JP2018170755A - High frequency circuit and communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high frequency circuit that has a simple configuration, can transmit and receive signals at a plurality of bands in frequency bands different from each other at the same time, and can increase the steepness of an attenuation slope in a transition band of a pass characteristic.SOLUTION: A high frequency circuit 1 includes: a first circuit 10 including a first HPF 11 and a first LPF 12; and a second circuit 20 connected in series with the first circuit 10 and including a BEF 21 and a BPF 22. At least one of the BEF 21 and the BPF 22 includes an elastic wave resonator. An attenuation band of the BEF 21 and a pass band of the BPF 22 are situated between a pass band of the first HPF 11 and a pass band of the first LPF 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a high frequency circuit and a communication device.

  In recent years, communication devices such as mobile phone terminals have been required to simultaneously transmit and receive in a plurality of frequency bands and a plurality of wireless systems in one terminal, that is, to cope with so-called carrier aggregation (CA). In a communication apparatus that employs such a method, for example, a demultiplexing / multiplexing circuit that separates (demultiplexes) and combines (combines) high-frequency signals for each frequency band is used. Specifically, a circuit as shown in FIG. 19 is used. FIG. 19 is a configuration diagram showing an example of a conventional branching circuit.

  FIG. 19 shows a branching circuit in which a plurality of (for example, two) diplexers each composed of an LC resonance circuit are connected in series. In the branching circuit, the high-frequency signal input to the terminal Port 41 is passed through a passband of the HPF and LPF by a diplexer 401 including a high-pass filter (hereinafter also referred to as HPF) and a low-pass filter (hereinafter also referred to as LPF). Is demultiplexed into a signal of a frequency band corresponding to A signal output from the LPF of the diplexer 401 is demultiplexed into a signal in a frequency band corresponding to the passband of the HPF and LPF by a diplexer 402 configured by the HPF and LPF. Accordingly, according to the passband of the LPF of the diplexer 401 and the LPF of the diplexer 402 connected in series, the passband of the LPF of the diplexer 401 and the HPF of the diplexer 402 connected in series, and the passband of the HPF of the diplexer 401 Are output from terminals Ports 42 to 44, respectively.

  Patent Document 1 discloses a technique related to such a branching circuit.

JP 2011-91862 A

  However, in the branching circuit shown in FIG. 19, since the steepness of the attenuation slope located in the transition band in the pass characteristics of the diplexers 401 and 402 is low (the attenuation slope is small), signals having close pass frequency bands are mutually connected. Difficult to split. In order to improve this, it is conceivable to increase the steepness of the attenuation slope located in the transition band in the pass characteristic of the diplexer. However, in general, the design difficulty for increasing the steepness of the attenuation slope located in the transition band in the pass characteristic of the diplexer is high.

  Therefore, the present invention is a high-frequency circuit that can simultaneously transmit and receive signals of a plurality of bands of different frequency bands with a simple configuration, and can increase the steepness of the attenuation slope located in the transition band in the pass characteristics. And it aims at providing a communication apparatus.

  To achieve the above object, a high-frequency circuit according to an aspect of the present invention includes a first circuit that includes a first high-pass filter and a first low-pass filter, and demultiplexes or multiplexes a high-frequency signal; A second circuit that is connected in series to the first circuit, includes a band elimination filter and a band pass filter, and demultiplexes or multiplexes a high-frequency signal; and the band elimination filter and the band pass filter At least one of which is constituted by an elastic wave resonator, and the pass band of the first high-pass filter is located higher than the pass band of the first low-pass filter, and the band elimination The attenuation band of the filter and the pass band of the band pass filter are the pass band of the first high pass filter and the pass of the first low pass filter. Located between the band.

  The first HPF has a wide passband on the high frequency side, the first LPF has a wide passband on the low frequency side, and the passband of one or more bandpass filters (hereinafter also referred to as BPF) is: It is located between the passband of the first HPF and the passband of the first LPF. The first circuit including the first HPF and the first LPF and the second circuit including the BPF are connected in series, so that signals in a plurality of bands in different frequency bands can be simultaneously transmitted and received. It becomes possible. In other words, it is possible to cope with CA conversion from a signal having a low frequency band to a signal having a high frequency band. Here, the band is, for example, an LTE (Long Term Evolution) band. Further, since the band elimination filter (hereinafter also referred to as “BEF”) and the BPF are composed of elastic wave resonators, the steepness of the attenuation slope located in the transition band in the pass characteristic is high. Therefore, for example, a signal having a frequency component in the BPF passband and a signal having a frequency component in the first HPF passband or the first LPF passband are less likely to affect each other. Further, when the BPF includes two or more BPFs, signals having frequency components in the passbands of the two or more BPFs do not easily affect each other. As described above, signals of a plurality of bands having different frequency bands are obtained with a simple configuration in which the first circuit including the first HPF and the first LPF and the second circuit including the BEF and the BPF are connected in series. Can be transmitted and received simultaneously, and the steepness of the attenuation slope located in the transition band in the pass characteristic can be increased.

  The first high-pass filter and the first low-pass filter have a common first common terminal, and the first common terminal and a terminal of the band elimination filter are connected in series, and the band elimination is performed. The filter and the bandpass filter have a common second common terminal, and the attenuation slope in the transition band of the pass characteristic of the band elimination filter is an attenuation slope in the transition band of the pass characteristic of the first highpass filter, and In addition, at least one of the attenuation slopes in the transition band of the pass characteristic of the first low-pass filter may be attenuated.

  Accordingly, the attenuation slope of the first HPF having a low steepness is attenuated by the attenuation slope having a high BEF steepness in the transition band on the high frequency side of the BEF, and the steepness of the attenuation slope is increased. Similarly, for example, the attenuation slope of the first LPF having a low steepness in the transition band on the low frequency side of the BEF is attenuated by the attenuation slope having a high BEF steepness, and the steepness of the attenuation slope is increased. Therefore, the signal having the frequency component of the pass band of the BPF and the signal having the frequency component of the pass band of the first HPF or the first LPF are less likely to influence each other. That is, signals having close pass frequency bands can be easily demultiplexed / multiplexed.

  The first circuit further includes a second high-pass filter, the band elimination filter and the band-pass filter have a common terminal, and the common terminal and the terminal of the second high-pass filter And the pass band of the second high-pass filter is located between the pass band of the first high-pass filter and the pass band of the first low-pass filter, and the pass band of the second high-pass filter The band, the pass band of the band pass filter, and the attenuation band of the band elimination filter may overlap.

  As a result, the BEF attenuation band and the BPF pass band overlap, so that the signal having the frequency component of the BPF pass band and the frequency component of the second HPF pass band excluding the BEF attenuation band are included. Signals are less likely to affect each other. Further, a part of the pass band of the second HPF is attenuated by the attenuation slope having a high BEF steepness, so that the steepness of the attenuation slope of the second HPF and the BEF connected in series is increased.

  The first circuit further includes a second low-pass filter, the second high-pass filter and the first low-pass filter are connected to the second low-pass filter, and the high-frequency circuit is a third high-pass filter. The filter may further include a filter and a third low-pass filter, the third high-pass filter and the third low-pass filter may be connected to the first high-pass filter, and the high-frequency circuit may be a pentaplexer.

  According to this configuration, it is possible to perform carrier aggregation that simultaneously transmits, receives, or both five signals having passbands of different frequency bands.

  The second branching circuit may further include a band pass filter or a high pass filter, and the high frequency circuit may be a hex suppressor.

  According to this configuration, it is possible to perform carrier aggregation in which six signals having passbands having different frequency bands are simultaneously transmitted, received, or both.

  A high-frequency circuit according to one embodiment of the present invention includes a first circuit including a second high-pass filter and a first low-pass filter, and is connected in series to the first circuit, and includes a band elimination filter and a band A second circuit including a pass filter, wherein at least one of the band elimination filter and the band pass filter includes an elastic wave resonator, and a pass band of the second high pass filter Is located higher than the pass band of the first low-pass filter, and the attenuation band of the band elimination filter and the pass band of the band-pass filter are more than the pass band of the first low-pass filter. Is also located on the high frequency side and overlaps the pass band of the second high pass filter.

  The first LPF has a wide pass band on the low frequency side, and the pass band of one or more BPFs is located on the high frequency side with respect to the pass band of the first LPF. Since the first circuit including the first LPF and the second circuit including the BPF are connected in series, transmission and reception can be performed simultaneously in a plurality of bands having different frequency bands. Moreover, since BEF and BPF are comprised by the elastic wave resonator, the steepness of the attenuation slope located in the transition band in a passage characteristic is high. Therefore, a signal having a frequency component in the passband of the BPF and a signal having a frequency component in the passband of the first LPF are less likely to affect each other. Further, a part of the pass band of the second HPF is attenuated by the attenuation slope having a high BEF steepness, so that the steepness of the attenuation slope of the second HPF and the BEF connected in series is increased. Accordingly, since the BEF attenuation band and the BPF pass band overlap, the signal having the frequency component of the BPF pass band and the signal having the frequency component of the band excluding the BEF attenuation band of the second HPF pass band. And are less likely to affect each other. Further, when the BPF includes two or more BPFs, signals having frequency components in the passbands of the two or more BPFs do not easily affect each other. As described above, signals of a plurality of bands having different frequency bands are obtained with a simple configuration in which the first circuit including the second HPF and the first LPF and the second circuit including the BEF and the BPF are connected in series. Can be transmitted and received simultaneously, and the steepness of the attenuation slope located in the transition band in the pass characteristic can be increased.

  The high frequency circuit may be a triplexer.

  According to this configuration, it is possible to perform carrier aggregation in which three signals having passbands having different frequency bands are transmitted, received, or both at the same time.

  The second circuit may further include a high pass filter, and the high frequency circuit may be a quadplexer.

  According to this configuration, it is possible to simultaneously transmit and receive signals of a plurality of bands of different frequency bands, and it is possible to increase the steepness of the attenuation slope located in the transition band in the pass characteristics. In addition, carrier aggregation in which four signals having passbands of different frequency bands are simultaneously transmitted, received, or both can be performed.

  The second circuit may further include a band pass filter, and the high frequency circuit may be a quadplexer.

  According to this configuration, it is possible to perform carrier aggregation in which four signals having passbands of different frequency bands are transmitted, received, or both at the same time.

  Further, the attenuation amount of the pass band in the band corresponding to the first low-pass filter in the second high-pass filter is 15 dB or more, compared with the case where the first low-pass filter is not provided, The high pass filter may be composed of an inductor and a capacitor, and the first low pass filter may be composed of an inductor and a capacitor.

  According to this configuration, distortion can be effectively suppressed.

  A high-frequency circuit according to one embodiment of the present invention includes a first circuit that includes a second high-pass filter, and a second circuit that is connected in series to the first circuit and includes a band elimination filter and a band-pass filter. And comprising. At least one of the band elimination filter and the band pass filter includes an elastic wave resonator, and the attenuation band of the band elimination filter and the pass band of the band pass filter are the second band The band elimination filter is a hybrid filter composed of at least one elastic wave resonator and at least one inductor, and the high frequency circuit simultaneously transmits and receives a plurality of signals. Or a multiplexer that performs both.

  According to this configuration, it is possible to perform carrier aggregation in which two signals having passbands of different frequency bands are simultaneously transmitted, received, or both, and a high frequency signal of HB (High Band) and a high frequency of MB (Middle Band). It is applicable to 4 × 4 multiple-input and multiple-output using signals (so-called 4 × 4 MIMO, a technique for transmitting and receiving data simultaneously using four antennas for transmission and reception).

  The first circuit further includes a first high-pass filter and a second low-pass filter, the second high-pass filter is connected to the second low-pass filter, and the high-frequency circuit is a third high-pass filter. And a third low-pass filter, and the third high-pass filter and the third low-pass filter may be connected to the first high-pass filter.

  According to this configuration, it is possible to perform carrier aggregation in which four signals having passbands having different frequency bands are transmitted, received, or both at the same time, and a high-frequency signal of LTE-U and a high frequency of UHB (Ultra High Band). 4x4 multiple-input and multiple-output using signals, HB high-frequency signals, and MB high-frequency signals (so-called 4x4 MIMO, for transmission and reception, each using four antennas for simultaneous transmission and reception of data) Technology).

