WO2021104505A1 - 滤波电路、双工器、通信装置 - Google Patents

滤波电路、双工器、通信装置 Download PDF

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Publication number
WO2021104505A1
WO2021104505A1 PCT/CN2020/132536 CN2020132536W WO2021104505A1 WO 2021104505 A1 WO2021104505 A1 WO 2021104505A1 CN 2020132536 W CN2020132536 W CN 2020132536W WO 2021104505 A1 WO2021104505 A1 WO 2021104505A1
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Prior art keywords
parallel resonator
parallel
series
filter circuit
resonator unit
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PCT/CN2020/132536
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English (en)
French (fr)
Inventor
古健
王为标
刘止愚
唐清悟
张磊
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华为技术有限公司
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Priority to JP2022531599A priority Critical patent/JP2023503678A/ja
Priority to EP20894019.7A priority patent/EP4057507A4/en
Publication of WO2021104505A1 publication Critical patent/WO2021104505A1/zh

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
    • H03H9/56—Monolithic crystal filters
    • H03H9/566—Electric coupling means therefor
    • H03H9/568—Electric coupling means therefor consisting of a ladder configuration
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
    • H03H9/542—Filters comprising resonators of piezoelectric or electrostrictive material including passive elements
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/64—Filters using surface acoustic waves
    • H03H9/6423—Means for obtaining a particular transfer characteristic
    • H03H9/6433—Coupled resonator filters
    • H03H9/6483—Ladder SAW filters
    • 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
    • H03H9/706—Duplexers
    • 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
    • H03H9/725—Duplexers

