CN114567287A - Multiplexer - Google Patents
Multiplexer Download PDFInfo
- Publication number
- CN114567287A CN114567287A CN202210277719.4A CN202210277719A CN114567287A CN 114567287 A CN114567287 A CN 114567287A CN 202210277719 A CN202210277719 A CN 202210277719A CN 114567287 A CN114567287 A CN 114567287A
- Authority
- CN
- China
- Prior art keywords
- coupling coefficient
- electromechanical coupling
- filter
- multiplexer
- series resonant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000008878 coupling Effects 0.000 claims abstract description 150
- 238000010168 coupling process Methods 0.000 claims abstract description 150
- 238000005859 coupling reaction Methods 0.000 claims abstract description 150
- 239000000463 material Substances 0.000 claims description 25
- 230000005540 biological transmission Effects 0.000 claims description 20
- 230000001939 inductive effect Effects 0.000 claims description 5
- 235000019687 Lamb Nutrition 0.000 claims description 3
- 239000007787 solid Substances 0.000 claims description 3
- 239000010409 thin film Substances 0.000 claims description 3
- 238000003780 insertion Methods 0.000 abstract description 12
- 230000037431 insertion Effects 0.000 abstract description 12
- 238000002955 isolation Methods 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 239000003990 capacitor Substances 0.000 description 6
- 229910052715 tantalum Inorganic materials 0.000 description 3
- 239000002033 PVDF binder Substances 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000026683 transduction Effects 0.000 description 2
- 238000010361 transduction Methods 0.000 description 2
- 229910052726 zirconium Inorganic materials 0.000 description 2
- 229910052691 Erbium Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 229910052984 zinc sulfide Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
- H03H9/703—Networks using bulk acoustic wave devices
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/70—Multiple-port networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source
- H03H9/72—Networks using surface acoustic waves
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The present disclosure provides a multiplexer. The multiplexer according to this disclosure includes: at least one transmitting filter and at least one receiving filter coupled in common to an antenna node, the transmitting filter and the receiving filter each including a series resonant cell and a parallel resonant cell, wherein an electromechanical coupling coefficient of the series and parallel resonant cells of the transmitting filter is higher than an electromechanical coupling coefficient of the series and parallel resonant cells of the receiving filter, or an electromechanical coupling coefficient of at least one series resonant cell of the transmitting filter and an electromechanical coupling coefficient of a parallel resonant cell of the receiving filter are higher than an electromechanical coupling coefficient of a series resonant cell of the receiving filter. According to the present disclosure, a multiplexer having a high insertion loss and a high isolation can be realized without adding additional components or manufacturing process steps.
Description
Technical Field
The present disclosure relates to the field of electronic circuit technology, and more particularly, to a multiplexer.
Background
With the development of wireless communication applications, people have higher and higher requirements on data transmission rate, and the data transmission rate corresponds to high utilization rate of spectrum resources and complexity of spectrum. The complexity of the communication protocol imposes stringent requirements on the various performances of the rf system, and the multiplexers play a crucial role in the rf front-end module. With the increase of 5G commercial products, the demand for multiplexers such as B1, B2, B3, B5, B7, and B8 is increasing.
At present, multiplexers based on acoustic resonators have been increasingly widely used due to their advantages of steep edge roll-off (roll-off) characteristics, high selectivity, high power capacity, and strong anti-electrostatic discharge (ESD) capability.
The acoustic resonators used in the transmit (Tx) filter and the receive (Rx) filter in current multiplexers typically employ the same type of piezoelectric material, e.g., AlN or AlN doped with other elements, such that the acoustic resonators have the same or similar electromechanical coupling coefficients. However, the electromechanical coupling coefficient of the acoustic resonator using AlN as a piezoelectric material is insufficient, and the requirements of high insertion loss of the Tx filter (low-frequency filter) in the multiplexer and high isolation to the Rx band cannot be satisfied. Further, although the electromechanical coupling coefficient of the acoustic resonator using AlN doped as a piezoelectric material is improved, the series resonance frequency of the parallel resonance unit of the Rx filter (high-frequency filter) in the multiplexer falls within the Tx band (low-frequency band), so that a recess is easily generated within the Tx passband.
In order to solve the above problem, in the prior art, an impedance matching tuning unit is generally added to improve isolation while ensuring high insertion loss, or an inductor or a capacitor is connected in parallel in a series resonant unit connected to an antenna node. However, these improvements increase the design difficulty, increase the integration difficulty, and are not easy to miniaturize the multiplexer.
Therefore, there is still a need in the art for a multiplexer that can achieve high insertion loss and high isolation without adding additional components or manufacturing process steps.