  Further, a matching circuit connected between the second high-pass filter and the second circuit may be further included.

  According to this configuration, impedance matching becomes possible, and as a result, pass characteristics can be improved.

  The matching circuit may be composed of at least one of an inductor and a capacitor.

  According to this configuration, it is possible to expect a further effective improvement of the pass characteristic.

  The band-pass filter includes a first band-pass filter and a second band-pass filter having different pass bands, and the matching circuit includes the first band-pass filter and the second band-pass filter. Of the first band pass filter and the second band pass filter, the pass band of the first band pass filter is the desired band elimination filter. The wiring located near the passband and connecting the matching circuit and the first bandpass filter may be shorter than the wiring connecting the matching circuit and the second bandpass filter.

  Since the passband of the first BPF and the desired passband of the BEF are located close to each other, the first BPF tends to affect the BEF. For example, when the wiring connecting the matching circuit and the first BPF is long, the amount of adjustment in the impedance matching of the first BPF increases by the amount of impedance variation due to the wiring. Thereby, the BEF in which a desired pass band is located near the pass band of the first BPF is affected by impedance matching regarding the wiring. On the other hand, the second BPF is less likely to affect the BEF because the pass band is far from the desired pass band of the BEF. For example, even if the wiring connecting the matching circuit and the second BPF is long, the second BPF A BEF whose pass band is not located near the pass band of the second BPF is less susceptible to impedance matching related to the wiring. Therefore, since the wiring connecting the matching circuit and the first BPF is shorter than the wiring connecting the matching circuit and the second BPF, the first wiring by the wiring connecting the matching circuit and the first BPF is used. The amount of adjustment in impedance matching of the BPF can be reduced, and the influence of the BEF on the impedance matching of the first BPF can be reduced.

  The band pass filter may include a first band pass filter and a second band pass filter having different pass bands.

  As a result, transmission / reception of signals in more frequency bands becomes possible.

  The high-pass filter and low-pass filter included in the high-frequency filter may be an LC resonance circuit.

  Thereby, an HPF having a wide pass band on the high frequency side (for example, the first HPF) and an LPF having a wide pass band on the low frequency side (for example, the first LPF) can be easily realized, and the signal has a low frequency band. To a signal having a high frequency band. When the LC resonance circuit is realized by a single component such as a chip inductor and a chip capacitor, for example, flexible matching adjustment of the first HPF and the first LPF is possible. In addition, when the LC resonance circuit is realized by, for example, an IPD (Integrated Passive Device), the first HPF and the first LPF can be reduced in size.

  An inductor may be connected in parallel to the band pass filter.

  Generally, when the pass band of the BPF is widened, the attenuation amount outside the pass band becomes small. Therefore, when an inductor having an attenuation pole outside the pass band is connected in parallel to a BPF having a wide pass band, the amount of attenuation outside the pass band is caused by the parasitic capacitance component generated when the inductor and the inductor are connected. Can be increased.

  The high frequency circuit may further include a low noise amplifier circuit, and the first circuit and the low noise amplifier circuit may be formed on the same chip.

  As a result, the first circuit and the low noise amplifier (hereinafter also referred to as LNA) circuit are formed on the same chip (one-chip), whereby the high-frequency circuit can be downsized.

  The high-frequency circuit may further include a switch circuit, and the first circuit and the switch circuit may be formed on the same chip.

  As a result, the first circuit and the switch circuit are formed on the same chip, whereby the high-frequency circuit can be reduced in size.

  The high-frequency circuit includes a multilayer substrate formed by laminating a plurality of layers, and the high-pass filter and the low-pass filter included in the high-frequency filter are LC resonance circuits, respectively, and the band elimination filter and the band pass Each of the filters is a ladder-type surface acoustic wave filter, and the multilayer substrate includes a reference ground layer, a first layer, and a second layer that are the lowermost layers of the multilayer substrate. A reference ground pattern serving as a reference potential of the multilayer substrate is provided, and the first layer is provided with a ground pattern of the first circuit electrically connected to the reference ground pattern, and the second layer Includes a ground pattern of the second circuit electrically connected to the reference ground pattern, and the first layer includes the first layer It may be located on the reference ground layer side than the second layer.

  Here, the reference ground layer is a layer for connecting the ground of the high-frequency circuit to the ground of the substrate of the set manufacturer or the like when the high-frequency circuit is connected to the substrate of the set manufacturer or the like. In the multilayer substrate, the ground pattern formed in a layer far from the reference ground layer has a larger parasitic inductor component. Therefore, by providing the ground pattern of the ladder-type surface acoustic wave filter far from the reference ground pattern, the parasitic inductor component increases, and the attenuation characteristics outside the pass band of the ladder-type surface acoustic wave filter are improved. Therefore, the ground patterns of the BEF and BPF that are ladder-type surface acoustic wave filters included in the second circuit are the ground patterns of the first HPF and the first LPF that are LC resonance circuits included in the first circuit. By providing the second layer positioned farther from the reference ground layer than the first layer provided with the BEF and BPF attenuation characteristics outside the passband can be improved.

  The high-frequency circuit includes a multilayer substrate configured by laminating a plurality of layers, and further includes a third branching circuit that is an elastic wave filter, and the ground pattern of the second circuit and the third circuit The ground pattern of the branching circuit may be provided separately from each other in one of the plurality of layers.

Thereby, it can suppress that a 2nd circuit and a 3rd branching circuit influence each other.

The band elimination filter may be a hybrid filter including at least one elastic wave resonator and at least one inductor.

  According to this configuration, the steepness of the attenuation slope located in the transition band in the pass characteristics can be increased.

  The high-frequency circuit may be a multiplexer that transmits, receives, or both a plurality of signals simultaneously.

  According to this configuration, it is possible to perform carrier aggregation in which a plurality of signals having passbands of different frequency bands are simultaneously transmitted, received, or both.

  In addition, a part of the pass band of the band pass filter may overlap with a part of the attenuation band of the band elimination filter.

  According to this configuration, the insertion loss of the bandpass filter can be improved.

  Further, a part of a desired pass band of the band elimination filter may be lower than a pass band of the band pass filter.

  According to this configuration, for example, it is appropriate for carrier aggregation of MB and HB in LTE.

  The band elimination filter may include a low pass filter type circuit and a high pass filter type circuit connected in series to the low pass filter type circuit.

  With this configuration, the high-frequency circuit has the characteristics of a bandpass filter and can secure attenuation other than the passband.

  In addition, a communication device according to one embodiment of the present invention includes an RF signal processing circuit that processes a high-frequency signal transmitted and received by an antenna element, and the high-frequency signal that is transmitted between the antenna element and the RF signal processing circuit. And a high-frequency circuit.

  As a result, it is possible to provide a communication device that can simultaneously transmit and receive signals of a plurality of bands in different frequency bands with a simple configuration and can increase the steepness of the attenuation slope located in the transition band in the pass characteristics. .

  The high-frequency circuit and the communication device according to the present invention can simultaneously transmit and receive signals of a plurality of bands in different frequency bands, and can increase the steepness of the attenuation slope located in the transition band in the pass characteristics. .

1 is a configuration diagram illustrating an example of a high-frequency circuit according to a first embodiment. 3 is a circuit diagram illustrating an example of a BEF according to the first embodiment. FIG. 2 is a circuit diagram showing an example of a BPF according to Embodiment 1. FIG. 6 is a graph showing an example of pass characteristics in the first path of the high-frequency circuit according to the first embodiment. 6 is a graph illustrating an example of pass characteristics in a second path of the high-frequency circuit according to the first embodiment. 6 is a graph illustrating an example of pass characteristics in a third path of the high-frequency circuit according to the first embodiment. It is the figure which compared the passage characteristic of the 3rd path | route from the 1st path | route. 6 is a configuration diagram illustrating an example of a communication device according to a modification of the first embodiment. FIG. FIG. 10 is a perspective view showing an example of a laminated substrate according to a modification of the first embodiment. It is sectional drawing in the VIB-VIB line | wire of FIG. 6A. FIG. 3 is a configuration diagram illustrating an example of a high-frequency circuit according to a second embodiment. 6 is a diagram for explaining pass characteristics of a high-frequency circuit according to Embodiment 2. FIG. FIG. 6 is a layout diagram illustrating an example of a high-frequency circuit according to a second embodiment. It is a circuit diagram which shows an example of the circuit by which the inductor was connected in parallel with 2nd BPF. FIG. 10 is a configuration diagram illustrating an example of a communication device according to a modification of the second embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the high frequency circuit which concerns on other embodiment. It is a block diagram which shows an example of the conventional branching circuit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the embodiments and the drawings. It should be noted that each of the embodiments described below shows a comprehensive or specific example. The numerical values, the constituent elements, the arrangement of the constituent elements, the connection form, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. Among the constituent elements in the following embodiments, constituent elements not described in the independent claims are described as optional constituent elements. In addition, the size or ratio of components shown in the drawings is not necessarily strict.

(Embodiment 1)
[1.1 Configuration of high-frequency circuit]
First, the configuration of the high-frequency circuit 1 according to Embodiment 1 will be described with reference to FIGS. 1 to 2B.

  FIG. 1 is a configuration diagram illustrating an example of a high-frequency circuit 1 according to the first embodiment.

  The high-frequency circuit 1 includes a first circuit 10 that demultiplexes or multiplexes a high-frequency signal and a second circuit 20 that is connected in series to the first circuit 10 and demultiplexes or multiplexes the high-frequency signal. The first circuit 10 and the second circuit 20 each have a function of combining a plurality of signal paths through which high-frequency signals of different frequency bands propagate into one signal path, or one signal path of different frequency bands. This circuit has a function of dividing a plurality of signal paths through which a high-frequency signal propagates. The high-frequency circuit 1 includes terminals Port1 to Port4. High-frequency signals in different frequency bands propagate through signal paths that connect each of the terminals Port1 to Port3 and the terminal Port4. The high-frequency circuit 1 has a function of combining high-frequency signals input to the terminals Port1 to Port3 and outputting from the terminal Port4. The high frequency circuit 1 has a function of demultiplexing the high frequency signal input to the terminal Port4 and outputting the demultiplexed signal from the terminals Port1 to Port3. For example, an HB high-frequency signal propagates in a signal path connecting the terminal Port1 and the terminal Port4, an LB (Low Band) high-frequency signal propagates in a signal path connecting the terminal Port2 and the terminal Port4, and the terminal Port3 and the terminal Port4. The high frequency signal of MB propagates in the signal path connecting Port4. For example, here, HB is a frequency band of 2300 MHz to 2700 MHz, LB is a frequency band of 2100 MHz band, and MB is a frequency band of 2100 MHz to 2200 MHz. In addition, said frequency band is an example and this invention is applicable also to another frequency band. The high frequency circuit 1 is, for example, a circuit that collects signal paths respectively connected to the terminals Port1 to Port3 at the terminal Port4.

  The first circuit 10 includes a first HPF 11 and a first LPF 12. The pass band of the first HPF 11 is located higher than the pass band of the first LPF 12. The first HPF 11 and the first LPF 12 are, for example, LC resonance circuits. As a result, the first HPF 11 having a wide pass band on the high frequency side and the first LPF 12 having a wide pass band on the low frequency side can be easily realized, from a signal having a low frequency band to a signal having a high frequency band. It can correspond to CA conversion. However, the pass characteristics of the first HPF 11 and the first LPF 12 have low attenuation slope steepness.

  The first HPF 11 and the first LPF 12 are realized as discrete components such as a chip inductor and a chip capacitor as an LC resonance circuit. Further, the first HPF 11 and the first LPF 12 may be realized by an IPD, for example, as an LC resonance circuit. Thereby, the 1st HPF11 and the 1st LPF12 can be reduced in size. Note that the circuit configuration of the first HPF 11 and the first LPF 12 is a general circuit configuration in which an inductor and a capacitor are simply connected in series or in parallel, and thus illustration thereof is omitted.