Definitions

  • the embodiments of the application relate to the technical field of wireless radio frequency communication, and in particular to a filter circuit, a duplexer, and a communication device
  • the quality of wireless signals is used as one of the important parameters of the communication devices to measure the overall quality of the communication devices.
  • the transmission and reception of the wireless signal in the communication device require the use of a filter to perform filtering processing. Therefore, the filter has a greater impact on the quality of the wireless signal.
  • the passive intermodulation interference (PIM) between the filters in each wireless signal channel is relatively large, causing the wireless radio frequency signals transmitted in each channel to have Large passive intermodulation interference noise, which in turn affects the overall quality of the communication device.
  • an embodiment of the present application provides a filter circuit, a duplexer, and a communication device.
  • an embodiment of the present application provides a filter circuit, which includes an input terminal, a series resonator unit, a parallel resonance unit, and an output terminal.
  • the input terminal is used to receive radio frequency signals
  • the one series resonator unit is connected between the input terminal and the output terminal, and the series resonator unit and the parallel resonator unit cooperate with each other for the The radio frequency signal is output from the output terminal after filtering.
  • the parallel resonator unit includes M parallel resonator branches connected in parallel with each other, and the M parallel resonator branches are all connected between a first node between the input terminal and the output terminal and a ground terminal, And each parallel resonator branch of the M parallel resonator paths includes at least one parallel resonator, and the parallel resonator unit is the parallel resonator unit that is one level closest to the output end, and M is greater than Or a natural number equal to 2.
  • Each parallel resonator includes a first electrode of a first polarity and a second electrode of a second polarity, wherein the electrode connected to the first node in each of the parallel resonator branches is the first electrode Or, the electrode connected to the first node in each parallel resonator branch is a second electrode of the second polarity.
  • the PIM3 in the passive intermodulation can be improved and the interference generated by the filter circuit as a whole can be effectively suppressed, ensuring In view of the filtered quality of the radio frequency signal, and the polarity of the electrodes of the parallel resonator connected to the first node in the two parallel resonant branches is the same, the parallel resonant branch is easier to set up.
  • the interference can be effectively suppressed by setting a parallel resonator unit at the first node, thereby effectively reducing the overall volume of the filter circuit.
  • each of the parallel resonator branches includes two or more resonators
  • the two or more parallel resonators are connected in series with each other. Since the parallel resonator is continuously arranged in series, the connection method of the parallel resonator is easier.
  • each of the parallel resonator branches includes two or three resonators
  • the number of parallel resonators in the parallel resonator unit and the interference suppression capability can reach an optimal balance point, That is, at this time, the interference suppression of the filter circuit is better and the overall volume of the filter circuit is small due to the small number of parallel resonators.
  • the number of parallel resonators connected in series in each parallel resonator branch is different, and the interference suppression of the filter circuit is adjusted by adjusting the number of parallel resonators in each parallel resonator branch.
  • the series resonator unit presents a high impedance characteristic at an anti-resonant frequency
  • the parallel resonator unit presents a high impedance characteristic at a resonant frequency
  • the series resonator unit and the parallel resonator The units constitute a band-pass filter, and the center frequency of the band-pass filter is the resonance frequency of the series resonator unit or the anti-resonance frequency of the parallel resonator unit.
  • the series resonator unit and the parallel resonator unit cooperate with each other, so that the filter circuit can effectively suppress interference while filtering the received radio frequency signal.
  • the filter circuit may be a surface acoustic wave filter or may be a bulk acoustic wave filter, so as to perform filtering processing with lower interference for signals transmitted in the form of surface acoustic wave or bulk acoustic wave, respectively.
  • the embodiments of the present application provide a duplexer with better passive intermodulation, which includes the two aforementioned filters, and the two filters are directed against the radio frequency in the radio frequency signal receiving direction and the radio frequency signal sending direction, respectively.
  • the signal is filtered, so that when both the transmitting direction and the receiving direction are filtered for the radio frequency signal, the interference is better suppressed and the passive intermodulation is better.
  • an embodiment of the present application provides a communication device that includes at least the aforementioned filter circuit, and the filter circuit can better suppress interference during filtering processing of radio frequency signals in the transmit frequency band or the receive frequency band, and prevent interference The source intermodulation is better, so that the quality of the signal transmitted in the communication device is better.
  • the communication device further includes an antenna connected to the filter circuit, and the antenna is used to receive the radio frequency signal to be filtered by the filter circuit and transmit the radio frequency signal filtered by the filter circuit.
  • Figure 1 is a functional block diagram of a radio frequency communication module
  • Figure 2 is a functional block diagram of a duplexer in an embodiment of the application
  • FIG. 3 is a schematic structural diagram of a communication device applied to the radio frequency communication module shown in FIG. 1 in an embodiment of the application;
  • FIG. 4 is a schematic structural diagram of a communication device applied to the radio frequency communication module shown in FIG. 1 in an embodiment of the application;
  • FIG. 5 is a schematic diagram of the circuit structure of the filter shown in FIG. 1 in an embodiment of the application;
  • Figure 6 is a schematic diagram of the RF signal waveform in the operating characteristics of the sub-series resonator unit
  • Fig. 7 is a schematic diagram of a radio frequency signal waveform in the operating characteristics of the first parallel resonator unit
  • Fig. 8 is a schematic diagram of a radio frequency signal waveform in the working characteristics of the filter shown in Fig. 4;
  • FIG. 9 is a schematic diagram of the circuit structure of the filter shown in FIG. 1 in another embodiment of the application.
  • FIG. 10 is a schematic diagram of the circuit structure of the filter shown in FIG. 1 in another embodiment of the application;
  • FIG. 11 is a schematic diagram of the circuit structure of the filter shown in FIG. 1 in another embodiment of the application.
  • the radio frequency communication module 10 includes a filter circuit 100, an antenna 101 and a signal amplifier 103.
  • the filter circuit 100 is connected to the antenna 101 and the signal amplifier 103.
  • the connection described in this embodiment is an electrical connection through a conductive line and the transmission of electrical signals can be performed.
  • the antenna 101 is used to transmit wireless signals to other communication devices according to different frequencies, or to receive wireless signals from other communication devices.
  • the filter circuit 100 is used to feed signals from the signal amplifier 103 to the antenna 101 in the transmitting frequency band, or in other embodiments of the present application, the filter circuit 100 can also be applied in the receiving frequency band, from the antenna 20 to the signal The amplifier 103 feeds the signal.
  • the filter circuit 100 can suppress various frequencies in the receiving frequency band or the transmitting frequency band, that is, filtering the radio frequency signal in the receiving frequency band.
  • the filter circuit 100 is applied to a filter or the filter circuit 100 is a filter to perform filtering processing on radio frequency signals in the receiving frequency band or the transmitting frequency band.
  • FIG. 1 only shows one signal amplifier 103, but the signal amplifier 103 may include a low-noise amplifier for processing the receiving frequency band and a power amplifier for the transmitting frequency band, and the number of amplifier stages and the number of inter-stage filters can be based on Set the actual situation.
  • the filter circuit 100 filters the radio frequency signal for a single channel, that is, the filter circuit 100 filters the radio frequency signal in the transmitting frequency band alone, or filters the video signal in the receiving frequency band alone. .
  • two filter circuits 100 constitute a duplexer 100a for dual-channel filtering.
  • three or more filter circuits may also be used.
  • 100 constitutes a multi-channel multiplexer.
  • two filter circuits 100 in the duplexer 100a receive radio frequency signals in different directions and then perform filter processing.
  • one of the filter circuits 100 is designed to be transmitted to the transmission frequency band ( The RF signal in TX) is filtered, and then another filter circuit 100 filters the RF signal in the receiving frequency band (RX) provided from the antenna 101.
  • the duplexer 100 also includes a functional circuit (not shown) for separating the transmitting frequency band and the receiving frequency band.
  • the circuit structure of the two filters 100 is basically the same.
  • the filter circuit 100 can reduce the interference in the radio frequency signal of the transmitting frequency band or the radio frequency signal of the receiving frequency band .
  • the filter circuit 100 may be applied to a surface acoustic wave filter (Surface Acoustic Wave, SAW). In other embodiments of the present application, the filter circuit 100 may also be applied to a bulk acoustic wave filter (Bulk Acoustic Wave, BAW). )in.
  • SAW Surface Acoustic Wave
  • BAW Bulk Acoustic Wave
  • FIG. 3 is a schematic structural diagram of a communication device 1 to which the radio frequency communication module 10 shown in FIG. 1 is applied in an embodiment of the application.
  • the communication device 1 is a network device, and the network device includes a base station (BS), and the base station includes the radio frequency communication module 10 shown in FIG. 1.
  • a base station may be a device that is deployed in a wireless access network and can communicate with a terminal wirelessly.
  • the base station may have many forms, such as macro base stations, micro base stations, relay stations, and access points.
  • the base station involved in the embodiment of the present application may be a base station in 5G or a base station in LTE, where the base station in 5G may also be referred to as a transmission reception point (TRP) or gNB.
  • TRP transmission reception point
  • the device used to implement the function of the network device may be a network device; it may also be a device capable of supporting the network device to implement the function, such as a chip system, and the device may be installed in the network device.
  • FIG. 4 is a schematic structural diagram of a communication device 1 to which the radio frequency communication module 10 shown in FIG. 1 is applied in an embodiment of the application.
  • the communication device 1 may be a mobile communication device, such as a mobile phone, a tablet computer, etc., where the mobile communication device may include the radio frequency communication module 10 shown in FIG. 1.
  • FIG. 5 is a schematic diagram of the circuit structure of the filter circuit 100 shown in FIG. 1 in an embodiment of the application.
  • the filter circuit 100 includes an input terminal In, an inductor L, a series resonance unit 110, a parallel resonance unit 120, and an output terminal Out.
  • the input terminal In is connected to the signal amplifier 103 shown in FIG. 1, and is used to receive the radio frequency signal inside the communication device provided by the signal amplifier 103.
  • the output terminal Out is connected to the antenna 101 to filter the radio frequency signal provided by the internal function module of the terminal where the video communication module 10 is located, and then transmit it through the antenna 101.
  • the input terminal In may also be connected to the antenna 101 for receiving radio frequency signals from the antenna 101, and the output terminal Out is connected to the signal amplifier 103, so as to connect the wireless radio frequency signal received by the antenna 101 After the signal is filtered, it is provided to other functional modules inside the terminal.
  • the series resonator unit 110 is serially connected between the input terminal In and the output terminal Out, and the parallel resonator unit 120 is electrically connected between any node between the input terminal In and the output terminal Out and the ground terminal GND.
  • the first series resonator unit 110 includes at least one sub-series resonator unit connected in series.
  • the number of sub-series resonator units can be set according to the actual requirements of the filter circuit 100.
  • the first series resonator unit 110 includes four serially connected sub-resonator units, and is relative to the input terminal.
  • the sub-resonant unit at the last position is connected between the first node Nout and the output terminal Out.
