Resonance unit, filter and base station

Abstract

The invention provides a resonance unit, a filter and a base station, the resonance unit comprises a dielectric block, the dielectric block is provided with a top surface and a bottom surface which are oppositely arranged in a first direction, and a side surface connected between the top surface and the bottom surface, the dielectric block is provided with a resonance groove, and the resonance groove is recessed inwards from the top surface or the bottom surface of the dielectric block. The groove bottom surface and the groove wall surface of the resonance groove are covered with an electromagnetic shielding layer. The resonance groove comprises a first part and a second part, a dielectric resonance structure is formed in the area, located on the groove bottom face of the first part and around the second part, in the dielectric block, the dielectric resonance structure is in a U shape or an L shape in the plane perpendicular to the third direction, and the resonance frequency of the dielectric resonance structure is related to the length of the dielectric resonance structure. According to the resonance unit provided by the embodiment of the invention, decoupling between resonance units which are relatively close in the filter and miniaturization of the size of the filter can be considered.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to a resonance unit, a filter, and a base station. Background Art

[0002] In the field of wireless communications, using materials with high dielectric constants to make filters can reduce the size of the filters. However, at the same time, the smaller size will cause the resonant units inside the filter to be closer to each other, resulting in a large amount of redundant parasitic coupling, making filter design optimization and debugging more difficult. How to achieve decoupling between adjacent resonant units while reducing the filter size has become a major challenge in filter design.

[0003] Existing solutions create an isolation structure by leaving a certain gap between two closely spaced resonant units. This approach results in a less compact filter structure and increases filter size. Some products use holes in the dielectric block to create an isolation structure, but this also reduces the compactness of the filter structure. Therefore, existing filters struggle to reconcile decoupling between closely spaced resonant units with miniaturization. Summary of the Invention

[0004] The resonance unit, filter, and base station provided in the embodiments of the present application solve the problem in existing filters of the incompatibility between decoupling of closely spaced resonance units and miniaturization of the filter size.

[0005] An embodiment of the present application provides a resonance unit, which includes a dielectric block having a top surface and a bottom surface arranged opposite to each other in a first direction, and a side surface connected between the top surface and the bottom surface. The dielectric block is provided with a resonance groove, which is recessed inward from the top surface or the bottom surface of the dielectric block along the first direction, and the bottom surface and the wall surface of the resonance groove are covered with an electromagnetic shielding layer.

[0006] The resonant slot includes a first portion and a second portion connected sequentially in a first direction. The first portion extends through the dielectric block in the second direction, and the slot opening of the first portion constitutes the slot opening of the resonant slot. The slot bottom surface of the second portion constitutes the slot bottom surface of the resonant slot, and the slot opening of the second portion is connected to the slot bottom surface of the first portion. A dielectric resonant structure is formed in the dielectric block around the slot bottom surface of the first portion and the second portion. The dielectric resonant structure is U-shaped or L-shaped in a plane perpendicular to a third direction, and the resonant frequency of the dielectric resonant structure is related to the length of the dielectric resonant structure. The first direction, the second direction, and the third direction are mutually perpendicular.

[0007] The resonant unit provided in the embodiment of the present application has a resonant slot provided in the dielectric block, and the shape of the resonant slot is designed so that the area around the resonant slot forms a dielectric resonant structure with a U-shaped or L-shaped cross-section. On the one hand, the dielectric resonant structure can excite a resonant mode (the electric field around the resonant slot is distributed in the dielectric resonant structure), so that the resonant unit can work normally in the filter. In addition, the resonant frequency of the dielectric resonant structure is related to its length, and the operating frequency of the resonant unit can be adjusted by changing the length of the dielectric resonant structure. On the other hand, the resonant slot itself can be used as an isolation slot, and the electromagnetic shielding layer covering the bottom surface and the wall surface of the resonant slot can serve as a partition wall to shield the electromagnetic signal. There is no need to add gaps, isolation slots, holes and other structures in the filter. Only by arranging and laying out the resonant units in the filter, signal coupling and signal decoupling between different resonant units (including decoupling between resonant units that are close to each other) can be achieved simultaneously, which is conducive to improving the compactness of the filter structure and reducing the size of the filter.

[0008] It can be seen that the resonance unit provided in the embodiment of the present application can take into account both the decoupling between the resonance units that are relatively close in the filter and the miniaturization of the filter size.

[0009] In some embodiments, the bottom surface and the wall surface of the resonance groove are both flat, which facilitates processing.

[0010] In some embodiments, two sidewall surfaces of the resonance slot that are opposite to each other in the third direction are both configured as planes perpendicular to the third direction.

[0011] In some embodiments, two sidewall surfaces of the second portion of the resonance slot that are opposite to each other in the second direction are both configured as planes perpendicular to the second direction.

[0012] In some embodiments, in a plane perpendicular to the third direction, widths of various portions of the dielectric resonant structure along its extension direction are the same.

[0013] In some embodiments, the total length of the dielectric resonant structure is L0, the resonant frequency of the dielectric resonant structure is f0, and L0 is The difference is within the preset threshold range, where c is the speed of light in vacuum, ε r is the relative dielectric constant of the dielectric block.

[0014] When the above conditions are met, other structures and sizes in the resonance unit can be flexibly changed, so that the resonance unit is not restricted to a single form, and the shape and structure are more flexible and changeable, and suitable for more filters.

[0015] An embodiment of the present application further provides a filter, comprising a plurality of resonance units, at least one of the plurality of resonance units being a resonance unit provided by any of the foregoing embodiments.

[0016] The filter provided in the embodiment of the present application can achieve decoupling between resonant units that are close to each other while being miniaturized.

[0017] In some embodiments, the plurality of resonant units include five resonant units arranged sequentially along a fourth direction, namely, a first resonant unit, a second resonant unit, a third resonant unit, a fourth resonant unit, and a fifth resonant unit. Each of the five resonant units is a resonant unit provided in any of the aforementioned embodiments. The third direction of each resonant unit is parallel to the fourth direction, and the notch of the resonant slot of the third resonant unit is oriented oppositely to the notches of the resonant slots of the other resonant units.

[0018] With the above solution, the resonant slot of the third resonant unit is located between the dielectric resonant structure of the second resonant unit and the dielectric resonant structure of the fourth resonant unit. The electromagnetic shielding layer covering the inner surface of the resonant slot of the third resonant unit acts as a partition wall, shielding the signal transmission between the second and fourth resonant units. The resonant slot of the second resonant unit is located between the dielectric resonant structure of the first resonant unit and the dielectric resonant structure of the third resonant unit, shielding the signal transmission between the two. The resonant slot of the fourth resonant unit is located between the dielectric resonant structure of the third resonant unit and the dielectric resonant structure of the fifth resonant unit, shielding the signal transmission between the two.

[0019] In some embodiments, the plurality of resonant units include five resonant units arranged sequentially along a fourth direction, namely a first resonant unit, a second resonant unit, a third resonant unit, a fourth resonant unit, and a fifth resonant unit. Each of the first resonant unit, the third resonant unit, and the fifth resonant unit adopts the resonant unit provided in any of the foregoing embodiments, and the third direction of each of the first resonant unit, the third resonant unit, and the fifth resonant unit is parallel to the fourth direction, and the notch orientation of the resonant slot of the first resonant unit is opposite to the notch orientation of the resonant slot of the third resonant unit and the notch orientation of the resonant slot of the fifth resonant unit.