  The second circuit 20 includes a BEF 21 and a BPF 22. At least one of the BEF 21 and the BPF 22 is composed of an elastic wave resonator. The acoustic wave resonator may be either a surface acoustic wave (SAW) resonator or a bulk acoustic wave (BAW) resonator. In the present embodiment, for example, both the BEF 21 and the BPF 22 are constituted by surface acoustic wave resonators. Detailed circuit configurations of the BEF 21 and the BPF 22 will be described later with reference to FIGS. 2A and 2B.

  In addition, the filter comprised with a SAW resonator is provided with the board | substrate and the IDT (Interdigital transducer) electrode. The substrate is a substrate having piezoelectricity at least on the surface. For example, the substrate may be composed of a laminated body such as a piezoelectric thin film provided on the surface, a film having a sound velocity different from that of the piezoelectric thin film, and a supporting substrate. For example, the board | substrate may have piezoelectricity in the whole board | substrate. In this case, the substrate is a piezoelectric substrate composed of one piezoelectric layer.

  The terminal Port1 is connected to the input terminal of the first HPF 11 having HB as a pass band. The terminal Port2 is connected to the input terminal of the first LPF 12 having LB as a pass band. The terminal Port3 is connected to the input terminal of the BPF 22 having MB as a pass band. The first HPF 11 and the first LPF 12 have a common first common terminal (output terminal), and the first common terminal and the input terminal of the BEF 21 are connected in series. That is, in the present embodiment, the first circuit 10 and the second circuit 20 being connected in series means that the first common terminal and the input terminal of the BEF 21 are connected in series. For example, the BEF 21 further filters the signal filtered by the first HPF 11 or the signal filtered by the first LPF 12.

  Further, the BEF 21 and the BPF 22 have a common second common terminal (output terminal), and for example, a signal filtered by the BEF 21 or the BPF 22 is output from the terminal Port4. That is, a signal filtered by the first HPF 11 and BEF 21 connected in series, the first LPF 12 and BEF 21 connected in series, or the BPF 22 is output from the terminal Port 4. As described above, the high-frequency circuit 1 combines a plurality of signal paths through which high-frequency signals in different frequency bands are propagated into one signal path. In the present embodiment, the route passing through the first HPF 11 and BEF 21 connected in series is the first route, the route passing through the first LPF 12 and BEF 21 connected in series is the second route, and the BPF 22 The route that passes is called the third route.

  The high frequency circuit 1 may be realized as a high frequency module or a semiconductor device in combination with other components. Further, the high frequency circuit 1 may be realized as an element of only the high frequency circuit 1 without being combined with other components. For example, when the high-frequency circuit 1 is realized as an element having only the high-frequency circuit 1, the first circuit 10 and the second circuit 20 may be formed integrally or may be formed separately.

  Next, detailed circuit configurations of the BEF 21 and the BPF 22 will be described with reference to FIGS. 2A and 2B.

  FIG. 2A is a circuit diagram showing an example of the BEF 21 according to the first embodiment.

  FIG. 2B is a circuit diagram showing an example of the BPF 22 according to the first embodiment.

  In the high frequency circuit of the present application, the BEF 21 includes at least one elastic wave resonator and at least one inductor. The elastic wave resonator behaves like a capacitor in the frequency region where the elastic wave is not excited. Therefore, the elastic wave resonator exhibits the same behavior as the LC filter in the frequency region where the elastic wave is not excited, and as an elastic wave filter in the region where the elastic wave is excited. Shows the behavior. For this reason, a filter including at least one elastic wave resonator and at least one inductor may be referred to as a hybrid filter. Specifically, as shown in FIG. 2A, the BEF 21 includes inductors 211s, 212s, and 213p, and surface acoustic wave resonators 211p, 212p, 213s, and 214s. The inductors 211 s and 212 s and the surface acoustic wave resonators 213 s and 214 s are connected in series to each other on a path (series arm) connecting the terminal Port5 and the terminal Port4. The terminal Port4 corresponds to the terminal Port4 shown in FIG. Although not shown in FIG. 1, the terminal Port5 is a terminal connected to the first circuit 10 of the BEF 21. The surface acoustic wave resonators 211p and 212p and the inductor 213p include inductors 211s and 212s, an inductor 212s and a surface acoustic wave resonator 213s, and connection points of the surface acoustic wave resonators 213s and 214s and a reference terminal. It is connected on the path (parallel arm) connecting (ground). A low-pass filter type circuit (LPF) in which a part of the pass band formed by the inductors 211s and 212s and the surface acoustic wave resonators 211p and 212p is attenuated by the attenuation pole corresponding to the surface acoustic wave resonators 211p and 212p. Type circuit), surface acoustic wave resonators 213s and 214s, and inductor 213p, a part of the pass band is attenuated by attenuation poles corresponding to surface acoustic wave resonators 213s and 214s. The attenuation band of the BEF 21 is created by the circuit (HPF type circuit). By combining the LPF type circuit and the HPF type circuit, it becomes a characteristic of a band pass filter through which a high frequency signal passes except for the band to be attenuated, and attenuation outside the pass band can be ensured. With the above connection configuration, the BEF 21 that is a ladder-type surface acoustic wave filter is configured. Since the BEF 21 includes at least one surface acoustic wave resonator, the steepness of the attenuation slope located in the transition band in the pass characteristic is high.

  2B, the BPF 22 includes surface acoustic wave resonators 221s, 222s, 223s, 221p, and 222p. The surface acoustic wave resonators 221s, 222s, and 223s are connected in series to each other on a path (series arm) that connects the terminal Port3 and the terminal Port4. The terminal Port3 corresponds to the terminal Port3 shown in FIG. The surface acoustic wave resonators 221p and 222p are paths (parallel arms) that connect the surface acoustic wave resonators 221s and 222s and the connection points of the surface acoustic wave resonators 222s and 223s to the reference terminal (ground). Connected on top. With the above connection configuration, the BPF 22 which is a ladder type surface acoustic wave filter is configured. Since the BPF 22 is composed of a surface acoustic wave resonator, the steepness of the attenuation slope located in the transition band in the pass characteristic is high.

[1.2 Pass characteristics of high-frequency circuit]
Next, the pass characteristics of the high-frequency circuit 1 will be described with reference to FIGS. 3A to 4.

  FIG. 3A is a graph showing an example of pass characteristics in the first path of the high-frequency circuit 1 according to the first embodiment. 3A is a graph showing the pass characteristics of the first HPF 11 and the pass characteristics of the BEF 21, and FIG. 3A is a path (B) passing through the first HPF 11 and the BEF 21 connected in series. It is a graph which shows the passage characteristic of a 1st path | route. For example, when focusing on the first path, (b) of FIG. 3A schematically shows an insertion loss which is a ratio of the intensity of the signal output from the terminal Port4 to the intensity of the signal input to the terminal Port1. .

  The solid line shown in (a) of FIG. 3A shows the pass characteristic of the first HPF 11, and the broken line shows the pass characteristic of the BEF 21. The attenuation band of the BEF 21 is located on the lower frequency side than the pass band of the first HPF 11. Specifically, the attenuation slope (the portion where the pass characteristic is attenuated from the pass band on the high frequency side of the BEF 21 toward the attenuation band of the BEF 21) located in the transition band in the pass characteristic of the BEF 21 is the first HPF 11. An attenuation slope (a portion where the pass characteristic is attenuated from the pass band of the first HPF 11 toward the attenuation band of the first HPF 11) located in the transition band in the pass characteristic is attenuated. As a result, as shown in FIG. 3A (b), the attenuation slope located in the transition band in the pass characteristic of the first path becomes steep. In addition, in the vertical axis of the graph of the pass characteristics shown below including FIG. 3A, the insertion loss is assumed to be small on the upper side and large on the lower side. Further, since the first HPF 11 has a wide pass band on the high frequency side, the high frequency signal of HB in the wide frequency band on the high frequency side passes through the first path, and the high frequency signal of MB and LB is attenuated. Can do.

  FIG. 3B is a graph illustrating an example of pass characteristics in the second path of the high-frequency circuit 1 according to Embodiment 1. FIG. 3B is a graph showing the pass characteristics of the first LPF 12 and the pass characteristics of the BEF 21, and FIG. 3B is a path (B) passing through the first LPF 12 and the BEF 21 connected in series. It is a graph which shows the passage characteristic of a 2nd path | route.

  The solid line shown in (a) of FIG. 3B indicates the pass characteristic of the first LPF 12, and the broken line indicates the pass characteristic of the BEF 21. The attenuation band of the BEF 21 is located higher than the pass band of the first LPF 12. Specifically, the attenuation slope (the portion where the pass characteristic is attenuated from the low pass band of the BEF 21 toward the BEF 21 attenuation band) located in the transition band of the pass characteristic of the BEF 21 is the first LPF 12. The attenuation slope located in the transition band in the pass characteristic (the part where the pass characteristic is attenuated from the pass band of the first LPF 12 toward the attenuation band of the first LPF 12) is attenuated. Thereby, the attenuation slope located in the transition band in the pass characteristic of the first LPF 12 is attenuated by the BEF 21. At this time, since BEF21 has a high steepness of the attenuation slope located in the transition band in the pass characteristic, as shown in FIG. 3B (b), the attenuation slope located in the transition band in the pass characteristic of the second path is It will be steep. In addition, since the first LPF 12 has a wide pass band on the low frequency side, the LB high frequency signal in the wide frequency band on the low frequency side passes through the second path, and the high frequency signals of MB and HB are attenuated. Can do.

  FIG. 3C is a graph illustrating an example of pass characteristics in the third path of the high-frequency circuit 1 according to Embodiment 1.

  The solid line shown in FIG. 3C indicates the pass characteristic of the BPF 22. Since the BPF 22 has a high steepness of the attenuation slope located in the transition band in the pass characteristic, as shown in FIG. 3C, the attenuation slope located in the transition band in the pass characteristic of the path (third path) passing through the BPF 22 is It will be steep. In the third route, since the pass band of the BPF 22 is located between the pass band of the first HPF 11 and the pass band of the first LPF 12, a high frequency signal of MB corresponding to the pass band of the BPF 22 passes. The high frequency signals of LB and HB can be attenuated.

  3A to 3C are graphs having the same scale. Therefore, as shown in FIGS. 3A to 3C, the attenuation band of the BEF 21 and the pass band of the BPF 22 are located between the pass band of the first HPF 11 and the pass band of the first LPF 12. Furthermore, the attenuation slope located in the transition band in the pass characteristic of the BEF 21 is at least one of the attenuation slope in the transition band in the pass characteristic of the first HPF 11 and the attenuation slope located in the transition band in the pass characteristic of the first LPF 12. Is attenuated. Thereby, the attenuation slope of the first HPF 11 or the first LPF 12 having a low steepness is attenuated by the attenuation slope of the BEF 21 having a high steepness, and the steepness of the attenuation slope is increased in the first path or the second path. . Further, since the BPF 22 has a high steepness of the attenuation slope located in the transition band in the pass characteristic, the steepness of the attenuation slope increases in the third path.

  Next, in FIG. 4, the passage characteristics from the first route to the third route are compared.

  FIG. 4 is a diagram comparing the passage characteristics from the first route to the third route.

  As described above, the HB high-frequency signal propagates through the first path, the LB high-frequency signal propagates through the second path, and the MB high-frequency signal propagates through the third path. Since the first HPF 11 has a wide pass band on the high frequency side, the high-frequency signal of HB in the wide frequency band on the high frequency side passes through the first path. Since the first LPF 12 has a wide pass band on the low frequency side, the LB high frequency signal in the wide frequency band on the low frequency side passes through the second path. In the third route, since the pass band of the BPF 22 is located between the pass band of the first HPF 11 and the pass band of the first LPF 12, an MB high frequency signal corresponding to the pass band of the BPF 22 passes. Thus, the high frequency circuit 1 can cope with CA conversion of a signal in a wide frequency band from a low frequency side signal such as an LB signal to a high frequency signal side such as an HB signal.