  • each sub-series resonator unit SR1, sub-series resonator unit SR2, sub-series resonator unit SR3, and sub-series resonator unit SR4 are low-pass filters.
  • the sub-series resonator unit SR1, the sub-series resonator unit SR2, the sub-series resonator unit SR3, and the sub-series resonator unit SR4 start from the input terminal In, and are sequentially connected in series to the output terminal Out, and are relative to the input terminal.
  • the sub-series resonator unit SR4 at the last position is connected between the first node Nout and the output terminal Out.
  • the node between the sub-series resonator unit SR3 and the sub-series resonator unit SR4 is defined as the first node Nout.
  • the first node Nout is any node between the input terminal In and the output terminal Out, but there is no longer a node connection parallel resonator unit 120 between the first node Nout and the output terminal Out, that is, That is, since a parallel resonant unit 120 is connected to a node between the input terminal In and the output terminal Out, no matter how many parallel resonator units are included in the filter circuit 100, the first node Nout is compared to the input terminal In. The last node in position for connecting the parallel resonator unit 120, and at the same time, the first node Nout is also the nearest node in position for connecting the parallel resonator unit 120 compared to the output terminal Out. .
  • the first node Nout may also be set between the sub-series resonator unit SR1 and the sub-series resonator unit SR2, or between the sub-series resonator unit SR2 and the sub-series resonator unit SR3, but only the first node is required. No more parallel resonator units are provided between the node Nout and the output terminal Out between the node and the ground terminal GND.
  • Each sub-series resonator unit includes at least one series resonator.
  • the series resonator unit SR1 connected to the input terminal In includes two series resonators SR11 and S12
  • the series resonator unit SR4 connected to the output terminal Out includes two series resonators SR41 and SR42.
  • the other series sub-resonator units SR2 and SR3 located between the sub-series resonator unit SR1 and the sub-series resonator unit SR4 include a series resonator SR21 and SR31, that is, they are not directly connected to the input terminal In and the output terminal Out.
  • the connected sub-series resonator unit includes a series resonator.
  • the working parameters and structures of the series resonator SR11, the series resonator SR12, the series resonator SR21, the series resonator SR31, and the series resonators SR41-SR42 can be set to be the same according to the actual parameter requirements of the filter circuit 100, or Not exactly the same.
  • the number of series resonators included in each sub-series resonator unit can be adjusted according to actual requirements, and is not limited thereto.
  • the inductance L is connected between the input terminal In and the sub-series resonator unit SR1. At the same time, an inductance L is also provided between the sub-series resonator unit SR4 and the output terminal Out. The inductance L is used to connect with the series resonant unit 110 and the parallel resonator unit. 120 Perform parameter matching.
  • the inductor L may not be provided according to actual requirements.
  • the parallel resonator unit 120 is connected between the input terminal In and the output terminal Out, and is the first-stage parallel resonator unit closest to the output terminal Out, or in other words, the parallel resonator unit 120 is a distance from the input terminal In.
  • the parallel resonator unit 120 includes at least two parallel resonator branches 120a and 120b connected in parallel with each other. Wherein, each parallel resonator branch 120a, 120b includes at least one parallel resonator.
  • the parallel resonator branches 120a and 120b are respectively connected between the same first node Nout and the ground terminal GND, that is to say, the node connected to the input parallel resonator branch 120a and the node of the input parallel resonator branch 120b
  • the voltage is the same. That is, there is no sub-series resonator unit between the parallel resonator branches 120a and 120b.
  • the number M of parallel resonator branches and the number N of parallel resonators included in each parallel resonator branch may be the same or different.
  • M is a natural number greater than 2 or equal to 2
  • N is a natural number greater than 1 or equal to 1.
  • the parallel resonators in the parallel resonator unit 120 are arranged in a matrix of i*i, and i is a natural number greater than or equal to 2, less than or equal to M and N .
  • the parallel resonators in the parallel resonator unit 120 are arranged in a 2*2 matrix.
  • each parallel resonator branch 120a, 120b when each parallel resonator branch 120a, 120b includes a parallel resonator N greater than or equal to 2, the parallel resonators in each parallel branch 120a, 120b are connected in series.
  • the number of parallel resonators included in each parallel resonator branch 120a, 120b may be the same, for example, two or three; or, each parallel resonator branch 120a, 120b includes parallel resonators.
  • the number of resonators may be different.
  • the parallel resonator branch 120a includes two parallel resonators connected in series
  • the parallel resonator branch 120a includes three parallel resonators connected in series.
  • the parallel branch 120a when the parallel resonator branches 120a and 120b respectively include two parallel resonators connected in series, the parallel branch 120a includes a first parallel connection connected in series between the first node Nout and the ground terminal GND.
  • the first parallel resonator PR1 includes a first electrode PR1T of a first polarity and a second electrode PR1B of a second polarity
  • the second parallel resonator PR2 includes a third electrode PR2T of the first polarity and a second electrode PR1B.
  • the bipolar fourth electrode PR2B The first electrode PR1T is connected to the first node Nout
  • the second electrode PR1B is connected to the third electrode PR2T
  • the fourth electrode PR2B is connected to the ground terminal GND.
  • the first polarity is opposite to the second polarity, and the two electrodes of different polarities of the parallel resonator operate in opposite phases.
  • the fourth parallel resonator PR4 includes a seventh electrode PR4T and an eighth electrode PR4B
  • the fifth parallel resonator PR5 includes a ninth electrode PR5T and a tenth electrode PR5B.
  • the seventh electrode PR4T is connected to the first node Nout
  • the eighth electrode PR4B is connected to the ninth electrode PR5T
  • the tenth electrode PR5B is connected to the ground terminal GND.
  • the electrodes of the same polarity in the parallel resonator arranged at the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout.
  • the first electrode PR1T and the seventh electrode PR4T of the first polarity in the parallel resonator arranged in the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout.
  • the second electrode PR1B and the eighth electrode PR4B of the second polarity in the parallel resonator arranged at the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout.
  • the first electrode PR1T and the seventh electrode PR4T of the first polarity arranged in the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout, and at the same time, each parallel resonant branch
  • the fourth electrode PR2B and the tenth electrode PR5B of the second polarity arranged at the last position in the paths 120a and 120b are connected to the ground terminal GND.
  • the first electrode PR1T and the seventh electrode PR4T of the first polarity arranged in the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout, and at the same time, each parallel resonant branch
  • the fourth electrode PR2B and the tenth electrode PR5B of the second polarity arranged at the last position in the paths 120a and 120b are connected to the ground terminal GND.
  • the first electrode PR1T, the third electrode PR2T and the seventh electrode PR4T as the first polarity
  • the ninth electrode PR5T as the top electrode top
  • the second electrode PR1B and the fourth electrode PR2B as the second polarity
  • the eighth electrode PR4B and the bottom electrode of PR5B bottom are the first electrode PR1T, the third electrode PR2T and the seventh electrode PR4T as the first polarity
  • the ninth electrode PR5T as the top electrode top
  • the second electrode PR1B and the fourth electrode PR2B as the second polarity
  • the eighth electrode PR4B and the bottom electrode of PR5B bottom is the eighth electrode PR4B and the bottom electrode of PR5B bottom.
  • the series resonators in the multiple sub-series resonator units and the multiple parallel resonators in the parallel resonator unit 120 are all acoustic watch resonators.
  • the filtering working principle of the filtering circuit 100 is specifically described as follows:
  • FIG. 6 The working principle and characteristics of multiple sub-series resonator units are shown in Figure 6, where in Figure 6, the abscissa is the frequency, the ordinate is the scattering parameter (characterizing the transmission loss), and the symbol ⁇ as is the anti-resonance frequency of the series resonator.
  • the symbol ⁇ rs is the resonance frequency of the series resonator.
  • the series resonator (Series Resonator) in each series resonator unit exhibits a high impedance characteristic at the anti-resonant frequency ⁇ as and a low impedance characteristic at the resonant frequency ⁇ rs.
  • the series resonators all exhibit low-pass filtering characteristics.
  • the series connection of multiple series resonators cooperates to present low-pass filtering characteristics with higher suppression capability, that is, for signals with a frequency less than the frequency ⁇ rs
  • the self-series resonator unit 110 transmits through.
  • the series resonator is arranged in series between the input terminal In and the output terminal Out, and exhibits a high impedance characteristic at the anti-resonance frequency ⁇ as, and a low impedance characteristic at the resonance frequency ⁇ rs, so as to be able to Among the radio frequency signals input to the series resonator, the low frequency radio frequency signal can be transmitted through the series resonator, while the high frequency radio frequency signal is blocked or suppressed by the series resonator and cannot be transmitted through.
  • the working characteristics of the series resonators in each sub-series resonator unit are the same, that is, the anti-resonance frequency and the resonant frequency of each series resonator are the same. Therefore, the anti-resonance of each sub-series resonator unit The frequency coincides with the anti-resonance frequency of the series resonator it contains. The resonant frequency of each sub-series resonator unit coincides with the resonance frequency of the series resonator it contains. At the same time, the impedance characteristics of each sub-series resonator unit are also in series with the contained series resonator unit. The impedance characteristics of the resonators are the same.
  • Fig. 7 The working principle and characteristics of the parallel resonator (Parallel Resonator) in the parallel resonator unit 120 are shown in Fig. 7.
  • the abscissa is the frequency
  • the ordinate is the scattering parameter
  • the symbol ⁇ ap is the anti-resonance of the parallel resonator.
  • Frequency the symbol ⁇ rp is the resonant frequency of the parallel resonator; the parallel resonator in the parallel resonator unit has a high impedance characteristic at the resonant frequency ⁇ rp, and a low impedance characteristic at the anti-resonant frequency ⁇ ap.
  • the multiple parallel resonators in the parallel resonator unit 120 all exhibit high-pass characteristics, and the multiple parallel resonator branches formed by multiple parallel resonators cooperate to present high-pass filtering characteristics with higher suppression capability.
  • a signal with a frequency greater than the frequency ⁇ ap can be transmitted through the parallel resonator unit 120.
  • the parallel resonator is electrically connected in parallel between the node between the input terminal In and the output terminal Out and the ground terminal GND, and exhibits high impedance characteristics at the resonant frequency ⁇ rp, and exhibits at the anti-resonant frequency ⁇ ap. It is a low impedance characteristic, so that among the radio frequency signals input to the parallel resonator, the high frequency radio frequency signal can be output from the parallel resonator, while the low frequency radio frequency signal is blocked or suppressed by the parallel resonator and cannot be output.
  • the operating characteristics of the parallel resonators in the parallel resonator unit 120 are the same, that is, the anti-resonant frequency and resonant frequency of each parallel resonator are the same. Therefore, the anti-resonant frequency of the parallel resonator unit 120 is the same as that of the parallel resonator.
  • the anti-resonance frequencies of the parallel resonators included coincide with each other.
  • the resonance frequency of the parallel resonator unit 120 coincides with the resonance frequency of the parallel resonator included.
  • the impedance characteristics of the parallel resonator unit 120 are all coincident with the impedance of the parallel resonator included. The characteristics are the same.
  • the filtering principle of the filter circuit 100 for the radio frequency signal is shown in FIG. 8.
  • the frequency ⁇ rs closely coincides with the inverse frequency ⁇ ap point of the low impedance of the parallel resonator unit 120, forming the center frequency point of the passband of the filter circuit.
  • the center frequency of the band-pass filter circuit is the resonance frequency of the plurality of sub-series resonator units or the anti-resonance frequency of the parallel resonator unit 120.
  • the preset difference range is 0-30% ⁇ rs or 0-30% ⁇ ap.
  • the high impedance frequency points of the multiple sub-series resonator units and the parallel resonator unit 120 respectively correspond to the strong suppression points outside the passband of the formed filter circuit.