[0020] Each of the second and fourth resonance units includes a dielectric block, which is provided with a columnar resonance groove. The columnar resonance groove is recessed inward along the fifth direction from a side surface of the dielectric block in the fifth direction, and the inner surface of the columnar resonance groove is covered with an electromagnetic shielding layer. The columnar resonance groove of the second resonance unit and the columnar resonance groove of the fourth resonance unit have the same groove opening direction, and are both perpendicular to the groove opening direction of the resonance groove of the first resonance unit and the groove opening direction of the resonance groove of the third resonance unit.

[0021] With the above structure, the first resonant unit, the second resonant unit, and the third resonant unit together constitute a cross-coupling module. The notches of the resonant slots of the first resonant unit and the third resonant unit face opposite directions, and the cross-coupling between them is capacitive (negative) coupling, which generates a transmission zero at the low-frequency end of the filter's operating passband, thereby improving the suppression of low-frequency signals. The third resonant unit, the fourth resonant unit, and the fifth resonant unit together constitute a cross-coupling module. The notches of the resonant slots of the third resonant unit and the fifth resonant unit face the same direction, and the cross-coupling between them is inductive (positive) coupling, which generates a transmission zero at the high-frequency end of the filter's operating passband, thereby improving the suppression of high-frequency signals.

[0022] In some embodiments, the plurality of resonant units include five resonant units arranged sequentially along the fourth direction, namely, a first resonant unit, a second resonant unit, a third resonant unit, a fourth resonant unit, and a fifth resonant unit. The first resonant unit and the third resonant unit are resonant units provided in any of the foregoing embodiments, and the third direction of each of the first resonant unit and the third resonant unit is parallel to the fourth direction, and the notch opening of the resonant slot of the first resonant unit is oriented oppositely to the notch opening of the resonant slot of the third resonant unit.

[0023] Each of the second resonant unit, the fourth resonant unit, and the fifth resonant unit includes a dielectric block, which is provided with a columnar resonant slot, which is recessed inwardly along the fifth direction from a side surface of the dielectric block in the fifth direction, and the inner surface of the columnar resonant slot is covered with an electromagnetic shielding layer; the slot opening direction of the columnar resonant slot of the fifth resonant unit is the same as the slot opening direction of the resonant slot of the third resonant unit, the slot opening direction of the columnar resonant slot of the second resonant unit is the same as the opening direction of the columnar resonant slot of the fourth resonant unit, and both are perpendicular to the slot opening direction of the columnar resonant slot of the fifth resonant unit.

[0024] In some embodiments, the fourth direction is a linear direction. The filter structure in which the resonant units are arranged in a straight line is simple, the main transmission path is a straight line, and the energy coupling between different resonant units is easy to control and debug.

[0025] In some embodiments, the dielectric blocks of the multiple resonant units are configured as an integrated dielectric block, the outer surface of which is covered with an electromagnetic shielding layer. All resonant units in the filter are designed as an integrated structure and can be directly processed and formed on a single structural block.

[0026] The present application also provides a base station including the filter provided by any of the above embodiments. The filter can achieve decoupling between closely spaced resonant units while being miniaturized. Application of the filter in a base station can better filter signal clutter and reduce the space occupied by the filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram of a dielectric filter unit in the prior art;

[0028] Figure 2 It is a structural diagram of a filter in the prior art;

[0029] Figure 3 for Figure 2 Schematic diagram of the topology of the filter;

[0030] Figure 4 This is a schematic diagram of the three-dimensional structure of the first embodiment of the resonance unit of the present application;

[0031] Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure in the AA direction;

[0032] Figure 6 Schematic diagram of the positional relationship between the dielectric resonant structure and the resonant slot in the resonant unit of the embodiment of the present application;

[0033] Figure 7 Schematic diagram of the cross-sectional structure of the second embodiment of the resonance unit of the present application;

[0034] Figure 8 Schematic diagram of the cross-sectional structure of the third embodiment of the resonance unit of the present application;

[0035] Figure 9 This is a diagram of an electric field simulation test of a resonant unit according to an embodiment of the present application;

[0036] Figure 10 Schematic diagram of the cross-sectional structure of a fourth embodiment of the resonance unit of the present application;

[0037] Figure 11a A side view of a first embodiment of a resonance unit according to an embodiment of the present application;

[0038] Figure 11b A side view of a fifth embodiment of the resonance unit according to an embodiment of the present application;

[0039] Figure 12 This is a schematic diagram of the three-dimensional structure of the first embodiment of the filter of the present application;

[0040] Figure 13 for Figure 12 Schematic diagram of the topology of the filter;

[0041] Figure 14 This is a schematic diagram of the three-dimensional structure of the second embodiment of the filter of the embodiment of the present application;

[0042] Figure 15Schematic diagram of the three-dimensional structure of the third embodiment of the filter of the present application;

[0043] Figure 16 for Figure 15 Schematic diagram of the topology of the filter;

[0044] Figure 17 Schematic diagram of the three-dimensional structure of the second resonance unit in the third embodiment of the filter of the embodiment of the present application;

[0045] Figure 18 Schematic diagram of the three-dimensional structure of the fourth embodiment of the filter of the present application;

[0046] Figure 19 This is a schematic diagram of the system structure of the base station in an embodiment of the present application.

[0047] Description of reference numerals:

[0048] Existing technology:

[0049] 1', dielectric filter unit; 11', dielectric block;

[0050] 100', first dielectric resonant cavity; 200', second dielectric resonant cavity;

[0051] 110', first frequency hole; 210', second frequency hole; 300', coupling slot; 400', third frequency hole;

[0052] 2', filter; 500', isolation hole; 600', isolation hole.

[0053] This application:

[0054] 100, resonance unit;

[0055] 1. dielectric block; 11. top surface; 12. bottom surface;

[0056] 131, first side; 132, second side; 133, third side; 134, fourth side;

[0057] 2. Resonant slot; 21. Slot opening; 22. Slot bottom; 23. Slot wall; 231. Side wall;

[0058] 24, first part; 241, notch; 242, bottom surface of the groove;

[0059] 25. Second part; 251. Notch; 252. Groove bottom; 253. Side wall

[0060] 3. Electromagnetic shielding layer; 4. Dielectric resonant structure; 41. Bottom; 42. Connecting arm;

[0061] 200, filter; 51, first resonance unit; 52, second resonance unit; 53, third resonance unit;

[0062] 54. Fourth resonance unit; 55. Fifth resonance unit;

[0063] 6. Dielectric block; 61. Columnar resonant slot; 62. Electromagnetic shielding layer;

[0064] 71. Electromagnetic shielding layer; 72. Input end; 73. Output end;

[0065] 300, base station;

[0066] 81. Antenna; 82. Indoor baseband processing unit;

[0067] 821. Digital system; 822. RF transceiver system; 8221. Filter; 823. Filter;

[0068] 83. Remote radio frequency module; 84. Power amplifier; 85. Low noise amplifier;

[0069] z, first direction; x, second direction; y, third direction; s, fourth direction; d, fifth direction. DETAILED DESCRIPTION

[0070] The following specific embodiments illustrate the implementation of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with some embodiments, this does not mean that the features of this application are limited to the implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide an in-depth understanding of the present application, the following description will contain many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other unless there is a conflict.

[0071] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0072] The following explains the terms that may appear in the embodiments of the present application.

[0073] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0074] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0075] Coupling: used to describe the size of the signal or energy interaction ability between resonators inside the filter. Coupling can be divided into magnetic coupling and electric coupling according to polarity. Magnetic coupling is mainly achieved through magnetic fields or currents, while electric coupling is mainly achieved through electric fields. Direct coupling can also be called "electrical connection", which is understood as physical contact and electrical conduction between components; it can also be understood as a form of connection between different components in the circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals; "indirect coupling" can be understood as two conductors being electrically conductive in an airless / non-contact manner. In one embodiment, indirect coupling can also be called capacitive coupling, for example, signal transmission is achieved by coupling between the gap between two conductive parts to form an equivalent capacitor.