  In addition, the attenuation slope located in the transition band in the pass characteristic of the first path is steep, and the attenuation slope located in the transition band in the pass characteristic of the third path is steep. The HB high-frequency signal passing through the first path and the MB high-frequency signal passing through the third path are less likely to affect each other. In addition, the attenuation slope located in the transition band in the pass characteristic of the second path is steep, and the attenuation slope located in the transition band in the pass characteristic of the third path is steep. The LB high-frequency signal passing through the second path and the MB high-frequency signal passing through the third path are less likely to affect each other.

  As described above, the first circuit 10 including the first HPF 11 and the first LPF 12 and the second circuit 20 including the BEF 21 and the BPF 22 are simply connected in series, and a plurality of different frequency bands are provided. It is possible to simultaneously transmit and receive signals in the band of the above-mentioned band and to increase the steepness of the attenuation slope located in the transition band in the pass characteristic.

(Modification of Embodiment 1)
The high-frequency circuit 1 according to the first embodiment includes only the first circuit 10 and the second circuit 20 that are the minimum necessary components, but the high-frequency circuit of the present invention further includes other components. May be. The high frequency circuit of the present invention can be applied to a communication device. Therefore, in the modification of the first embodiment, in addition to the first circuit 10 and the second circuit 20, the high-frequency circuit 1a including other components and the communication device 100 including the high-frequency circuit 1a will be described. .

[2.1 Communication device configuration]
A configuration of communication apparatus 100 according to a modification of the first embodiment will be described with reference to FIGS. 5 to 6B.

  FIG. 5 is a configuration diagram illustrating an example of the communication apparatus 100 according to a modification of the first embodiment. Note that FIG. 5 also illustrates an antenna element ANT that is not included in the components of the communication device 100.

  The communication device 100 includes a high-frequency circuit 1a and an RF signal processing circuit (RFIC: Radio Frequency Integrated Circuit) 80.

  The high-frequency circuit 1 a includes a first circuit 10, a second circuit 20, an LNA circuit 30, a switch circuit 40, a third circuit 50, and a switch IC (Integrated Circuit) 70. That is, the high frequency circuit 1 a further includes an LNA circuit 30, a switch circuit 40, a third circuit 50, and a switch IC 70 in addition to the components of the high frequency circuit 1. Since the first circuit 10 and the second circuit 20 are the same as those in the first embodiment, description thereof is omitted.

  The switch IC 70 has a common terminal connected to the antenna element ANT, and a plurality of selection terminals connected to input terminals of the multiplexers 51 and 55 included in the third circuit 50, for example. The switch IC 70 connects the common terminal and one of the plurality of selection terminals, for example, in accordance with a control signal from a control unit (not shown) included in the communication device 100, so that the antenna element ANT and each of the predetermined elements are respectively predetermined. One of the multiplexers 51 and 55 corresponding to the band is connected.

  The third circuit 50 is a circuit that demultiplexes or multiplexes high-frequency signals, and includes, for example, BPFs 52 to 54 and BPFs 56 to 58 that are surface acoustic wave filters. The BPFs 52 to 54 constitute a multiplexer 51, and the BPFs 56 to 58 constitute a multiplexer 55. The multiplexers 51 and 55 are triplexers here, but may be duplexers or quadplexers. The passbands of the BPFs 52 to 54 and the BPFs 56 to 58 are not particularly limited. For example, BPFs 52 and 56 are HB passbands, BPFs 53 and 57 are LB passbands, and BPFs 54 and 58 are MB passbands.

  The switch circuit 40 includes switch ICs 41 to 43. For example, the first circuit 10 and the switch circuit 40 are formed on the same chip. As a result, the high-frequency circuit 1a can be miniaturized while the high-frequency circuit 1a is multifunctional, and the communication device 100 can be downsized. In this modification, the switch circuit 40 includes three switch ICs 41 to 43. However, the present invention is not limited to this, and two or less or four or more switch ICs are used depending on the number of bands handled by the communication device 100. You may have.

  The switch IC 41 has a plurality of selection terminals connected to the output terminals of the BPFs 52 and 56 included in the third circuit 50 and a common terminal connected to the input terminal of the LNA 31 included in the LNA circuit 30. For example, the switch IC 41 connects the common terminal and one of the plurality of selection terminals in accordance with a control signal from the control unit included in the communication apparatus 100, and thereby either the BPF 52 or 56 corresponding to the HB and the LNA 31. And connect.

  The switch IC 42 has a plurality of selection terminals connected to the output terminals of the BPFs 53 and 57 included in the third circuit 50 and a common terminal connected to the input terminal of the LNA 32 included in the LNA circuit 30. For example, the switch IC 42 connects either the BPF 53 or 57 corresponding to the LB and the LNA 32 by connecting the common terminal and any of the plurality of selection terminals according to a control signal from the control unit included in the communication device 100. And connect.

  The switch IC 43 has a plurality of selection terminals connected to the output terminals of the BPFs 54 and 58 included in the third circuit 50 and a common terminal connected to the input terminal of the LNA 33 included in the LNA circuit 30. The switch IC 43 connects, for example, the common terminal and one of the plurality of selection terminals in accordance with a control signal from the control unit included in the communication apparatus 100, so that one of the BPFs 54 and 58 corresponding to each MB and the LNA 33 And connect.

  The LNA circuit 30 includes LNAs 31 to 33, and is a reception amplification circuit that amplifies high-frequency signals such as HB, LB, and MB and outputs the amplified signals to the first circuit 10 and the second circuit 20, for example. For example, the first circuit 10 and the LNA circuit 30 are formed on the same chip. As a result, the high-frequency circuit 1a can be miniaturized while the high-frequency circuit 1a is multifunctional, and the communication device 100 can be downsized. In the present modification, the first circuit 10, the LNA circuit 30, and the switch circuit 40 are formed on the same chip, but any one of the LNA circuit 30 and the switch circuit 40 is connected to the first circuit 10. The same chip may be used. Further, neither the LNA circuit 30 nor the switch circuit 40 may be formed on the same chip as the first circuit 10.

  The RF signal processing circuit 80 performs signal processing on a high-frequency signal input from the antenna element ANT via the high-frequency circuit 1a by down-conversion or the like, and a received signal generated by the signal processing is, for example, a baseband signal processing circuit ( (Not shown).

  As described above, the high-frequency circuit of the present invention may be multifunctional and applied to a communication device.

  In the present embodiment, the high-frequency circuit 1a is applied to the reception path, but may be applied to the transmission path. In this case, a power amplifier (hereinafter also referred to as PA) circuit is disposed instead of the LNA circuit 30, and the first circuit 10 and the second circuit 20 are directly or indirectly connected to the antenna ANT, and the antenna ANT. Used to multiplex high-frequency signals into

[2.2 Multilayer substrate]
The high-frequency circuit 1a may include a laminated substrate 90 configured by laminating a plurality of layers. In the high-frequency circuit 1 a, for example, components are mounted on the uppermost layer or the lowermost layer of the multilayer substrate 90, components are embedded in the inner layer of the multilayer substrate 90, or wiring patterns are provided on each layer constituting the multilayer substrate 90. This is realized. Here, the laminated substrate 90 will be described with reference to FIGS. 6A and 6B.

  FIG. 6A is a perspective view showing an example of a laminated substrate 90 according to a modification of the first embodiment. In FIG. 6A, illustrations of components mounted on the multilayer substrate 90, wiring patterns provided on the multilayer substrate 90, and the like are omitted.

  6B is a cross-sectional view taken along line VIB-VIB in FIG. 6A. FIG. 6B shows a part of the wiring pattern provided in each layer constituting the laminated substrate 90.

  The multilayer substrate 90 includes a reference ground layer 91, a first layer 93, and a second layer 95 that are the lowermost layers of the multilayer substrate 90. Here, the reference ground layer 91 is the lowest layer of the multilayer substrate 90. The first layer 93 is located closer to the reference ground layer 91 than the second layer 95. That is, the first layer 93 is disposed above the reference ground layer 91, and the second layer 95 is disposed above the first layer 93.

  The reference ground layer 91 is provided with a reference ground pattern 92 that serves as a reference potential for the multilayer substrate 90. The reference ground layer 91 is a layer for connecting a reference ground pattern 92 serving as a reference potential of the high frequency circuit 1a to the ground of the mounting substrate when the high frequency circuit 1a is connected to the mounting substrate.

  The first layer 93 is provided with a ground pattern 94 of the first circuit 10 that is electrically connected to the reference ground pattern 92. The ground pattern 94 and the reference ground pattern 92 are electrically connected by, for example, an interlayer connection via. Since the ground pattern 94 and the reference ground pattern 92 are physically separated with another layer interposed therebetween, the ground pattern 94 has a parasitic inductor component.

  The second layer 95 is provided with a ground pattern 96 of the second circuit 20 that is electrically connected to the reference ground pattern 92. The ground pattern 96 and the reference ground pattern 92 are electrically connected by, for example, an interlayer connection via. Since the ground pattern 96 and the reference ground pattern 92 are physically separated with another layer interposed therebetween, the ground pattern 96 has a parasitic inductor component. However, since the first layer 93 is located closer to the reference ground layer 91 than the second layer 95, the ground pattern 96 has a larger parasitic inductor component than the ground pattern 94. Therefore, since the BEF 21 and the BPF 22 included in the second circuit 20 are ladder-type surface acoustic wave filters, the ground pattern 96 of the second circuit 20 is provided far from the reference ground layer 91, thereby causing a parasitic inductor component. Increases, and the attenuation characteristic outside the passband of the second circuit 20 is improved.

  The second layer 95 is provided with the ground pattern 97 of the third circuit 50 that is electrically connected to the reference ground pattern 92. That is, the ground pattern 96 and the ground pattern 97 are provided in one layer (second layer 95) of the plurality of layers constituting the multilayer substrate 90. The ground pattern 96 and the ground pattern 97 are provided separately from each other in the second layer 95. That is, the ground pattern 96 and the ground pattern 97 are not connected in the second layer 95. Thereby, it can suppress that the 2nd circuit 20 and the 3rd circuit 50 couple | bond together via the ground pattern 96 and the ground pattern 97, and there exist effects, such as an improvement of receiving sensitivity.

  By arranging the ground pattern in the multilayer substrate 90 such as the first circuit 10, the second circuit 20, and the third circuit 50 included in the high-frequency circuit 1a in this way, the high-frequency that achieves both attenuation characteristics and pass characteristics. The circuit 1a can be realized.

(Embodiment 2)
For example, the high-frequency circuit 1 according to the first embodiment collects a plurality of signal paths through which high-frequency signals in different frequency bands are propagated into one signal path, but the high-frequency circuit of the present invention has one signal path. It may be divided into a plurality of signal paths through which high-frequency signals in different frequency bands propagate. In the second embodiment, a high frequency circuit 2 that divides one signal path into a plurality of signal paths through which high frequency signals in different frequency bands are propagated will be described.

[3.1 Configuration of high-frequency circuit]
The configuration of the high-frequency circuit 2 according to Embodiment 2 will be described with reference to FIG.

  FIG. 7 is a configuration diagram illustrating an example of the high-frequency circuit 2 according to the second embodiment.

  The high frequency circuit 2 includes a first circuit 110 and a second circuit 120 connected in series to the first circuit 110. The high-frequency circuit 2 includes a third HPF 131 and a third LPF 132, and a matching circuit 140. The high frequency circuit 2 includes terminals Port11 to Port17. For example, an antenna element is connected to the terminal Port11. In addition, high-frequency signals in different frequency bands propagate through signal paths that pass through the terminals Port12 to Port17. In the present embodiment, the high frequency circuit 2 is applied to the reception path, and has a function of demultiplexing the high frequency signal input to the terminal Port11 and outputting the demultiplexed signal from the terminals Port12 to Port17. The high-frequency circuit 2 may be applied to the transmission path, and may have a function of combining high-frequency signals input to the terminals Port12 to Port17 and outputting from the terminal Port11.