  • the PIM interference signal in passive intermodulation interference PIM is strongly related to the power borne by each resonator, that is, the greater the power borne by each resonator, the more the PIM interference signal generated by it. Also stronger.
  • the midstream of the radio frequency signal passes through a plurality of sub-series resonator units SR1 to SR4 for voltage division and low-pass filtering.
  • the radio frequency signal in conjunction with the radio frequency signal, it also passes through the parallel resonator unit 120 for shunting and high-pass filtering, and enters the parallel connection.
  • the radio frequency signal of the resonator unit 120 is divided by the parallel resonant branches 120a, 120b, and the two series parallel resonators in each parallel resonant branch are divided, thereby effectively reducing each series parallel resonator
  • the two-dimensional components of voltage and current are shared, so as to minimize the power shared by each parallel resonator in the parallel resonator unit 120, and thereby minimize the amplitude of the PIM interference signal. Since the power in each parallel resonator is reduced, the passive intermodulation interference of the filter circuit 100 is effectively suppressed.
  • each sub-series resonator unit and parallel resonator unit that passes through will generate a PIM interference signal, which will gradually accumulate.
  • the parallel resonator unit 120 can deal with the PIM generated by all the resonators in the parallel resonator unit between the input terminal In and the parallel resonator unit 120.
  • the interference signal is suppressed, so as to filter out most of the PIM interference signal generated by the entire filter circuit 100, thereby reducing the overall PIM interference signal of the filter circuit 100.
  • the parallel resonant branches 120a and 120b included in the parallel resonator unit 120 are connected in series with two parallel resonators, the PIM3 (3rd Passive Inter Modulation, third-order Intermodulation) is improved because the filter circuit PIM3 is the main component of PIM interference.
  • the PIM3 interference is suppressed, the interference generated by the filter circuit 100 as a whole is effectively suppressed, ensuring the quality of the filtered radio frequency signal.
  • only one parallel resonator unit 120 needs to be provided at the first node Nout, the volume of the filter circuit 100 is effectively reduced.
  • the working principle of filtering is basically the same, which will not be repeated in this embodiment.
  • both parallel resonators and series resonators are both surface acoustic wave resonators; when the filter circuit 100 is applied to a bulk acoustic wave filter (Bulk Acoustic Wave, BAW), both parallel resonators and series resonators can be bulk acoustic wave surface resonators.
  • the surface acoustic wave filter and the bulk acoustic wave filter respectively perform low-interference filtering processing for signals transmitted in the form of surface acoustic wave or bulk acoustic wave.
  • the surface acoustic wave is generated and transmitted along the surface of an elastic object. Bulk acoustic waves are sound waves that propagate in the depth direction inside the elastic solid.
  • FIG. 9 is a schematic diagram of the circuit structure of the filter circuit 200 shown in FIG. 1 in another embodiment of the application.
  • the structure of the filter circuit 200 is basically the same as that of the filter circuit 100 shown in FIG. 5, except that in addition to the parallel resonator unit 120, the filter circuit 200 also includes a second parallel resonator unit 140 and a second parallel resonator unit 140.
  • Three parallel resonator unit 150 the number of parallel resonator units included in the filter circuit 200 can be adjusted according to actual conditions.
  • a fourth parallel resonator unit can also be provided.
  • the parallel resonator unit 120 shown in FIG. 9 may be defined as the first parallel resonator unit 120.
  • the second parallel resonator unit 140 and the third parallel resonator unit 150 are connected between the node between two adjacent sub-series resonator units and the ground terminal GND, and the second parallel resonator unit 140 is connected to the ground terminal GND.
  • the third parallel resonator units 150 respectively include one parallel resonator.
  • the first The three-parallel resonator unit 150 is a parallel resonator unit one level closest to the input terminal In, or may be a first-stage parallel resonator unit, and the second parallel resonator unit 140 is a second-stage parallel resonator unit.
  • the resonator unit 120 is a parallel resonator unit at the last stage from the input terminal In, or the first parallel resonator unit 120 is a parallel resonator unit at the nearest stage from the output terminal Out.
  • the first parallel resonator unit 120 is the closest parallel resonator unit to the output terminal Out compared to the second parallel resonator unit 140 and the third parallel resonator unit 150. Therefore, no other parallel resonator unit is included between the first parallel resonator unit 120 and the output terminal Out, and the parallel resonator units except the first parallel resonator unit 120 are all disposed at the input terminal In and the first parallel resonator unit. Between a parallel resonator unit 120.
  • the second parallel resonator unit 140 is connected between the node N1 between the sub series resonator unit SR1 and the sub series resonator unit SR2 and the ground terminal GND; the third parallel resonator unit 140 is connected Between the node N2 between the sub-series resonator unit SR2 and the sub-series resonator unit SR3 and the ground GND.
  • the voltages between the first node Nout and the nodes N1 and N2 are different.
  • the first node Nout is the last node used to connect the parallel resonator unit compared to the input terminal In.
  • the first node The node Nout is also the closest node in position to the parallel resonator unit compared to the output terminal Out.
  • the parallel resonator PR04 included in the second parallel resonator unit 140 is connected between the node N1 and the ground terminal GND
  • the parallel resonator PR05 included in the third parallel resonator unit 150 is connected between the node N2 and the ground terminal GND.
  • the working parameters and structures of the parallel resonators included in each parallel resonator unit may be set to be the same according to actual parameter requirements of the filter circuit 100, or may not be completely the same.
  • the parallel resonator PR04, the parallel resonator PR05, and the first to fourth parallel resonators PR1 to PR4 can have the same working parameters and shapes and structures.
  • the parallel resonator PR04, parallel The working parameters, shapes and structures of the resonator PR05 and the first to fourth parallel resonators PR1 to PR4 may not be completely the same.
  • a second parallel resonator unit 140 is respectively provided between the node between two adjacent sub-series resonator units and the ground terminal GND, so that the intermodulation products (intermodulation interference signals) generated by the filter circuit 100 can be further reduced, and Effectively improve the efficiency of high-pass filtering for RF signals.
  • the parallel resonator branches 120a and 120b included in the parallel resonator unit 120 are connected in series with two parallel resonators, so that PIM3 (3rd Passive Inter Modulation) in passive intermodulation can be obtained.
  • PIM3 3rd Passive Inter Modulation
  • the overall interference generated by the filter circuit 100 is effectively suppressed, ensuring the quality of the filtered radio frequency signal.
  • FIG. 10 is a schematic diagram of the circuit structure of the filter circuit 300 shown in FIG. 1 in another embodiment of the application.
  • the structure of the filter circuit 300 is basically the same as that of the filter circuit 200 shown in FIG. 9 except that, in the filter circuit 300, the number of parallel resonators in series included in the parallel resonator branches 120a and 120b is 3. , That is, the parallel resonator branches 120a and 120b respectively include three parallel resonators connected in series.
  • the parallel branch 120a includes a first parallel resonator PR1, a second parallel resonator PR2, and a third parallel resonator connected in series between the first node Nout and the ground terminal GND.
  • the first parallel resonator PR1 includes a first electrode PR1T of a first polarity and a second electrode PR1B of a second polarity
  • the second parallel resonator PR2 includes a third electrode PR2T of the first polarity and a second electrode PR1B.
  • the third parallel resonator PR3 includes a fifth electrode PR3T with a first polarity and a sixth electrode PR3B with a second polarity.
  • the first electrode PR1T is connected to the first node Nout
  • the second electrode PR1B is connected to the third electrode PR2T
  • the fourth electrode PR2B is connected to the fifth electrode PR3T
  • the sixth electrode PR3B is connected to the ground terminal GND.
  • the fourth parallel resonator PR4 includes a seventh electrode PR4T and an eighth electrode PR4B
  • the fifth parallel resonator PR5 includes a ninth electrode PR5T and a tenth electrode PR5B
  • the sixth parallel resonator PR6 includes an eleventh electrode PR6T and a twelfth electrode PR5B. Electrode PR6B.
  • the seventh electrode PR4T is connected to the output terminal Out
  • the eighth electrode PR4B is connected to the ninth electrode PR5T
  • the tenth electrode PR5B is connected to the eleventh electrode PR6T
  • the twelfth electrode PR6B is connected to the ground terminal GND.
  • the electrodes of the same polarity in the parallel resonator arranged in the first position in each parallel resonant branch 120a, 120b are connected to the output terminal Out.
  • the first electrode PR1T and the seventh electrode PR4T of the first polarity arranged in the first position in each parallel resonant branch 120a, 120b are connected to the first node Nout, and at the same time, each parallel resonant branch 120a,
  • the sixth electrode PR3B and the twelfth electrode PR6B of the second polarity arranged at the last position in 120b are connected to the ground terminal GND.
  • the first electrode PR1T and the seventh electrode PR4T of the first polarity arranged in the first position in each parallel resonant branch 120a and 120b are connected to the ground terminal GND, and at the same time, each parallel resonant branch
  • the sixth electrode PR3B and the twelfth electrode PR6B of the second polarity arranged at the last position among 120a and 120b are connected to the first node Nout.
  • each parallel resonator in the parallel resonator unit 120 is routed to include three parallel resonators in series. Then, the RF signal can be further divided into voltage, thereby further reducing the load on each parallel resonator. Therefore, the intermodulation products (PIM interference signal) generated by the filter circuit 100 can be further reduced.
  • the parallel resonator branches 120a and 120b included in the parallel resonator unit 120 are connected in series with three parallel resonators, so that PIM3 (3rd Passive Inter Modulation) in passive intermodulation can be obtained. Effective improvement, because the filter circuit PIM3 is the main component of PIM interference. When the PIM3 interference is suppressed, the overall interference generated by the filter circuit 100 is effectively suppressed, ensuring the quality of the filtered radio frequency signal.
  • FIG. 11 is a schematic diagram of the circuit structure of the filter circuit 400 shown in FIG. 1 in another embodiment of the application.
  • the structure of the filter circuit 400 is basically the same as that of the filter circuit 200 shown in FIG. 9, except that in the filter circuit 300, the number M of parallel resonator branches included in the first parallel resonator unit 120 is 3.
  • the number N of parallel resonators included in each parallel resonator branch is two. That is, the first parallel resonator unit 120 includes three parallel resonator branches, and each parallel resonator branch includes two parallel resonators connected in series.
  • the first parallel resonator unit 120 includes at least three parallel resonator branches 120a, 120b, and 120c connected in parallel with each other.
  • the circuit structure and connection manner of the parallel resonator branches 120a and 120b shown in FIG. 11 are the same as the circuit structure and connection manner of the parallel resonator branches 120a and 120b shown in FIG.
  • the parallel resonator branch 120c includes a seventh parallel resonator PR7 and an eighth parallel resonator PR8 connected in series between the output terminal Out and the ground terminal GND.
  • the seventh parallel resonator PR7 includes the thirteenth electrode PR7T of the first polarity and the fourteenth electrode PR7B of the second polarity
  • the eighth parallel resonator PR8 includes the fifteenth electrode PR8T of the first polarity and the fourth electrode PR8T.
  • the sixteenth electrode PR2B with two polarities.
  • the thirteenth electrode PR7T is connected to the node Nout closest to the output terminal Out
  • the fourteenth electrode PR7B is connected to the fifteenth electrode PR8T
  • the sixteenth electrode PR2B is connected to the ground terminal GND.
  • the parallel resonant branches 120a, 120b, and 120c included in the parallel resonator unit 120 respectively connect two parallel resonators in series. Therefore, since the parallel resonator unit 120 includes three parallel resonator branches, then , It can further shunt the radio frequency signal, thereby further reducing the current and power on each parallel resonator, enabling the PIM3 (3rd Passive Inter Modulation) in passive intermodulation to be further improved and filtering The interference generated by the circuit 100 as a whole is effectively suppressed, and the quality of the filtered radio frequency signal is ensured.
  • PIM3 3rd Passive Inter Modulation