[0076] Relative arrangement: can be understood as being arranged face to face (opposite to, or face to face) or being arranged with at least a portion of the area overlapping along a certain direction.

[0077] Dielectric constant: the main parameter reflecting the dielectric properties or polarization properties of the dielectric under the action of electrostatic field.

[0078] Relative permittivity: A physical parameter that characterizes the dielectric or polarization properties of a dielectric material. Its value is equal to the ratio of the capacitance of a capacitor of the same size made with the dielectric material to that made with a vacuum dielectric. This value also characterizes the material's ability to store electricity. It is also called relative permittivity.

[0079] The limitations of parallelism, perpendicularity, and identity (e.g., same length, same width, etc.) mentioned in the embodiments of this application are based on current state-of-the-art technology and are not strictly mathematical definitions. Parallel or perpendicular radiators can have a deviation within a predetermined angular range. In one embodiment, the predetermined angle is 10°, and the deviation can be within a range of ±5°, for example.

[0080] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0081] In the field of wireless communications, using materials with high dielectric constants to make filters can reduce the size of the filters. However, at the same time, the smaller size will cause the resonant units inside the filter to be closer to each other, resulting in a large amount of redundant parasitic coupling, making filter design optimization and debugging more difficult. How to achieve decoupling between adjacent resonant units while reducing the filter size has become a major challenge in filter design.

[0082] Generally, a filter contains multiple resonant units. The interaction between the resonant units can form a signal passband, so that signals with frequencies within the passband range can pass through the filter smoothly, while signals outside the passband range will be filtered out. This is the basic working principle of the filter.

[0083] In the design of the filter, a main transmission path is usually formed among multiple resonant units. After the signal enters the filter from the input end, it is transmitted along the main transmission path to the output end. Energy coupling is required between adjacent resonant units connected in series by the main transmission path. In addition, some optimization designs can also be performed. For example, in some scenarios, in order to improve the out-of-band suppression of the filter (the suppression of signals outside the passband), a resonant unit is added between the two mutually coupled resonant units, that is, a transmission path is added. The three resonant units are coupled to form a cross-coupling module, also known as a CT tripole structure, which generates a transmission zero point outside the passband, which can better suppress signals outside the passband. For other resonant units that are close and do not require energy coupling, an isolation structure must be set between them. If the isolation structure is not set or the effect of the isolation structure does not meet expectations, unnecessary parasitic coupling will be generated, causing the response curve of the filter to be distorted and the transmission loss to increase. It will also generate additional transmission zeros, which will increase the difficulty of debugging and optimizing the filter. Traditional isolation methods create an isolation structure by leaving a gap between two closely spaced resonant units. This approach results in a less compact filter structure and increases filter size. Some products employ a method of perforating dielectric blocks to create an isolation structure. The following details the implementation of this method, along with accompanying figures.

[0084] See also Figure 1-Figure 3 , Figure 1 It is a structural diagram of a dielectric filter unit in the prior art; Figure 2 It is a structural diagram of a filter in the prior art; Figure 3 for Figure 2 Schematic diagram of the filter topology.

[0085] like Figure 1 As shown, the dielectric filter unit 1' includes a dielectric block 11', in which a first dielectric resonant cavity 100' and a second dielectric resonant cavity 200' are formed. The end surface of the first dielectric resonant cavity 100' is recessed inward to form a first frequency hole 110', and the end surface of the second dielectric resonant cavity 200' is recessed inward to form a second frequency hole 210'. The first frequency hole 110' and the second frequency hole 210' are used to generate and tune the frequency of the resonant cavity. The first dielectric resonant cavity 100' and the second dielectric resonant cavity 200' are both the resonant units mentioned above, or it can be understood that the dielectric filter unit 1' includes two resonant units.

[0086] Because a signal-permeable medium exists between the first frequency aperture 110' and the second frequency aperture 210', signals can be transmitted and coupled between them. Furthermore, a coupling slot 300' is provided at the connection between the first dielectric resonant cavity 100' and the second dielectric resonant cavity 200'. By adjusting the size of the coupling slot 300', the size of the medium between the first frequency aperture 110' and the second frequency aperture 210' can be changed, thereby adjusting the coupling strength between the two frequency apertures. A third frequency aperture 400' is also provided at the connection between the first dielectric resonant cavity 100' and the second dielectric resonant cavity 200'. The third frequency aperture 400' is coupled to the first frequency aperture 110' and the second frequency aperture 210', respectively. Together, the first frequency aperture 110', the second frequency aperture 210', and the third frequency aperture 400' form a cross-coupling module, generating a transmission zero outside the passband and improving the filter's out-of-band suppression.

[0087] like Figure 2 As shown, two dielectric filter units 1' can be spliced ​​together to form a filter 2'. The main transmission path of the filter 2' is annular. Figure 2 The 6 frequency holes in the Figure 3 The coupling paths between the six frequency holes are shown in Figure 1. Figure 2 The main coupling path of the filter shown is frequency hole 1-frequency hole 2-frequency hole 3-frequency hole 4-frequency hole 5-frequency hole 6. Furthermore, frequency holes 1, 2, and 3 together form a cross-coupling module, and frequency holes 4, 5, and 6 together form a cross-coupling module.

[0088] However, in addition to the above paths, the distances between frequency holes 2 and 4, between frequency holes 3 and 5, and between frequency holes 1 and 6 are relatively close, and there is also redundant parasitic coupling. Therefore, holes are opened in the dielectric block to form an isolation structure to suppress redundant parasitic coupling. Figure 2 The isolation holes 500' and 600' in the filter are used to isolate the energy coupling between frequency holes No. 2 and No. 4, and between frequency holes No. 3 and No. 5, and the isolation holes 600' are used to isolate the energy coupling between frequency holes No. 1 and No. 6. It is understandable that the isolation holes will also reduce the compactness of the filter structure and increase the size of the filter. In addition, when the filter layout is relatively tight, there are more restrictions on the position and size of the isolation holes, and the expected isolation effect may not be achieved, affecting the performance of the filter. On the other hand, the above scheme adjusts the coupling strength between the resonant units through the coupling slot 300', which causes greater damage to the dielectric structure and increases the transmission loss.

[0089] It can be seen from this that in existing filters, it is difficult to achieve compatibility between the decoupling of closely spaced resonant units and the miniaturization of the filter size.

[0090] To this end, the present application provides a resonant unit that can achieve decoupling between closely spaced resonant units simply by arranging and laying out the resonant units in the filter, thereby improving the compactness of the filter structure and reducing the filter size. The structure and operating principle of the resonant unit of the present application are described below with reference to the accompanying drawings.

[0091] See also Figure 4-Figure 6 , Figure 4 This is a schematic diagram of the three-dimensional structure of the first embodiment of the resonance unit of the present application; Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure in the AA direction; Figure 6 Schematic diagram of the positional relationship between the dielectric resonant structure and the resonant slot in the resonant unit of an embodiment of the present application.

[0092] like Figure 4-Figure 6 As shown, the resonance unit 100 includes a dielectric block 1 , which has a top surface 11 and a bottom surface 12 disposed opposite to each other in a first direction z, and a side surface connected between the top surface 11 and the bottom surface 12 .

[0093] It should be noted that the dielectric block 1 illustrated in the drawings of this application is a rectangular parallelepiped structure. In reality, the dielectric block 1 can be considered a block of dielectric material surrounding each resonant unit 100 in the filter 200. Its shape can be cylindrical, prismatic, or irregular, and is not limited to a rectangular parallelepiped structure. The dielectric block can be made of electromagnetic or dielectric materials, such as ceramic, glass, resin, or polymer, and this application does not impose any restrictions on this.