Disclosure of Invention
The following presents a simplified summary of the disclosure in order to provide a basic understanding of some aspects of the disclosure. It should be understood, however, that this summary is not an exhaustive overview of the disclosure, nor is it intended to identify key or critical elements of the disclosure, nor is it intended to be used to limit the scope of the disclosure. This summary is provided merely for the purpose of presenting some of the inventive concepts related to the disclosure in a simplified form as a prelude to the more detailed description that is presented later.
An object of the present disclosure is to provide a multiplexer capable of achieving high insertion loss and high isolation without adding additional components or manufacturing process steps.
According to an aspect of the present disclosure, there is provided a multiplexer including: at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and at least one reception filter whose input node is coupled to the antenna node and which includes a series resonant cell and a parallel resonant cell, wherein the series resonant cell and the parallel resonant cell of the transmission filter have substantially the same first electromechanical coupling coefficient, and the series resonant cell and the parallel resonant cell of the reception filter have substantially the same second electromechanical coupling coefficient, wherein the first electromechanical coupling coefficient is higher than the second electromechanical coupling coefficient.
According to an embodiment of the present disclosure, a difference of the first electromechanical coupling coefficient and the second electromechanical coupling coefficient is greater than one tenth of the first electromechanical coupling coefficient.
According to an embodiment of the present disclosure, the first electromechanical coupling coefficient is in a range of 7% to 20%, and the second electromechanical coupling coefficient is in a range of 5% to 15%. Preferably, the first electromechanical coupling coefficient is in the range of 7.5% to 8.5% and the second electromechanical coupling coefficient is in the range of 5% to 6.8%.
According to another aspect of the present disclosure, there is provided a multiplexer including: at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and at least one receiving filter, an input node of which is coupled to the antenna node, and which includes a series resonant cell and a parallel resonant cell, wherein at least one series resonant cell of the transmitting filter has a third electromechanical coupling coefficient, and the series resonant cell and the parallel resonant cell of the receiving filter have substantially the same fourth electromechanical coupling coefficient, and the third electromechanical coupling coefficient is higher than the fourth electromechanical coupling coefficient.
According to an embodiment of the present disclosure, a difference of the third electromechanical coupling coefficient and the fourth electromechanical coupling coefficient is greater than one tenth of the third electromechanical coupling coefficient.
According to an embodiment of the present disclosure, the at least one series resonant cell of the transmit filter having the third electromechanical coupling coefficient is directly coupled to the output node of the transmit filter.
According to an embodiment of the present disclosure, the series resonant unit and the parallel resonant unit of the transmission filter other than the at least one series resonant unit having the third electromechanical coupling coefficient have substantially the same fifth electromechanical coupling coefficient.
According to another aspect of the present disclosure, there is provided a multiplexer including: at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and at least one reception filter whose input node is coupled to the antenna node and which includes series resonant cells and parallel resonant cells, wherein at least one of the series resonant cells of the transmission filter has a sixth electromechanical coupling coefficient, the series resonant cells of the reception filter have substantially the same seventh electromechanical coupling coefficient, and the parallel resonant cells of the reception filter have substantially the same eighth electromechanical coupling coefficient, and the sixth and eighth electromechanical coupling coefficients are higher than the seventh electromechanical coupling coefficient.
According to an embodiment of the present disclosure, a difference of the sixth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the sixth electromechanical coupling coefficient, and a difference of the eighth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the eighth electromechanical coupling coefficient.
According to an embodiment of the present disclosure, the at least one series resonant cell of the transmit filter having the sixth electromechanical coupling coefficient is directly coupled to the output node of the transmit filter.
According to an embodiment of the present disclosure, the series resonant unit and the parallel resonant unit of the transmission filter other than the at least one series resonant unit having the sixth electromechanical coupling coefficient have substantially the same ninth electromechanical coupling coefficient.
According to an embodiment of the present disclosure, the series resonance unit and the parallel resonance unit of the transmission filter and/or the reception filter are connected in a ladder configuration.
According to an embodiment of the present disclosure, for each of the transmission filter and the reception filter, the series resonant unit is connected in series between an input node and an output node of the corresponding filter, and the parallel resonant unit is connected in parallel between a connection node, which is a node at an input and/or an output of the series resonant unit, and a ground node.
According to an embodiment of the present disclosure, a parallel resonance unit includes a resonator and an inductor connected in series between a connection node and a ground node.
According to an embodiment of the present disclosure, the series resonance unit and/or the parallel resonance unit of the transmission filter and/or the reception filter comprises a resonator, which is a surface acoustic resonator, a thin film bulk acoustic resonator, a solid state assembly acoustic resonator, or a lamb wave resonator.
According to the embodiment of the present disclosure, the electromechanical coupling coefficient is adjusted by changing the piezoelectric material of the resonator or adjusting the doping element, doping concentration, and/or doping combination of the piezoelectric material of the resonator.
According to an embodiment of the present disclosure, the electromechanical coupling coefficient is adjusted by changing the type of the resonator.