  For example, an LTE-U (LTE-Unlicensed) high-frequency signal propagates through the signal path passing through the terminal Port12. For example, a high frequency signal of UHB propagates through the signal path passing through the terminal Port13. For example, a high-frequency signal of HB2 propagates through the signal path passing through the terminal Port14. For example, a high frequency signal of HB1 propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, an LB high-frequency signal propagates through the signal path passing through the terminal Port17. For example, LTE-U is a frequency band of 5 GHz band, UHB is a frequency band of 2700 MHz to 3800 MHz, HB2 is a frequency band of 2496 MHz to 2690 MHz, HB1 is a frequency band of 2300 MHz to 2400 MHz, and MB is 1710 MHz. The frequency band is ˜2170 MHz, and LB is the frequency band of 699 MHz to 960 MHz. In addition, said frequency band is an example and this invention is applicable also to another frequency band. The high-frequency circuit 2 is, for example, a circuit that branches a signal path connected to the terminal Port11 to each of the terminals Port12 to Port17.

  The first circuit 110 includes a first HPF 111, a second LPF 112, a second HPF 113, and a first LPF 114. The first HPF 111, the second LPF 112, the second HPF 113, and the first LPF 114 are, for example, LC resonance circuits. Accordingly, the first HPF 111 and the second HPF 113 having a wide pass band on the high frequency side, and the second LPF 112 and the first LPF 114 having a wide pass band on the low frequency side can be easily realized with a low frequency. It can cope with CA conversion from a signal having a band to a signal having a high frequency band. However, the pass characteristics of the first HPF 111, the second LPF 112, the second HPF 113, and the first LPF 114 have a low attenuation slope steepness. Note that the circuit configurations of the first HPF 111, the second LPF 112, the second HPF 113, and the first LPF 114 are general circuit configurations in which an inductor and a capacitor are connected in series or in parallel, and thus are not illustrated. .

  The second circuit 120 includes a BEF 123 and a BPF. In the present embodiment, the BPF includes a first BPF 121 and a second BPF 122 having different pass bands. At least one of the BEF 123, the first BPF 121, and the second BPF 122 is configured by an acoustic wave resonator. In the present embodiment, for example, all of the BEF 123, the first BPF 121, and the second BPF 122 are constituted by surface acoustic wave resonators. The circuit configuration of the BEF 123 is the same as the circuit configuration shown in FIG. 2A, for example, and the circuit configuration of the first BPF 121 and the second BPF 122 is the same as the circuit configuration shown in FIG.

  The high-frequency circuit 2 is a multiplexer that transmits and receives a plurality of signals simultaneously, or both.

  Note that a filter composed of a SAW resonator includes a substrate and an IDT electrode. The substrate is a substrate having piezoelectricity at least on the surface. For example, the substrate may be composed of a laminated body such as a piezoelectric thin film provided on the surface, a film having a sound velocity different from that of the piezoelectric thin film, and a supporting substrate. For example, the board | substrate may have piezoelectricity in the whole board | substrate. In this case, the substrate is a piezoelectric substrate composed of one piezoelectric layer.

  The first HPF 111 and the second LPF 112, the second HPF 113 and the first LPF 114, the third HPF 131 and the third LPF 132, and the first BPF 121, the second BPF 122, and the BEF 123 are respectively connected to a common terminal (input). Terminal). The output terminal of the first HPF 111 and the common terminal of the third HPF 131 and the third LPF 132 are connected. The output terminal of the second LPF 112 and the common terminal of the second HPF 113 and the first LPF 114 are connected. The output terminal of the second HPF 113 and the common terminal of the first BPF 121, the second BPF 122, and the BEF 123 are connected. In the present embodiment, the first circuit 110 and the second circuit 120 are connected in series to the output terminal of the second HPF 113 and the common terminal of the first BPF 121, the second BPF 122, and the BEF 123. Is connected. In the present embodiment, the output terminal of the second HPF 113 and the common terminal of the first BPF 121, the second BPF 122, and the BEF 123 are connected through the matching circuit 140.

  The matching circuit 140 is a circuit for impedance matching of the first BPF 121, the second BPF 122, and the BEF 123, and is connected to the first BPF 121 and the second BPF 122. The matching circuit 140 is, for example, a circuit including at least one of a shunt inductor, a shunt capacitor, a series-connected inductor, and a series-connected capacitor.

[3.2 Passage characteristics of high-frequency circuits]
Next, the pass characteristics of the high-frequency circuit 2 will be described with reference to FIG.

  FIG. 8 is a diagram for explaining pass characteristics of the high-frequency circuit 2 according to the second embodiment. FIG. 8A is a diagram schematically showing the passband (the attenuation band for BEF123) of each filter included in the high-frequency circuit 2. FIG. FIG. 8B is a diagram comparing the pass characteristics in the respective paths connecting the terminal Port11 of the high-frequency circuit 2 and the terminals Port12 to 17 respectively.

  As shown in FIG. 8A, the pass band of the first HPF 111 is positioned higher than the pass band of the second LPF 112, and the pass band of the third HPF 131 is the third LPF 132. The pass band of the first HPF 111 overlaps the pass band of the third LPF 132 and the pass band of the third HPF 131. As a result, the pass band in the path via the first HPF 111 and the third HPF 131 connected in series becomes LTE-U, and the path in the path via the first HPF 111 and the third LPF 132 connected in series. The bandwidth is UHB.

  The pass band of the second HPF 113 is located between the pass band of the first HPF 111 and the pass band of the first LPF 114, and the pass band of the second LPF 112 is the pass band of the first LPF 114 and the first pass band of the first LPF 114. 2 overlaps with the pass band of the HPF 113. Thereby, the passband in the path | route via the 2nd LPF112 connected in series and the 1st LPF114 becomes LB.

  The pass band of the second HPF 113, the pass band of the first BPF 121 and the second BPF 122, and the attenuation band of the BEF 123 overlap. As a result, the passband in the path passing through the second LPF 112, the second HPF 113, and the BEF 123 connected in series is MB. The passband in the path passing through the second LPF 112, the second HPF 113, and the first BPF 121 connected in series is HB1. The passband in the path passing through the second LPF 112, the second HPF 113, and the second BPF 122 connected in series is HB2. Note that the pass band of the first HPF 111 is positioned higher than the pass band of the first LPF 114, and the attenuation band of the BEF 123 and the pass band of the BPF (the first BPF 121 and the second BPF 122) are The HPF 111 is located between the pass band of the first LPF 114 and the pass band of the first LPF 114.

  With the above configuration, as shown in FIG. 8B, the high-frequency circuit 2 converts the signal of a wide frequency band from a low-frequency signal such as an LB signal to a high-frequency signal such as an LTE-U signal. It can correspond to. In addition, since the attenuation band of the BEF 123 overlaps the pass band (HB1) of the first BPF 121 and the pass band (HB2) of the second BPF 122, the pass band of the first BPF 121 and the pass band of the second BPF 122 are Of the pass band of the second HPF 113, it does not overlap with the band (MB) excluding the attenuation band of the BEF 123. Therefore, the signal having the frequency component of the pass band of the first BPF 121 or the second BPF 122 and the signal having the frequency component of the band (MB) excluding the attenuation band of the BEF 123 in the pass band of the second HPF 113 influence each other. It becomes difficult to give. Further, a part of the pass band of the second HPF 113 is attenuated by the attenuation slope having a high steepness of the BEF 123, so that the steepness of the attenuation slope of the second HPF 113 and the BEF 123 connected in series is shown in FIG. As shown in (b), the high band-side attenuation slope has a high steepness in the MB pass characteristics. Therefore, the high frequency signal of MB and the high frequency signal of HB1 are less likely to affect each other. Further, since the steepness of the attenuation slope of each of the first BPF 121 and the second BPF 122 is high, the high-frequency signal of HB1 and the high-frequency signal of HB2 are less likely to affect each other.

  As shown in FIG. 8A, a part of the pass band of the band pass filter (first BPF 121, second BPF 122, or both) is part of the band elimination filter (BEF 123) attenuation band. Duplicate. This structure improves the insertion loss of the bandpass filter.

  As shown in FIG. 8A, a part of the pass band which is a band other than the attenuation band of the band elimination filter (BEF 123) is a band pass filter (first BPF 121, second BPF 122, or both). ) Lower than the passband.

  In the high frequency circuit 2 according to the second embodiment, a band elimination filter (BEF123) is used. When this band elimination filter (BEF123) is composed of an LC filter, a wide passband can be realized. In LTE frequency allocation, the MB bandwidth is larger than the HB bandwidth. Therefore, by using a band elimination filter for an MB having a wide bandwidth and a bandpass filter for an HB having a narrower bandwidth than the MB, the high-frequency circuit 2 is configured as a circuit suitable for carrier aggregation of MB and HB in LTE. Become.

  Thus, the first circuit 110 including the first HPF 111, the second LPF 112, the first LPF 114, and the second HPF 113, and the second circuit 120 including the first BPF 121, the second BPF 122, and the BEF 123. Can be transmitted and received at the same time, and the steepness of the attenuation slope located in the transition band in the pass characteristics can be increased. .

[3.3 Positional Relationship between Matching Circuit and First BPF and Second BPF]
Next, the positional relationship between the matching circuit 140 and the first BPF 121 and the second BPF 122 will be described with reference to FIG.

  FIG. 9 is a layout diagram illustrating an example of the high-frequency circuit 2 according to the second embodiment. FIG. 9 schematically shows the arrangement of some components of the high-frequency circuit 2 on the substrate when the high-frequency circuit 2 is realized by a laminated substrate or the like. FIG. 9 shows a wiring 141 that connects the matching circuit 140 and the first BPF 121 and a wiring 142 that connects the matching circuit 140 and the second BPF 122.

  As shown in FIG. 8A, the pass band of the first BPF 121 out of the pass band of the first BPF 121 and the pass band of the second BPF 122 is the desired pass band of the BEF 123 (second In the pass band of the HPF 113, the BEF 123 is located in the vicinity of the range excluding the broken arrow (for example, the MB range in FIG. 8A). Therefore, the first BPF 121 is more likely to affect the BEF 123 than the second BPF 122. For example, when the wiring 141 connecting the matching circuit 140 and the first BPF 121 is long, the amount of adjustment in the impedance matching of the first BPF 121 performed by the matching circuit 140 is increased by the amount of impedance variation caused by the wiring 141. In this case, due to impedance matching with respect to the long wiring 141, the BEF 123 whose pass band is located near the pass band of the first BPF 121 is affected.

  On the other hand, since the pass band of the second BPF 122 is located farther from the desired pass band of the BEF 123 out of the pass band of the first BPF 121 and the pass band of the second BPF 122, the second BPF 122 Is less likely to affect the BEF 123 than the first BPF 121. Therefore, even if the wiring 142 connecting the matching circuit 140 and the second BPF 122 is long, the BEF 123 whose pass band is not located near the pass band of the second BPF 122 is caused by impedance matching related to the wiring 142. Not easily affected.

  Therefore, as shown in FIG. 9, the wiring 141 that connects the matching circuit 140 and the first BPF 121 is made shorter than the wiring 142 that connects the matching circuit 140 and the second BPF 122. Thereby, the adjustment amount in the impedance matching of the first BPF 121 by the wiring 141 can be reduced, and the influence of the BEF 123 on the impedance matching of the first BPF 121 can be reduced.

[3.4 Other features of high-frequency circuit]
Next, other features of the high-frequency circuit 2 will be described with reference to FIG.

  FIG. 10 is a circuit diagram showing an example of a circuit in which an inductor 150 is connected in parallel to the second BPF 122. Note that, as described above, the circuit configuration of the second BPF 122 is the same as the circuit configuration shown in FIG. The terminal Port14 corresponds to the terminal Port14 shown in FIG. Although not shown in FIG. 7, the terminal Port 18 is a terminal connected to the matching circuit 140 of the second BPF 122. Further, in FIG. 7, the illustration of the inductor 150 is omitted.

  Generally, when the pass band of the BPF is widened, the attenuation amount outside the pass band becomes small. Therefore, even when the passband of the BPF is widened, an inductor having an attenuation pole outside the passband is connected in parallel to the BPF, so that the parasitic generated when the inductor and the inductor are connected. The amount of attenuation outside the passband can be increased by the capacitive component.