[0094] The top surface 11, bottom surface 12, and side surfaces of the dielectric block 1 can be considered as the spatial surfaces of the dielectric block 1. For example, the first direction z can be the height of the dielectric block 1. Correspondingly, the second direction x represents the length of the dielectric block 1, and the third direction y represents the width of the dielectric block 1. The first direction z, the second direction x, and the third direction y are mutually perpendicular. In this case, the dielectric block 1 has a total of six surfaces: the top surface 11, the bottom surface 12, and the four side surfaces located between the top and bottom surfaces 11 and 12. For ease of description below, the four side surfaces are represented as: a first side surface 131 and a second side surface 132, which are oppositely disposed in the second direction x, and a third side surface 133 and a fourth side surface 134, which are oppositely disposed in the third direction y.

[0095] like Figure 4-Figure 6 As shown, a dielectric block 1 is provided with a resonant slot 2, which is recessed inwardly along a first direction z from either the top surface 11 or the bottom surface 12 of the dielectric block 1. The bottom surface 22 and the wall surfaces 22 of the resonant slot 2 are covered with an electromagnetic shielding layer 3. The resonant slot 2 can be recessed from either the top surface 11 or the bottom surface 12 of the dielectric block 1, and this is not a limitation of the present application. It should be understood that the notch 21 of the resonant slot 2 is located on the inwardly recessed surface of the dielectric block 1.

[0096] Furthermore, the resonant slot 2 includes a first portion 24 and a second portion 25 that are sequentially connected in the first direction z. The first portion 24 penetrates the dielectric block 1 in the second direction x. The notch 241 of the first portion 24 constitutes the notch 21 of the resonant slot 2. The slot bottom surface 252 of the second portion 25 constitutes the slot bottom surface 22 of the resonant slot 2. The notch 251 of the second portion 25 is connected to the slot bottom surface 242 of the first portion 24. Alternatively, the resonant slot 2 can be divided into two parts (the upper and lower parts are Figure 4-Figure 6 From the perspective of the dielectric block 1, the lower portion (i.e., the first portion 24) penetrates the dielectric block 1 in the second direction x and extends from the first side surface 131 to the second side surface 132 of the dielectric block 1. The upper portion (i.e., the second portion 25) is narrower in the second direction x and does not penetrate the dielectric block 1 (e.g., Figure 5 The structure shown in the figure, in which case the cross section of the resonant slot 2 is a "convex" shape), or only one side penetrates the dielectric block 1 (for example Figure 8 The structure shown in FIG. 1 , in which case the cross section of the resonance slot 2 is “L” shaped).

[0097] The bottom surface 22 and the wall surface 23 of the resonant tank 2 are covered with an electromagnetic shielding layer 3, which can be understood as covering the entire inner surface of the resonant tank 2 with the electromagnetic shielding layer 3. The electromagnetic shielding layer 3 can be, for example, a metal coating, etc., which has a shielding effect on electromagnetic signals. The electromagnetic shielding layer 3 on the inner surface of the resonant tank 2 can form a shielding wall, replacing the gaps, isolation grooves, isolation holes and other structures in the prior art to block the transmission path of electromagnetic waves. With this structure, decoupling between resonant units 100 that are relatively close can be achieved only by the layout design of the dielectric unit in the filter 200. The details will be explained later in conjunction with the structure of the filter 200.

[0098] like Figure 4-Figure 6 As shown, a dielectric resonant structure 4 is formed in the area surrounding the groove bottom surface 242 of the first portion 24 and the second portion 25 of the dielectric block 1. The dielectric resonant structure 4 is U-shaped or L-shaped in a plane perpendicular to the third direction y (i.e., the cross-section of the dielectric resonant structure 4 is U-shaped or L-shaped). The resonant frequency of the dielectric resonant structure 4 is related to the length of the dielectric resonant structure 4. Specifically, the area surrounding the groove bottom surface 242 of the first portion 24 and the second portion 25 includes: the area enclosed by the groove bottom surface 242 of the first portion 24, the two sidewall surfaces 253 of the second portion 25 in the second direction x, the groove bottom surface 252 of the second portion 25, and the outer surface of the dielectric block 1. Alternatively, it can be understood that Figure 6 The dielectric between the shaded surfaces and the outer surface of the dielectric block 1 constitutes a dielectric resonant structure 4. The dielectric resonant structure 4 is U-shaped or L-shaped in a plane perpendicular to the third direction y, and the resonant frequency of the dielectric resonant structure 4 is related to the length of the dielectric resonant structure 4.

[0099] like Figure 5 As shown, taking the dielectric resonant structure 4 with a U-shaped cross section as an example, the dielectric resonant structure 4 has a bottom 41 extending along the second direction x, and two connecting arms 42 connected to both sides of the bottom 41, and each connecting arm 42 extends along the first direction z. The dielectric resonant structure 4 extends in a U-shape as a whole, and its total length is L0. L0 is related to the resonant frequency of the dielectric resonant structure 4. Changing L0 can change the resonant frequency of the dielectric resonant structure 4, that is, change the operating frequency of the resonant unit 100. In other words, the total length L0 of the dielectric resonant structure 4 is designed according to the required operating frequency of the resonant unit 100. It should be noted that L0 is the length of the dielectric resonant structure 4 along its extension direction, and should be measured from the center position of the dielectric resonant structure 4. For example, Figure 5The length L0 of the dielectric resonant structure 4 is the distance from the left groove bottom surface 242 of the first portion 24 along the U-shaped line to the right groove bottom surface 242. This length L0 can be broken down into the following components: the length L1 of the left connecting arm 42, the length L2 of the bottom portion 41, and the length L3 of the right connecting arm 42, where L0 = L1 + L2 + L3. It should be noted that the lengths L1 and L3 of the two connecting arms 42 can be equal or unequal, as long as the total length L0 of the dielectric resonant structure 4 is relevant to its resonant frequency, and thus falls within the scope of protection of this application.

[0100] See also Figure 7-Figure 8 , Figure 7 Schematic diagram of the cross-sectional structure of the second embodiment of the resonance unit of the present application; Figure 8 Schematic diagram of the cross-sectional structure of the third embodiment of the resonance unit of the present application.

[0101] Figure 7 and Figure 8 for Figure 5 Two variations of Figure 5 The length of the connecting arm 42 of the dielectric resonant structure 4 is changed based on Figure 5 As shown, in one embodiment, the dielectric resonant structure 4 is U-shaped in a plane perpendicular to the third direction y, and the two connecting arms 42 have the same length, L1 = L3. Figure 7 As shown, in one embodiment, the dielectric resonant structure 4 is U-shaped in a plane perpendicular to the third direction y, and the two connecting arms 42 thereof are of different lengths, L1≠L3. Figure 8 As shown in FIG. 1 , in one embodiment, the dielectric resonant structure 4 is L-shaped in a plane perpendicular to the third direction y, and the length of one connecting arm 42 thereof is 0. Alternatively, it can be understood that, while ensuring that the total length of the dielectric resonant structure 4 remains unchanged, Figure 5 One of the connecting arms 42 is shortened to zero length, and only the other connecting arm 42 is retained, thereby forming an L-shaped dielectric resonant structure 4 in a plane perpendicular to the third direction y. This solution is also within the protection scope of this application.