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Abstract

一种无源互调性能较佳的滤波电路（100）、包括前述滤波电路（100）的双工器（100a）与通信装置（1），滤波电路（100）包括接收射频信号的输入端（In）、串联谐振器单元（110）、并联谐振单元（120）与输出端（Out），串联谐振器单元（110）连接于输入端（In）与输出端（Out）之间，并联谐振器单元（120）与串联谐振器单元（110）配合针对射频信号进行滤波并从输出端（Out）输出。并联谐振器单元（120）包括至少2个相互并联的并联谐振器支路（120a，120b），并联谐振器支路（120a，120b）均连接于输入端（In）与输出端（Out）之间第一节点（Nout）与接地端（GND）之间，每个并联谐振器支路（120a，120b）包括至少一个并联谐振器，并联谐振器单元为距离输出端（Out）最近一级的并联谐振器单元。并联谐振器包括第一电极与第二电极，每一个并联谐振器支路中连接于第一节点（Nout）的电极均相同。

Description

滤波电路、双工器、通信装置
本申请要求于2019年11月29日提交中国专利局、申请号为201911211785.6、申请名称为“滤波电路、双工器、通信装置”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请实施例涉及无线射频通信技术领域，尤其涉及一种滤波电路、双工器和通信装置
背景技术
随着通信装置在人们生活中广泛应用，无线信号的品质作为通信装置其中一个重要参数来衡量通信装置整体品质。通信装置中无线信号的发射与接收均需要使用到滤波器执行滤波处理，由此，滤波器对无线信号的品质影响较大。
目前，随着通信装置中无线信号通道数量的增多，每个无线信号通道中滤波器之间的无源互调干扰(Passive Inter Modulation，PIM)较大，导致各个通道内传输的无线射频信号具有较大的无源互调干扰噪声，进而影响通信装置的整体品质。
发明内容
为解决前述问题，本申请一实施例提供一种滤波电路、双工器和通信装置，通过调整距离滤波电路输出端最近一级并联谐振器单元中的电路结构，从而有效提高了滤波电路干扰抑制能力，使得滤波电路的无源互调较佳。
第一方面，本申请实施例提供一种滤波电路，其包括输入端、串联谐振器单元、并联谐振单元与输出端。其中，所述输入端用于接收射频信号，所述一个串联谐振器单元连接于所述输入端与所述输出端之间，所述串联谐振器单元与所述并联谐振器单元配合针对所述射频信号执行滤波后从所述输出端输出。所述并联谐振器单元包括M个相互并联的并联谐振器支路，所述M个并联谐振器支路均连接于所述输入端与所述输出端之间第一节点与接地端之间，且所述M个并联谐振器之路中的每一个并联谐振器支路包括至少一个并联谐振器，所述并联谐振器单元为距离所述输出端最近一级的并联谐振器单元，M为大于或者等于2的自然数。
每一个并联谐振器包括第一极性的第一电极与第二极性的第二电极，其中，所述每一个并联谐振器支路中连接于所述第一节点的电极均为第一极性的第一电极；或者，每一个并联谐振器支路中连接于所述第一节点的电极均为第二极性的第二电极。
由于距离所述输出端最近一级的并联谐振器单元中包括的两个并联谐振支路，从而能够使得无源互调中的PIM3得到提升进而使得滤波电路整体产生的干扰得到有效抑制，保证了针对无线射频信号滤波后的品质，并且两个并联谐振支路中并联谐振器连接于第一节点的电极的极性相同，使得并联谐振支路设置更为简便。另外，由于通过在第一节点设置一个并联谐振器单即可使得干扰得到有效抑制，从而有效降低了滤波电路整体的体积。
本申请一实施例中，当每一个所述并联谐振器支路包括两个或两个以上谐振器时，所述两个或者两个以上并联谐振器相互串联。由于并联谐振器是连续串联设置，从而使得并联谐振器连接方式更为简便。
本申请一实施例中，当每一个所述并联谐振器支路包括两个或者三个谐振器时，并联谐振器单元能够中并联谐振器的数量与干扰抑制能力能够达到最佳的平衡点，也即是此时滤波电路的干扰抑制较佳且由于并联谐振器数量较少而保证滤波电路整体体积较小。
本申请一实施例中，每一个所述并联谐振器支路中串联的并联谐振器数量不相同，通过调整每个所述并联谐振器支路中并联谐振器的数量来调整滤波电路的干扰抑制能力，使得滤波电路的干扰抑制能力能够灵活地进行调整。
本申请一实施例中，所述串联谐振器单元在反谐振频率处呈现高阻抗特性，所述并联谐振器单元在谐振频率处呈现高阻抗特性，所述串联谐振器单元与所述并联谐振器单元构成带通滤波器，所述带通滤波器的中心频率为所述串联谐振器单元的谐振频率或者为所述并联谐振器单元的反谐振频率。通过串联谐振器单元与并联谐振器单元相互配合，使得滤波电路针对接收的射频信号进行滤波的同时还能够有效抑制干扰。
本申请一实施例中，所述滤波电路可以为表面声波滤波器或者可以为体声波滤波器，从而通过分别针对声表面波形式或者体声波形式传输的信号进行较低干扰的滤波处理。
第二方面，本申请实施例提供一种无源互调较佳的双工器，其包括两个前述的滤波器，所述两个滤波器分别在射频信号接收方向与射频信号发送方向针对射频信号执行滤波，从而使得发送方向与接收方向均能够针对射频信号进行滤波处理时，使得干扰进行较佳的抑制以及使得无源互调较佳。
第三方面，本申请实施例提供一种通信装置，至少包括有前述滤波电路，所述滤波电路能够对发射频段或者接收频段中的射频信号进行滤波处理时的干扰进行较佳的抑制以及使得无源互调较佳，从而使得通信装置中传输的信号品质较佳。
本申请一实施例中，通信装置还包括天线，所述天线与所述滤波电路连接，所述天线用于接收待滤波电路执行滤波处理的射频信号，以及发射经滤波电路滤波完成后的射频信号。
附图说明
图1为射频通信模组的功能模块图；
图2为本申请一实施例中双工器的功能模块图；
图3为本申请一实施例中图1所示的射频通信模组应用的通信装置的结构示意图；
图4为本申请一实施例中图1所示的射频通信模组应用的通信装置的结构示意图；
图5为本申请一实施例中如图1所示滤波器的电路结构示意图；
图6为子串联谐振器单元工作特性中射频信号波形示意图；
图7为第一并联谐振器单元工作特性中射频信号波形示意图；
图8为图4所示滤波器工作特性中射频信号波形示意图；
图9为本申请又一实施例中如图1所示滤波器的电路结构示意图；
图10为本申请又一实施例中如图1所示滤波器的电路结构示意图；
图11为本申请又一实施例中如图1所示滤波器的电路结构示意图。
具体实施方式
请参阅图1，其为射频通信模组的功能模块图。如图1所示，射频通信模组10包括滤波电路100、天线101以及信号放大器103。滤波电路100连接于天线101与信号放大器103。其中，本实施例中所述的连接为通过导电线路进行电性连接并且能够执行电信号的传输。
天线101用于按照不同的频率向其他通信装置发送无线信号，或者自其他通信装置接收信号无线信号。本实施例中，滤波电路100用于在发射频段中，从信号放大器103向天线101馈送信号，或者本申请其他实施例中，滤波电路100也可以应用在在接收频段中，从天线20向信号放大器103馈送信号。同时，滤波电路100能够抑制处于接收频段或者发送频段的各个频率，也即是针对接收频段上的射频信号进行滤波处理。
本实施例中，滤波电路100应用于滤波器或者说滤波电路100即为滤波器，以针对接收频段中或者发射频段中的射频信号执行滤波处理。
本实施例中，图1仅示出了一个信号放大器103，但是信号放大器103可以包括接收频段进行处理的低噪声放大器以及发射频段功率放大器，并且放大器级的数目以及级间滤波器的数目可以依据实际情况进行设定。
需要说明的是，本实施例中，滤波电路100为单通道针对射频信号进行滤波，也即是滤波电路100单独针对发射频段中的射频信号进行滤波，或者单独针对接收频段中的视频信号进行滤波。
如图2所示，在本申请一实施例中，由两个滤波电路100构成双通道滤波的双工器100a，当然，在本申请其他实施例中，还可以由三个及其以上滤波电路100构成多通道的多工器的。
具体地，如图2所示，双工器100a中两个滤波电路100分别沿不同方向接收射频信号然后执行滤波处理，例如其中一个滤波电路100针对需要传输至天线101向外部发射的发射频段(TX)中的射频信号进行滤波，然后另一个滤波电路100针对自天线101提供的接收频段(RX)中的射频信号进行滤波。另外，双工器100还包括用于将发射频段和接收频段分开的功能电路(图未示)，但是本实施例中，两个滤波器100电路结构基本相同。
通过将滤波电路100或者包含有滤波电路100的双工器100a纳入到移动通信设备或网络设备的设计之中，滤波电路100能够对发射频段的射频信号或者接收频段的射频信号中的干扰得以降低。
本实施例中，滤波电路100可以应用在声表面波滤波器(Surface Acoustic Wave，SAW)，在本申请其他实施例中，滤波电路100也可以为应用在体声波滤波器(Bulk Acoustic Wave,BAW)中。
请参阅图3，其为本申请一实施例中图1所示的射频通信模组10应用的通信装置1的 结构示意图。
本实施例中，通信装置1为网络设备，所述网络设备包括基站(base station，BS)，所述基站中包括图1所示的射频通信模组10。基站可以是一种部署在无线接入网中能够和终端进行无线通信的设备。其中，基站可能有多种形式，比如宏基站、微基站、中继站和接入点等。示例性地，本申请实施例涉及到的基站可以是5G中的基站或LTE中的基站，其中，5G中的基站还可以称为发送接收点(transmission reception point，TRP)或gNB。本申请实施例中，用于实现网络设备的功能的装置可以是网络设备；也可以是能够支持网络设备实现该功能的装置，例如芯片系统，该装置可以被安装在网络设备中。
请参阅图4，其为本申请一实施例中图1所示的射频通信模组10应用的通信装置1的结构示意图。
本实施例中，通信装置1可以为移动通信设备，例如手机、平板电脑等，其中，移动通信设备可以包括图1所示的射频通信模组10。
请参阅图5，其为本申请一实施例中如图1所示滤波电路100的电路结构示意图。
如图5所示，滤波电路100包括输入端In、电感L、串联谐振单元110、并联谐振单元120与输出端Out。
本实施例中，输入端In连接于图1所示的信号放大器103，用于接收自信号放大器103提供的通信装置内部的无线射频信号。输出端Out连接于天线101，以将视频通信模组10所在终端的内部功能模组提供的无线射频信号进行滤波处理后通过天线101发射。
当然，在本申请其他实施例中，输入端In还可以连接于天线101，用于接收自天线101的无线射频信号，输出端Out连接于信号放大器103，从而将天线101接收的无线形式的射频信号滤波处理后提供至终端内部的其他功能模组。
串联谐振器单元110串行连接于输入端In与输出端Out之间，并联谐振器单元120电性输入端In与输出端Out之间任意节点与接地端GND之间。