  In the present embodiment, as shown in FIG. 8B, the pass band (HB2) of the second BPF 122 is wider than the pass band (HB1) of the first BPF 121. Therefore, as shown in FIG. 10, an inductor 150 is connected in parallel to the second BPF 122 having a wider pass band. As a result, it is possible to increase the attenuation outside the pass band, which is reduced by widening the pass band of the second BPF 122. The inductor 150 may be connected in parallel to the first BPF 121, or may be connected in parallel to each of the first BPF 121 and the second BPF 122.

(Modification of Embodiment 2)
The high-frequency circuit 2 according to the second embodiment includes the first circuit 110 and the second circuit 120 which are the minimum necessary components, but the high-frequency circuit of the present invention further includes other components. Also good. The high frequency circuit of the present invention can be applied to a communication device. Therefore, in the modification of the second embodiment, in addition to the first circuit 110 and the second circuit 120, the high-frequency circuit 2a including other components and the communication device 200 including the high-frequency circuit 2a will be described. .

[4.1 Configuration of communication device]
A configuration of communication apparatus 200 according to a modification of the second embodiment will be described with reference to FIG.

  FIG. 11 is a configuration diagram illustrating an example of a communication device 200 according to a modification of the second embodiment. Note that FIG. 11 also shows an antenna element ANT that is not included in the components of the communication device 200.

  The communication device 200 includes a high frequency circuit 2a and an RF signal processing circuit 190.

  The high frequency circuit 2 a includes a first circuit 110 and a second circuit 120, a third HPF 131, a third LPF 132, an LNA circuit 160, a switch circuit 170 and a third circuit 180. That is, the high frequency circuit 2 a includes an LNA circuit 160, a switch circuit 170, and a third circuit 180 in addition to the components of the high frequency circuit 2. Since the first circuit 110, the second circuit 120, the third HPF 131, and the third LPF 132 are the same as those in the second embodiment, description thereof is omitted.

  The third circuit 180 includes, for example, duplexers 181 to 184. The duplexer 181 is a filter that demultiplexes, for example, an LTE-U high-frequency signal. The duplexer 182 is a filter that demultiplexes, for example, a UHB high-frequency signal. The duplexer 183 is a filter that demultiplexes, for example, an MB high-frequency signal. The duplexer 184 is a filter that demultiplexes, for example, an LB high-frequency signal. The duplexers 181 to 184 can demultiplex a high frequency signal in a wide frequency band such as LTE-U into a high frequency signal in a specific narrow frequency band.

  The switch circuit 170 includes switch ICs 171 to 173. For example, the first circuit 110 and the switch circuit 170 are formed on the same chip. In the present modification, the switch circuit 170 includes the three switch ICs 171 to 173. However, the present invention is not limited to this, and two or less or four or more switch ICs are used depending on the number of bands handled by the communication device 200. You may have.

  The switch IC 171 has a plurality of selection terminals connected to the output terminals of the duplexers 181 and 182 included in the third circuit 180 and a common terminal connected to the input terminal of the LNA 161 included in the LNA circuit 160. The switch IC 171 connects the common terminal and any one of the plurality of selection terminals in accordance with a control signal from a control unit (not shown) included in the communication device 200, for example, so that the duplexer 181 corresponding to LTE-U. The LNA 161 is connected to either the filter that configures the filter or the filter that configures the duplexer 182 corresponding to UHB.

  The switch IC 172 includes a plurality of selection terminals connected to the output terminals of the duplexer 183 included in the first BPF 121 and the second BPF 122 included in the second circuit 120 and the LNA circuit 160 included in the LNA circuit 160. And a common terminal connected to the input terminal. The switch IC 172 corresponds to the first BPF 121 and HB2 corresponding to HB1 by connecting the common terminal and one of the plurality of selection terminals, for example, in accordance with a control signal from the control unit included in the communication device 200. The LNA 162 is connected to one of the filters constituting the duplexer 183 corresponding to the second BPF 122 and the MB.

  The switch IC 173 includes a plurality of selection terminals connected to the output terminal of the duplexer 184 included in the third circuit 180 and a common terminal connected to the input terminal of the LNA 163 included in the LNA circuit 160. The switch IC 173 connects any one of the filters constituting the duplexer 184 corresponding to the LB by connecting the common terminal and any of the plurality of selection terminals in accordance with a control signal from the control unit of the communication device 200, for example. Kana and LNA 163 are connected.

  The LNA circuit 160 includes LNAs 161 to 163 and is, for example, a reception amplification circuit that amplifies a high-frequency signal from LB to LTE-U and outputs the amplified signal to the RF signal processing circuit 190. For example, the first circuit 110 and the LNA circuit 160 are formed on the same chip. In the present modification, the first circuit 110, the LNA circuit 160, and the switch circuit 170 are formed on the same chip. However, any one of the LNA circuit 160 and the switch circuit 170 is connected to the first circuit 110. The same chip may be used. Further, neither the LNA circuit 160 nor the switch circuit 170 may be formed on the same chip as the first circuit 110.

  The RF signal processing circuit 190 performs signal processing on the high-frequency signal input from the antenna element ANT via the high-frequency circuit 2a by down-conversion or the like, and the received signal generated by the signal processing is, for example, a baseband signal processing circuit ( (Not shown).

  As described above, the high-frequency circuit of the present invention may be multifunctional and applied to a communication device.

  In the present embodiment, the high-frequency circuit 2a is applied to the reception path, but may be applied to the transmission path. In this case, a PA circuit is disposed in place of the LNA circuit 160, and the first circuit 110 and the second circuit 120 are used for multiplexing high-frequency signals to the antenna ANT.

(Other embodiments)
Although the high-frequency circuit and the communication device according to the embodiments have been described above, the present invention is not limited to the above-described embodiments.

  For example, in the first embodiment and its modification, the second circuit 20 includes one BPF 22, but the present invention is not limited to this, and may include a plurality of BPFs.

  Further, for example, in the second embodiment and the modification thereof, the second circuit 120 includes the first BPF 121 and the second BPF 122. However, the present invention is not limited to this, and one BPF or three or more BPFs are included. May be included.

  Further, for example, in the second embodiment and the modification thereof, the high-frequency circuit 2 (2a) includes the third HPF 131 and the third LPF 132. However, the present invention is not limited thereto, and these may not be included.

  Further, for example, in the second embodiment and the modification thereof, the inductor 150 is connected in parallel to the second BPF 122. However, the present invention is not limited to this, and the inductor 150 may not be connected.

  For example, in the second embodiment, the high-frequency circuit 2 includes the matching circuit 140. However, the present invention is not limited thereto, and the matching circuit 140 may not be included.

  Further, for example, in the second embodiment and the modification thereof, the first circuit 110 includes the second LPF 112. However, the present invention is not limited to this, and the second LPF 112 may not be included. That is, the first HPF 111, the second HPF 113, and the first LPF 114 may have a common terminal (input terminal). Furthermore, the first circuit 110 may not include the first HPF 111. Here, a high-frequency circuit in which the first circuit does not include the first HPF 111 and the second LPF 112 will be described with reference to FIG.

  FIG. 12 is a configuration diagram illustrating an example of a high-frequency circuit 2b according to another embodiment.

  As shown in FIG. 12, the high-frequency circuit 2 b includes a first circuit 110 a that includes a second HPF 113 and a first LPF 114. The high-frequency circuit 2b includes a second circuit 120a that is connected in series to the first circuit 110a and includes the BEF 123 and the BPF. Here, the BPF includes a first BPF 121 and a second BPF 122 having different pass bands. At least one of the BEF 123, the first BPF 121, and the second BPF 122 is configured by an acoustic wave resonator.

  The pass band of the second HPF 113 is positioned higher than the pass band of the first LPF 114, and the attenuation band of the BEF 123 and the pass bands of the first BPF 121 and the second BPF 122 are Is located higher than the pass band of the LPF 114 and overlaps the pass band of the second HPF 113. As a result, the pass characteristics in each path connecting the terminal Port 21 and the terminals Port 14 to 17 of the high-frequency circuit 2b are those obtained by removing UHB and LTE-U from those shown in FIG. 8B.

  In the high frequency circuit 2b of FIG. 12, one signal path is divided into four signal paths. That is, the high-frequency circuit 2b in FIG. 12 is a multiplexer and a quadplexer that divides one signal path into four signal paths.

  For example, a high-frequency signal of HB2 propagates through the signal path passing through the terminal Port14. For example, a high frequency signal of HB1 propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, an LB high-frequency signal propagates through the signal path passing through the terminal Port17. For example, HB2 is a frequency band of 2496 MHz to 2690 MHz, HB1 is a frequency band of 2300 MHz to 2400 MHz, MB is a frequency band of 1427 MHz to 2200 MHz, and LB is a frequency band of 452 MHz to 960 MHz. With this configuration, it is possible to perform carrier aggregation in which four signals having different frequency band pass bands are transmitted, received, or both at the same time.

  With the above configuration, the high-frequency circuit 2b can cope with CA conversion of a signal in a wide frequency band from an LB signal on the low frequency side to an HB2 signal on the high frequency side, for example. In addition, since the attenuation band of the BEF 123 overlaps the pass band (HB1) of the first BPF 121 and the pass band (HB2) of the second BPF 122, the pass band of the first BPF 121 and the pass band of the second BPF 122 are Of the pass band of the second HPF 113, it does not overlap with the band (MB) excluding the attenuation band of the BEF 123. Therefore, the signal having the frequency component of the pass band of the first BPF 121 or the second BPF 122 and the signal having the frequency component of the band (MB) excluding the attenuation band of the BEF 123 in the pass band of the second HPF 113 influence each other. It becomes difficult to give. Further, a part of the pass band of the second HPF 113 is attenuated by the attenuation slope of the BEF 123 having a high steepness, so that the steepness of the attenuation slope of the second HPF 113 and the BEF 123 connected in series is increased. Therefore, the high frequency signal of MB and the high frequency signal of HB1 are less likely to affect each other. Further, since the steepness of the attenuation slope of each of the first BPF 121 and the second BPF 122 is high, the high-frequency signal of HB1 and the high-frequency signal of HB2 are less likely to affect each other.

  In this way, the first circuit 110a including the second HPF 113 and the first LPF 114 and the second circuit 120a including the first BPF 121, the second BPF 122, and the BEF 123 are simply connected in series. With the configuration, it is possible to simultaneously transmit and receive signals of a plurality of bands of different frequency bands, and it is possible to increase the steepness of the attenuation slope located in the transition band in the pass characteristics.

  The attenuation in the band corresponding to the pass band of the first LPF 114 in the second HPF 113 is 15 dB or more compared to the case where the first low-pass filter (first LPF 114) is not provided, and the second HPF 113 May be composed of an inductor and a capacitor, and the first LPF 114 may be composed of an inductor and a capacitor. With the above configuration, distortion characteristics are improved. The following can be considered as this reason.

  Elastic wave resonators basically have poor distortion characteristics. When a high-frequency signal such as a transmission signal is applied, a harmonic (second harmonic, third harmonic, etc.) or intermodulation distortion (IMD2, IMD3) Such distortion occurs. The occurrence of distortion leads to deterioration of the reception sensitivity of the communication device, etc. Therefore, it is important in terms of communication quality not to generate distortion as much as possible.

  For example, in FIG. 12, when a low-band (LB) transmission signal, which is the pass band of the first LPF 114, is input from Port 17, the LB transmission signal is output to Port 21, and at the same time, some signals are second While being attenuated by the HPF 113, it goes around to the second circuit 120 a, and distortion occurs in the acoustic wave resonator included in the second circuit 120 a.

  Here, if the attenuation amount in the band corresponding to the pass band of the first LPF 114 in the second HPF 113 is 15 dB or more, the transmission signal of the LB reaching the second circuit 120a is effectively suppressed. Therefore, distortion generated in the second circuit 120a can be effectively suppressed.

