Filter power capacity improvement method and device, storage medium and filter element

Abstract

The application provides a filter power capacity improvement method, device, storage medium and filter element. The filter power capacity improvement method comprises the following steps: setting the port impedance of a bulk acoustic wave filter as a first impedance, so that the power density of a resonator in the bulk acoustic wave filter is less than or equal to a preset threshold value, wherein the first impedance is a complex impedance, and the impedance value of the first impedance is on a circle with a conductance equal to 1 in a Smith chart; determining an impedance transformation network connected to the port of the bulk acoustic wave filter according to the first impedance, the impedance transformation network being used to be connected to the bulk acoustic wave filter to form a connection body, and making the port impedance of the connection body a preset impedance value. The application has a good effect of improving the power capacity of the bulk acoustic wave filter.

Description

Technical Field

[0001] This invention relates to the field of filter technology, and in particular to a method, apparatus, storage medium, and filter element for improving filter power capacity. Background Technology

[0002] With the rapid development of wireless communication technology towards multi-band and multi-mode, higher requirements are being placed on radio frequency front-end devices, especially filters. For example, to improve communication quality and enhance user experience, filters need to have characteristics such as low insertion loss and high out-of-band rejection. Bulk acoustic wave (BAW) filters can perfectly meet these requirements. BAW filters are characterized by their small size, high roll-off, and low insertion loss, and filters based on this feature have been widely used in communication systems.

[0003] As mentioned above, bulk acoustic wave (BAW) filters have many advantages, but their disadvantages are also obvious, namely, their relatively small power capacity, typically around 1W on average. Currently, design methods have emerged to improve the power capacity of BAW filters. These methods generally involve splitting the resonator to reduce its power density, thereby increasing the filter's power capacity. Specifically, a single resonator is split into two resonators connected in series, increasing the resonator area and thus reducing its power density.

[0004] However, in the above design method, since the number of resonators increases after splitting, the number of resonator connection paths is undoubtedly increased, which worsens the insertion loss of the bulk acoustic wave filter, thus limiting the effect of improving power capacity. Summary of the Invention

[0005] In view of the above problems, this application provides a method, apparatus, storage medium and filtering element for improving filter power capacity, which has a better effect on improving filter power capacity.

[0006] To achieve the above objectives, the first aspect of this application provides a method for improving the power capacity of a filter, comprising: setting the port impedance of a bulk acoustic wave filter to a first impedance so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold, wherein the first impedance is a complex value impedance and the impedance value of the first impedance is on the circle with a conductance of 1 in the Smith admittance circle diagram.

[0007] The impedance transformation network connected to the port of the bulk acoustic wave filter is determined according to the first impedance. The impedance transformation network is used to connect with the bulk acoustic wave filter to form a connection body, and the port impedance of the connection body is set to a preset impedance value.

[0008] In one alternative implementation, the real part of the first impedance is less than a preset impedance value.

[0009] In one optional implementation, the port impedance of the bulk acoustic wave filter is set to a first impedance so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold, specifically including:

[0010] Determine the power density of each resonator in a bulk acoustic filter with a current port impedance, where the current port impedance is a complex value impedance;

[0011] If the power density of any resonator in each resonator is greater than or equal to a preset threshold, the current port impedance is continuously adjusted until the power density of each resonator in the bulk acoustic filter corresponding to the current port impedance is less than the preset threshold.

[0012] The current port impedance corresponding to the power density of each resonator being less than a preset threshold is determined as the first impedance, and the port impedance of the bulk acoustic wave filter is set as the first impedance.

[0013] In one optional implementation, determining the power density of each resonator in the bulk acoustic wave filter corresponding to the current port impedance specifically includes:

[0014] Determine the input power corresponding to the bulk acoustic wave filter with the current port impedance;

[0015] The power density of each resonator in the bulk acoustic filter is determined based on the input power.

[0016] In one alternative implementation, the current port impedance is continuously adjusted, specifically including:

[0017] Reduce the real part of the current port impedance by a preset step value.

