Band-pass filter of asymmetric SIR
By designing asymmetric SIR bandpass filters, using multi-path coupling and electromagnetic hybrid coupling technology, the problem of insufficient spectrum selection and broadband suppression capabilities of microwave millimeter wave filters is solved, and a small filter with low cost and high yield is realized, with excellent frequency selectivity and wide stopband suppression capabilities, adapting to circuits of different bandwidths.
Patent Information
- Application Number
- CN202422364368.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-27
AI Technical Summary
The existing microwave millimeter wave filters have shortcomings in spectrum selection capabilities and broadband suppression capabilities, and technical indicators such as transmission insertion losses and circuit size need to be improved.
A band-pass filter with asymmetric SIR is designed, including a top copper plating layer, an intermediate dielectric plate layer and a bottom copper plating layer, ground metal holes and input and output ports, and is mass-made using a simple printed circuit board process. It forms a transmission zero point through multi-path coupling and electromagnetic hybrid coupling, and optimizes frequency selectivity and stopband suppression capabilities.
It realizes a small filter with low cost and high yield, with excellent frequency selectivity and wide stopband suppression capabilities, low insertion loss, and the bandwidth can be flexibly adjusted by adjusting the length of the low impedance part of the SIR to adapt to circuits of different bandwidths.
Smart Images
Figure CN223093094U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of microwave and millimeter-wave filters, and specifically relates to a band-pass filter with an asymmetric SIR. Background Art
[0002] Microwave and millimeter-wave filters are very important components in modern radar and communication systems. Their function is to couple useless radio frequency signals to the ground or prevent them from passing through, and only pass useful signals, which can ensure the spectral purity of the circuit or system and avoid the formation of electromagnetic wave pollution caused by the spread of useless signals in space.
[0003] In order to enhance the spectral selection ability of the filter as much as possible, attention must be paid to the two important technical indicators of the filter: the sideband selection ability and the broadband suppression ability; at the same time, in order to further meet the high requirements of the system and circuit, the filter also needs to focus on technical indicators such as the transmission insertion loss and circuit size of the filter.
[0004] In summary, the utility model provides a band-pass filter with an asymmetric SIR to solve the above problems. Content of the Utility Model
[0005] In order to solve the above technical problems, the utility model provides the following technical solutions:
[0006] A band-pass filter with an asymmetric SIR includes a top copper-plated layer, an intermediate dielectric layer, and a bottom copper-plated layer. The intermediate dielectric layer is arranged at the bottom of the top copper-plated layer, and the bottom copper-plated layer is arranged at the bottom of the intermediate dielectric layer. The bottom copper-plated layer is a fully copper-plated layer connected to the ground. The top copper-plated layer further includes an asymmetric SIR, a grounding metal hole, and input / output ports.
[0007] Further, in the utility model, the number of the grounding metal holes is four, and the four grounding metal holes are rotationally distributed at intervals of 90 degrees around the central grounding metal hole, showing central symmetry.
[0008] Further, in the utility model, the number of the input / output ports is two. The signals of the two input / output ends are 50 ohms, and they are connected to the high-impedance lines of the two SIRs. The input / output ports are distributed in reverse central symmetry.
[0009] Further, in the utility model, the thicknesses of the top copper-plated layer and the bottom copper-plated layer are both 0.035 mm, and the bottom copper-plated layer and the top copper-plated layer are respectively located on both sides of the intermediate dielectric layer.
[0010] Further, in the utility model, the thickness of the bottom copper-plated layer is 0.254 mm, and the Rogers 5880 substrate is used.
[0011] Advantageous effects: The utility model has the following advantageous effects:
[0012] In the case of achieving excellent performance, the circuit structure of the utility model is simple, and it can be mass-produced by using a simple printed circuit board process. Moreover, the processing accuracy can be well controlled, the yield rate is high, which ensures the advantage of low cost. The size of this filter is 10.4mm * 10.4mm, achieving a very small size, that is, the guided wavelength is 0.23λ * 0.23λ, and it has excellent high selectivity in the upper sideband of the frequency and wide stopband suppression ability (up to the 2.5th harmonic), with a small insertion loss of 0.55dB and excellent return loss of -20dB. Secondly, without affecting other technical indicators, only by changing the length of the low-impedance part of the SIR can the bandwidth of the filter be changed, which enhances the high adaptability of the filter to circuits with different bandwidths. Description of the drawings
[0013] Figure 1 is a schematic structural diagram of the utility model;
[0014] Figure 2 is a size diagram of the band-pass filter with an asymmetric SIR;
[0015] Figure 3 is a coupling topology analysis diagram of the band-pass filter with an asymmetric SIR;
[0016] Figure 4 are the S parameters of the band-pass filter with an asymmetric SIR;
[0017] Figure 5 is the bandwidth tuning performance of the band-pass filter with an asymmetric SIR.
[0018] In the figure:
[0019] 1. Top copper plating layer; 11. Asymmetric SIR; 12. Grounding metal hole; 2. Intermediate dielectric layer; 3. Bottom copper plating layer. Detailed implementation manners
[0020] In order to better understand the technical content of the utility model, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows. In this disclosure, aspects of the utility model are described with reference to the drawings, and many illustrative embodiments are shown in the drawings. The embodiments of this disclosure do not necessarily define all aspects of the utility model. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed in the utility model are not limited to any implementation manner. In addition, some aspects disclosed in the utility model can be used alone, or in any suitable combination with other aspects disclosed in the utility model.