  In particular, when the pass band of LB is 452-960 MHz and the pass band of the second circuit 120a is 1427-2690 MHz, the second and third harmonics of the LB partially overlap with the pass band of the second circuit 120a. In such a case, the communication sensitivity is deteriorated. Therefore, in such a frequency configuration, the attenuation amount in the band corresponding to the pass band of the first LPF 114 in the second HPF 113 is ensured to be 15 dB or more so that the LB signal does not reach the second circuit 120a as much as possible. It is extremely effective to do.

  The second HPF 113 and the first LPF 114 are preferably composed of an inductor and a capacitor, respectively. This is because inductors and capacitors are elements having good distortion characteristics.

  FIG. 13 is a configuration diagram illustrating an example of a high-frequency circuit 2c according to another embodiment.

  In the high-frequency circuit 2 c shown in FIG. 13, the second circuit 120 b further includes a high-pass filter (HPF 124) in addition to the BEF 123 and the first BPF 121.

  Further, the pass band of the second HPF 113 is positioned higher than the pass band of the first LPF 114, and the attenuation band of the BEF 123 and the pass bands of the first BPF 121 and the HPF 124 are the same as those of the first LPF 114. It is located higher than the pass band and overlaps the pass band of the second HPF 113. As a result, the pass characteristic in each path connecting the terminal Port 21 of the high-frequency circuit 2c and each of the ports Ports 14 to 17 is obtained by removing UHB and LTE-U from the one shown in FIG. 8B.

  With the above configuration, the high frequency circuit 2c can cope with CA conversion of a signal in a wide frequency band from a low frequency side signal such as an LB signal to a high frequency signal side such as an HB2. In addition, since the attenuation band of the BEF 123 overlaps the pass band (HB1) of the first BPF 121 and the pass band (HB2) of the HPF 124, the pass band of the first BPF 121 and the pass band of the HPF 124 pass through the second HPF 113. Of the bands, it does not overlap with the band (MB) excluding the attenuation band of BEF123. Therefore, a signal having a frequency component in the pass band of the first BPF 121 or the HPF 124 and a signal having a frequency component in a band (MB) excluding the attenuation band of the BEF 123 in the pass band of the second HPF 113 are unlikely to affect each other. Become. Further, a part of the pass band of the second HPF 113 is attenuated by the attenuation slope of the BEF 123 having a high steepness, so that the steepness of the attenuation slope of the second HPF 113 and the BEF 123 connected in series is increased. Therefore, the high frequency signal of MB and the high frequency signal of HB1 are less likely to affect each other. Further, since the steepness of the attenuation slope of each of the first BPF 121 and the HPF 124 is high, the high frequency signal of HB1 and the high frequency signal of HB2 are less likely to affect each other.

  As described above, the first circuit 110a including the second HPF 113 and the first LPF 114 and the second circuit 120b including the first BPF 121, the HPF 124, and the BEF 123 are simply connected in series. Signals of a plurality of bands having different frequency bands can be transmitted and received simultaneously, and the steepness of the attenuation slope located in the transition band in the pass characteristics can be increased.

  FIG. 14 is a configuration diagram illustrating an example of a high-frequency circuit 2d in which the second circuit 120c does not include the second BPF 122 but includes the first BPF 121. In the high-frequency circuit 2d of FIG. 14, one signal path is divided into three signal paths. That is, the high-frequency circuit 2d in FIG. 14 is a triplexer that divides one signal path into three signal paths. For example, in the high-frequency circuit 2d of FIG. 14, a high-frequency signal (HB high-frequency signal) in the frequency band 2300 MHz to 2690 MHz propagates to the signal path passing through the terminal Port15. For example, a high-frequency signal (MB high-frequency signal) having a frequency band of 1427 MHz to 2200 MHz propagates through a signal path passing through the terminal Port16. For example, a high-frequency signal (LB high-frequency signal) having a frequency band of 452 MHz to 960 MHz propagates through a signal path passing through the terminal Port17. With this configuration, it is possible to perform carrier aggregation in which three signals having different frequency band pass bands are transmitted, received, or both at the same time.

  Even when the high-frequency circuit 2d includes a high-pass filter (HPF 124) instead of the first BPF 121, the same operation and effect can be obtained.

  FIG. 15 illustrates a high-frequency circuit 2e in which the second circuit 120c does not include the second BPF 122, includes the first BPF 121, and does not include a matching circuit between the first circuit 110 and the second circuit 120c. It is a block diagram which shows an example.

  As shown in FIG. 15, the high-frequency circuit 2 e includes a first circuit 110 and a second circuit 120 c connected in series to the first circuit 110. The high-frequency circuit 2e includes a third HPF 131 and a third LPF 132.

  The first circuit 110 includes a first HPF 111, a second LPF 112, a second HPF 113, and a first LPF 114. The second circuit 120 c includes a BEF 123 and a first BPF 121.

  The high-frequency circuit 2e includes terminals Port11 to Port13 and Port15 to Port17. For example, an antenna element is connected to the terminal Port11. In addition, high-frequency signals in different frequency bands propagate through signal paths that pass through the terminals Port12, Port13, and Port15 to Port17. In the present embodiment, the high-frequency circuit 2e is applied to the reception path, and has a function of demultiplexing a high-frequency signal input to the terminal Port11 and outputting the demultiplexed signal from the terminals Port12, Port13, and Port15 to Port17. The high-frequency circuit 2e may be applied to the transmission path, and may have a function of combining the high-frequency signals input to the terminals Port12, Port13, and Port15 to Port17 and outputting from the terminal Port11.

  In the high frequency circuit 2e of FIG. 15, one signal path is divided into five signal paths. That is, the high-frequency circuit 2e in FIG. 15 is a pentaplexer that divides one signal path into five signal paths.

  For example, a high-frequency signal of LTE-U propagates through a signal path passing through the terminal Port12. For example, a high frequency signal of UHB propagates through the signal path passing through the terminal Port13. For example, a high-frequency signal of HB propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, an LB high-frequency signal propagates through the signal path passing through the terminal Port17. For example, LTE-U is a frequency band of 5 GHz band, UHB is a frequency band of 3400 MHz to 3800 MHz, HB is a frequency band of 2300 MHz to 2690 MHz, MB is a frequency band of 1427 MHz to 2200 MHz, and LB is 452 MHz. It is a frequency band of ˜960 MHz. In addition, said frequency band is an example and this invention is applicable also to another frequency band. The high-frequency circuit 2e is, for example, a circuit that branches a signal path connected to the terminal Port11 to each of the terminals Port12, Port13, and Port15 to Port17.

  With this configuration, it is possible to perform carrier aggregation in which five signals having different frequency band passbands are simultaneously transmitted, received, or both.

  FIG. 16 is a configuration diagram illustrating an example of a high-frequency circuit 2f that does not include a matching circuit between the first circuit 110 and the second circuit 120a.

  The high-frequency circuit 2f includes terminals Port11 to Port17. For example, an antenna element is connected to the terminal Port11. In addition, high-frequency signals in different frequency bands propagate through signal paths that pass through the terminals Port12 to Port17. In the present embodiment, the high-frequency circuit 2f is applied to the reception path, and has a function of demultiplexing a high-frequency signal input to the terminal Port11 and outputting the demultiplexed signal from the terminals Port12 to Port17. The high-frequency circuit 2f may be applied to the transmission path and may have a function of combining high-frequency signals input to the terminals Port12 to Port17 and outputting from the terminal Port11.

  In the high-frequency circuit 2f in FIG. 16, one signal path is divided into six signal paths. That is, the high-frequency circuit 2f in FIG. 16 is a hexaplexer that divides one signal path into six signal paths.

  For example, a high-frequency signal of LTE-U propagates through a signal path passing through the terminal Port12. For example, a high frequency signal of UHB propagates through the signal path passing through the terminal Port13. For example, a high-frequency signal of HB2 propagates through the signal path passing through the terminal Port14. For example, a high frequency signal of HB1 propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, an LB high-frequency signal propagates through the signal path passing through the terminal Port17.

  For example, LTE-U is a frequency band of 5 GHz band, UHB is a frequency band of 3400 MHz to 3800 MHz, HB2 is a frequency band of 2496 MHz to 2690 MHz, HB1 is a frequency band of 2300 MHz to 2400 MHz, and MB is 1427 MHz. The frequency band is ˜2200 MHz, and LB is the frequency band of 452 MHz to 960 MHz. In addition, said frequency band is an example and this invention is applicable also to another frequency band. The high frequency circuit 2f is, for example, a circuit that branches a signal path connected to the terminal Port11 to each of the terminals Port12 to Port17.

  With this configuration, it is possible to perform carrier aggregation in which six signals having passbands of different frequency bands are transmitted, received, or both at the same time.

  FIG. 17 is a configuration diagram illustrating an example of a high-frequency circuit 2g according to another embodiment.

  As illustrated in FIG. 17, the high-frequency circuit 2 g includes a first circuit 110 b including a second HPF 113. The high-frequency circuit 2g includes a second circuit 120c that is connected in series to the first circuit 110b and includes the BEF 123 and the first BPF 121. At least one of the BEF 123 and the first BPF 121 is composed of an acoustic wave resonator.

  In the high-frequency circuit 2g in FIG. 17, one signal path is divided into two signal paths. That is, the high-frequency circuit 2g in FIG. 17 is a diplexer that divides one signal path into two signal paths.

  For example, a high-frequency signal of HB propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, HB is a frequency band of 2300 MHz to 2690 MHz, and MB is a frequency band of 1427 MHz to 2200 MHz. With this configuration, it is possible to perform carrier aggregation in which two signals having passbands of different frequency bands are transmitted, received, or both at the same time.

  The attenuation amount outside the band in the second HPF 113 is 15 dB or more. The frequency outside the band is, for example, a frequency band of 452 MHz to 960 MHz, which is an LB high frequency signal. With this configuration, the high frequency signal of the LB that has entered from the Port 21 is sufficiently attenuated while reaching the second circuit 120c, so that the distortion characteristics are improved.

  For example, the high-frequency circuit 2g in FIG. 17 is optimally used for applications that do not include LB. For example, 4 × 4 multiple-input and multiple-output using HB high-frequency signal and MB high-frequency signal (so-called 4 × 4 MIMO, technology for simultaneously transmitting / receiving data using four antennas for transmission and reception) It is used optimally.

  FIG. 18 is a configuration diagram illustrating an example of a high-frequency circuit 2h according to another embodiment.

  As shown in FIG. 18, the high-frequency circuit 2h includes a first circuit 110c and a second circuit 120c connected in series to the first circuit 110c. The high frequency circuit 2h includes a third HPF 131 and a third LPF 132. The high-frequency circuit 2h includes terminals Port12, Port13, Port15, and Port16.

  The first circuit 110 c includes a first HPF 111, a second LPF 112, and a second HPF 113. The second circuit 120 c includes a BEF 123 and a first BPF 121. The BEF 123 and the first BPF 121 are composed of acoustic wave resonators. In the present embodiment, for example, both the BEF 123 and the first BPF 121 are constituted by surface acoustic wave resonators.

  For example, an antenna element is connected to the terminal Port11. In addition, high-frequency signals in different frequency bands propagate through signal paths that pass through the terminals Port12, Port13, Port15, and Port16. In the present embodiment, the high frequency circuit 2h is applied to the reception path, and has a function of demultiplexing the high frequency signal input to the terminal Port11 and outputting the demultiplexed signal from the terminals Port12, Port13, Port15, and Port16. Note that the high-frequency circuit 2h may be applied to the transmission path, and may have a function of combining high-frequency signals input to the terminals Port12, Port13, Port15, and Port16 and outputting from the terminal Port11.

  In the high-frequency circuit 2h in FIG. 18, one signal path is divided into four signal paths. That is, the high-frequency circuit 2h in FIG. 18 is a quadplexer that divides one signal path into four signal paths.

