with three rows of metal pins. The resonant cavity is constructed using metal pins of the same size and shape. The power divider is a fourth-order cavity structure. The fourth-order resonant cavity is set up with two identical resonant cavities on the left and right sides to achieve filtering and equal power distribution functions. In order to suppress higher-order modes, the metal diaphragm between adjacent resonant cavities is in contact with both the upper and lower metal walls. At the same time, the metal diaphragm that is in complete contact with the upper and lower metal walls can also provide a certain degree of support. All resonant cavities in the power divider are the same size. The resonant frequency can be adjusted by metal tuning pins to fix the size of the power divider cavity and reduce the manufacturing difficulty.

[0053] In this invention, two open-ended resonant rings are arranged in the input port channel, followed by a filter power divider. The open-ended resonant rings are all-metal structures and connected to a lower metal wall. The filter power divider is a metal gap waveguide structure with an internal gap waveguide cavity. The internal cavity of the metal gap waveguide structure is configured as a fourth-order cavity, wherein the fourth-order resonant cavity is configured as two symmetrical cavities. The resonant cavities are coupled through a metal diaphragm. The internal cavity of the filter power divider has a square cross-section and is the same size. A tuning metal pillar is arranged inside the cavity. This invention achieves the functional integration of a traditional filter and a power divider, adopts an all-metal structure to improve power capacity, uses a metal gap waveguide structure to reduce manufacturing difficulty and cost, and uses open-ended resonant rings to introduce two transmission zeros operating out of band. In addition, this invention also has low insertion loss and good out-of-band rejection performance.

[0054] The millimeter-wave filter power divider described in this invention can be machined and the air gaps present during the machining process can be eliminated by soldering. In addition, the filter power divider is designed using gap waveguides. An air gap is preset between the top of the metal pin and the upper metal wall. The propagation of electromagnetic waves of a specific frequency is blocked by adjusting the height of the air gap. The machining of the gap waveguide does not require complete electrical contact, which reduces the difficulty of device manufacturing. Except for the metal diaphragm coupling between the resonant cavities, the rest of the structure uses gap waveguides, which do not require complete electrical contact, thereby reducing the losses caused by errors in machining and assembly.

[0055] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

Claims

1. A millimeter-wave filter power divider based on a metal gap waveguide, characterized in that, It includes an input port channel (1), an open resonant ring (4), a filter power divider (5), an upper metal wall (6), and a lower metal wall (7). The upper metal wall (6) and the lower metal wall (7) are stacked one on top of the other. The input port channel (1) and the filter power divider (5) are both located between the upper metal wall (6) and the lower metal wall (7). The filter power divider (5) is a metal gap waveguide structure, and a fourth-order resonant cavity is provided inside the metal gap waveguide structure. The input port channel (1) is connected to the input port of the filter power divider (5), and the open resonant ring (4) is disposed in the input port channel (1); wherein, the open resonant ring (4) is used to generate a transmission zero outside the passband of the filter power divider (5); The open-loop resonator (4) includes a lower frequency open-loop resonator (41) and a higher frequency open-loop resonator (42). The lower frequency open-ring resonator (41) and the higher frequency open-ring resonator (42) are respectively disposed on both sides of the input port channel (1); wherein, the distance between the lower frequency open-ring resonator (41) and the input port of the filter power divider (5) is greater than the distance between the higher frequency open-ring resonator (42) and the input port of the filter power divider (5). Both the lower frequency open-circuit resonator (41) and the higher frequency open-circuit resonator (42) are made of two stacked metal blocks. The lower end of the metal block located below is in contact with the lower metal wall (7); The height of the upper metal block in the lower frequency open resonant ring (41) is less than the height of the upper metal block in the higher frequency open resonant ring (42).

2. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 1, characterized in that, The filter power divider (5) is provided with a first-order resonant cavity, a second-order resonant cavity, a third-order resonant cavity and two fourth-order resonant cavities; The two fourth-order resonant cavities are symmetrically arranged on both sides of the third-order resonant cavity. The first-order resonant cavity, the second-order resonant cavity, the third-order resonant cavity, and the two fourth-order resonant cavities all have square cross-sections, and the cross-sectional sizes are all the same.

3. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 1, characterized in that, A metal diaphragm is disposed between two adjacent resonant cavities; wherein, the upper end of the metal diaphragm is in contact with the upper metal wall (6), and the lower end of the metal diaphragm is in contact with the lower metal wall (7).

4. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 1, characterized in that, Each resonant cavity has a tuning metal pillar at its center; wherein the lower end of the tuning metal pillar is in contact with the lower metal wall (7).

5. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 1, characterized in that, It also includes two output port channels, which are respectively located on both sides of the two fourth-order resonant cavities; the input port channel (1) and the two output port channels are both standard rectangular waveguides.

6. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 5, characterized in that, Each resonant cavity is formed by metal pins (521); wherein, the bottom end of the metal pins (521) is connected to the lower metal wall (7), and an air gap is preset between the top end of the metal pins (521) and the upper metal wall (6).

7. A millimeter-wave filter power divider based on a metal gap waveguide according to claim 1, characterized in that, The resonant mode of each resonant cavity is TE101 mode.

8. A method for operating a millimeter-wave filter power divider based on a metallic gap waveguide as described in any one of claims 1-7, comprising: The electromagnetic wave emitted by the electromagnetic wave signal source is received by the input port channel (1), and the received electromagnetic wave is input to the filter power divider (5); then, the input electromagnetic wave is filtered and the power is distributed by the filter power divider (5).

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