According to an embodiment of the present disclosure, a part of the series resonance unit and/or the parallel resonance unit of the transmission filter and/or the reception filter includes a resonance unit composed of a capacitive element and an inductive element.
Drawings
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated into and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
Fig. 1 illustrates an equivalent circuit diagram of a duplexer according to an embodiment of the present disclosure.
Detailed Description
In the present specification, it will also be understood that when an element is referred to as being "on," "connected to" or "coupled to" another element relative to the other element, such as on, connected to or coupled to the other element, the one element can be directly provided on, connected to or coupled directly to the one element, or intervening third elements may also be present. In contrast, when an element is referred to in this specification as being "directly on," "directly connected to," or "directly coupled to" other elements, relative to the other elements, there are no intervening elements provided therebetween.
The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Like numbers refer to like elements throughout. Also, in the drawings, the thickness, ratio and size of the components are exaggerated for clarity of illustration.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, "a," "an," "the," and "at least one" do not denote a limitation of quantity, but rather are intended to include both the singular and the plural, unless the context clearly indicates otherwise. For example, "an element" means the same as "at least one element" unless the context clearly dictates otherwise. "at least one of" should not be construed as limited to the quantity "one". "or" means "and/or". The term "and/or" includes any and all combinations of at least one of the associated listed items.
Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms defined in commonly used dictionaries should be interpreted as having the same meaning as is in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The meaning of "comprising" or "comprises" indicates the property, quantity, step, operation, element, component or combination thereof, but does not exclude other properties, quantities, steps, operations, elements, components or combination thereof.
Hereinafter, exemplary embodiments according to the present disclosure will be described with reference to the accompanying drawings.
Fig. 1 shows an equivalent circuit diagram of a duplexer 100 according to an embodiment of the present disclosure. Those skilled in the art will recognize that references herein to a "multiplexer" include duplexers, triplexers, quadplexers, and the like, as well as numerous types of devices. Therefore, although the multiplexer of the present disclosure is described as a duplexer in fig. 1, a person skilled in the art can easily extend the multiplexer to other types such as a triplexer, a quadplexer, and the like based on the duplexer shown in fig. 1. In view of these expansion techniques, which are known to those skilled in the art, the details thereof are not described in greater detail herein for the sake of brevity.
As shown in fig. 1, the duplexer 100 may include a transmit (Tx) filter 110 and a receive (Rx) filter 120.
As described above, duplexer 100 can be easily extended to other types of multiplexers such as triplexers, quadroplexers, etc. by adding more Tx filters and/or Rx filters, all of which are intended to be within the scope of the present disclosure.
As shown in fig. 1, the output node NTxout of the Tx filter 110 is coupled to the antenna node Nt, and includes a series resonant cell and a parallel resonant cell connected in a ladder configuration. As shown in fig. 1, an inductor Lt as an impedance matching unit may be connected to the antenna node Nt.
Those skilled in the art will recognize that although the Tx filter 110 is a 3-ladder filter including the first to third series resonant cells S1101 to S1103 and the first to third parallel resonant cells P1101 to P1103 in fig. 1, the present disclosure is not limited thereto. According to embodiments of the present disclosure, Tx filter 110 may be a ladder filter of any order or a filter having other topologies and may include any number of series resonant cells and parallel resonant cells, all of which variations are intended to be within the scope of the present disclosure.
As shown in fig. 1, the first to third series resonant units S1101 to S1103 are sequentially connected in series between the output node NTxout and the input node NTxin of the Tx filter 110. Further, an output impedance matching unit (not shown) may be further connected in series and/or parallel between the output node NTxout and the first series resonance unit S1101, and an output impedance matching unit (not shown) may be further connected in series and/or parallel between the third series resonance unit S1103 and the input node NTxin. The input impedance matching unit and the output impedance matching unit may include impedance matching elements such as an inductor, a capacitor, a resonator, and the like, or a matching unit composed of them in common.
Further, as shown in fig. 1, the first to third parallel resonant units P1101 to P1103 are connected in parallel between connection nodes N1101 to N1103 and a ground node GND, the connection nodes N1101 to N1103 being nodes at the input and/or output ends of the first to third series resonant units S1101 to S1103.
Further, as shown in fig. 1, the input node NRxin of the Rx filter 120 is coupled to the antenna node Nt, and includes a series resonant unit and a parallel resonant unit connected in a ladder configuration.
Those skilled in the art will recognize that although the Rx filter 120 is a 3-ladder filter including the first to third series resonant units S1201 to S1203 and the first to third parallel resonant units P1201 to P1203 in fig. 1, the present disclosure is not limited thereto. According to the embodiment of the present disclosure, the Rx filter 120 may be a ladder filter of any order or a filter having other topologies and may include any number of series resonant cells and parallel resonant cells, and all such variations are intended to be within the scope of the present disclosure.