[0102] The resonance unit 100 provided in the embodiment of the present application has a resonance slot 2 provided in the dielectric block 1. Through the shape design of the resonance slot 2, the area around the resonance slot 2 forms a dielectric resonance structure 4 with a U-shaped or L-shaped cross-section. On the one hand, the dielectric resonance structure 4 can excite a resonance mode (the electric field around the resonance slot 2 is distributed within the dielectric resonance structure 4), so that the resonance unit 100 can work normally in the filter 200. In addition, the resonant frequency of the dielectric resonance structure 4 is related to its length. By changing the length of the dielectric resonance structure 4, the operating frequency of the resonance unit 100 can be adjusted. On the other hand, the resonance slot 2 itself can be used as an isolation slot, and the electromagnetic shielding layer 3 covering the bottom surface 22 and the wall surface of the resonance slot 2 can serve as a partition wall to shield the electromagnetic signal. There is no need to add gaps, isolation grooves, holes and other structures in the filter 200. By simply arranging and laying out the resonant units 100 in the filter 200, signal coupling and signal decoupling between different resonant units 100 (including decoupling between resonant units 100 that are relatively close to each other) can be achieved simultaneously, which is beneficial to improving the compactness of the filter 200 structure and reducing the size of the filter 200.

[0103] It can be seen that the resonance unit provided in the embodiment of the present application can take into account both the decoupling between the resonance units that are relatively close in the filter and the miniaturization of the filter size.

[0104] Compared to Figures 1 to 3 As shown in the scheme, the resonance unit 100 provided in the embodiment of the present application can also reduce the transmission loss of the filter 200 and can achieve a better decoupling effect between the resonance units 100, which will be specifically described later in conjunction with the structure of the filter 200.

[0105] See also Figure 9-11b , Figure 9 This is a diagram of an electric field simulation test of a resonant unit according to an embodiment of the present application; Figure 10 Schematic diagram of the cross-sectional structure of a fourth embodiment of the resonance unit of the present application; Figure 11a A side view of a first embodiment of a resonance unit according to an embodiment of the present application; Figure 11b This is a side view of a fifth embodiment of the resonance unit of the present application.

[0106] like Figure 9 As shown, Figure 9The arrow in the middle indicates the direction of the electric field in the dielectric resonant structure 4. It can be seen that in the resonant mode of the resonant unit 100 of the present application, the direction of the electric field in the dielectric resonant structure 4 is distributed as follows: vertically outward from the inner side surface of the dielectric resonant structure 4. Among them, the inner side surface of the dielectric resonant structure 4 includes the groove bottom surface 242 of the first part 24, the two side wall surfaces 253 of the second part 25 in the second direction x, and the groove bottom surface 252 of the second part 25. It can be understood that the core solution of the present application is to form a dielectric resonant structure 4 extending along a U-shaped or L-shaped path by opening a resonant groove 2 on the dielectric block 1, and covering the entire inner surface of the resonant groove 2 with an electromagnetic shielding layer 3, so that the resonant unit 100 works in Figure 9 The present application does not limit the shape of the dielectric block 1, the specific shape of the resonant slot 2, the specific shape and size of the dielectric resonant structure 4, and the shape of each wall of the resonant slot 2. The structure of the resonant unit 100 will be further expanded with reference to the accompanying drawings.

[0107] like Figure 4-Figure 6 As shown, in one embodiment, the bottom surface 22 and the wall surface 23 of the resonant slot 2 are both planes. In other alternative implementations, the bottom surface 22 and the wall surface 23 of the resonant slot 2 can also be curved surfaces, arc surfaces, or a combination of a plane, a curved surface, or an arc surface. For example, Figure 10 A possible solution is illustrated. The bottom surface 252 of the second portion 25 of the resonant slot 2 and the smooth transition between the two slot walls opposite each other in the second direction x are both formed by combining curved and flat surfaces. Despite the changes in the shapes of several surfaces, a U-shaped or L-shaped dielectric resonant structure 4 can still be formed.

[0108] like Figure 11a As shown, in one embodiment, for the convenience of processing, the two sidewall surfaces 231 of the resonance slot 2 that are opposite to each other in the third direction y are set as planes perpendicular to the third direction y. In other alternative embodiments, the sidewall surfaces 231 may also be curved surfaces, arc surfaces, etc., or may also be planes that are not perpendicular to the third direction y. Figure 11b As shown, in one embodiment, the two sidewalls 231 of the resonance slot 2 that are opposite to each other in the third direction y are both planes inclined to the first direction z, and the angle between them and the third direction y is non-right angle, that is, the sidewalls 231 are not perpendicular to the third direction y. Figure 5 As shown, in one embodiment, the two sidewall surfaces 253 of the second portion 25 of the resonance slot 2 are arranged opposite to each other in the second direction x and are both arranged as planes perpendicular to the second direction x. Similarly, the sidewall surfaces 253 may not be perpendicular to the second direction x, which is not given as an example here.

[0109] like Figure 5As shown, in one embodiment, within a plane perpendicular to the third direction y, the widths of the dielectric resonant structure 4 along its extension direction are the same. Specifically, the width of the left connecting arm 42 of the dielectric resonant structure 4 is w1, the width of the bottom 41 is w2, and the width of the right connecting arm 42 is w3, where w1 = w2 = w3. In other alternative embodiments, the widths of the various portions of the dielectric structure along its extension direction may also be unequal, and this application is not limited thereto.

[0110] Those skilled in the art will appreciate that the resonant frequency of the dielectric resonant structure 4 is related to its total length L0. Therefore, adjusting the total length L0 of the dielectric resonant structure 4 can adjust its resonant frequency, thereby adjusting the operating frequency of the resonant unit 100. In other words, designing the total length L0 of the dielectric resonant structure 4 based on the desired operating frequency of the resonant unit 100 is crucial to the design of the filter 200. The resonant frequency of the dielectric resonant structure 4 is represented by f0. It will be appreciated that a correlation exists between f0 and L0. When this correlation is satisfied, the other structures and dimensions of the resonant unit 100 can be flexibly modified. This allows the resonant unit 100 to be more flexible and diverse in shape and structure, rather than being restricted to a single form, making it suitable for a wider range of filters 200.

[0111] In one embodiment, the correlation between f0 and L0 is: Where c is the speed of light in vacuum, ε r is the relative dielectric constant of the dielectric block 1. Or it can be understood that L0 is approximately the half wavelength of the signal with a frequency of f0 in the medium, that is, (λ g is the wavelength of the signal in the medium). The preset threshold can be set as needed. If k represents the preset threshold, In an example scenario, f0 = 3 × 10 8 Hz, ε r =6, c = 3 × 10 8 m / s, then half wavelength Should be For example, k is set to 10 mm, and L0 is within the range of 194 mm to 214 mm.

[0112] The foregoing mainly describes the structure and working principle of the resonance unit 100 of the present application. The following will illustrate the usage scenario of the resonance unit 100 with reference to the structure of the filter 200.

[0113] See also Figure 12-14 , Figure 12 This is a schematic diagram of the three-dimensional structure of the first embodiment of the filter of the present application; Figure 13 for Figure 12 Schematic diagram of the topology of the filter; Figure 14This is a schematic diagram of the three-dimensional structure of the second embodiment of the filter of the embodiment of the present application.

[0114] like Figure 12 As shown, an embodiment of the present application further provides a filter 200. It should be noted that the filter 200 can be a microwave filter, a radio wave filter, a millimeter wave filter, a low-pass filter, a high-pass filter, a band-pass filter, a band-stop filter, etc., and the present application does not limit this. In one embodiment, the filter 200 is a microwave filter, operating in the microwave frequency band. The filter 200 includes a plurality of resonant units, and at least one of the plurality of resonant units adopts the resonant unit 100 provided in the present application. Among them, the specific number of resonant units is not limited, and can be 2, 3, 4 or more. The plurality of resonant units can all adopt the resonant unit 100 provided in the present application, or a part can adopt the resonant unit 100 provided in the present application, and the other part can adopt other types of resonant units, and the present application does not limit this.