本实施例中，第一串联谐振器单元110包括至少一个依次串联的子串联谐振器单元。其中，子串联谐振器单元的数量可以依据滤波电路100实际需求参数进行设定，例如如图4所示第一串联谐振器单元110包括4个依次串联的子谐振器单元，且相对于输入端In而言，处于最末位置的子谐振单元连接于第一节点Nout与输出端Out之间。本实施例中，为了便于说明，四个子串联谐振器单元分别定义为子串联谐振器单元SR1、子串联谐振器单元SR2、子串联谐振器单元SR3以及子串联谐振器单元SR4。其中，每个子串联谐振器单元SR1、子串联谐振器单元SR2、子串联谐振器单元SR3以及子串联谐振器单元SR4均为低通滤波。
更为具体地，子串联谐振器单元SR1、子串联谐振器单元SR2、子串联谐振器单元SR3以及子串联谐振器单元SR4自输入端In开始，依次串联连接于输出端Out，且相对于输入端In而言处于最末位置的子串联谐振器单元SR4连接于第一节点Nout与输出端Out之间。也即是说，子串联谐振器单元SR3以及子串联谐振器单元SR4之间的节点定义为第一节点Nout。
本申请实施例中，第一节点Nout为输入端In与输出端Out之间任意一个节点，但是该第一节点Nout与输出端Out之间不再设置有节点连接并联谐振器单元120，也即是说，由于一个并联谐振单元120连接于输入端In与输出端Out之间的一个节点，无论滤波电路100包括多少个并联谐振器单元，该第一节点Nout为相较于输入端In而言在位置上最末一个用来连接并联谐振器单元120的节点，同时，该第一节点Nout也是相较于输出端Out而言在位置上最邻近的一个用来连接并联谐振器单元120的节点。
举例而言，第一节点Nout也可以设置在子串联谐振器单元SR1与子串联谐振器单元SR2之间，或者子串联谐振器单元SR2与子串联谐振器单元SR3之间，但仅需第一节点Nout与输出端Out之间不再有节点与接地端GND之间设置其他的并联谐振器单元即可。
每个子串联谐振器单元包括至少一个串联谐振器。本实施例中，连接于输入端In的串联谐振器单元SR1包括两个串联的串联谐振器SR11、S12，连接于输出端Out的串联谐振器单元SR4包括两个串联的串联谐振器SR41、SR42。而位于子串联谐振器单元SR1与子串联谐振器单元SR4之间的其他子串联谐振器单元SR2、SR3，包括一个串联谐振器SR21、SR31，也即是未与输入端In与输出端Out直接连接的子串联谐振器单元包括一个串联谐振器。
本实施例中，串联谐振器SR11、串联谐振器SR12、串联谐振器SR21、串联谐振器SR31以及串联谐振器SR41-SR42的工作参数和结构可以依据滤波电路100实际参数需求设置为一样，也可以不完全相同。
在本申请其他实施例中，每一个子串联谐振器单元中包括的串联谐振器数量可以依据实际需求进行调整，并不以此为限。
电感L连接于输入端In与子串联谐振器单元SR1之间，同时，子串联谐振器单元SR4与输出端Out之间也设置有电感L，电感L用于与串联谐振单元110、并联谐振单元120执行参数匹配。当然，在本申请其他实施例中，也可以依据实际需求并不需要设置电感L。
本实施例中，并联谐振器单元120连接于输入端In与输出端Out之间，并且为最邻近输出端Out的一级并联谐振器单元，或者说，并联谐振器单元120为距离输入端In最末一级的并联谐振器单元，由此，并联谐振器单元120与输出端Out之间则不再包括其他任何的并联谐振器单元。
并联谐振器单元120包括至少两个相互并联的并联谐振器支路120a、120b。其中，每一个并联谐振器支路120a、120b包括至少一个并联谐振器。
并联谐振器支路120a、120b均分别连接于同一个第一节点Nout与接地端GND之间，也即是说，输入并联谐振器支路120a连接的节点与输入并联谐振器支路120b节点的电压相同。也即是，并联谐振器支路120a、120b之间并未设置子串联谐振器单元。
其中，并联谐振器支路的数量M与每一个并联谐振器支路中包括的并联谐振器数量N可以相同，也可以不同。其中，M为大于2或者等于2的自然数，N为大于1或者等于1的自然数。
更为具体地，当M与N相同时，例如均为i，并联谐振器单元120中的并联谐振器呈i*i的矩阵排列，i为大于或者等于2、小于或者等于M、N的自然数。
举例而言，当并联谐振器支路的数量M与每个并联谐振器支路中并联谐振器数量N均 为2时，并联谐振器单元120中的并联谐振器呈2*2的矩阵排列。
本实施例中，每一个并联谐振器支路120a、120b分别包括并联谐振器N大于或者等于2时，每一个并联支路120a、120b中的并联谐振器为依次串联。每一个并联谐振器支路120a、120b分别包括的并联谐振器的数量可以相同，例如均为2个，或者均为3个；或者，每一个并联谐振器支路120a、120b分别包括的并联谐振器的数量可以不相同，例如，并联谐振器支路120a包括为2个串联的并联谐振器，而并联谐振器支路120a包括为3个串联的并联谐振器。
本实施例中，当并联谐振器支路120a、120b分别包括2个串联的并联谐振器时，对于并联支路120a而言，包括串联于第一节点Nout与接地端GND之间的第一并联谐振器PR1与第二并联谐振器PR2；对于并联支路120b而言，包括串联于第一节点Nout与接地端GND之间的第四并联谐振器PR4与第五并联谐振器PR6。
更为具体地，第一并联谐振器PR1包括第一极性的第一电极PR1T与第二极性的第二电极PR1B，第二并联谐振器PR2包括第一极性的第三电极PR2T与第二极性的第四电极PR2B。其中，第一电极PR1T连接于第一节点Nout，第二电极PR1B连接于第三电极PR2T，第四电极PR2B连接于接地端GND。第一极性与第二极性的极性相反，且并联谐振器的两个不同极性的电极运行在相反的相位上。
第四并联谐振器PR4包括第七电极PR4T与第八电极PR4B，第五并联谐振器PR5包括第九电极PR5T与第十电极PR5B。其中，第七电极PR4T连接于第一节点Nout，第八电极PR4B连接于第九电极PR5T，第十电极PR5B连接于接地端GND。
每个并联谐振支路120a、120b中排列在第一位置并联谐振器中相同极性的电极连接第一节点Nout。例如，如图4所示每个并联谐振支路120a、120b中排列在第一位置并联谐振器中第一极性的第一电极PR1T与第七电极PR4T连接第一节点Nout。或者，在本申请其他实施例中，每个并联谐振支路120a、120b中排列在第一位置并联谐振器中第二极性的第二电极PR1B与第八电极PR4B连接第一节点Nout。
具体地，本实施例中，每个并联谐振支路120a、120b中排列在第一位置第一极性的第一电极PR1T、第七电极PR4T连接第一节点Nout，同时，每个并联谐振支路120a、120b中排列在第末位置第二极性的第四电极PR2B、第十电极PR5B连接接地端GND。
在本申请其他实施例中，每个并联谐振支路120a、120b中排列在第一位置第一极性的第一电极PR1T、第七电极PR4T连接第一节点Nout，同时，每个并联谐振支路120a、120b中排列在第末位置第二极性的第四电极PR2B、第十电极PR5B连接接地端GND。
本实施例中，作为第一极性的第一电极PR1T、第三电极PR2T与第七电极PR4T、第九电极PR5T为顶部电极top，作为第二极性的第二电极PR1B、第四电极PR2B、第八电极PR4B以及PR5B底部电极bottom。
另外，本实施例中，多个子串联谐振器单元中的串联谐振器与并联谐振器单元120中的多个并联谐振器均为声表谐振器。
结合图5，具体说明滤波电路100滤波工作原理为：
多个子串联谐振器单元的工作原理与特性如图6所示，其中，图6中，横坐标为频率，纵坐标为散射参数(表征传输损耗)，符号ωas为串联谐振器的反谐振频率，符号ωrs为 串联谐振器的谐振频率。如图6所示，每个串联谐振器单元中的串联谐振器(Series Resonator)在反谐振频率ωas处表现为高阻抗特性，在谐振频率ωrs处表现为低阻抗特性。本实施例中，串联谐振器均呈现低通滤波特性，通过多个串联谐振器的串行连接配合呈现更高抑制能力的低通滤波特性，也即是说，对于频率小于频率ωrs的信号能够自串联谐振器单元110传输通过。
需要说明的是，串联谐振器为串行设置于输入端In与输出端Out之间，并且反谐振频率ωas处表现为高阻抗特性，在谐振频率ωrs处表现为低阻抗特性，以能够针对使得输入串联谐振器的射频信号中，低频段的射频信号能够自串联谐振器传输通过，而高频段的射频信号被串联谐振器阻挡或者抑制而无法传输通过。
本实施例中，每个子串联谐振器单元中的串联谐振器的工作特性相同，也即是每个串联谐振器的反谐振频率以及谐振频率相同，由此，每个子串联谐振器单元的反谐振频率与其包含的串联谐振器的反谐振频率重合，每个子串联谐振器单元的谐振频率与其包含的串联谐振器的谐振频率重合，同时，每个子串联谐振器单元的阻抗特性也均与其包含的串联谐振器的阻抗特性相同。
并联谐振器单元120中并联谐振器(Parallel Resonator)的工作原理与特性如图7所示，其中，图7中，横坐标为频率，纵坐标为散射参数，符号ωap为并联谐振器的反谐振频率，符号ωrp为并联谐振器的谐振频率；并联谐振器单元中的并联谐振器在谐振频率ωrp处表现为高阻抗特性，在反谐振频率ωap处表现为低阻抗特性。本实施例中，并联谐振器单元120中多个并联谐振器均呈现高通特性，通过多个并联谐振器构成的多个并行连接的并联谐振器支路配合呈现更高抑制能力的高通滤波特性，也即是说，对于频率大于频率ωap的信号能够自并联谐振器单元120传输通过。
需要说明的是，并联谐振器为并行电连接于输入端In与输出端Out之间的节点与接地端GND之间，并且在谐振频率ωrp处表现为高阻抗特性，在反谐振频率ωap处表现为低阻抗特性，以能够针对使得输入并联谐振器的射频信号中，高频段的射频信号能够自并联谐振器输出，而低频段的射频信号被并联谐振器阻挡或者抑制而无法输出。
本实施例中，并联谐振器单元120中的并联谐振器的工作特性相同，也即是每个并联谐振器的反谐振频率以及谐振频率相同，由此，并联谐振器单元120的反谐振频率与其包含的并联谐振器的反谐振频率重合，并联谐振器单元120的谐振频率与其包含的并联谐振器的谐振频率重合，同时，并联谐振器单元120的阻抗特性也均与其包含的并联谐振器的阻抗特性相同。
通过分别控制多个子串联谐振器单元与并联谐振器单元120的谐振频率和反谐振频率，滤波电路100针对射频信号的滤波原理如图8所示，当多个串联谐振器单元的处于低阻抗的频率ωrs与并联谐振器单元120的低阻抗的反频率ωap点接近于重合，构成滤波电路通带的中心频点，当多个子串联谐振器单元的谐振频率与所述并联谐振器单元120的反谐振频率之间的差值位于预设差值范围内时，所述带通滤波电路的中心频率为所述多个子串联谐振器单元的谐振频率或者所述并联谐振器单元120的反谐振频率。本实施例中，所述预设差值范围为0～30％ωrs或者0～30％ωap。
本实施例中，多个子串联谐振器单元以及并联谐振器单元120的高阻抗频率点分别对 应构成的滤波电路通带外的强抑制点。
进一步，经过深入研究发现，无源互调干扰PIM中的PIM干扰信号和每个谐振器上承受的功率强相关，即单独每个谐振器上承担的功率越大，通常其产生的PIM干扰信号也越强。
本实施例中，射频信号中流经过多个子串联谐振器单元SR1～SR4进行分压与低通滤波处理，同时，配合射频信号还经过并联谐振器单元120进行分流以及高通滤波处理，并且，进入并联谐振器单元120的射频信号由并联谐振支路120a、120b的分流，以及每个并联谐振支路中的两个串联的并联谐振器进行分压，由此有效减小每个串联的并联谐振器分担的电压与电流两个维度的分量，从而最大程度的减小并联谐振器单元120中每一个并联谐振器分担的功率，进而最大程度减小PIM干扰信号的幅度。由于每个并联谐振器中功率得到降低，从而有效抑制了滤波电路100无源互调干扰。