Furthermore, although in fig. 1 the Rx filter 120 has the same circuit topology as the Tx filter 110, i.e., each is a 3-step filter, the present disclosure is not limited thereto. According to an embodiment of the present disclosure, the Rx filter 120 may have a different circuit topology from the Tx filter 110, i.e., may be a ladder filter of other orders than 3 orders or a filter having other circuit topologies, and all such variations are intended to be within the scope of the present disclosure.
As shown in fig. 1, the first to third series resonant units S1201 to S1203 are sequentially connected in series between an input node NRxin and an output node NRxout of the Rx filter 120. Further, an input impedance matching unit (not shown) may be further connected in series and/or parallel between the input node NRxin and the first series resonance unit S1201, and an output impedance matching unit (not shown) may be further connected in series and/or parallel between the third series resonance unit S1203 and the output node NRxout. The input impedance matching unit and the output impedance matching unit may include impedance matching elements such as an inductor, a capacitor, a resonator, etc., or matching units composed of them in common.
Further, as shown in fig. 1, the first to third parallel resonant units P1201 to P1203 are connected in parallel between connection nodes N1201 to N1203 and a ground node GND, the connection nodes N1201 to N1203 being nodes at the input and/or output ends of the first to third series resonant units S1201 to S1203.
Further, those skilled in the art will recognize that although the Tx filter 110 and the Rx filter 120 according to the embodiments of the present disclosure are described herein using a ladder filter as an example, the present disclosure is not limited thereto. One skilled in the art can readily envision applying the inventive concepts of the present disclosure to multiplexers based on other filter circuit topologies besides ladder filters in light of the teachings of the present disclosure.
The first to third series resonance units S1101 to S1103 and the first to third parallel resonance units P1101 to P1103 of the Tx filter 110 and the first to third series resonance units S1201 to S1203 and the first to third parallel resonance units P1201 to P1203 of the Rx filter 120 may be collectively referred to as "resonance units" herein. It will be appreciated by those skilled in the art that the "resonant cell" referred to herein may be constituted by a single resonator or by a series and/or parallel circuit of a resonator and an inductor and/or capacitor. For example, each of the first to third parallel resonant units P1101 to P1103 of the Tx filter 110 and the first to third parallel resonant units P1201 to P1203 of the Rx filter 120 may be composed of a resonator and an inductor connected in series between the connection node and the ground node. Furthermore, it will be appreciated by those skilled in the art that the term "resonant unit" as used herein may also include resonant units consisting of capacitive elements, such as capacitors, and inductive elements, such as inductors. All such variations are intended to be within the scope of the present disclosure.
Accordingly, it will be understood by those skilled in the art that the electromechanical coupling coefficients of the resonant cells recited herein may be considered as the electromechanical coupling coefficients of the resonators comprised by the resonant cells. In other words, the "electromechanical coupling coefficient of the resonance unit" and the "electromechanical coupling coefficient of the resonator" have the same technical meaning herein.
According to an embodiment of the present disclosure, the resonators constituting each resonance unit of the Tx filter 110 and the Rx filter 120 may be acoustic resonators, such as surface acoustic resonators, thin film bulk acoustic resonators, solid mount body acoustic resonators, or lamb wave resonators. Acoustic resonators typically have a sandwich structure of a lower electrode, a piezoelectric layer and an upper electrode fabricated on a substrate, wherein the piezoelectric layer is made of a piezoelectric material with electromechanical transduction capability, such as AlN or doped AlN, for effecting transduction between acoustic signals (acoustic waves) and electrical signals. Piezoelectric material and optimum FOM of acoustic resonator using the same2Determined in conjunction with a quality factor Q, i.e. FOM-kt2Q, wherein the electromechanical coupling coefficient characterizes the coupling and conversion capability between the acoustic energy and the electric energy of the piezoelectric material, and the value is in direct proportion to the bandwidth of the working frequency band. Since acoustic resonators are known to the person skilled in the art, they are not elaborated here for the sake of brevitySection(s) are described in more detail.
The inventive concept of the present disclosure is to implement a multiplexer having a high insertion loss and a high isolation without adding additional components or manufacturing process steps by adjusting an electromechanical coupling coefficient of each resonance unit of a Tx filter and an Rx filter included in the multiplexer.
According to the first embodiment of the present disclosure, the first to third series resonant units S1101 to S1103 and the first to third parallel resonant units P1101 to P1103 of the Tx filter 110 have substantially the same first electromechanical coupling coefficient, and the first to third series resonant units S1201 to S1203 and the first to third parallel resonant units P1201 to P1203 of the Rx filter 120 have substantially the same second electromechanical coupling coefficient, wherein the first electromechanical coupling coefficient is higher than the second electromechanical coupling coefficient. It should be noted that "substantially the same" as referred to herein means that the difference in value between the two is within a reasonable margin of error, preferably within 5% relative error.