[0115] like Figure 12-13 As shown, in one embodiment, the filter 200 includes five resonant units arranged in sequence along a fourth direction s, namely a first resonant unit 51, a second resonant unit 52, a third resonant unit 53, a fourth resonant unit 54, and a fifth resonant unit 55. The fourth direction s is the direction in which the resonant units are arranged, which can be a straight line direction or a curved line direction, and this application does not impose any restrictions on this. In one embodiment, the fourth direction s is a straight line direction. The filter 200 with the resonant units arranged in a straight line has a simple structure, the main transmission path is a straight line, and the energy coupling between different resonant units is easy to control and debug.

[0116] Furthermore, in one embodiment, the five resonant units all adopt the resonant unit 100 provided in this application. Or it can be understood that the filter 200 is composed of five resonant units arranged along the fourth direction s. It should be noted that the placement angle of each resonant unit in the filter 200 is not limited. Figure 12 As shown, in one embodiment, the third direction y of each resonant unit 100 is parallel to the fourth direction s. Alternatively, it can be understood that the resonant slots 2 of each resonant unit 100 are parallel to each other, and the third side surfaces 133 and fourth side surfaces 134 of adjacent resonant units 100 are in contact. For example, among two adjacent resonant units 100, the fourth side surface 134 of one resonant unit 100 is in contact with the third side surface 133 of the other resonant unit 100. In other alternative embodiments, the resonant slots 2 of each resonant unit 100 may also be non-parallel. For example, any one or more resonant units 100 may be twisted so that the second direction x of the resonant unit 100 is parallel to the fourth direction s, and the resonant slot 2 of the twisted resonant unit 100 is perpendicular to the resonant slots 2 of the other resonant units 100.

[0117] like Figure 13 As shown, Figure 12 The main transmission path of the filter 200 is: the first resonance unit 51-the second resonance unit 52-the third resonance unit 53-the fourth resonance unit 54-the fifth resonance unit 55, and energy coupling is performed between adjacent resonance units. It can be understood by those skilled in the art that the signal (which can be an electromagnetic wave signal or a radio frequency signal) is transmitted in the medium of the filter 200. The more medium there is between adjacent resonance units 100, the higher the coupling strength between the two. Therefore, the length of the connecting arm 42 of the dielectric resonance structure 4 in each resonance unit 100 can be adjusted to change the coupling strength between it and the adjacent resonance unit 100. In an example scenario, as Figure 14 As shown, the dielectric resonant structure 4 of the first resonant unit 51 is designed to be a dielectric resonant structure 4 extending in a U shape, and the dielectric resonant structure 4 of the second resonant unit 52 is designed to be a dielectric resonant structure 4 extending in an L shape. If the two dielectric resonant units 100 are asymmetrical, there will be less dielectric in the area where they are facing each other in the fourth direction s, and the coupling strength will be weaker. On the contrary, if the dielectric resonant structures 4 of the two resonant units 100 are designed to be symmetrical structures with exactly the same shape and size, the coupling strength between the two will be higher. This is the principle of the filter 200 of the present application for adjusting the coupling strength between adjacent resonant units 100. Compared to Figures 1 to 3 The method of adjusting the coupling strength between the resonant units through the coupling slot 300' does not damage the dielectric structure, thereby reducing transmission loss and having the same advantages in adjusting the coupling strength. Of course, the method of adjusting the coupling strength in the filter 200 of the present application is not limited to adjusting the length of the connecting arm 42 of the dielectric resonant structure 4. It can also be used to adjust the distance between adjacent resonant units, and this application does not limit this.

[0118] Those skilled in the art will appreciate that, in the above structure, the first resonant unit 51 and the third resonant unit 53 are relatively close to each other. To prevent unwanted parasitic coupling between them, an isolation structure is required to block the coupling path between them. Similarly, an isolation structure is required between the second resonant unit 52 and the fourth resonant unit 54, and between the third resonant unit 53 and the fifth resonant unit 55.

[0119] like Figure 12As shown, in one embodiment, the notch 21 of the resonant slot 2 of the third resonant unit 53 is oriented oppositely to the notch 21 of the resonant slot 2 of the other resonant units 100. Alternatively, it can be understood that the dielectric resonant structure 4 of the third resonant unit 53 is located at the lower position in the figure, while the dielectric resonant structures 4 of the other resonant units 100 are located at the upper position in the figure. With this structure, the resonant slot 2 of the third resonant unit 53 is located between the dielectric resonant structure 4 of the second resonant unit 52 and the dielectric resonant structure 4 of the fourth resonant unit 54. The electromagnetic shielding layer 3 covering the inner surface of the resonant slot 2 of the third resonant unit 53 acts as a partition wall, shielding the signal transmission between the second resonant unit 52 and the fourth resonant unit 54. Although the signal can bypass the dielectric below the third resonant unit 53 and transmit between the second resonant unit 52 and the fourth resonant unit 54, this energy coupling is very weak and can be ignored. Similarly, the resonant slot 2 of the second resonant unit 52 is located between the dielectric resonant structure 4 of the first resonant unit 51 and the dielectric resonant structure 4 of the third resonant unit 53, shielding the signal transmission between the two. The resonant slot 2 of the fourth resonant unit 54 is located between the dielectric resonant structure 4 of the third resonant unit 53 and the dielectric resonant structure 4 of the fifth resonant unit 55, shielding the signal transmission between the two. It can be seen that the filter 200 of the present application can achieve decoupling between resonant units 100 that are relatively close to each other simply by the layout of the resonant units.

[0120] See also Figure 15-17 , Figure 15 Schematic diagram of the three-dimensional structure of the third embodiment of the filter of the present application; Figure 16 for Figure 15 Schematic diagram of the topology of the filter; Figure 17 Schematic diagram of the three-dimensional structure of the second resonance unit in the third embodiment of the filter of the embodiment of the present application.

[0121] like Figure 15 As shown, in one embodiment, the filter 200 includes a first resonance unit 51, a second resonance unit 52, a third resonance unit 53, a fourth resonance unit 54 and a fifth resonance unit 55 arranged in sequence along the fourth direction s. Figure 12 The structure is different in that each resonance unit in the first resonance unit 51, the third resonance unit 53 and the fifth resonance unit 55 adopts the resonance unit 100 provided in this application, and each resonance unit in the second resonance unit 52 and the fourth resonance unit 54 is a resonance unit of other types.

[0122] Specifically, each of the second resonant unit 52 and the fourth resonant unit 54 includes a dielectric block 6, which is provided with a columnar resonant slot 61. The columnar resonant slot 61 is recessed inwardly along the fifth direction d from one side surface of the dielectric block 6 in the fifth direction d, and the inner surface of the columnar resonant slot 61 is covered with an electromagnetic shielding layer 62. The fifth direction d can be understood as the recessed direction of the columnar resonant slot 61. Figure 17 As shown in the figure, the arrows indicate the electric field distribution within the resonance unit. The columnar resonance slot 61 can excite a resonance mode different from the resonance unit 100 of the present application. Specifically, the resonance unit 100 in the present application operates in the form of a half-wavelength resonator, and the operating frequency is mainly determined by the length L0 of the dielectric resonant structure. As for the columnar resonance slot 61, it mainly operates in the form of a quarter-wavelength resonator with a short circuit at the terminal. When the size of the surrounding dielectric is determined, its operating frequency is mainly determined by the depth of the columnar resonance slot 61. It should be noted that any surface of the dielectric block 6 can be recessed to form the columnar resonance slot 61, and this application does not impose any restrictions on this.