同时，由于因为滤波电路100中，射频信号自输入端In进入滤波电路100开始，经过的每一个子串联谐振器单元以及并联谐振器单元均会产生PIM干扰信号，且会逐步累加。当并联谐振器单元120针对射频信号执行最后一级的滤波处理，那么并联谐振器单元120就能够针对输入端In与并联谐振器单元120之间的并联谐振器单元中全部谐振器所产生的PIM干扰信号进行抑制，从而滤除掉整个滤波电路100产生的大部分PIM干扰信号，进而减小滤波电路100的整体PIM干扰信号。
同时，在第一并联谐振器120之后就不会再有其他的并联谐振器单元继续产生无源互调干扰。由此，仅需在距离输出端Out最近的节点设置并联谐振器单元即可有效减小滤波电路100的互调产物(PIM干扰信号)。
由此，本实施例中，由于并联谐振器单元120中包括的并联谐振支路120a、120b分别串联的两个并联谐振器，能够使得无源互调中的PIM3(3rd Passive Inter Modulation，三阶互调)得到提升，因为滤波电路PIM3是PIM干扰的主要构成，当PIM3干扰被抑制后，滤波电路100整体产生的干扰得到有效抑制，保证了针对无线射频信号滤波后的品质。进一步，由于仅需在第一节点Nout设置一个并联谐振器单元120，从而有效降低了滤波电路100的体积。
本实施例中，包含有两个滤波电路100的双工器100a时执行滤波的工作原理基本相同，本实施例不再赘述。
本实施例中，当滤波电路100应用在声波表面波滤波器(Surface Acoustic Wave,SAW)时，并联谐振器与串联谐振器均为可以声波表面谐振器；当滤波电路100应用在体声波滤波器(Bulk Acoustic Wave,BAW)时，并联谐振器与串联谐振器均可以为体声波表面谐振器。其中，声波表面波滤波器与体声波滤波器分别为针对声表面波形式或者体声波形式传输的信号进行较低干扰的滤波处理，其中，声表面波为沿弹性物体表面产生并沿着表面传输的声波，而体声波为声波在弹性固体内部沿纵深方向传播。
请参阅图9，其为本申请又一实施例中如图1所示滤波电路200的电路结构示意图。本实施例中，滤波电路200与图5所示滤波电路100的结构基本相同，区别仅在于，滤波电路200中，除了并联谐振器单元120之外，还包括第二并联谐振器单元140、第三并联谐振器单元150。当然，滤波电路200包括的并联谐振器单元的数量可以依据实际情况进 行调整，例如还可以设置第四并联谐振器单元。其中，为了便于说明，图9所示的并联谐振器单元120可以定义为第一并联谐振器单元120。
本实施例中，第二并联谐振器单元140与第三并联谐振器单元150连接于相邻两个子串联谐振器单元之间的节点与接地端GND之间，且第二并联谐振器单元140与第三并联谐振器单元150分别包括一个并联谐振器。
本实施例中，按照与输入端In以及输出端Out之间的距离关系以及第一并联谐振器单元120、第二并联谐振器单元140以及第三并联谐振器单元150的位置顺序而言，第三并联谐振器单元150为距离输入端In最近一级的并联谐振器单元，也可以为第一级并联谐振器单元，第二并联谐振器单元140为第二级并联谐振器单元，第一并联谐振器单元120为距离输入端In最末一级的并联谐振器单元，或者说第一并联谐振器单元120为距离输出端Out最近一级的并联谐振器单元。
其中，第一并联谐振器单元120相较于第二并联谐振器单元140、第三并联谐振器单元150是距离输出端Out的最近一级的并联谐振器单元。由此，第一并联谐振器单元120与输出端Out之间并未包含有其他并联谐振器单元，而除第一并联谐振器单元120之外的并联谐振器单元均设置于输入端In与第一并联谐振器单元120之间。
例如，如图9所示，第二并联谐振器单元140连接于子串联谐振器单元SR1与子串联谐振器单元SR2之间的节点N1与接地端GND之间；第三并联谐振器单元140连接于子串联谐振器单元SR2与子串联谐振器单元SR3之间的节点N2与接地端GND之间。本实施例中，第一节点Nout与节点N1、N2之间的电压不同。此时，该第一节点Nout、节点N1、节点N3中，第一节点Nout为相较于输入端In而言在位置上最末一个用来连接并联谐振器单元的节点，同时，该第一节点Nout也是相较于输出端Out而言在位置上最邻近的一个用来连接并联谐振器单元的节点。
具体地，第二并联谐振器单元140包括的并联谐振器PR04连接于节点N1与接地端GND之间，第三并联谐振器单元150包括的并联谐振器PR05连接于节点N2与接地端GND之间。各个并联谐振器单元所包含的并联谐振器的工作参数和结构可以依据滤波电路100实际参数需求设置为一样，也可以不完全相同。
例如，并联谐振器PR04、并联谐振器PR05以及第一～第四并联谐振器PR1～PR4的工作参数和形状结构可以相同，当然，在滤波电路100实际参数需求调整时，并联谐振器PR04、并联谐振器PR05以及第一～第四并联谐振器PR1～PR4的工作参数和形状结构可以不完全相同。
本实施例中，除在第一节点Nout与接地端GND之间设置并联谐振器单元120、同时配合连接在第一节点Nout与输出端Out之间的子串联谐振器单元SR4，还进一步针对任意相邻两个子串联谐振器单元之间的节点与接地端GND之间分别设置有第二并联谐振器单元140，从而能够进一步降低滤波电路100所产生的互调产物(互调干扰信号)，并且有效提高针对射频信号的高通滤波功效。
本实施例中，并联谐振器单元120中包括的并联谐振支路120a、120b分别串联的两个并联谐振器，能够使得无源互调中的PIM3(3rd Passive Inter Modulation，三阶互调)得到有效提升，因为滤波电路PIM3是PIM干扰的主要构成，当PIM3干扰被抑制后，滤波电 路100整体产生的干扰得到有效抑制，保证了针对无线射频信号滤波后的品质。
请参阅图10，其为本申请又一实施例中如图1所示滤波电路300的电路结构示意图。本实施例中，滤波电路300与图9所示滤波电路200的结构基本相同，区别仅在于，滤波电路300中，并联谐振器支路120a、120b包括的串联的并联谐振器的数量N为3，也即是并联谐振器支路120a、120b分别包括三个串联的并联谐振器。
具体地，如图10所示，对于并联支路120a而言，包括串联于第一节点Nout与接地端GND之间的第一并联谐振器PR1、第二并联谐振器PR2、第三并联谐振器PR3；对于并联支路120b而言，包括串联于第一节点Nout与接地端GND之间的第四并联谐振器PR4、第五并联谐振器PR5以及第六并联谐振器PR6。
更为具体地，第一并联谐振器PR1包括第一极性的第一电极PR1T与第二极性的第二电极PR1B，第二并联谐振器PR2包括第一极性的第三电极PR2T与第二极性的第四电极PR2B，第三并联谐振器PR3包括第一极性的第五电极PR3T与第二极性的第六电极PR3B。
其中，第一电极PR1T连接于第一节点Nout，第二电极PR1B连接于第三电极PR2T，第四电极PR2B连接于第五电极PR3T，第六电极PR3B连接接地端GND。
第四并联谐振器PR4包括第七电极PR4T与第八电极PR4B，第五并联谐振器PR5包括第九电极PR5T与第十电极PR5B，第六并联谐振器PR6包括第十一电极PR6T与第十二电极PR6B。
其中，第七电极PR4T连接于输出端Out，第八电极PR4B连接于第九电极PR5T，第十电极PR5B连接于第十一电极PR6T，第十二电极PR6B连接诶于接地端GND。
其中，每个并联谐振支路120a、120b中排列在第一位置并联谐振器中相同极性的电极连接输出端Out。本实施例中，每个并联谐振支路120a、120b中排列在第一位置第一极性的第一电极PR1T、第七电极PR4T连接第一节点Nout，同时，每个并联谐振支路120a、120b中排列在第末位置第二极性的第六电极PR3B、第十二电极PR6B连接接地端GND。
在本申请其他实施例中，每个并联谐振支路120a、120b中排列在第一位置第一极性的第一电极PR1T、第七电极PR4T连接接地端GND，同时，每个并联谐振支路120a、120b中排列在第末位置第二极性的第六电极PR3B、第十二电极PR6B连接第一节点Nout。
本实施例中，并联谐振器单元120中每个并联谐振器支路由于包含有三个串联的并联谐振器，那么，就能够进一步针对射频信号进行分压，从而进一步降低了每个并联谐振器上的电压与功率，从而能够进一步降低滤波电路100所产生的互调产物(PIM干扰信号)。本实施例中，并联谐振器单元120中包括的并联谐振支路120a、120b分别串联的三个并联谐振器，能够使得无源互调中的PIM3(3rd Passive Inter Modulation，三阶互调)得到有效提升，因为滤波电路PIM3是PIM干扰的主要构成，当PIM3干扰被抑制后，滤波电路100整体产生的干扰得到有效抑制，保证了针对无线射频信号滤波后的品质。
请参阅图11，其为本申请又一实施例中图1所示滤波电路400的电路结构示意图。本实施例中，滤波电路400与图9所示滤波电路200的结构基本相同，区别仅在于，滤波电路300中，第一并联谐振器单元120包括的并联谐振器支路的数量M为3，每个并联谐振 器支路中包括的并联谐振器的数量N为2。也即是第一并联谐振器单元120包括三个并联谐振器支路，每一个并联谐振器支路包含两个串联的并联谐振器。
具体地，如图11所示，第一并联谐振器单元120包括至少三个相互并联的并联谐振器支路120a、120b、120c。其中，图11所示的并联谐振器支路120a、120b的电路结构、连接方式与图4所示的并联谐振器支路120a、120b的电路结构、连接方式相同，本实施例不再赘述。
对于并联谐振器支路120c而言，包括串联于输出端Out与接地端GND之间的第七并联谐振器PR7与第八并联谐振器PR8。
其中，第七并联谐振器PR7包括第一极性的第十三电极PR7T与第二极性的第十四电极PR7B，第八并联谐振器PR8包括第一极性的第十五电极PR8T与第二极性的第十六电极PR2B。
其中，第十三电极PR7T连接于最邻近输出端Out的节点Nout，第十四电极PR7B连接于第十五电极PR8T，第十六电极PR2B连接于接地端GND。
本实施例中，并联谐振器单元120中包括的并联谐振支路120a、120b、120c分别串联的两个并联谐振器，由此，并联谐振器单元120由于包含有三个并联谐振器支路，那么，就能够进一步针对射频信号进行分流，从而进一步降低了每个并联谐振器上的电流与功率，能够使得无源互调中的PIM3(3rd Passive Inter Modulation，三阶互调)进一步得到提升，滤波电路100整体产生的干扰得到有效抑制，保证了针对无线射频信号滤波后的品质。
以上对本申请实施例所提供的一种提高无源互调的滤波器进行了详细介绍，本文中应用了具体个例对本申请的原理及实施例进行了阐述，以上实施例的说明只是用于帮助理解本申请的方法及其核心思想；同时，对于本领域的一般技术人员，依据本申请的思想，在具体实施例及应用范围上均会有改变之处，综上所述，本说明书内容不应理解为对本申请的限制。