According to a first embodiment of the present disclosure, the difference between the first electromechanical coupling coefficient and the second electromechanical coupling coefficient is greater than one tenth of the first electromechanical coupling coefficient.
According to a first embodiment of the present disclosure, the first electromechanical coupling coefficient is in the range of 7% to 20%, and the second electromechanical coupling coefficient is in the range of 5% to 15%. Preferably, the first electromechanical coupling coefficient is in the range of 7.5% to 8.5% and the second electromechanical coupling coefficient is in the range of 5% to 6.8%.
According to the embodiments of the present disclosure, a larger first electromechanical coupling coefficient may improve the insertion loss of the Tx filter and may reduce the inductance value of the series inductor required for the parallel resonant unit; meanwhile, the smaller second electromechanical coupling coefficient can reduce the influence of the parallel resonant cells of the Rx filter on the insertion loss of the Tx filter. Therefore, setting the first electromechanical coupling coefficient higher than the second electromechanical coupling coefficient can achieve the technical effect of improving the insertion loss and the isolation.
According to the second embodiment of the present disclosure, at least one of the first to third series resonant units S1101 to S1103 of the Tx filter 110 has a third electromechanical coupling coefficient, and the first to third series resonant units S1201 to S1203 and the first to third parallel resonant units P1201 to P1203 of the Rx filter 120 have substantially the same fourth electromechanical coupling coefficient, wherein the third electromechanical coupling coefficient is higher than the fourth electromechanical coupling coefficient.
According to a second embodiment of the present disclosure, the difference between the third electromechanical coupling coefficient and the fourth electromechanical coupling coefficient is greater than one tenth of the third electromechanical coupling coefficient.
Further, according to the second embodiment of the present disclosure, the at least one series resonant cell of the Tx filter 110 having the third electromechanical coupling coefficient is the first series resonant cell S1101, i.e., the series resonant cell directly coupled to the output node NTxout of the Tx filter 110.
According to the second embodiment of the present disclosure, the Tx filter 110 having the series resonant unit (e.g., the first series resonant unit S1101) having a large electromechanical coupling coefficient may contribute to an increase in insertion loss at high frequencies of the Tx filter 110 and the Rx filter 120.
Further, according to the second embodiment of the present disclosure, the second and third series resonant units S1102 and S1103 and the first to third parallel resonant units P1101 to P1103 of the Tx filter 110 except for at least one series resonant unit, i.e., the first series resonant unit S1101, have substantially the same fifth electromechanical coupling coefficient.
According to the third embodiment of the present disclosure, at least one of the first to third series resonant units S1101 to S1103 of the Tx filter 110 has a sixth electromechanical coupling coefficient, the first to third series resonant units S1201 to S1203 of the Rx filter 120 have substantially the same seventh electromechanical coupling coefficient, and the first to third parallel resonant units P1201 to P1203 of the Rx filter 120 have substantially the same eighth electromechanical coupling coefficient, wherein the sixth and eighth electromechanical coupling coefficients are higher than the seventh electromechanical coupling coefficient.
According to a third embodiment of the present disclosure, a difference of the sixth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the sixth electromechanical coupling coefficient, and a difference of the eighth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the eighth electromechanical coupling coefficient.
Further, according to the third embodiment of the present disclosure, at least one series resonant cell of the Tx filter 110 having the sixth electromechanical coupling coefficient is the first series resonant cell S1101, i.e., the series resonant cell directly coupled to the output node NTxout of the Tx filter 110.
According to the third embodiment of the present disclosure, the Tx filter 110 having the series resonant unit (e.g., the first series resonant unit S1101) having a large electromechanical coupling coefficient may contribute to an increase in insertion loss at high frequencies of the Tx filter 110 and the Rx filter 120.
Further, according to the third embodiment of the present disclosure, the second and third series resonant units S1102 and S1103 and the first to third parallel resonant units P1101 to P1103 of the Tx filter 110 except for at least one series resonant unit, i.e., the first series resonant unit S1101, have substantially the same ninth electromechanical coupling coefficient.
According to the above embodiments of the present disclosure, the first, third, sixth, and eighth electromechanical coupling coefficients may be regarded as high electromechanical coupling coefficients, and the second, fourth, fifth, seventh, and ninth electromechanical coupling coefficients may be regarded as low electromechanical coupling coefficients. According to an embodiment of the present disclosure, the high electromechanical coupling coefficient is in the range of 7% to 20%, and the low electromechanical coupling coefficient is in the range of 5% to 15%. Preferably, the high electromechanical coupling coefficient is in the range of 7.5% to 8.5% and the low electromechanical coupling coefficient is in the range of 5% to 6.8%.