  For example, a high-frequency signal of LTE-U propagates through a signal path passing through the terminal Port12. For example, a high frequency signal of UHB propagates through the signal path passing through the terminal Port13. For example, a high-frequency signal of HB propagates through the signal path passing through the terminal Port15. For example, a high frequency signal of MB propagates in a signal path passing through the terminal Port16. For example, LTE-U is a frequency band of 5 GHz band, UHB is a frequency band of 3400 MHz to 3800 MHz, HB is a frequency band of 2300 MHz to 2690 MHz, and MB is a frequency band of 1427 MHz to 2200 MHz. In addition, said frequency band is an example and this invention is applicable also to another frequency band. The high-frequency circuit 2h is, for example, a circuit that branches a signal path connected to the terminal Port11 to each of the terminals Port12, Port13, Port15, and Port16. With this configuration, it is possible to perform carrier aggregation in which four signals having passbands of different frequency bands are transmitted, received, or both at the same time.

  The attenuation of the pass band of the second LPF 112 in the second HPF 113 is 15 dB or more. With this configuration, distortion characteristics are improved.

  For example, the high-frequency circuit 2h in FIG. 18 includes a 4x4 multiple-input and multiple-output (a so-called 4x4 MIMO) using an LTE-U high-frequency signal, a UHB high-frequency signal, an HB high-frequency signal, and an MB high-frequency signal. , A technology for transmitting and receiving data simultaneously using four antennas for transmission and reception).

  Also, for example, in the above embodiment, the BEF included in the first circuit has the circuit configuration shown in FIG. 2A, but is not limited to this, and is realized by another circuit configuration using an acoustic wave resonator. BEF may be used. The BPF included in the second circuit has the circuit configuration shown in FIG. 2B, but is not limited thereto, and may be a BPF realized by another circuit configuration using an acoustic wave resonator. .

  Further, for example, in the first embodiment, three signal paths are combined into one (that is, a triplexer), but not limited thereto, four or more signal paths may be combined into one (that is, a quadruple). Plexers, pentaplexers, hexaplexers or more multiplexers).

  For example, in the second embodiment, one signal path is divided into six signal paths, but the present invention is not limited to this. For example, when the high-frequency circuit 2 does not include the third HPF 131 and the third LPF 132, or when the second circuit 120 includes one BPF, one signal path may be divided into five signal paths. . For example, when the high-frequency circuit 2 does not include the third HPF 131 and the third LPF 132 and the second circuit 120 includes one BPF, one signal path may be divided into four signal paths. Good.

  Moreover, in the modification of Embodiment 1, although the communication apparatus 100 was provided with the high frequency circuit 1a, it is not restricted to this, For example, you may provide the high frequency circuit 1. FIG. That is, the communication device 100 does not have to include the LNA circuit 30, the switch circuit 40, the third circuit 50, and the like.

  In the modification of the second embodiment, the communication device 200 includes the high-frequency circuit 2a. However, the communication device 200 is not limited thereto, and may include the high-frequency circuit 2, for example. That is, the communication apparatus 200 may not include the LNA circuit 160, the switch circuit 170, the third circuit 180, and the like.

  Other forms obtained by subjecting the embodiments to various modifications conceived by those skilled in the art, and forms realized by arbitrarily combining the components and functions of the embodiments without departing from the spirit of the present invention. Are also included in the present invention.

  The present invention is a high-frequency circuit and communication capable of simultaneously transmitting / receiving signals of a plurality of bands of different frequency bands with a simple configuration and capable of increasing the steepness of an attenuation slope located in a transition band in pass characteristics. As a device, it can be widely used in communication devices such as mobile phones.

1, 1a, 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h High-frequency circuit 10, 110, 110a, 110b, 110c First circuit 11, 111 First HPF
12, 114 First LPF
20, 120, 120a, 120b, 120c Second circuit 21, 123 BEF
22, 52-54, 56-58 BPF
30, 160 LNA circuit 31-33, 161-163 LNA
40, 170 Switch circuit 41-43, 70, 171-173 Switch IC
50, 180 Third circuit 51, 55 Multiplexer 80, 190 RF signal processing circuit 90 Multilayer substrate 91 Reference ground layer 92 Reference ground pattern 93 First layer 94, 96, 97 Ground pattern 95 Second layer 100, 200 Communication device 112 Second LPF
113 Second HPF
121 1st BPF
122 2nd BPF
124 HPF
131 Third HPF
132 Third LPF
140 Matching circuit 141, 142 Wiring 150, 211s, 212s, 213p Inductor 181-184 Duplexer 211p, 212p, 213s, 214s, 221s-223s, 221p, 222p
Surface acoustic wave resonator 401, 402 Diplexer

Claims (28)

A first circuit that includes a first high-pass filter and a first low-pass filter and demultiplexes or multiplexes the high-frequency signal;
A second circuit that is connected in series to the first circuit, includes a band elimination filter and a band pass filter, and demultiplexes or multiplexes the high-frequency signal;
At least one of the band elimination filter and the bandpass filter is formed of an acoustic wave resonator,
The pass band of the first high-pass filter is located on a higher frequency side than the pass band of the first low-pass filter,
An attenuation band of the band elimination filter and a pass band of the band pass filter are located between the pass band of the first high pass filter and the pass band of the first low pass filter. The first high-pass filter and the first low-pass filter have a common first common terminal,
The first common terminal and the terminal of the band elimination filter are connected in series,
The band elimination filter and the band pass filter have a common second common terminal,
The attenuation slope in the transition band of the pass characteristic of the band elimination filter includes the attenuation slope in the transition band of the pass characteristic of the first high-pass filter and the attenuation slope in the transition band of the pass characteristic of the first low-pass filter. The high-frequency circuit according to claim 1, wherein at least one is attenuated. The first circuit further includes a second high-pass filter,
The band elimination filter and the band pass filter have a common common terminal,
The common terminal and the terminal of the second high-pass filter are connected;
The pass band of the second high pass filter is located between the pass band of the first high pass filter and the pass band of the first low pass filter;
The high frequency circuit according to claim 1, wherein a pass band of the second high pass filter, a pass band of the band pass filter, and an attenuation band of the band elimination filter overlap. The first circuit further includes a second low-pass filter;
The second high-pass filter and the first low-pass filter are connected to the second low-pass filter;
The high-frequency circuit further includes a third high-pass filter and a third low-pass filter,
The third high pass filter and the third low pass filter are connected to the first high pass filter,
The high-frequency circuit according to claim 3, wherein the high-frequency circuit is a pentaplexer. The first circuit further includes a second low-pass filter;
The second high-pass filter and the first low-pass filter are connected to the second low-pass filter;
The high-frequency circuit further includes a third high-pass filter and a third low-pass filter,
The third high pass filter and the third low pass filter are connected to the first high pass filter,
The second circuit further includes a band pass filter or a high pass filter,
The high frequency circuit according to claim 3, wherein the high frequency circuit is a hexaplexer. A first circuit that includes a second high-pass filter and a first low-pass filter and demultiplexes or multiplexes the high-frequency signal;
A second circuit that is connected in series to the first circuit, includes a band elimination filter and a band pass filter, and demultiplexes or multiplexes the high-frequency signal;
At least one of the band elimination filter and the bandpass filter is formed of an acoustic wave resonator,
The pass band of the second high pass filter is located on a higher frequency side than the pass band of the first low pass filter,
The attenuation band of the band elimination filter and the pass band of the band pass filter are located higher than the pass band of the first low pass filter, and the pass band of the second high pass filter Overlapping high-frequency circuit. The high-frequency circuit according to claim 6, wherein the high-frequency circuit is a triplexer. The second circuit further includes a high-pass filter,
The high-frequency circuit according to claim 6, wherein the high-frequency circuit is a quadplexer. The second circuit further includes a bandpass filter;
The high-frequency circuit according to claim 6, wherein the high-frequency circuit is a quadplexer. The amount of attenuation in the band corresponding to the pass band of the first low-pass filter in the second high-pass filter is 15 dB or more compared to the case where the first low-pass filter is not provided.
The second high pass filter includes an inductor and a capacitor,
The high-frequency circuit according to claim 3, wherein the first low-pass filter includes an inductor and a capacitor. A first circuit that includes a second high-pass filter and demultiplexes or multiplexes the high-frequency signal;
A second circuit that is connected in series to the first circuit, includes a band elimination filter and a band pass filter, and demultiplexes or multiplexes the high-frequency signal;
At least one of the band elimination filter and the bandpass filter is formed of an acoustic wave resonator,
The attenuation band of the band elimination filter and the pass band of the band pass filter overlap with the pass band of the second high pass filter,
The band elimination filter is a hybrid filter composed of at least one elastic wave resonator and at least one inductor,
The high-frequency circuit is a multiplexer that simultaneously transmits, receives, or both a plurality of signals. The first circuit further includes a first high pass filter and a second low pass filter;
The second high pass filter is connected to the second low pass filter;
The high-frequency circuit further includes a third high-pass filter and a third low-pass filter,
The high-frequency circuit according to claim 11, wherein the third high-pass filter and the third low-pass filter are connected to the first high-pass filter. The high-frequency circuit according to claim 3, further comprising a matching circuit connected between the second high-pass filter and the second circuit. The high-frequency circuit according to claim 13, wherein the matching circuit includes at least one of an inductor and a capacitor. The band-pass filter includes a first band-pass filter and a second band-pass filter having different pass bands,
The matching circuit is connected to the first bandpass filter and the second bandpass filter;
Of the pass band of the first band pass filter and the pass band of the second band pass filter, the pass band of the first band pass filter is closer to the desired pass band of the band elimination filter. Located in
The high-frequency circuit according to claim 13 or 14, wherein a wiring that connects the matching circuit and the first bandpass filter is shorter than a wiring that connects the matching circuit and the second bandpass filter. The high-frequency circuit according to claim 1, wherein the band-pass filter includes a first band-pass filter and a second band-pass filter having different pass bands. The high-frequency circuit according to any one of claims 1 to 16, wherein the high-pass filter and the low-pass filter included in the high-frequency filter are LC resonance circuits. The high-frequency circuit according to claim 1, wherein an inductor is connected in parallel to the bandpass filter. The high frequency circuit further includes a low noise amplifier circuit,
The high-frequency circuit according to claim 1, wherein the first circuit and the low-noise amplifier circuit are formed on the same chip. The high-frequency circuit further includes a switch circuit,
The high-frequency circuit according to claim 1, wherein the first circuit and the switch circuit are formed on the same chip. The high-frequency circuit includes a laminated substrate configured by laminating a plurality of layers,
The high-pass filter and low-pass filter included in the high-frequency filter are each an LC resonance circuit,
The band elimination filter and the band pass filter are ladder type surface acoustic wave filters,
The multilayer substrate has a reference ground layer, a first layer, and a second layer, which are the lowest layers of the multilayer substrate,
The reference ground layer is provided with a reference ground pattern serving as a reference potential of the multilayer substrate,
The first layer is provided with a ground pattern of the first circuit electrically connected to the reference ground pattern,
The second layer is provided with a ground pattern of the second circuit electrically connected to the reference ground pattern,
The high-frequency circuit according to claim 1, wherein the first layer is located closer to the reference ground layer than the second layer. The high-frequency circuit is
Including a laminated substrate configured by laminating a plurality of layers;
Further, a third branching circuit that is an elastic wave filter is provided,
The ground pattern of the second circuit and the ground pattern of the third branching circuit are provided separately from each other in one of the plurality of layers. The high-frequency circuit described. The high-frequency circuit according to any one of claims 1 to 22, wherein the band elimination filter is a hybrid filter including at least one elastic wave resonator and at least one inductor. The high-frequency circuit according to any one of claims 1 to 23, wherein the high-frequency circuit is a multiplexer that simultaneously transmits, receives, or both a plurality of signals. The high-frequency circuit according to any one of claims 1 to 24, wherein a part of a pass band of the band-pass filter overlaps a part of an attenuation band of the band elimination filter. The high-frequency circuit according to claim 1, wherein a part of a desired pass band of the band elimination filter is lower than a pass band of the band pass filter. The high-frequency circuit according to any one of claims 1 to 26, wherein the band elimination filter includes a low-pass filter type circuit and a high-pass filter type circuit connected in series to the low-pass filter type circuit. An RF signal processing circuit for processing a high-frequency signal transmitted and received by the antenna element;
A high-frequency circuit according to any one of claims 1 to 27, wherein the high-frequency signal is transmitted between the antenna element and the RF signal processing circuit.

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