[0123] like Figure 15 As shown, in one embodiment, the third direction y of each of the first resonant unit 51, the third resonant unit 53, and the fifth resonant unit 55 is parallel to the fourth direction s (i.e., the resonant slots 2 of the first resonant unit 51, the third resonant unit 53, and the fifth resonant unit 55 are arranged in parallel), and the orientation of the notch 21 of the resonant slot 2 of the first resonant unit 51 is opposite to the orientation of the notch 21 of the resonant slot 2 of the third resonant unit 53 and the orientation of the notch 21 of the resonant slot 2 of the fifth resonant unit 55. The notch 21 of the columnar resonant slot 61 of the second resonant unit 52 and the columnar resonant slot 61 of the fourth resonant unit 54 are in the same orientation, and are both perpendicular to the orientation of the notch 21 of the resonant slot 2 of the first resonant unit 51 and the orientation of the notch 21 of the resonant slot 2 of the third resonant unit 53.

[0124] like Figure 17As shown, with this structure, energy coupling exists between the first resonant unit 51 and the third resonant unit 53, and energy coupling also exists between the second resonant unit 52 and the first resonant unit 51 and the third resonant unit 53, respectively. Thus, the first resonant unit 51, the second resonant unit 52, and the third resonant unit 53 together constitute a cross-coupling module. Because the notches 21 of the resonant slots 2 of the first resonant unit 51 and the third resonant unit 53 face opposite directions, the cross-coupling between them is capacitive (negative) coupling. The two transmission paths of this cross-coupling module (path 1-third resonant unit 53 and path first resonant unit 51-second resonant unit 52-third resonant unit 53) have opposite phases. When superimposed, they generate a transmission zero at the low-frequency end of the operating passband of the filter 200, thereby improving the suppression of low-frequency signals. Similarly, the third resonant unit 53, the fourth resonant unit 54, and the fifth resonant unit 55 together constitute a cross-coupling module. Since the notches 21 of the resonant slots 2 of the third resonant unit 53 and the fifth resonant unit 55 are oriented in the same direction, the cross-coupling between them is inductive (positive) coupling. The two transmission paths of the cross-coupling module (the path from the third resonant unit 53 to the fifth resonant unit 55 and the path from the third resonant unit 53 to the fourth resonant unit 54 to the fifth resonant unit 55) are in the same phase. After superposition, a transmission zero is generated at the high-frequency end of the working passband of the filter 200, thereby improving the suppression of high-frequency signals. It can be seen that the use of the resonant unit 100 in combination with other resonant units in the filter 200 of the present application can achieve more diverse functions and optimize the performance of the filter 200.

[0125] Those skilled in the art will appreciate that, in the above structure, the distance between the second resonant unit 52 and the fourth resonant unit 54 is relatively close, and in order to avoid unwanted parasitic coupling between the two, an isolation structure needs to be designed to block the coupling path between the two. Figure 15 As shown, in one embodiment, the columnar resonant slot 61 of the second resonant unit 52 is arranged between the notch 21 and the bottom surface 22 of the resonant slot 2 of the third resonant unit 53 in the first direction z, and the columnar resonant slot 61 of the fourth resonant unit 54 is also arranged between the notch 21 and the bottom surface 22 of the resonant slot 2 of the third resonant unit 53 in the first direction z. With this structure, the resonant slot 2 of the third resonant unit 53 is blocked between the columnar resonant slot 61 of the second resonant unit 52 and the fourth resonant unit 54, and the electromagnetic shielding layer 3 covering the inner surface of the resonant slot 2 of the third resonant unit 53 acts as a partition wall to shield the signal transmission between the two. Although the signal can bypass the medium below the third resonant unit 53 and transmit between the second resonant unit 52 and the fourth resonant unit 54, this energy coupling is very weak and can be ignored. It can be seen that the resonant unit 100 is used in combination with other resonant units in the filter 200 of the present application, and decoupling between resonant units that are close to each other can also be achieved through the layout of the resonant units.

[0126] See also Figure 18 , Figure 18 This is a schematic diagram of the three-dimensional structure of the fourth embodiment of the filter of the embodiment of the present application.

[0127] like Figure 18 As shown, in one embodiment, the filter 200 includes five resonance units arranged in sequence along the fourth direction s, namely a first resonance unit 51, a second resonance unit 52, a third resonance unit 53, a fourth resonance unit 54, and a fifth resonance unit 55. The first resonance unit 51 and the third resonance unit 53 use the resonance unit 100 provided in the present application, and the third direction y of each resonance unit in the first resonance unit 51 and the third resonance unit 53 is parallel to the fourth direction s, and the notch 21 of the resonance slot 2 of the first resonance unit 51 is oriented opposite to the notch 21 of the resonance slot 2 of the third resonance unit 53.

[0128] Each of the second resonant unit 52, the fourth resonant unit 54, and the fifth resonant unit 55 includes a dielectric block 6, which is provided with a columnar resonant slot 61. The columnar resonant slot 61 is recessed inwardly along the fifth direction d from one side surface of the dielectric block 6 in the fifth direction d, and the inner surface of the columnar resonant slot 61 is covered with an electromagnetic shielding layer 62. The notch 21 of the columnar resonant slot 61 of the fifth resonant unit 55 is oriented in the same direction as the notch 21 of the resonant slot 2 of the third resonant unit 53. The notch 21 of the columnar resonant slot 61 of the second resonant unit 52 is oriented in the same direction as the opening of the columnar resonant slot 61 of the fourth resonant unit 54, and both are perpendicular to the notch 21 of the columnar resonant slot 61 of the fifth resonant unit 55. Alternatively, it can be understood that Figure 18 The solution is Figure 15 A variation of the scheme will Figure 15 The fifth resonance unit 55 is replaced by a resonance unit provided with a columnar resonance slot 61. Figure 18 The topology of the filter in the scheme is Figure 16 The signal transmission path of the filter and the coupling mode between the resonant units are similar to Figure 15 The scheme is the same as that of , and will not be repeated here.

[0129] It will be understood by those skilled in the art that the filter 200 is composed of a plurality of resonance units 100 arranged in parallel, and each resonance unit 100 has a dielectric block. In one embodiment, the dielectric block of the plurality of resonance units 100 is provided as an integral structural dielectric block. Or it can be understood that all the resonance units 100 in the filter 200 are designed as an integral structure, which can be directly processed and formed on a structural block. Furthermore, the outer surface of the integral structural dielectric block is covered with an electromagnetic shielding layer 71 to confine the signal to the dielectric of the filter 200. It will be understood that the filter 200 has an input terminal 72 and an output terminal 73, and the positions of the input terminal 72 and the output terminal 73 can be set according to the designed transmission path. For example, Figure 12 The input end 72 of the filter 200 can be set on any surface of the first resonance unit 51, such as the top surface 11, side surface, bottom surface 12, etc. of the dielectric block 1, and the output end 73 of the filter 200 can be set on any surface of the fifth resonance unit 55. This application does not impose any restrictions on this.

[0130] See also Figure 19 , Figure 19 This is a schematic diagram of the system structure of the base station in an embodiment of the present application.

[0131] like Figure 19 As shown, the present application further provides a base station 300, in which the filter 200 provided by the present application is applied. The base station 300 can be a wireless base station, a wired base station, a macro base station, a micro base station, a remote radio frequency base station, a close radio frequency base station, an intelligent base station, etc., and the present application does not limit this. The following uses a wireless base station as an example to illustrate the role and working mode of the filter 200 in the base station 300.