According to an embodiment of the present disclosure, the resonance units of the Tx filter 110 and the Rx filter 120 may be constituted by resonators. According to the embodiment of the present disclosure, the electromechanical coupling coefficient is adjusted by changing the piezoelectric material of the resonator or adjusting the doping element, doping concentration, and/or doping combination of the piezoelectric material of the resonator.
According to embodiments of the present disclosure, the piezoelectric material of the resonator may include, but is not limited to: wurtzite structures, such as AlN, ZnO; perovskite structures, e.g. BaTiO3、Pb(Ti,Zr)O3、Li(Nb,Ta)O3Or (K, Na) NbO3(ii) a And organic piezoelectric materials such as polyvinylidene fluoride PVDF and the like.
According to the embodiment of the present disclosure, the resonator of each resonance unit may have different types of piezoelectric materials, and the adjustment of the electromechanical coupling coefficient may be achieved by changing the piezoelectric material of the resonator. For example, to obtain a high electromechanical coupling coefficient, Li (Nb, Ta) O may be used3As the piezoelectric material, and in order to obtain a low electromechanical coupling coefficient, AlN may be used as the piezoelectric material.
Alternatively or in combination, the resonators of the respective resonance units may also have the same type of piezoelectric material according to embodiments of the present disclosure. It should be noted that the "same type of piezoelectric material" referred to herein refers to a piezoelectric material in which the host is the same, for example AlN or AlN doped with another element may be considered herein as the same type of piezoelectric material. According to the embodiment of the disclosure, the adjustment of the electromechanical coupling coefficient can be realized by adjusting the doping element, the doping concentration and/or the doping combination of the piezoelectric material of the resonator.
As a specific example, if it is desired to obtain a resonator having a low electromechanical coupling coefficient, the piezoelectric material may employ pure AlN, AlN having a low doping concentration, or AlN doped with an element for reducing the electromechanical coupling coefficient. According to embodiments of the present disclosure, doping elements for reducing the electromechanical coupling coefficient include, but are not limited to B, Ga and In.
Further, as a specific example, if it is desired to obtain a resonator having a high electromechanical coupling coefficient, the piezoelectric material may employ AlN having a high doping concentration, AlN doped with an element for increasing the electromechanical coupling coefficient, or a stack having a plurality of doped AlN layers having different doping concentrations. According to embodiments of the present disclosure, doping elements for increasing the electromechanical coupling coefficient include, but are not limited to, Ti, Sc, Mg, Zr, Hf, Sb, Y, Sm, Eu, Er, Ta, and Cr.
According to the embodiment of the present disclosure, the adjustment of the electromechanical coupling coefficient may also be achieved by adjusting the type of the resonator. For example, to obtain a high electromechanical coupling coefficient, a surface acoustic resonator may be used, and to obtain a low electromechanical coupling coefficient, a bulk acoustic resonator may be used.
According to an embodiment of the present disclosure, some of the resonance units of the Tx filter 110 and the Rx filter 120 may further include a resonance unit composed of a capacitive element, e.g., a capacitor, and an inductive element, e.g., an inductor. According to the embodiments of the present disclosure, the adjustment of the electromechanical coupling coefficient may also be achieved by adjusting the parameters of the capacitive element and the inductive element constituting the resonance unit.
According to the embodiments of the present disclosure, a multiplexer having a high insertion loss and a high isolation can be implemented without adding additional components or manufacturing process steps.
Although the present disclosure has been described with reference to exemplary embodiments thereof, those skilled in the art will appreciate that various modifications and changes may be made without departing from the spirit and scope of the present disclosure as set forth in the claims.
Claims (18)
1. A multiplexer, comprising:
at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and
at least one receive filter having an input node coupled to the antenna node and comprising a series resonant cell and a parallel resonant cell,
wherein the series resonant cell and the parallel resonant cell of the transmit filter have substantially the same first electromechanical coupling coefficient, and the series resonant cell and the parallel resonant cell of the receive filter have substantially the same second electromechanical coupling coefficient, an
Wherein the first electromechanical coupling coefficient is higher than the second electromechanical coupling coefficient.
2. The multiplexer according to claim 1, wherein the multiplexer is configured to,
wherein a difference between the first electromechanical coupling coefficient and the second electromechanical coupling coefficient is greater than one tenth of the first electromechanical coupling coefficient.
3. The multiplexer according to claim 1, wherein the multiplexer is configured to,
wherein the first electromechanical coupling coefficient is in a range of 7% to 20% and the second electromechanical coupling coefficient is in a range of 5% to 15%.