[0021] Embodiment 1
[0022] As shown in Figures 1-5 , this is the first embodiment of the present utility model. This embodiment provides a band-pass filter with an asymmetric SIR, which includes a top copper plating layer 1, an intermediate dielectric layer 2, and a bottom copper plating layer 3. The intermediate dielectric layer 2 is disposed at the bottom of the top copper plating layer 1, and the bottom copper plating layer 3 is disposed at the bottom of the intermediate dielectric layer 2. The bottom copper plating layer 3 is a fully copper-plated layer grounded. The top copper plating layer 1 further includes an asymmetric SIR 11, a grounding metal hole 12, and input / output ports.
[0023] As shown in Figures 1-5 , in the case of achieving excellent performance, the circuit structure is simple, and it can be mass-produced using a simple printed circuit board process. Moreover, the processing accuracy can be well controlled, the yield is high, ensuring the advantage of low cost. The size of this filter is 10.4mm * 10.4mm, achieving a very small size, that is, the guided wavelength is 0.23λ * 0.23λ. Two transmission zeros are formed in the upper sideband of the filter through multi-path coupling and electromagnetic hybrid coupling, and high selectivity in the upper sideband of the excellent frequency and wide stopband suppression ability up to the 2.5th harmonic are achieved, with a small insertion loss of 0.55dB and excellent return loss of -20dB. Secondly, without affecting other technical indicators, only by changing the length of the low-impedance part of the SIR can the bandwidth of the filter be changed, enhancing the high adaptability of the filter to circuits with different bandwidths.
[0024] Embodiment 2
[0025] Referring to Figure 2 , this is the second embodiment of the present utility model. This embodiment is based on the previous embodiment.
[0026] In this embodiment, the number of grounding metal holes 12 is four, and the four grounding metal holes 12 are rotationally distributed at intervals of 90 degrees around the central grounding metal hole 12, showing central symmetry.
[0027] The number of input / output ports is two. The signals of the two input / output terminals are fifty ohms, and they are connected to the high-impedance lines of the two SIRs, and the input / output ports are distributed in a reverse central symmetry.
[0028] Embodiment 3
[0029] Referring to Figure 3 , this is the third embodiment of the present utility model. This embodiment is based on the previous two embodiments.
[0030] In this embodiment, the thicknesses of both the top copper plating layer 1 and the bottom copper plating layer 3 are 0.035mm, and the bottom copper plating layer 3 and the top copper plating layer 1 are respectively located on both sides of the intermediate dielectric layer 2.
[0031] The thickness of the bottom copper plating layer 3 is 0.254 mm, and the Rogers 5880 substrate is used.
[0032] When in use, first, the size of the filter is 10.4 mm * 10.4 mm, achieving a very small size, that is, the guided wavelength is 0.23λ * 0.23λ. Two transmission zeros are formed in the upper sideband of the filter through multipath coupling and electromagnetic hybrid coupling, and high selectivity in the upper sideband of the excellent frequency and wide stopband suppression ability up to the 2.5th harmonic are achieved, with a small insertion loss of 0.55 dB and excellent return loss of -20 dB. Secondly, without affecting other technical indicators, only by changing the length of the low-impedance part of the SIR can the bandwidth of the filter be changed, enhancing the high adaptability of the filter to different bandwidth circuits. Under the condition of achieving excellent performance, the circuit structure of this filter is simple, and it can be mass-produced by a simple printed circuit board process. Moreover, the processing accuracy can be well controlled, and the yield rate is high, ensuring the advantage of low cost.
[0033] The standard parts used in this application document can all be purchased from the market, and can also be customized according to the descriptions in the specification and the drawings. The specific connection methods of each part all adopt conventional means such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts, and equipment all adopt conventional models in the prior art. The control method is automatically controlled by a controller, and the control circuit of the controller can be realized by simple programming by those skilled in the art, which belongs to the common general knowledge in this field. And this application document is mainly used to protect the mechanical device, so the control method and circuit connection will not be explained in detail in this application document.
[0034] Although the present utility model has been disclosed above with preferred embodiments, it is not intended to limit the present utility model. Those with ordinary knowledge in the technical field to which the present utility model belongs can make various modifications and refinements without departing from the spirit and scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to what is defined by the claims.
Claims
1. A band-pass filter with an asymmetric SIR, comprising a top copper plating layer (1), an intermediate dielectric layer (2) and a bottom copper plating layer (3), characterized in that: The intermediate dielectric layer (2) is disposed at the bottom of the top copper plating layer (1), and the bottom copper plating layer (3) is disposed at the bottom of the intermediate dielectric layer (2). The bottom copper plating layer (3) is a fully copper-plated layer grounded. The top copper plating layer (1) further includes an asymmetric SIR (11), a ground via (12), and input / output ports.
2. The bandpass filter of the asymmetric SIR as claimed in claim 1, wherein: The number of the ground vias (12) is four, and the four ground vias (12) are rotationally distributed at intervals of 90 degrees around the central ground via (12), presenting central symmetry.
3. The bandpass filter of the asymmetric SIR according to claim 1, characterized in that: The number of the input / output ports is two. The signals of the two input / output terminals are 50 ohms and are connected to the high-impedance lines of two SIRs. The input / output ports are distributed in reverse central symmetry.
4. The bandpass filter of the asymmetric SIR according to claim 1, characterized in that: The thicknesses of both the top copper plating layer (1) and the bottom copper plating layer (3) are 0.035 mm, and the bottom copper plating layer (3) and the top copper plating layer (1) are respectively located on two sides of the intermediate dielectric layer (2).
5. The bandpass filter of the asymmetric SIR as claimed in claim 1, characterized in that: The thickness of the bottom copper plating layer (3) is 0.254 mm, and the Rogers 5880 substrate is used.