Claims (11)

  1. 一种滤波电路，其特征在于，包括输入端、串联谐振器单元、并联谐振单元与输出端，
    所述输入端用于接收射频信号；
    所述串联谐振器单元连接于所述输入端与所述输出端之间；
    所述并联谐振器单元包括M个相互并联的并联谐振器支路，所述M个并联谐振器支路均连接于所述输入端与所述输出端之间第一节点与接地端之间，且所述M个并联谐振器之路中的每一个并联谐振器支路包括至少一个并联谐振器，所述并联谐振器单元为距离所述输出端最近一级的并联谐振器单元，M为大于或者等于2的自然数，所述串联谐振器单元与所述并联谐振器单元配合针对所述射频信号执行滤波后从所述输出端输出；
    每一个并联谐振器包括第一极性的第一电极与第二极性的第二电极，其中，
    所述每一个并联谐振器支路中连接于所述第一节点的电极均为第一极性的第一电极；或者，
    每一个并联谐振器支路中连接于所述第一节点的电极均为第二极性的第二电极。
  2. 根据权利要求1所述的滤波电路，其特征在于，当每一个所述并联谐振器支路包括两个或两个以上谐振器时，所述两个或者两个以上并联谐振器相互串联。
  3. 根据权利要求2所述的滤波电路，其特征在于，当每一个所述并联谐振器支路包括N个谐振器时，所述N为2，每一个所述并联谐振器支路包括的两个并联谐振器串联，所述N为大于或者等于2的自然数。
  4. 根据权利要求2所述的滤波电路，其特征在于，当每一个所述并联谐振器支路包括N个谐振器时，所述N为3，每一个所述并联谐振器支路包括的三个并联谐振器串联，所述N为大于或者等于2的自然数。
  5. 根据权利要求1所述的滤波电路，其特征在于，每一个所述并联谐振器支路中串联的并联谐振器数量不相同。
  6. 根据权利要求1-5任意一项所述的滤波电路，其特征在于，所述串联谐振器单元在反谐振频率处呈现高阻抗特性，所述并联谐振器单元在谐振频率处呈现高阻抗特性，所述串联谐振器单元与所述并联谐振器单元构成带通滤波器，所述带通滤波器的中心频率为所述串联谐振器单元的谐振频率或者为所述并联谐振器单元的反谐振频率。
  7. 根据权利要求6所述的滤波电路，其特征在于，所述滤波电路为表面声波滤波器。
  8. 根据权利要求6所述的滤波电路，其特征在于，所述滤波电路为体声波滤波器。
  9. 一种双工器，其特征在于，包括两个如权利要求1-8任意一项所述的滤波器，所述两个滤波器分别在射频信号接收方向与射频信号发送方向针对射频信号执行滤波。
  10. 一种通信装置，其特征在于，包括权利要求1-8任意一项所述的滤波电路。
  11. 根据权利要求10所述的通信装置，其特征在于，还包括天线，所述天线与所述滤波电路连接。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115986345A (zh) * 2022-11-30 2023-04-18 北京芯溪半导体科技有限公司 一种改善非线性特性的滤波器、双工器和多工器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080055021A1 (en) * 2006-09-01 2008-03-06 Fujitsu Media Limited Acoustic wave device, filter and duplexer
CN102611410A (zh) * 2011-01-19 2012-07-25 太阳诱电株式会社 双工器
CN104253592A (zh) * 2013-06-27 2014-12-31 太阳诱电株式会社 双工器
CN106253876A (zh) * 2015-06-09 2016-12-21 太阳诱电株式会社 梯型滤波器、双工器以及模块
CN107078719A (zh) * 2014-09-03 2017-08-18 追踪有限公司 具有改善的线性的滤波器

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4030795B2 (ja) * 2002-05-09 2008-01-09 日本電波工業株式会社 弾性表面波デバイス
JP5394847B2 (ja) * 2009-08-06 2014-01-22 太陽誘電株式会社 分波器
JP5942740B2 (ja) * 2012-09-25 2016-06-29 株式会社村田製作所 ラダー型フィルタ及び分波器
US9246533B2 (en) * 2012-10-18 2016-01-26 Skyworks Panasonic Filter Solutions Japan Co., Ltd. Electronic device including filter
US20160191015A1 (en) * 2014-12-27 2016-06-30 Avago Technologies General Ip (Singapore) Pte. Ltd. Split current bulk acoustic wave (baw) resonators
WO2016174938A1 (ja) * 2015-04-30 2016-11-03 株式会社村田製作所 ラダー型フィルタ及びデュプレクサ
CN108604893B (zh) * 2016-02-08 2022-06-17 株式会社村田制作所 高频滤波电路、双工器、高频前端电路以及通信装置
CN109643989B (zh) * 2016-09-02 2023-03-21 株式会社村田制作所 弹性波滤波器装置、高频前端电路以及通信装置
WO2018123775A1 (ja) * 2016-12-26 2018-07-05 株式会社村田製作所 弾性表面波装置および弾性表面波フィルタ
CN109639255B (zh) * 2018-12-25 2022-07-12 天津大学 一种双工器

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080055021A1 (en) * 2006-09-01 2008-03-06 Fujitsu Media Limited Acoustic wave device, filter and duplexer
CN102611410A (zh) * 2011-01-19 2012-07-25 太阳诱电株式会社 双工器
CN104253592A (zh) * 2013-06-27 2014-12-31 太阳诱电株式会社 双工器
CN107078719A (zh) * 2014-09-03 2017-08-18 追踪有限公司 具有改善的线性的滤波器
CN106253876A (zh) * 2015-06-09 2016-12-21 太阳诱电株式会社 梯型滤波器、双工器以及模块

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4057507A4

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115986345A (zh) * 2022-11-30 2023-04-18 北京芯溪半导体科技有限公司 一种改善非线性特性的滤波器、双工器和多工器
CN115986345B (zh) * 2022-11-30 2024-02-06 北京芯溪半导体科技有限公司 一种改善非线性特性的滤波器、双工器和多工器

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