[0018] In one optional implementation, the real part of the current port impedance is reduced by a preset step value, specifically including:

[0019] Reduce the real part of the current port impedance so that the reduced real part has a preset ratio to the original real part, wherein the impedance value of the first impedance is on the circle with a conductance of 1 in the Smith admittance circle diagram.

[0020] An impedance matching network consists of a matching element.

[0021] In one alternative implementation, the impedance transformation network includes a capacitor connected in parallel with the bulk acoustic wave filter; or, the impedance transformation network includes an inductor connected in parallel with the bulk acoustic wave filter.

[0022] A second aspect of this application provides a filter power capacity enhancement device, including a processor for executing the filter power capacity enhancement method described above.

[0023] A third aspect of this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the filter power capacity enhancement method described above.

[0024] A fourth aspect of this application provides a computer program product, including a computer program that, when executed by a processor, implements the filter power capacity enhancement method described above.

[0025] The fifth aspect of this application provides a filtering element, including a bulk acoustic wave filter and an impedance transformation network, wherein the input port and output port of the bulk acoustic wave filter are respectively connected to the corresponding impedance transformation network, and the port impedance of the bulk acoustic wave filter is a complex value impedance.

[0026] In one alternative implementation, the impedance transformation network includes an impedance circuit consisting of capacitors or inductors.

[0027] In one alternative implementation, the port impedance of the bulk acoustic wave filter is a+jb ohms, where b is a positive value.

[0028] The impedance transformation network includes a transformation capacitor, and the ports of the transformation capacitor and the bulk acoustic wave filter are connected in parallel.

[0029] In one alternative implementation, the port impedance of the bulk acoustic wave filter is a-jb ohms, where b is a positive value;

[0030] The impedance transformation network includes a transformation inductor, which is connected in parallel with the port of the bulk acoustic wave filter.

[0031] In one alternative implementation, the bulk acoustic wave filter includes multiple resonators, and the multiple resonators form at least one series branch connected between the input port and the output port of the bulk acoustic wave filter.

[0032] In one alternative implementation, the multiple resonators further form at least one parallel branch, one end of which is connected between two adjacent resonators on the series branch, and the other end is grounded.

[0033] The structure of the present invention, as well as its other inventive objects and beneficial effects, will become more apparent from the description of preferred embodiments taken in conjunction with the accompanying drawings. Attached Figure Description

[0034] Figure 1 This is a topology diagram of a filter element provided in an embodiment of this application;

[0035] Figure 2a This is a Smith admittance circle diagram of a filter element in the prior art;

[0036] Figure 2bA Smith admittance circle diagram of a filter element provided in an embodiment of this application;

[0037] Figure 3 A flowchart illustrating a method for improving the power capacity of a filter, provided in an embodiment of this application;

[0038] Figure 4 A flowchart illustrating the method for determining the port impedance of a bulk acoustic wave filter provided in this application embodiment;

[0039] Figure 5 This is a schematic diagram of another process for a filter power capacity enhancement method provided in an embodiment of this application;

[0040] Figure 6 This is a comparison diagram of the transmission curves of the filter power capacity enhancement method of this application and the method of the prior art;

[0041] Figure 7 This is a schematic diagram of a filter power capacity enhancement device provided in an embodiment of this application.

[0042] Explanation of reference numerals in the attached figures:

[0043] 100-bulk acoustic wave filter;

[0044] 200-Filter power capacity enhancement device;

[0045] 201 - First impedance transformation network;

[0046] 202 - Second impedance transformation network;

[0047] 203 - Memory;

[0048] 204 - Processor;

[0049] 205-bus;

[0050] M - Input port;

[0051] N - Output port;

[0052] Q and P ports. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0054] Bulk acoustic wave (BAW) filters utilize the piezoelectric effect of piezoelectric crystals to generate resonance. Since the resonance is generated by mechanical waves, rather than electromagnetic waves, and the wavelength of mechanical waves is much shorter than that of electromagnetic waves, the size of BAW resonators and the filters they form is significantly smaller than that of traditional electromagnetic filters. Furthermore, because the crystal orientation growth of piezoelectric crystals can now be well controlled, the resonators have extremely low losses and high quality factors, thus enabling them to meet complex design requirements such as steep transition bands and low insertion losses. However, BAW filters have relatively low power capacity. To increase their power capacity, current technologies generally reduce the resonator power density by splitting the resonator, thereby increasing the filter's power capacity. However, this method leads to an increased number of resonators after splitting, worsening the filter's insertion loss, which is detrimental to improving power capacity.

[0055] In this embodiment, by changing the port impedance, the power density can be reduced and the power capacity increased without splitting the resonator, while keeping the filter performance unchanged. At the same time, the matching circuit can also be simplified.

[0056] The following description, in conjunction with the accompanying drawings, illustrates the filtering elements and the method for increasing the power capacity of the filter according to embodiments of this application.

[0057] Figure 1 This is a topology diagram of a filter element provided in an embodiment of this application.

[0058] Reference Figure 1 The filtering element of this application includes a bulk acoustic wave filter 100 and an impedance transformation network. The input port M and output port N of the bulk acoustic wave filter 100 are respectively connected to the corresponding impedance transformation network. The port impedance of the bulk acoustic wave filter 100 is a complex value impedance, and the impedance value of the first impedance lies on the circle with a conductance of 1 in the Smith admittance circle diagram. It should be noted that in the embodiments of this application, the port impedance of the bulk acoustic wave filter 100 refers to the impedance at the input port M or the impedance at the output port N.

[0059] In the above scheme, the port impedance of the bulk acoustic wave filter 100 is set to a complex value, which reduces the power density of the resonator and increases the power capacity. Unlike existing technologies, this application does not require splitting the resonator and does not suffer from increased filter insertion loss, thus maintaining the filter performance unchanged.

[0060] On the other hand, the above scheme also connects the input port M and output port N of the bulk acoustic wave filter 100 to the corresponding impedance transformation network. By selecting an appropriate value for the impedance transformation network, the impedance of the entire filtering element can be matched to a preset impedance value. It should be noted that, precisely because the port impedance of the bulk acoustic wave filter 100 is a complex value, each port of the bulk acoustic wave filter 100 only needs one matching element as an impedance transformation network to match the impedance of the filtering element to a preset impedance value, such as 50 ohms. This method simplifies the impedance transformation network and is beneficial for the miniaturization and standardization of the filtering element.

[0061] Optionally, the impedance transformation network may include a first impedance transformation network 201 and a second impedance transformation network 202. One end of the first impedance transformation network 201 is connected to port P of the filter element, and the other end is connected to a port of the bulk acoustic wave filter 100, such as the input port M of the bulk acoustic wave filter 100. One end of the second impedance transformation network 202 is connected to port Q of the filter element, and the other end is connected to a port of the bulk acoustic wave filter 100, such as the output port N of the bulk acoustic wave filter 100. In other words, the bulk acoustic wave filter 100 is connected in series between the first impedance transformation network 201 and the second impedance transformation network 202; the first impedance transformation network 201 is connected in series between port P and the input port M of the bulk acoustic wave filter 100; and the second impedance transformation network 202 is connected in series between port Q and the output port N of the bulk acoustic wave filter 100.

[0062] Optionally, the impedance transformation network may consist of only one matching element. For example, the impedance matching network may include an impedance circuit composed of a capacitor or an inductor. This simplifies the structure of the impedance transformation network.

[0063] The port impedance of the bulk acoustic wave filter 100 is a complex value impedance, which can be set to a+jb ohms or a-jb ohms, where b is a positive value.

[0064] Specifically, as an optional implementation, the port impedance of the bulk acoustic wave filter 100 is a+jb ohms, and the impedance transformation network may include a transformation capacitor, which is connected in parallel with the port of the bulk acoustic wave filter 100.

[0065] As another optional implementation, the port impedance of the bulk acoustic wave filter 100 is a-jb ohms, and the impedance transformation network may include a transformation inductor connected in parallel with the port of the bulk acoustic wave filter 100.

[0066] Figure 2a This is a Smith admittance circle diagram of a filter element in the prior art. Figure 2b The Smith admittance circle diagram of a filter element provided in an embodiment of this application.

[0067] Optionally, the port impedance of the bulk acoustic wave filter also needs to be set to a+jb or a-jb. Figure 2b The Smith admittance circle diagram shown is on the circle where g=1, where g is the conductance. When g=1, the circle of equal conductance passes through the point.

[0068] Specifically, refer to Figure 2a , 2b Point O is a preset impedance value, such as 50 ohms. Point A is a real impedance value, point B is the impedance value of a+jb, and point C is the impedance value of a-jb.

[0069] If the port impedance of the bulk acoustic wave filter 100 is less than the preset impedance value, for example, less than 50 ohms, an impedance transformation network can be set at each end of the bulk acoustic wave filter 100 to transform the two port impedances of the filter element to 50 ohms.

[0070] If the port impedance of the bulk acoustic wave filter 100 is a real number, then... Figure 2a At point A in the diagram, if the port impedance of the bulk acoustic wave filter 100 is to be matched from point A to point O, there are two possible paths. The first path is from point A to point B, and then from point B to point O, which means connecting an inductor in series with the bulk acoustic wave filter 100 and then a capacitor in parallel. The second path is from point A to point C, and then from point C to point O, which means connecting a capacitor in series and then an inductor in parallel. In both of these matching methods, each port of the bulk acoustic wave filter 100 requires two matching elements, which is not conducive to the miniaturization of the impedance transformation network.

[0071] In this embodiment of the application, as mentioned above, the port impedance of the bulk acoustic wave filter 100, for example, the port impedance at the input port M, is a complex value impedance, i.e., a+jb ohms or a-jb ohms.

[0072] When the port impedance of the bulk acoustic wave filter 100 is a+jb ohms, the corresponding Figure 2b Point B in the diagram represents the port impedance of the bulk acoustic wave filter 100, which is matched from point B to point O. Since the matching path is from point B to point O, the impedance transformation network can be made to include a capacitor; that is, the first impedance transformation network 201 is an impedance circuit composed of capacitors. Specifically, this can be achieved by connecting a capacitor in parallel with the bulk acoustic wave filter 100.

[0073] Similarly, when the port impedance of the bulk acoustic wave filter 100 is a-jb ohms, the corresponding Figure 2bPoint C in the diagram represents the port impedance of the bulk acoustic wave filter 100, which is matched from point C to point O; that is, the matching path is from point C to point O. It is advisable to include an inductor in the impedance transformation network; the first impedance transformation network 201 is an impedance circuit composed of inductors. Specifically, this can be achieved by connecting an inductor in parallel with the bulk acoustic wave filter 100.

[0074] It is understandable that this explanation takes the interaction between the input port M of the bulk acoustic wave filter 100 and the first impedance transformation network 201 to match the port impedance of the filter element to a preset impedance value as an example. The interaction between the output port N of the bulk acoustic wave filter 100 and the second impedance transformation network 202 is similar to the interaction between the input port M and the first impedance transformation network 201, and will not be described again here.

[0075] In this way, each port of the solid acoustic wave filter 100 only needs one matching element as an impedance transformation network to match the impedance of the filter element to a preset impedance value, such as 50 ohms. This method simplifies the impedance transformation network and is conducive to the miniaturization and standardization of filter elements.

[0076] Continue to refer to Figure 1 In this embodiment of the application, the bulk acoustic wave filter 100 includes multiple filter units. Here, the filter unit can be a resonator, and a filter unit can also form a complete filter.

[0077] The aforementioned multiple filter units can form at least one series branch, which is connected between the input port M and the output port N of the bulk acoustic wave filter 100.

[0078] Multiple filter units also form at least one parallel branch, with one end of the parallel branch connected between two adjacent filter units on the series branch and the other end grounded.

[0079] Specifically, corresponding to Figure 2b At point B or C, the filter element has a 4-3 topology, meaning it consists of one series branch and three parallel branches. The series branch is composed of four filter units, such as resonators S21, S22, S23, and S24, connected in series between the input port M and the output port N. The three parallel branches are connected at one end to the adjacent series resonators and at the other end to ground. Specifically, the first parallel branch consists of resonator P21 and inductor L21, the second parallel branch consists of resonator P22 and inductor L22, and the third parallel branch consists of resonator P23 and inductor L23. It is important to note that the parallel resonators P21, P22, and P23 require a mass load so that their resonant frequencies are lower than the resonant frequencies of the series resonators.

[0080] Generally, the impedance value of each resonator can be calculated by 1 / ωc, where ω is the frequency and c is the equivalent capacitance of the resonator. The impedance value 1 / ωc of the resonator is generally proportional to the real part 'a' of the port impedance (a+jb ohms or a-jb) of the bulk acoustic wave filter 100. In the filter element of this application, 'a' can be reduced, which increases the equivalent capacitance of the resonator, meaning the equivalent area of ​​the resonator needs to be increased. With the input power remaining constant, the power density of the bulk acoustic wave resonator can be reduced. Therefore, the power density of the resonator can be further reduced without splitting the resonator, thereby improving the power capacity of the filter element. In other words, this filter element sets the port impedance of the bulk acoustic wave filter 100 to a complex number, further increasing the equivalent area of ​​the bulk acoustic wave filter 100, thereby reducing the power density and increasing the power capacity of the filter.

[0081] However, the port impedance of the bulk acoustic wave filter will decrease accordingly, which may prevent it from reaching the specified value, such as the commonly used 50 ohms in the industry. To avoid this situation, as mentioned earlier, impedance transformation networks are connected to the input and output terminals of the bulk acoustic wave filter, so that the port impedance of the entire filter element, i.e., the bulk acoustic wave filter and the impedance transformation networks at both ends, can be increased to the specified value.

[0082] The method for improving the power capacity of the filter in this application is described below with reference to the accompanying drawings. Figure 3 This is a flowchart illustrating a method for improving the power capacity of a filter, as provided in an embodiment of this application.

[0083] Reference Figure 3 The filter power capacity enhancement method of this application includes:

[0084] S10. Set the port impedance of the bulk acoustic wave filter to the first impedance so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold, wherein the first impedance is a complex value impedance.

[0085] S20. Determine the impedance transformation network connected to the port of the bulk acoustic wave filter according to the first impedance. The impedance transformation network is used to connect with the bulk acoustic wave filter to form a connection body, and the port impedance of the connection body is a preset impedance value.

[0086] In the above scheme, the port impedance of the bulk acoustic wave filter is set to a complex value, which can make the power density of the resonator less than or equal to a preset threshold, thereby reducing the power density of the resonator and increasing the power capacity. This application does not require splitting the resonator as in existing technologies and does not suffer from increased filter insertion loss, thus maintaining the filter performance unchanged.

[0087] On the other hand, the above scheme also determines an impedance transformation network to match the bulk acoustic wave filter based on the complex impedance, so as to match the impedance of the entire connector to a preset impedance value. Specifically, since the port impedance of the bulk acoustic wave filter is complex, only one matching element is needed at each port of the bulk acoustic wave filter to match the impedance of the connector to a preset impedance value, such as 50 ohms. This method simplifies the impedance transformation network and is beneficial for filter miniaturization and standardization.

[0088] The preset threshold can be 6W / mm. 2 The power density of the resonator in the bulk acoustic wave filter is less than or equal to 6 W / mm². 2 At that time, the power capacity of the bulk acoustic wave filter can meet the requirements. The impedance transformation network connected to the port of the bulk acoustic wave filter is determined according to the first impedance. Specifically, the port impedance of the filter element, i.e., the connecting body, is a preset impedance value. When the first impedance value is also determined, the specific form of the impedance transformation network and the value of the components can be determined by the Smith chart.

[0089] The connecting body is the aforementioned filtering element. The filtering element can be a series connection, for example, an impedance transformation network can be connected in series with a bulk acoustic filter to form a series connection. However, the filtering element in this application is not limited to this, and the connection method between the impedance transformation network and the bulk acoustic filter can also be selected as needed.

[0090] In this embodiment, the real part of the first impedance is less than a preset impedance value, for example, less than 50 ohms.

[0091] Figure 4 This is a flowchart illustrating the method for determining the port impedance of a bulk acoustic wave filter provided in an embodiment of this application.

[0092] Reference Figure 4 Optionally, the port impedance of the bulk acoustic wave filter can be set to a first impedance so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold, specifically including:

[0093] S11. Determine the power density of each resonator in the bulk acoustic wave filter with the current port impedance, where the current port impedance is a complex value impedance.

[0094] S12. If the power density of any resonator in each resonator is greater than or equal to the preset threshold, the current port impedance is continuously adjusted until the power density of each resonator in the bulk acoustic filter corresponding to the current port impedance is less than the preset threshold.

[0095] S13. Determine the current port impedance corresponding to the power density of each resonator being less than a preset threshold as the first impedance, and set the port impedance of the bulk acoustic wave filter as the first impedance.

[0096] In this embodiment, making the power density of the resonators in the bulk acoustic wave filter less than or equal to a preset threshold means that the power density of each resonator in the bulk acoustic wave filter is less than or equal to the preset threshold. Specifically, the power density of each resonator in the bulk acoustic wave filter can be calculated, and the resonators with the highest power density can be identified (3-5 can be selected depending on the actual situation). Their power densities are compared to see if they are less than the preset threshold. If they are less than the preset threshold, the impedance transformation network can be designed.

[0097] If the power density of any resonator is greater than or equal to a preset threshold, the power density of that resonator can be reduced by continuously adjusting the current port impedance. At the same time, the power density of each resonator is calculated until it is determined that the power density of each resonator in the bulk acoustic filter corresponding to the current port impedance is less than the preset threshold. Then, the impedance transformation network can be designed.

[0098] Optionally, determine the power density of each resonator in the bulk acoustic wave filter corresponding to the current port impedance, specifically including:

[0099] Determine the input power corresponding to the current port impedance of the bulk acoustic wave filter, and then determine the power density of each resonator in the bulk acoustic wave filter based on the input power. In other words, the power density of each resonator in the bulk acoustic wave filter is calculated based on the input power of the bulk acoustic wave filter.

[0100] In the above scheme, the current port impedance is continuously adjusted, which can specifically include reducing the real part of the current port impedance by a preset step value. When the current port impedance decreases, the resonator area increases, thus reducing the power density of the resonator. Reducing the real part of the current port impedance by a preset step value means that the reduction in the real part of the current port impedance is a fixed value each time.

[0101] In this embodiment of the application, as an optional implementation, reducing the real part of the current port impedance by a preset step value specifically includes:

[0102] The real part of the current port impedance is reduced so that the reduced real part is proportional to the original real part, where the first impedance value lies on the circle in the Smith admittance diagram where conductance equals 1. For example, the real part of the port impedance can be reduced to 70% of its original value to reduce the power density of each resonator. Here, the imaginary part of the current port impedance also needs to be changed accordingly, but it must be ensured that the port impedance after the real part is reduced still lies on the circle in the Smith admittance diagram where conductance equals 1.

[0103] Figure 5 This is a schematic diagram of another process for the filter power capacity enhancement method provided in an embodiment of this application. (Refer to...) Figure 5 The method of this application will be illustrated with a specific example. First, the port impedance of the bulk acoustic wave filter is set to a+jb or a-jb ohms (a<50, b is a positive value), and the filter topology is established. It is required that the port impedance a+jb or a-jb of the bulk acoustic wave filter lies on the circle g=1 of the Smith admittance circle diagram.

[0104] At this point, based on the input power of the bulk acoustic wave filter, calculate the power density of each resonator included in the bulk acoustic wave filter, and identify the resonators with the highest power density (3-5 can be selected depending on the actual situation). Compare whether their power density is less than 6W / mm². 2 If the value is less than this, an impedance transformation network can be designed, i.e., a capacitor or inductor can be connected in parallel at the port of the bulk acoustic wave filter. If the value is greater than or equal to this, the real part 'a' of the port impedance of the bulk acoustic wave filter can be reduced to 70% of its original value, where the port impedance value lies on the circle with conductance equal to 1 in the Smith admittance circle diagram. Then, the above process is repeated until the power density of each resonator is less than 6 W / mm². 2 Then, the impedance transformation network is designed.

[0105] To verify the effectiveness of the filter power capacity enhancement method in the embodiments of this application, the applicant designed a bandpass filter with a 4-3 topology and a frequency coverage range of 2.575GHz-2.635GHz.

[0106] Figure 6 This is a comparison of the transmission curves of the filter power capacity enhancement method of this application and the method of the prior art. It should be noted that in this method, the impedance of the filter element is a preset impedance value, i.e., 50 ohms. The solid line is the transmission curve of the method of this patent, and the dashed line is the transmission curve of the prior art method. Figure 6 As can be seen, the curves of the two methods match well. This indicates that the method in this application can achieve filter performance that is roughly the same as that of existing methods.

[0107] The power density of the two is compared below. When the input power of the bulk acoustic wave filter is 2W, the frequency point on the right side of the filter element is the frequency of interest. Therefore, the simulation frequency point is selected as 2.635GHz.

[0108] Table 1 compares the power density of the method used in this application and the prior art. As can be seen from Table 1, the power density of each resonator in the method of this application is less than 6 W / mm². 2 The bulk acoustic wave filter has a large power capacity. In existing methods, the power density of each resonator is greater than 6 W / mm². 2 The power capacity of the bulk acoustic wave filter is relatively small.

[0109] Table 1: Power Density Comparison Table between the Method of this Application and the Methods of the Prior Art

[0110]

[0111] Figure 7 This is a schematic diagram of a filter power capacity enhancement device provided in an embodiment of this application. Based on the above, another embodiment of the present invention provides a filter power capacity enhancement device 200, see reference... Figure 7 The device 200 may include a memory 203 and at least one processor 204.

[0112] The memory 203 stores computer-executed instructions, and at least one processor 204 executes the computer-executed instructions stored in the memory 203, causing the at least one processor 204 to execute the filter power capacity enhancement method as described above.

[0113] The memory 203 and the processor 204 are connected via a bus 205.

[0114] Based on the above, one embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by processor 204, implement the filter power capacity enhancement method as described above.

[0115] The computer-readable storage medium can be ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0116] Based on the above, one embodiment of the present invention provides a computer program product, including a computer program that, when executed by a processor 204, implements the filter power capacity enhancement method as described above.

[0117] In the several embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0118] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0119] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The unit composed of the above modules can be implemented in hardware or in the form of hardware plus software functional units.

[0120] The integrated modules described above, implemented as software functional modules, can be stored in a computer-readable storage medium. These software functional modules, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods described in the various embodiments of the present invention.

[0121] It should be understood that the aforementioned processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly manifested as being executed by a hardware processor, or executed by a combination of hardware and software modules within the processor.

[0122] The memory may include high-speed RAM, and may also include non-volatile storage (NVM), such as at least one disk storage device, and may also be a USB flash drive, external hard drive, read-only memory, disk or optical disc, etc.

[0123] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the bus in this invention is not limited to a single bus or a single type of bus.

[0124] The aforementioned storage medium can be implemented from any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium can be any available medium accessible to general-purpose or special-purpose computers.

[0125] An exemplary storage medium is coupled to a processor, enabling control to read information from and write information to the storage medium. Of course, the storage medium can also be an integral part of the control system. The processor and storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and storage medium can exist as discrete components within an electronic device or a main control device.

[0126] In this embodiment, a method for improving the power capacity of a filter includes: setting the port impedance of a bulk acoustic wave (SAW) filter to a first impedance so that the power density of the resonator in the SAW filter is less than or equal to a preset threshold, wherein the first impedance is a complex-valued impedance; determining an impedance transformation network connected to the port of the SAW filter based on the first impedance, the impedance transformation network being used to connect with the SAW filter to form a connection body, and setting the port impedance of the connection body to a preset impedance value. In the above scheme, setting the port impedance of the SAW filter to a complex-valued impedance allows the power density of the resonator to be less than or equal to a preset threshold, thereby reducing the power density of the resonator and improving the power capacity. This application does not require splitting the resonator as in the prior art and does not have the problem of increased filter insertion loss, thus maintaining the filter performance unchanged. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "connection" should be interpreted broadly. For example, it can refer to a fixed connection or an indirect connection through an intermediate medium, or it can refer to the internal connection of two components or the interaction relationship between two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0127] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0128] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein.

[0129] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the power capacity of a filter, characterized in that, include: The port impedance of the bulk acoustic wave filter is set as a first impedance so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold. The first impedance is a complex value impedance and the impedance value of the first impedance is on the circle with a conductance of 1 in the Smith admittance circle diagram. The impedance transformation network to which the port of the bulk acoustic wave filter is connected is determined based on the first impedance. The impedance transformation network is used to connect with the bulk acoustic wave filter to form a connector, and the port impedance of the connector is set to a preset impedance value. The impedance transformation network is composed of a matching element.

2. The method according to claim 1, characterized in that, The real part of the first impedance is less than the preset impedance value.

3. The method according to claim 1, characterized in that, Setting the port impedance of the bulk acoustic wave filter to a first impedance, so that the power density of the resonator in the bulk acoustic wave filter is less than or equal to a preset threshold, specifically includes: Determine the power density of each resonator in the bulk acoustic filter with a current port impedance, wherein the current port impedance is a complex value impedance; If the power density of any of the resonators is greater than or equal to a preset threshold, the current port impedance is continuously adjusted until the power density of each resonator in the bulk acoustic filter corresponding to the current port impedance is less than the preset threshold. The current port impedance corresponding to the power density of each resonator being less than the preset threshold is determined as the first impedance, and the port impedance of the bulk acoustic wave filter is set as the first impedance.

4. The method according to claim 3, characterized in that, Determining the power density of each resonator in the bulk acoustic filter corresponding to the current port impedance specifically includes: Determine the input power corresponding to the bulk acoustic filter with respect to the current port impedance; The power density of each resonator in the bulk acoustic filter is determined based on the input power.

5. The method according to claim 3, characterized in that, The continuous adjustment of the current port impedance specifically includes: The real part of the current port impedance is reduced by a preset step value.

6. The method according to claim 5, characterized in that, The step of reducing the real part of the current port impedance by a preset step value specifically includes: The real part of the current port impedance is reduced so that the reduced real part has a preset ratio to the original real part, wherein the impedance value of the first impedance lies on the circle with a conductance of 1 in the Smith admittance circle diagram.

7. The method according to claim 1, characterized in that, The impedance transformation network includes a capacitor connected in parallel with the bulk acoustic wave filter; or, the impedance transformation network includes an inductor connected in parallel with the bulk acoustic wave filter.

8. A filter power capacity enhancement device, characterized in that, Includes a processor for performing the filter power capacity enhancement method according to any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by the processor, implement the filter power capacity enhancement method as described in any one of claims 1-7.

10. A filter element, characterized in that, The filter includes a bulk acoustic wave filter and an impedance transformation network. The input and output ports of the bulk acoustic wave filter are respectively connected to the corresponding impedance transformation network. The port impedance of the bulk acoustic wave filter is a complex value impedance. The impedance transformation network is composed of a matching element. The filter element improves the filter power capacity using the filter power capacity improvement method according to any one of claims 1-7.

11. The filtering element according to claim 10, characterized in that, The impedance transformation network includes an impedance circuit composed of capacitors or inductors.

12. The filtering element according to claim 11, characterized in that, The port impedance of the bulk acoustic wave filter is a+jb ohms, where b is a positive value; The impedance transformation network includes a transformation capacitor, which is connected in parallel with the port of the bulk acoustic wave filter.

13. The filtering element according to claim 11, characterized in that, The port impedance of the bulk acoustic wave filter is a-jb ohms, where b is a positive value; The impedance transformation network includes a transformation inductor, which is connected in parallel with the port of the bulk acoustic wave filter.

14. The filter element according to any one of claims 10-13, characterized in that, The bulk acoustic wave filter includes multiple filter units, and the multiple filter units form at least one series branch, which is connected between the input port and the output port of the bulk acoustic wave filter.

15. The filtering element according to claim 14, characterized in that, The plurality of filter units also form at least one parallel branch, one end of which is connected between two adjacent filter units on the series branch, and the other end is grounded.

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