[0132] like Figure 19 As shown, in one embodiment, the base station 300 includes an antenna 81, an indoor baseband processing unit 82 (Building Baseband Unit, BBU), and a remote radio module 83 (Remote Radio Unit, RRU). The antenna 81 can send signals to the remote radio module 83 or receive signals from the remote radio module 83. The indoor baseband processing unit 82 is usually installed in the base station 300 equipment room and is responsible for processing and converting digital signals, including encoding, multiplexing, modulation, and spread spectrum. The remote radio module 83 is installed near the antenna 81 and is responsible for converting digital signals into wireless signals and sending them to the antenna 81 to reduce signal transmission loss and delay.

[0133] In one embodiment, the remote RF module 83 includes a digital system 821, a RF transceiver system 822, and multiple filters 200 located outside the RF transceiver system 822. Multiple filters 200 are also provided within the RF transceiver system 822. It should be noted that the number of filters 200 located inside and outside the RF transceiver system 822 is not limited and depends on the number of signal transmission lines. The figure illustrates four transmission lines, with four filters 200 each located inside and outside the RF transceiver system 822. The figure shows two transmitting lines and two receiving lines. A low noise amplifier 85 (LNA) is installed on the top of each receiving line. The signal line emitted from the antenna 81 is filtered by the filter 200 outside the RF transceiver system 822. The noise is reduced by the low noise amplifier 85 to maintain the clarity and accuracy of the signal. Then it enters the RF transceiver system 822 and is filtered twice in the filter 200 inside the RF transceiver system 822. Thereafter, it is transmitted by the RF transceiver system 822 to the digital signal system for analysis and processing, and finally transmitted to the indoor baseband processing unit 82. A power amplifier (PA) 84 is installed above each transmission line. The signal sent from the indoor baseband processing unit 82 is first analyzed by the digital system 821, then transmitted to the filter 200 in the RF transceiver system 822 for the first filtering. The power is then amplified by the power amplifier 84, and then enters the filter 200 for a second filtering before being transmitted to the antenna 81. Whether transmitting or receiving, the signal passes through the filter twice, which can accurately filter the required signal and suppress other clutter signals.

[0134] It will be understood by those skilled in the art that Figure 19 The base station 300 in the figure is only a schematic diagram. In practice, the base station 300 may include Figure 19 This application does not limit the configuration to more or less structures.

[0135] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A resonance unit, characterized in that: The resonant unit includes a dielectric block having a top surface and a bottom surface disposed opposite to each other in a first direction, and a side surface connected between the top surface and the bottom surface; the dielectric block is provided with a resonant slot, the resonant slot being recessed inwardly along the first direction from the top surface or the bottom surface of the dielectric block; the slot bottom surface and slot wall surfaces of the resonant slot being covered with an electromagnetic shielding layer; The resonant slot includes a first portion and a second portion sequentially connected in the first direction, the first portion penetrates the dielectric block in the second direction, and a notch of the first portion constitutes a notch of the resonant slot; The groove bottom surface of the second portion constitutes the groove bottom surface of the resonant groove, the groove opening of the second portion is connected to the groove bottom surface of the first portion, and a dielectric resonant structure is formed in the area of ​​the dielectric block located at the groove bottom surface of the first portion and around the second portion. The dielectric resonant structure is U-shaped or L-shaped in a plane perpendicular to the third direction, and the resonant frequency of the dielectric resonant structure is related to the length of the dielectric resonant structure. The first direction, the second direction, and the third direction are perpendicular to each other.

2. The resonance unit according to claim 1, wherein The bottom surface and the wall surface of the resonance groove are both planes.

3. The resonance unit according to claim 1 or 2, characterized in that: The two sidewall surfaces of the resonance slot that are opposite to each other in the third direction are both configured as planes that are perpendicular to the third direction.

4. The resonance unit according to any one of claims 1 to 3, characterized in that: Two sidewall surfaces of the second portion of the resonance slot that are opposite to each other in the second direction are both configured as planes perpendicular to the second direction.

5. The resonance unit according to any one of claims 1 to 4, characterized in that: In a plane perpendicular to the third direction, each portion of the dielectric resonant structure along its extending direction has the same width.

6. The resonance unit according to any one of claims 1 to 5, characterized in that: The total length of the dielectric resonant structure is L0, and the resonant frequency of the dielectric resonant structure is f0. The difference is within the preset threshold range, where c is the speed of light in vacuum, ε r is the relative dielectric constant of the dielectric block.

7. A filter comprising a plurality of resonant units, characterized in that: At least one of the plurality of resonance units is the resonance unit according to any one of claims 1 to 6.

8. The filter according to claim 7, wherein The multiple resonance units include five resonance units arranged in sequence along the fourth direction, namely a first resonance unit, a second resonance unit, a third resonance unit, a fourth resonance unit and a fifth resonance unit, and each of the five resonance units is a resonance unit according to any one of claims 1 to 6; The third direction of each of the resonance units is parallel to the fourth direction, and the notch direction of the resonance slot of the third resonance unit is opposite to the notch direction of the resonance slots of other resonance units.

9. The filter according to claim 7, wherein The plurality of resonance units include five resonance units sequentially arranged along the fourth direction, namely a first resonance unit, a second resonance unit, a third resonance unit, a fourth resonance unit and a fifth resonance unit; wherein, Each of the first resonant unit, the third resonant unit, and the fifth resonant unit is a resonant unit according to any one of claims 1 to 6, and the third direction of each of the first resonant unit, the third resonant unit, and the fifth resonant unit is parallel to the fourth direction, and a notch orientation of the resonant slot of the first resonant unit is opposite to a notch orientation of the resonant slot of the third resonant unit and a notch orientation of the resonant slot of the fifth resonant unit; Each of the second resonant unit and the fourth resonant unit includes a dielectric block, the dielectric block is provided with a columnar resonant slot, the columnar resonant slot is recessed inwardly along the fifth direction from a side surface of the dielectric block in the fifth direction, and the inner surface of the columnar resonant slot is covered with an electromagnetic shielding layer; the columnar resonant slot of the second resonant unit and the columnar resonant slot of the fourth resonant unit have the same slot opening orientation, and are both perpendicular to the slot opening orientation of the resonant slot of the first resonant unit and the slot opening orientation of the resonant slot of the third resonant unit.

10. The filter according to claim 7, wherein The plurality of resonance units include five resonance units sequentially arranged along the fourth direction, namely a first resonance unit, a second resonance unit, a third resonance unit, a fourth resonance unit and a fifth resonance unit; wherein, The first resonant unit and the third resonant unit are the resonant units according to any one of claims 1 to 6, and the third direction of each of the first resonant unit and the third resonant unit is parallel to the fourth direction, and the notch of the resonant slot of the first resonant unit is oriented opposite to the notch of the resonant slot of the third resonant unit; Each of the second resonant unit, the fourth resonant unit, and the fifth resonant unit includes a dielectric block, the dielectric block is provided with a columnar resonant slot, the columnar resonant slot is recessed inward along the fifth direction from a side surface of the dielectric block in the fifth direction, and the inner surface of the columnar resonant slot is covered with an electromagnetic shielding layer; the slot opening direction of the columnar resonant slot of the fifth resonant unit is the same as the slot opening direction of the resonant slot of the third resonant unit, the slot opening direction of the columnar resonant slot of the second resonant unit is the same as the opening direction of the columnar resonant slot of the fourth resonant unit, and both are perpendicular to the slot opening direction of the columnar resonant slot of the fifth resonant unit.

11. The filter according to any one of claims 8 to 10, characterized in that The fourth direction is a straight line direction.

12. The filter according to any one of claims 7 to 11, wherein: The dielectric blocks of the plurality of resonance units are configured as an integrated structural dielectric block, and an outer surface of the integrated structural dielectric block is covered with an electromagnetic shielding layer.

13. A base station, characterized in that: The base station comprises the filter according to any one of claims 7-12.

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