4. A multiplexer, comprising:
at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and
at least one receive filter having an input node coupled to the antenna node and including a series resonant cell and a parallel resonant cell,
wherein at least one series resonant cell of the transmit filter has a third electromechanical coupling coefficient and the series resonant cell and the parallel resonant cell of the receive filter have substantially the same fourth electromechanical coupling coefficient, an
Wherein the third electromechanical coupling coefficient is higher than the fourth electromechanical coupling coefficient.
5. The multiplexer according to claim 4, wherein the multiplexer is configured to,
wherein a difference between the third electromechanical coupling coefficient and the fourth electromechanical coupling coefficient is greater than one tenth of the third electromechanical coupling coefficient.
6. The multiplexer according to claim 4, wherein the multiplexer is configured to,
wherein at least one series resonant cell of the transmit filter having the third electromechanical coupling coefficient is directly coupled to an output node of the transmit filter.
7. The multiplexer according to claim 4, wherein the multiplexer is configured to,
wherein the series resonant cells and the parallel resonant cells of the transmission filter other than the at least one series resonant cell having the third electromechanical coupling coefficient have substantially the same fifth electromechanical coupling coefficient.
8. A multiplexer, comprising:
at least one transmission filter having an output node coupled to the antenna node and including a series resonant unit and a parallel resonant unit; and
at least one receive filter having an input node coupled to the antenna node and including a series resonant cell and a parallel resonant cell,
wherein at least one series resonant cell of the transmit filter has a sixth electromechanical coupling coefficient, the series resonant cells of the receive filter have substantially the same seventh electromechanical coupling coefficient, and the parallel resonant cells of the receive filter have substantially the same eighth electromechanical coupling coefficient, an
Wherein the sixth electromechanical coupling coefficient and the eighth electromechanical coupling coefficient are higher than the seventh electromechanical coupling coefficient.
9. The multiplexer of claim 8, wherein the multiplexer is configured to,
wherein a difference of the sixth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the sixth electromechanical coupling coefficient, and a difference of the eighth electromechanical coupling coefficient and the seventh electromechanical coupling coefficient is greater than one tenth of the eighth electromechanical coupling coefficient.
10. The multiplexer according to claim 8, wherein the multiplexer is configured to,
wherein the at least one series resonant cell of the transmit filter having the sixth electromechanical coupling coefficient is directly coupled to an output node of the transmit filter.
11. The multiplexer according to claim 8, wherein the multiplexer is configured to,
wherein the series resonant cells and the parallel resonant cells of the transmission filter other than the at least one series resonant cell having the sixth electromechanical coupling coefficient have substantially the same ninth electromechanical coupling coefficient.
12. The multiplexer of any one of claims 1-11,
wherein the series resonant cells and the parallel resonant cells of the transmit filter and/or the receive filter are connected in a ladder configuration.
13. The multiplexer of any one of claims 1 to 11,
wherein, for each of the transmit filter and the receive filter,
the series resonant cells are connected in series between the input node and the output node of the respective filters, an
The parallel resonant cell is connected in parallel between a connection node, which is a node at the input and/or output of the series resonant cell, and a ground node.
14. The multiplexer of any one of claims 1-11,
the parallel resonance unit includes a resonator and an inductor connected in series between the connection node and the ground node.
15. The multiplexer of any one of claims 1 to 11,
wherein the series resonance unit and/or the parallel resonance unit of the transmission filter and/or the reception filter comprise resonators, and the resonators are surface acoustic resonators, thin film bulk acoustic resonators, solid assembly body acoustic resonators, or lamb wave resonators.
16. The multiplexer according to claim 15, wherein the multiplexer is configured to,
wherein the electromechanical coupling coefficient is adjusted by changing the piezoelectric material of the resonator or adjusting the doping element, doping concentration and/or doping combination of the piezoelectric material of the resonator.
17. The multiplexer according to claim 15, wherein the multiplexer is configured to,
wherein the electromechanical coupling coefficient is adjusted by changing the type of the resonator.
18. The multiplexer of any one of claims 1 to 11,
wherein a part of the series resonance unit and/or the parallel resonance unit of the transmission filter and/or the reception filter includes a resonance unit composed of a capacitive element and an inductive element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210277719.4A CN114567287A (en) | 2022-03-21 | 2022-03-21 | Multiplexer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210277719.4A CN114567287A (en) | 2022-03-21 | 2022-03-21 | Multiplexer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114567287A true CN114567287A (en) | 2022-05-31 |
Family
ID=81720392
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210277719.4A Pending CN114567287A (en) | 2022-03-21 | 2022-03-21 | Multiplexer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114567287A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020153965A1 (en) * | 2001-04-23 | 2002-10-24 | Ruby Richard C. | Controlled effective coupling coefficients for film bulk acoustic resonators |
| US20120218052A1 (en) * | 2010-02-22 | 2012-08-30 | Tetsuya Tsurunari | Antenna sharing device |
| US20130127565A1 (en) * | 2011-11-22 | 2013-05-23 | Taiyo Yuden Co., Ltd. | Duplexer |
| US20200343875A1 (en) * | 2018-06-01 | 2020-10-29 | Akoustis, Inc. | Effective coupling coefficients for strained single crystal epitaxial film bulk acoustic resonators |
| CN112073028A (en) * | 2020-08-24 | 2020-12-11 | 诺思(天津)微系统有限责任公司 | Filter out-of-band rejection optimization method, filter, multiplexer and communication equipment |
| CN112997404A (en) * | 2018-06-01 | 2021-06-18 | 阿库斯蒂斯有限公司 | Improvement of effective coupling coefficient of strained single crystal epitaxial film bulk acoustic resonator |
| CN113328714A (en) * | 2021-06-16 | 2021-08-31 | 苏州汉天下电子有限公司 | Piezoelectric structure, method of manufacturing the same, and piezoelectric resonator including the same |
-
2022
- 2022-03-21 CN CN202210277719.4A patent/CN114567287A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020153965A1 (en) * | 2001-04-23 | 2002-10-24 | Ruby Richard C. | Controlled effective coupling coefficients for film bulk acoustic resonators |
| US20120218052A1 (en) * | 2010-02-22 | 2012-08-30 | Tetsuya Tsurunari | Antenna sharing device |
| US20130127565A1 (en) * | 2011-11-22 | 2013-05-23 | Taiyo Yuden Co., Ltd. | Duplexer |
| CN103138032A (en) * | 2011-11-22 | 2013-06-05 | 太阳诱电株式会社 | Duplexer |
| US20200343875A1 (en) * | 2018-06-01 | 2020-10-29 | Akoustis, Inc. | Effective coupling coefficients for strained single crystal epitaxial film bulk acoustic resonators |
| CN112997404A (en) * | 2018-06-01 | 2021-06-18 | 阿库斯蒂斯有限公司 | Improvement of effective coupling coefficient of strained single crystal epitaxial film bulk acoustic resonator |
| CN112073028A (en) * | 2020-08-24 | 2020-12-11 | 诺思(天津)微系统有限责任公司 | Filter out-of-band rejection optimization method, filter, multiplexer and communication equipment |
| CN113328714A (en) * | 2021-06-16 | 2021-08-31 | 苏州汉天下电子有限公司 | Piezoelectric structure, method of manufacturing the same, and piezoelectric resonator including the same |
Non-Patent Citations (2)
| Title |
|---|
| H. NAKAMURA, H. NAKANISHI, T. TSURUNARI, J. FUJIWARA, Y. HAMAOKA, R. GOTO: "Small-sized SAW duplexer on non-flat SiO2/Al/LiNbO3 structure for UMTS Band I system", 2010 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM, 13 July 2020 (2020-07-13), pages 1464 - 1467 * |
| 汤亮;郝震宏;乔东海;: "2.4GHz射频薄膜体声波谐振器的研制", 功能材料与器件学报, no. 01, 25 February 2009 (2009-02-25), pages 29 - 35 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8902020B2 (en) | Resonator filter with multiple cross-couplings | |
| US8063717B2 (en) | Duplexer having resonator filters | |
| US11057018B2 (en) | Acoustically coupled resonator notch and bandpass filters | |
| US11050412B2 (en) | Acoustic filter using acoustic coupling | |
| US7515018B2 (en) | Acoustic resonator | |
| US8674789B2 (en) | Serially connected first and second coupled resonator filters configured to provide at least one feedback capacitor | |
| US8576024B2 (en) | Electro-acoustic filter | |
| CN111327288B (en) | Bulk acoustic wave resonator, ultra-narrow band filter, duplexer and multiplexer | |
| US7646265B2 (en) | BAW resonator filter bandwidth and out-of-band frequency rejection | |
| US7518410B2 (en) | Duplexer | |
| US20010052739A1 (en) | Bulk acoustic wave device | |
| JP2006513662A (en) | Resonator filter structure with equal resonant frequency | |
| JP2006513662A5 (en) | ||
| US20220337223A1 (en) | Hybrid resonators | |
| CN115622529A (en) | Filter and multiplexer including same | |
| CN116346069B (en) | Filter and electronic device | |
| CN114567287A (en) | Multiplexer | |
| CN108449067B (en) | Bulk acoustic wave filter | |
| CN217721150U (en) | Multiplexer for improving second harmonic suppression | |
| CN107508019B (en) | Duplexer | |
| US11575363B2 (en) | Hybrid bulk acoustic wave filter | |
| CN114710136A (en) | Filter, duplexer and multiplexer | |
| CN116232367A (en) | Extractor and communication equipment comprising same | |
| US20070182508A1 (en) | Band pass filter and duplexer having the same | |
| Detaint et al. | New materials and new devices for filtering in radio-communication systems |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |