High-frequency modules and communication devices

Abstract

The present invention provides a high-frequency module that suppresses unwanted wave leakage between power amplifiers and enables miniaturization. [Solution] The high-frequency module 1 comprises a first drive stage amplifier 71, a second drive stage amplifier 81, a final stage amplifier 72, a first matching circuit 73, and a second matching circuit 83. The first drive stage amplifier 71 is connected to a first input 76. The second drive stage amplifier 81 is connected to a second input 77. The final stage amplifier 72 is connected to output 78 and 79. The first matching circuit 73 is connected between the first drive stage amplifier 71 and the final stage amplifier 72 and is a filter-type matching circuit having a first passband including a first communication band and a first attenuation band including a second communication band. The second matching circuit 83 is connected between the second drive stage amplifier 81 and the final stage amplifier 72 and is a filter-type matching circuit having a second passband including a second communication band and a second attenuation band including a first communication band.

Description

Technical Field

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[0001] The present invention generally relates to a high-frequency module and a communication device, and more particularly to a high-frequency module including a plurality of power amplifiers and a communication device including the high-frequency module.

Background Art

[0002] The high-frequency module described in Patent Document 1 includes a first power amplifier that amplifies a transmission signal in a first frequency band and a second power amplifier that amplifies a transmission signal in a second frequency band. The first power amplifier has a first drive-stage amplifier section and a first final-stage amplifier section. The second power amplifier has a second drive-stage amplifier section and a second final-stage amplifier section.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The high-frequency module described in Patent Document 1 includes a drive-stage amplifier section and a final-stage amplifier section for each frequency band. In particular, the final-stage amplifier section that generates a high-output amplified signal has a large size, resulting in a problem that the high-frequency module becomes large-sized. In addition, when a plurality of power amplifiers are provided, unnecessary waves may leak between the power amplifiers.

[0005] In view of the above problems, an object of the present invention is to provide a high-frequency module and a communication device capable of suppressing leakage of unnecessary waves between power amplifiers and miniaturization.

Means for Solving the Problems

[0006] A high-frequency module according to one aspect of the present invention comprises a first input section, a second input section, a first output section, a first drive stage amplifier section, a second drive stage amplifier section, a final stage amplifier section, a first matching circuit, and a second matching circuit. The first input section receives a first transmission signal in a first communication band. The second input section receives a second transmission signal in a second communication band different from the first communication band. The first drive stage amplifier section is connected downstream of the first input section. The second drive stage amplifier section is connected downstream of the second input section. The final stage amplifier section is connected upstream of the first output section. The first matching circuit is connected between the first drive stage amplifier section and the final stage amplifier section and is a filter-type matching circuit having a first passband including the first communication band and a first attenuation band including the second communication band. The second matching circuit is connected between the second drive stage amplifier and the final stage amplifier and is a filter-type matching circuit having a second passband including the second communication band and a second attenuation band including the first communication band.

[0007] A communication device according to one aspect of the present invention comprises the high-frequency module and a signal processing circuit. The signal processing circuit is connected to the high-frequency module and processes high-frequency signals. [Effects of the Invention]

[0008] The high-frequency module and communication device according to the present invention have the advantage of suppressing the leakage of unwanted waves between power amplifiers and enabling miniaturization. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a block diagram of a high-frequency module and communication device according to an embodiment. [Figure 2] Figure 2 is a block diagram of the multiband coupler of the same high-frequency module. [Figure 3] Figure 3 is a block diagram of a high-frequency module and communication device according to a modified embodiment. [Modes for carrying out the invention]

[0010] (Embodiment) The high-frequency module 1 and communication device 200 according to this embodiment will be described in detail with reference to the drawings.

[0011] (1) Overview As shown in Figure 1, the high-frequency module 1 according to the embodiment includes a first input section 76, a second input section 77, first output sections 78 and 79, a first drive stage amplifier section 71, a second drive stage amplifier section 81, a final stage amplifier section 72, a first matching circuit 73, and a second matching circuit 83. The first input section 76 receives a first transmission signal in a first communication band. The second input section 77 receives a second transmission signal in a second communication band different from the first communication band. The first drive stage amplifier section 71 is connected downstream of the first input section 76. The second drive stage amplifier section 81 is connected downstream of the second input section 77. The final stage amplifier section 72 is connected upstream of the first output sections 78 and 79. The first matching circuit 73 is connected between the first drive stage amplifier section 71 and the final stage amplifier section 72 and is a filter-type matching circuit having a first passband including the first communication band and a first attenuation band including the second communication band. The second matching circuit 83 is connected between the second drive stage amplifier 81 and the final stage amplifier 72, and is a filter-type matching circuit having a second passband including the second communication band and a second attenuation band including the first communication band.

[0012] With this configuration, the final stage amplifier for the first communication band and the final stage amplifier for the second communication band, which occupy a large area, are combined into a single final stage amplifier 72, thus enabling miniaturization of the high-frequency module 1.

[0013] Furthermore, a filter-type first matching circuit 73 is connected between the first drive stage amplifier 71 and the final stage amplifier 72, and a filter-type second matching circuit 83 is connected between the second drive stage amplifier 81 and the final stage amplifier 72. This prevents unwanted signal components in the same frequency band as the second communication band from leaking to the second drive stage amplifier 81 side as unwanted waves, and prevents unwanted signal components in the same frequency band as the first communication band from leaking to the first drive stage amplifier 71 side as unwanted waves. As a result, leakage of unwanted waves between power amplifiers 7 and 8 can be suppressed.

[0014] (2) Configuration of the communication device As shown in Figure 1, the communication device 200 is a communication device equipped with a high-frequency module 1. The communication device 200 is, for example, a mobile terminal (e.g., a smartphone), but is not limited to a mobile terminal; it may also be, for example, a wearable terminal (e.g., a smartwatch). The high-frequency module 1 is, for example, a module compatible with 4G (fourth-generation mobile communication) standards and 5G (fifth-generation mobile communication) standards. The 4G standard is, for example, 3GPP (registered trademark, Third Generation Partnership Project) or the LTE standard (registered trademark, Long Term Evolution). The 5G standard is, for example, 5G NR (New Radio).

[0015] In addition to the high-frequency module 1, the communication device 200 further includes a signal processing circuit 2 and antennas 3 and 4.

[0016] The high-frequency module 1 is configured to amplify the transmission signal (high-frequency signal) output from the signal processing circuit 2 and transmit it from antenna 3 or 4. The high-frequency module 1 is also configured to amplify the received signal (high-frequency signal) received by antenna 3 or 4 and output it to the signal processing circuit 2. The high-frequency module 1 is controlled, for example, by the signal processing circuit 2.

[0017] The signal processing circuit 2 is connected to the high-frequency module 1 and processes high-frequency signals. More specifically, the signal processing circuit 2 is configured to process the transmission signal output to the high-frequency module 1. Also, the signal processing circuit 2 is configured to process the reception signal output from the high-frequency module 1. The signal processing circuit 2 includes an RF (Radio Frequency) signal processing circuit 121 and a baseband signal processing circuit 122.

[0018] The RF signal processing circuit 121 is, for example, an RFIC (Radio Frequency Integrated Circuit) and performs signal processing on high-frequency signals (transmission signals and reception signals). The RF signal processing circuit 121 performs signal processing such as up-converting the transmission signal output from the baseband signal processing circuit 122 and outputs it to the high-frequency module 1. Also, the RF signal processing circuit 121 performs signal processing such as down-converting the reception signal output from the high-frequency module 1 and outputs it to the baseband signal processing circuit 122.

[0019] The baseband signal processing circuit 122 is, for example, a BBIC (Baseband Integrated Circuit). The baseband signal processing circuit 122 generates a transmission signal from baseband signals input from the outside (for example, voice signals and image signals), and outputs the generated transmission signal to the RF signal processing circuit 121. Also, the baseband signal processing circuit 122 outputs the reception signal output from the RF signal processing circuit 121 to the outside. This output signal (reception signal) can be used, for example, for image display as an image signal or for a call as a voice signal.

[0020] (3) Configuration of the high-frequency module 1 The high-frequency module 1 transmits the first transmission signal of the first communication band and the second transmission signal of the second communication band, and also receives the first reception signal of the first communication band and the second reception signal of the second communication band. The first communication band and the second communication band are different communication bands from each other. More specifically, the second communication band is a communication band in a higher frequency band than the first communication band. The first communication band is, for example, n77. The second communication band is, for example, n79.

[0021] As shown in FIG. 1, the high-frequency module 1 includes, for example, a plurality of external terminals 5a to 5j, an antenna switch 6, a first power amplifier 7, a second power amplifier 8, an output matching circuit 9, a variable low-pass filter 10, a multi-band coupler 11, high-pass filters 12 and 13, diplexers 14 and 15, matching circuits 16 to 19, low-noise amplifiers 20 to 23, and a controller 24. Note that the controller 24 may be separated according to the functions of a transmission controller and a reception controller.

[0022] (3.1) External Terminals External terminal 5a is the first antenna terminal connected to the first antenna 3. External terminal 5b is the second antenna terminal connected to the second antenna 4. External terminal 5c is connected to the output section of the signal processing circuit 2 and is an input terminal to which the first transmission signal of the first communication band output from the output section of the signal processing circuit 2 is input. External terminal 5d is connected to the output section of the signal processing circuit 2 and is an input terminal to which the second transmission signal of the second communication band output from the output section of the signal processing circuit 2 is input. External terminals 5e and 5g are connected to the input sections of the signal processing circuit 2, respectively, and are output terminals that output the first received signal of the first communication band processed by the high-frequency module 1 to the input section of the signal processing circuit 2. External terminals 5f and 5h are connected to the input sections of the signal processing circuit 2, respectively, and are output terminals that output the second received signal of the second communication band processed by the high-frequency module 1 to the input section of the signal processing circuit 2. External terminal 5i is connected to the signal output section of the signal processing circuit 2 and is an input terminal for receiving control signals from the signal processing circuit 2 to control the controller 24. External terminal 5j is an external terminal for outputting the detection signal of the multiband coupler 11 to the outside.

[0023] (3.2) Antenna switch Antenna switch 6 is a switch for selecting which antenna to use from among antennas 3 and 4. More specifically, when transmitting, antenna switch 6 selects one or more antennas (for example, one) from among antennas 3 and 4 as the connection destination for transmission path TL1, and connects the selected antenna to transmission path TL1. When receiving, antenna switch 6 selects one or more antennas from among antennas 3 and 4, selects the connection destination for the selected antenna from two receiving paths RL1 and RL2, and connects the selected antenna to the selected receiving path. Antenna switch 6 is controlled by a control signal from controller 24. Antenna switch 6 is, for example, a switch IC (Integrated Circuit).

[0024] The antenna switch 6 has terminals 6a to 6e. Terminal 6a is connected to the transmission path TL1. The transmission path TL1 connects terminal 6a to the output section of the variable low-pass filter 10. Terminal 6b is connected to the external terminal 5a via the high-pass filter 12. Terminal 6c is connected to the external terminal 5b via the high-pass filter 13. In other words, the antenna switch 6 is connected to the downstream stage of the variable low-pass filter 10 and to the external terminals 5a and 5b. Terminal 6d is connected to the first reception path RL1. The first reception path RL1 connects terminal 6d to the input section of the diplexer 14. Terminal 6e is connected to the second reception path RL2. The second reception path RL2 connects terminal 6e to the input section of the diplexer 15. During transmission, terminal 6a is selectively connected to one of the two terminals 6b and 6c. During reception, terminals 6b and 6c each selectively connect to a different terminal from the two terminals 6d and 6e.

[0025] The antenna switch 6 is connected downstream of the variable low-pass filter 10. Note that "connected downstream of the variable low-pass filter 10" includes cases where the antenna switch 6 is indirectly connected to the variable low-pass filter 10 via an electronic component (e.g., a multiband coupler 11), and cases where it is directly connected to the variable low-pass filter 10 without an electronic component. In this embodiment, the antenna switch 6 is connected to the variable low-pass filter 10 via a multiband coupler 11.

[0026] The antenna switch 6 is equipped with the variable capacitor C4 of the output matching circuit 9 (described later) and the variable capacitor C5 of the variable low-pass filter 10 (described later). In other words, the variable capacitors C4 and C5 are integrated with the antenna switch 6.

[0027] (3.3) First power amplifier and second power amplifier The first power amplifier 7 is an amplification unit that amplifies the first transmission signal of the first communication band. The first power amplifier 7 is connected between the external terminal 5c and the output matching circuit 9. The first power amplifier 7 is a multi-stage (two in the example in Figure 1) amplification unit. The first power amplifier 7 comprises a first drive stage amplification unit 71, a final stage amplification unit 72, a first matching circuit 73, a first input unit 76, a second input unit 77, and output units 78, 79 (first output unit).

[0028] The first input section 76 is connected to the external terminal 5c. The second input section 77 is connected to the external terminal 5d. The output section 78 is connected to the first end 91a of the balanced coil 91 of the transformer 90, which will be described later. The output section 79 is connected to the second end 91b of the balanced coil 91.

[0029] The first drive stage amplifier 71 is connected to the stage after the first input 76. The first drive stage amplifier 71 has an input section and an output section. The input section of the first drive stage amplifier 71 is connected to the first input 76. The output section of the first drive stage amplifier 71 is connected via the first matching circuit 73 to the input section of the final stage amplifier 72 (i.e., the input section of the first amplifier 74 and the input section of the second amplifier 75 described later). The first drive stage amplifier 71 amplifies the signal input to the input section (first transmission signal) at a predetermined amplification factor and outputs the amplified signal from the output section.

[0030] The final stage amplifier 72 is connected to the stage before the output sections 78 and 79. The final stage amplifier 72 further amplifies the signal amplified by the first drive stage amplifier 71. The final stage amplifier 72 comprises a first amplifier 74 and a second amplifier 75. The first amplifier 74 has an input section and an output section. The second amplifier has an input section and an output section. The input sections of the first amplifier 74 and the second amplifier 75 are connected to each other and are connected to the output section of the first drive stage amplifier 71 via the first matching circuit 73. The output section of the first amplifier 74 is connected to the output section 78. That is, the output section of the first amplifier 74 is connected to the first end 91a of the balanced coil 91 via the output section 78. The output section of the second amplifier 75 is connected to the output section 79. That is, the output section of the second amplifier 75 is connected to the second end 91b of the balanced coil 91 via the output section 79. The first amplifier 74 amplifies the signal input to its input terminal at a predetermined amplification factor and outputs the amplified signal from its output terminal. The second amplifier 75 amplifies the signal input to its input terminal at a predetermined amplification factor and outputs the amplified signal from its output terminal.

[0031] The first matching circuit 73 is, for example, a low-pass filter type (i.e., filter type) matching circuit. The first matching circuit 73 is connected between the first drive stage amplifier 71 and the final stage amplifier 72, and provides impedance matching between the first drive stage amplifier 71 and the final stage amplifier 72.

[0032] Furthermore, the first matching circuit 73 is configured to function as, for example, a low-pass filter. More specifically, the first matching circuit 73 functions as a filter having a first passband including a first communication band (e.g., n77) and a first attenuation band including a second communication band (e.g., n79). The first matching circuit 73 has an input section and an output section. The input section of the first matching circuit 73 is connected to the output section of the first drive stage amplifier 71. The output section of the first matching circuit 73 is connected to the input section of the final stage amplifier 72 (the input sections of the first amplifier 74 and the second amplifier 75, respectively). The first matching circuit 73 passes signals in the same frequency band as the first communication band and blocks signals in the same frequency band as the second communication band from the signals input to the input section (i.e., the output signals of the first drive stage amplifier 71), and blocks signals in the same frequency band as the second communication band. The first matching circuit 73 then outputs the passed signals from its output section. Since the first communication band is, for example, n77 (i.e., a relatively low frequency band) and the second communication band is, for example, n79 (a relatively high frequency band), the first matching circuit 73 is, for example, a low-pass filter type matching circuit.

[0033] The second power amplifier 8 is an amplification unit that amplifies the second transmission signal of the second communication band. The second power amplifier 8 is connected between the external terminal 5d and the output matching circuit 9. The second power amplifier 8 is a multi-stage (two stages in the example in Figure 1) amplification unit. The second power amplifier 8 comprises a second drive stage amplification unit 81, a final stage amplification unit 72, and a second matching circuit 83. The final stage amplification unit 72 is shared with the final stage amplification unit 72 of the first power amplifier 7. That is, the final stage amplification unit 72 is shared between the first power amplifier 7 and the second power amplifier 8.

[0034] The second drive stage amplifier 81 is connected downstream of the second input 77. The second drive stage amplifier 81 has an input section and an output section. The input section of the second drive stage amplifier 81 is connected to the external terminal 5d. The output section of the second drive stage amplifier 81 is connected to the input section of the final stage amplifier 72 (i.e., the input sections of the first amplifier 74 and the second amplifier 75) via the second matching circuit 83. The second drive stage amplifier 81 amplifies the signal input to the input section (second transmission signal) at a predetermined amplification factor and outputs the amplified signal from the output section.

[0035] As described above, the final stage amplifier 72 is connected to the stage before the output sections 78 and 79. The final stage amplifier 72 further amplifies the signal amplified by the second drive stage amplifier 81. As described above, the final stage amplifier 72 comprises a first amplifier 74 and a second amplifier 75. As described above, the first amplifier 74 has an input section and an output section. As described above, the second amplifier has an input section and an output section. The input sections of the first amplifier 74 and the second amplifier 75 are connected to each other as described above, and are further connected to the output section of the second drive stage amplifier 81 via the second matching circuit 83. As described above, the output sections of the first amplifier 74 and the second amplifier 75 are connected to each other via the balanced coil 91. That is, the output section of the first amplifier 74 is connected to the first end 91a of the balanced coil 91, and the output section of the second amplifier 75 is connected to the second end 91b of the balanced coil 91.

[0036] The second matching circuit 83 is, for example, a high-pass filter type (i.e., filter type) matching circuit. The second matching circuit 83 is connected between the second drive stage amplifier 81 and the final stage amplifier 72, and provides impedance matching between the second drive stage amplifier 81 and the final stage amplifier 72.

[0037] Furthermore, the second matching circuit 83 is configured to function, for example, as a high-pass filter. More specifically, the second matching circuit 83 functions as a filter having a second passband including a second communication band (e.g., n79) and a second attenuation band including a first communication band (e.g., n77). The second matching circuit 83 has an input section and an output section. The input section of the second matching circuit 83 is connected to the output section of the second drive stage amplifier 81. The output section of the second matching circuit 83 is connected to the input section of the final stage amplifier 72 (the input sections of the first amplifier 74 and the second amplifier 75, respectively). The second matching circuit 83 allows signals in the same frequency band as the second communication band to pass through and blocks signals in the same frequency band as the first communication band from the signals input to the input section (i.e., the output signals of the second drive stage amplifier 81), and blocks signals in the same frequency band as the first communication band. The second matching circuit 83 then outputs the passed signals from its output section. Since the first communication band is, for example, n77 (i.e., a relatively low frequency band) and the second communication band is, for example, n79 (a relatively high frequency band), the second matching circuit 83 is, for example, a high-pass filter type matching circuit.

[0038] The first power amplifier 7 and the second power amplifier 8 are integrally formed by a semiconductor chip 30. Specifically, the semiconductor chip 30 includes a first input section 76, a second input section 77, output sections 78 and 79, a first drive stage amplification section 71, a second drive stage amplification section 81, matching circuits 73 and 83, and a final stage amplification section 72.

[0039] In the first power amplifier 7 and second power amplifier 8 configured in this way, the final stage amplification section 72 of the first power amplifier 7 and the final stage amplification section 72 of the second power amplifier 8 are shared by a single final stage amplification section 72, so the entire first power amplifier 7 and second power amplifier 8 (i.e., the semiconductor chip 30) can be miniaturized. In other words, the high-frequency module 1 can be miniaturized.

[0040] Furthermore, since the first power amplifier 7 is equipped with a low-pass filter type first matching circuit 73, it can suppress the leakage of signal components in the same frequency band as the second communication band from the output signal of the first drive stage amplifier 71 to the second drive stage amplifier 81 side as unwanted waves. Also, since the second power amplifier 8 is equipped with a high-pass filter type second matching circuit 83, it can suppress the leakage of signal components in the same frequency band as the first communication band from the output signal of the second drive stage amplifier 81 to the first drive stage amplifier 71 side as unwanted waves.

[0041] (3.4) Output matching circuit The output matching circuit 9 is connected between the final stage amplifier 72 and the variable low-pass filter 10 to match the impedance between the final stage amplifier 72 and the variable low-pass filter 10. The output matching circuit 9 includes a transformer 90, capacitors C1 to C3, and a variable capacitor C4.

[0042] The transformer 90 combines the first balanced amplification signal, which is the output signal of the first amplification unit 74, and the second balanced amplification signal, which is the output signal of the second amplification unit 75, to convert them into an unbalanced amplification signal, and outputs the converted unbalanced amplification signal to the next stage. The transformer 90 includes a balanced coil 91, an unbalanced coil 92, and a capacitor C1.

[0043] The balanced coil 91 is used as the primary coil of the transformer 90. The balanced coil 91 has a first end 91a, a second end 91b, and a center tap 91c. The first end 91a is one end of the balanced coil 91 and is the input terminal to which the first amplified balanced signal is input. The first end 91a is connected to the output section of the first amplifier 74. The second end 91b is the other end of the balanced coil 91 and is the input terminal to which the second amplified balanced signal is input. The second end 91b is connected to the output section of the second amplifier 75. The center tap 91c is a point in the balanced coil 91 that is electrically grounded between the first end 91a and the second end 91b. The center tap 91c is connected to ground via a capacitor C1, and power is supplied to the first amplifier 74 and the second amplifier 75 via this center tap 91c. In this case, the capacitor C1 functions as a bypass capacitor to reduce unwanted noise in the power supply path.

[0044] The unbalanced coil 92 is used as the secondary coil of the transformer 90. The unbalanced coil 92 is electromagnetically coupled to the balanced coil 91. The unbalanced coil 92 has a third end 92a and a fourth end 92b. The third end 92a is one end of the unbalanced coil 92 and is the output terminal to which the amplified unbalanced signal is output. The third end 92a is connected to the input of the variable low-pass filter 10 via a capacitor C2. The fourth end 92b is the other end of the unbalanced coil 92 and is connected to ground.

[0045] Capacitors C2, C3, and variable capacitor C4 remove high-frequency noise components contained in the output signal of transformer 90 (the amplified unbalanced signal described above). Capacitor C2 is connected between the third terminal 92a of the unbalanced coil 92 and the input of the variable low-pass filter 10. Capacitors C3 and variable capacitor C4 are connected between the branch point N1 between the third terminal 92a and capacitor C2 and ground, and are connected in series with each other. Variable capacitor C4 is, for example, a digital variable capacitor. Variable capacitor C4 is located inside the antenna switch 6 and is configured integrally with the antenna switch 6.

[0046] The variable capacitor C4 is a variable element for changing the output matching characteristics of the output matching circuit 9 according to the communication band (first communication band or second communication band) of the transmitted signal (output signals of output units 78 and 79). More specifically, if the communication band of the transmitted signal is the first communication band, the first communication band (e.g., n77) is a relatively low-frequency band, so the variable capacitor C4 is adjusted to have a larger capacitance, for example. If the communication band of the transmitted signal is the second communication band, the second communication band (e.g., n79) is a relatively high-frequency band, so the variable capacitor C4 is adjusted to have a smaller capacitance. The variable capacitor C4 is controlled by a control signal from the controller 24.

[0047] (3.5) Variable Low-Pass Filter The variable low-pass filter 10 is a filter for attenuating unwanted high-frequency waves in the transmitted signal (output signals of output sections 78 and 79). The variable low-pass filter 10 is a low-pass filter with a changeable passband. More specifically, the variable low-pass filter 10 has a changeable passband through which the signal passes, and an attenuation band that is higher in frequency than the passband and attenuates (i.e., blocks) the signal. The passband of the variable low-pass filter 10 is changed to match the communication band of the transmitted signal. "The passband of the variable low-pass filter 10 matches the communication band of the transmitted signal" means that the upper limit of the passband (cutoff frequency) of the variable low-pass filter 10 is made to match or approach (or even approach) the upper limit of the passband. That is, if the communication band of the transmitted signal is the first communication band, the variable low-pass filter 10 is changed to match the first communication band, and if the communication band of the transmitted signal is the second communication band, the variable low-pass filter 10 is changed to match the second communication band. The variable low-pass filter 10 is controlled by a control signal from the controller 24.

[0048] The variable low-pass filter 10 has an input section and an output section. The input section of the variable low-pass filter 10 is connected to the output section of the output matching circuit 9 (i.e., after the capacitor C2). The output section of the variable low-pass filter 10 is connected to terminal 6a of the antenna switch 6 via the transmission path TL1. The variable low-pass filter 10 allows signal components of the signal (transmission signal) input to the input section that are in the same frequency band as the communication band of the transmission signal to pass through, and blocks signal components in a frequency band higher than the communication band of the transmission signal. More specifically, when transmitting the first transmission signal in the first communication band, the passband of the variable low-pass filter 10 is changed to match the first communication band, so the variable low-pass filter 10 allows signal components in the same frequency band as the first communication band to pass through, and blocks signal components in a frequency band higher than the first communication band. Furthermore, when transmitting the second transmission signal in the second communication band, the passband of the variable low-pass filter 10 is changed to match the second communication band. As a result, the variable low-pass filter 10 allows signal components in the same frequency band as the second communication band to pass through, while blocking signal components in a higher frequency band than the second communication band. The transmission signal that has passed through the variable low-pass filter 10 is then output to the next stage from the output section.

[0049] The variable low-pass filter 10 is connected to the output sections 78 and 79. Note that "connected to the output sections 78 and 79" includes cases where the filter is indirectly connected to the output sections 78 and 79 via electronic components (e.g., the output matching circuit 9), and cases where it is directly connected to the output sections 78 and 79 without the use of electronic components. In this embodiment, the variable low-pass filter 10 is connected to the output sections 78 and 79 via the output matching circuit 9.

[0050] The variable low-pass filter 10 has a variable capacitor C5 for changing the passband. The passband of the variable low-pass filter 10 is changed to match the communication band of the transmitted signal by changing the capacitance of the variable capacitor C5. The variable capacitor C5 is located inside the antenna switch 6 and is integrated with the antenna switch 6.

[0051] (3.6) Multiband coupler The multiband coupler 11 is a device that extracts a portion of the transmission signal (high-frequency signal) passing through the main line 42, which is a section of the transmission path TL1 (see Figure 1) within the high-frequency module 1, as a detected signal from a sub-line 43 that is electromagnetically coupled to the main line 42 (see Figure 2). The multiband coupler 11 is equipped with a sub-line 43 whose length can be changed by magnetic field coupling with the main line 42, and detects the transmission signal of the communication band corresponding to the length of the sub-line 43. The multiband coupler 11 detects the transmission signal passing through the main line 42 by changing the length of the sub-line 43 to a length corresponding to the communication band of the transmission signal (first communication band or second communication band). More specifically, when transmitting a first transmission signal in the first communication band, the multiband coupler 11 detects the first transmission signal flowing through the main line 42 by changing the length of the sub-line 43 to a length corresponding to the first communication band (the sum of the lengths of the first sub-line 50 and the second sub-line 51). When transmitting a second transmission signal in the second communication band, it detects the second transmission signal passing through the main line 42 by changing the length of the sub-line 43 to a length corresponding to the second communication band (the length of the first sub-line 50). The multiband coupler 11 is controlled by a control signal from the controller 24.

[0052] More specifically, as shown in Figure 2, the multiband coupler 11 comprises a main line 42, a secondary line 43, a termination circuit 44, a first phase shift circuit 45, a first changeover switch 46, a second changeover switch 47, and a termination switch 48. Furthermore, as described above, the multiband coupler 11 includes a first connection terminal 181, a second connection terminal 182, and a third connection terminal 183.

[0053] The first connection terminal 181 is connected to the output section of the variable low-pass filter 10 (see Figure 1) and is the input terminal for the output signal of the variable low-pass filter 10 (the transmitted signal to be detected). The second connection terminal 182 is connected to terminal 6a of the antenna switch 6 (see Figure 1) and is the output terminal for the transmitted signal after detection to terminal 6a. The third connection terminal 183 is the output terminal for the detected signal acquired by detection and is connected to the external terminal 5j (see Figure 1).

[0054] The main line 42 is the line through which the transmission signal (high-frequency signal) to be detected passes, and constitutes part of the transmission path TL1. The first end 42a of the main line 42 is connected to the first connection terminal 181. The second end 42b of the main line 42 is connected to the second connection terminal 182.

[0055] The auxiliary line 43 is electromagnetically coupled to the main line 42 and is a line that extracts a portion of the high-frequency signal (transmission signal) flowing through the main line 42 as a detected signal. The auxiliary line 43 has a first auxiliary line 50 and a second auxiliary line 51. The first end 50a of the first auxiliary line 50 is connected to the first changeover switch 46. The second end 50b of the first auxiliary line 50 is connected to the third connection terminal 183. The first end 51a of the second auxiliary line 51 is connected to the termination switch 48. The second end 51b of the second auxiliary line 51 is connected to the second changeover switch 47.

[0056] The termination circuit 44 is a circuit for terminating either the first auxiliary line 50 or the second auxiliary line 51.

[0057] The first phase shift circuit 45 is connected between the first auxiliary line 50 and the second auxiliary line 51, which are used as auxiliary lines 43 in the second mode described later, and is a circuit for adjusting the phase of the auxiliary line 43. By adjusting the phase of the auxiliary line 43 in the second mode, the first phase shift circuit 45 suppresses the leakage of high-frequency signals from the main line 42 to the auxiliary line 43. The first phase shift circuit 45 is provided between the first end 50a of the first auxiliary line 50 and the second end 51b of the second auxiliary line 51.

[0058] The first changeover switch 46 switches the connection destination of the first end 50a of the first auxiliary line 50 to either the first end 45a of the first phase shift circuit 45 or the termination switch 48. The second changeover switch 47 is located between the first phase shift circuit 45 and the second auxiliary line 51 and switches the connection and disconnection between the second end 45b of the first phase shift circuit 45 and the second end 51b of the second auxiliary line 51. The termination switch 48 switches the connection destination of the termination circuit 44 to either the first changeover switch 46 or the first end 51a of the second auxiliary line 51.

[0059] The first changeover switch 46, the second changeover switch 47, and the termination switch 48 are controlled by control signals from the controller 24.

[0060] The multiband coupler 11 has a first mode and a second mode.

[0061] The first mode is a mode in which the transmission signal for the first communication band is detected from the high-frequency signals flowing through the main line 42. In the first mode, the first changeover switch 46 switches the connection destination of the first end 50a of the first sub-line 50 to the first phase shift circuit 45, the second changeover switch 47 connects the first phase shift circuit 45 to the second end 51b of the second sub-line 51, and the termination switch 48 switches the connection destination of the termination circuit 44 to the first end 51a of the second sub-line 51. As a result, the sub-line 43 in the first mode is composed of a series circuit of the first sub-line 50, the first phase shift circuit 45, and the second sub-line 51. In the first mode, by using the above series circuit as the sub-line 43, the transmission signal for the first communication band is detected from the high-frequency signals flowing through the main line 42.

[0062] The second mode is a mode in which the transmission signal for the second communication band is detected from the high-frequency signals flowing through the main line 42. In the second mode, the first changeover switch 46 switches the connection destination of the first end 50a of the first sub-line 50 to the termination switch 48, and the termination switch 48 switches the connection destination of the termination circuit 44 to the first end 50a of the first sub-line 50. As a result, the sub-line 43 in the second mode is composed of the first sub-line 50. In the second mode, by using the first sub-line 50 as the sub-line 43, the transmission signal for the second communication band is detected from the high-frequency signals flowing through the main line 42.

[0063] (3.7) High-pass filter High-pass filters 12 and 13 are filters for attenuating unwanted low-frequency signals (including signal components in the ISM (Industrial Scientific and Medical Band) band) from the transmitted and received signals. High-pass filters 12 and 13 have inductors for ESD (Electrostatic Discharge) protection. High-pass filter 12 is connected between terminal 6b of antenna switch 6 and external terminal 5a. High-pass filter 13 is connected between terminal 6c of antenna switch 6 and external terminal 5b. Both the first antenna 3 and the second antenna 4 can be used for transmitting the first transmitted signal in the first communication band and the second transmitted signal in the second communication band. In addition, both the first antenna 3 and the second antenna 4 can be used for receiving the first received signal in the first communication band and the second received signal in the second communication band.

[0064] (3.8) Diplexa The diplexer 14 has multiple (two in the example in Figure 1) receiving filters 14R1 and 14R2. Receiving filter 14R1 is a filter that uses the receiving band of the first communication band as its passband. Receiving filter 14R2 is a filter that uses the receiving band of the second communication band as its passband. Receiving filters 14R1 and 14R2 each have an input section and an output section. The input sections of receiving filter 14R1 and receiving filter 14R2 are shared by a single input section, which is connected to terminal 6d of the antenna switch 6. The output section of receiving filter 14R1 is connected to the input section of the low-noise amplifier 20 via a matching circuit 16. The output section of receiving filter 14R2 is connected to the input section of the low-noise amplifier 21 via a matching circuit 17. Receiving filter 14R1 allows only the signal components in the same frequency band as the first band from the signal (received signal) input to the input section of receiving filter 14R1 to pass through, and outputs the passed signal from the output section of receiving filter 14R1. The receiving filter 14R2 allows only the signal components in the same frequency band as the second communication band from the signal (received signal) input to the receiving filter 14R2 to pass through, and outputs the passed signal from the output section of the receiving filter 14R2.

[0065] The diplexer 15 is configured similarly to the diplexer 14. The diplexer 15 has multiple (two in the example in Figure 1) receiving filters 15R1 and 15R2. Receiving filter 15R1 is a receiving filter that uses the receiving band of the first communication band as its passband. Receiving filter 15R2 is a receiving filter that uses the receiving band of the second communication band as its passband. Receiving filters 15R1 and 15R2 each have an input section and an output section. The input sections of receiving filter 15R1 and receiving filter 15R2 are shared by a single input section, which is connected to terminal 6e of the antenna switch 6. The output section of receiving filter 15R1 is connected to the input section of the low-noise amplifier 22 via a matching circuit 18. The output section of receiving filter 15R2 is connected to the input section of the low-noise amplifier 23 via a matching circuit 19. The receiving filter 15R1 allows only the signal components in the same frequency band as the first communication band from the signal (received signal) input to the receiving filter 15R1 to pass through, and outputs the passed signal from the output of the receiving filter 15R1. The receiving filter 15R2 allows only the signal components in the same frequency band as the second communication band from the signal (received signal) input to the receiving filter 15R2 to pass through, and outputs the passed signal from the output of the receiving filter 15R2.

[0066] (3.9) Low-noise amplifier The low-noise amplifier 20 is connected between the output section of the receiving filter 14R1 and the external terminal 5e, and amplifies the output signal of the receiving filter 14R1. The low-noise amplifier 20 has an input section and an output section. The input section of the low-noise amplifier 20 is connected to the output section of the receiving filter 14R1 via a matching circuit 16. The output section of the low-noise amplifier 20 is connected to the external terminal 5e. The low-noise amplifier 20 amplifies the signal (received signal) input to the input section and outputs the amplified signal from the output section.

[0067] The low-noise amplifier 21 is connected between the output section of the receiving filter 14R2 and the external terminal 5f, and amplifies the output signal of the receiving filter 14R2. The low-noise amplifier 21 has an input section and an output section. The input section of the low-noise amplifier 21 is connected to the output section of the receiving filter 14R2 via a matching circuit 17. The output section of the low-noise amplifier 21 is connected to the external terminal 5f. The low-noise amplifier 21 amplifies the signal (received signal) input to the input section and outputs the amplified signal from the output section.

[0068] The low-noise amplifier 22 is connected between the output section of the receiving filter 15R1 and the external terminal 5g, and amplifies the output signal of the receiving filter 15R1. The low-noise amplifier 22 has an input section and an output section. The input section of the low-noise amplifier 22 is connected to the output section of the receiving filter 15R1 via a matching circuit 18. The output section of the low-noise amplifier 22 is connected to the external terminal 5g. The low-noise amplifier 22 amplifies the signal (received signal) input to the input section and outputs the amplified signal from the output section.

[0069] The low-noise amplifier 23 is connected between the output section of the receiving filter 15R2 and the external terminal 5h, and amplifies the output signal of the receiving filter 15R2. The low-noise amplifier 23 has an input section and an output section. The input section of the low-noise amplifier 23 is connected to the output section of the receiving filter 15R2 via a matching circuit 19. The output section of the low-noise amplifier 23 is connected to the external terminal 5h. The low-noise amplifier 23 amplifies the signal (received signal) input to the input section and outputs the amplified signal from the output section.

[0070] (3.10) Matching circuit Matching circuit 16 is connected between the receiving filter 14R1 and the low-noise amplifier 20 to achieve impedance matching between the receiving filter 14R1 and the low-noise amplifier 20. Matching circuit 17 is connected between the receiving filter 14R2 and the low-noise amplifier 21 to achieve impedance matching between the receiving filter 14R2 and the low-noise amplifier 21. Matching circuit 18 is connected between the receiving filter 15R1 and the low-noise amplifier 22 to achieve impedance matching between the receiving filter 15R1 and the low-noise amplifier 22. Matching circuit 19 is connected between the receiving filter 15R2 and the low-noise amplifier 23 to achieve impedance matching between the receiving filter 15R2 and the low-noise amplifier 23.

[0071] (3.11) Controller The controller 24 controls the electronic components of the high-frequency module 1 (e.g., antenna switch 6, power amplifiers 7, 8, output matching circuit 9, variable low-pass filter 10, multiband coupler 11, matching circuits 16-19, and low-noise amplifiers 20-23) according to the control signals from the signal processing circuit 2. The controller 24 is electrically connected to the above electronic components. The controller 24 is connected to the signal output section of the signal processing circuit 2 via an external terminal 5i. The controller 24 controls each of the above electronic components according to the control signals input from the signal processing circuit 2 to the external terminal 5i.

[0072] (4) Operation of the high-frequency module 1 The operation of the high-frequency module 1 will be explained with reference to Figure 1.

[0073] (4-1) Operation when transmitting the first transmission signal on the first communication band (e.g., n77) When transmitting the first transmission signal in the first communication band, terminal 6a of the antenna switch 6 is connected to one of the two terminals 6b and 6c (for example, terminal 6b). Also, the power to the first drive stage amplifier 71 is turned on, and the power to the second drive stage amplifier 81 is turned off. In addition, the output matching circuit 9 is adjusted so that its matching characteristics correspond to the first communication band by adjusting the capacitance of the variable capacitor C4. For example, the capacitance of the variable capacitor C4 is adjusted to be larger. In addition, the variable low-pass filter 10 is adjusted so that its passband matches the first communication band by adjusting the capacitance of the variable capacitor C5. In addition, the multiband coupler 11 is adjusted so that the sub-line 43 is of a length corresponding to the first communication band (i.e., a series circuit of the first sub-line 50, the first phase shift circuit 45, and the second sub-line 51).

[0074] Then, with each part (antenna switch 6, output matching circuit 9, variable low-pass filter 10, and multi-band coupler 11) adjusted in this manner, the first transmission signal for the first communication band is input from the signal processing circuit 2 to the external terminal 5c. The input first transmission signal is transmitted to the outside from antenna 3 via the first drive stage amplifier 71, matching circuit 73, final stage amplifier 72, output matching circuit 9, variable low-pass filter 10, multi-band coupler 11, antenna switch 6, and high-pass filter 12. At this time, since the matching circuit 73 is, for example, a low-pass filter type matching circuit, it allows signals in the same frequency band as the first communication band to pass through the output signal of the first drive stage amplifier 71, and attenuates signals in the same frequency band as the second communication band (unwanted waves). Therefore, the signal level of signals in the same frequency band as the second communication band that leak back to the matching circuit 83 side as unwanted waves from the output signal of the first drive stage amplifier 71 can be reduced. These unwanted waves generate distortion components in the second drive stage amplifier 81 when the power is turned off, but the matching circuit 73 can suppress the generation of these distortion components. In addition, since the variable capacitor C4 is adjusted so that the output matching characteristics of the output matching circuit 9 correspond to the first communication band, signal loss when the first transmission signal passes through the output matching circuit 9 is further suppressed. Also, since the passband of the variable low-pass filter 10 is adjusted to match the first communication band, signals on the high-frequency side of the first communication band (unwanted waves) are further reduced. Furthermore, since the length of the sub-line 43 of the multi-band coupler 11 is adjusted to a length corresponding to the first communication band, the first transmission signal in the first communication band is effectively detected. In addition, signals on the low-frequency side (unwanted waves) lower than the first transmission signal are reduced by the high-pass filter 12.

[0075] (4-2) Operation when transmitting the second transmission signal on the second communication band (e.g., n79) The operation when transmitting the second transmission signal in the second communication band is the same as when transmitting the first transmission signal in the first communication band, except that the power supply to the first drive stage amplifier 71 is turned off, the power supply to the second drive stage amplifier 81 is turned on, the output matching characteristics of the output matching circuit 9 are adjusted to correspond to the second communication band, the passband of the variable low-pass filter 10 is adjusted to match the second communication band, the sub-line 43 of the multi-band coupler 11 is adjusted to a sub-line of a length corresponding to the second communication band, and the second transmission signal is input from the signal processing circuit 2 to the external terminal 5d instead of the first transmission signal, so a detailed explanation is omitted.Here, the matching circuit 83 is, for example, a high-pass filter type matching circuit, so it passes signals in the same frequency band as the second communication band from the output signal of the second drive stage amplifier 81 and attenuates signals in the same frequency band as the first communication band (unwanted waves). Therefore, the signal level at which unwanted signals in the same frequency band as the first communication band among the output signals of the second drive stage amplifier 81 leak into the matching circuit 73 can be reduced. These unwanted signals generate distortion components in the second drive stage amplifier 81 when the power is turned off, but the matching circuit 83 can suppress the generation of these distortion components.

[0076] (4-3) Operation when receiving the first received signal on the first communication band (e.g., n77) When receiving the first received signal in the first communication band, one receiving terminal (for example, terminal 6b) is selected from terminals 6b and 6c of the antenna switch 6. Also, one connection destination (for example, terminal 6d) is selected from terminals 6d and 6e of the antenna switch 6. Then, the selected terminal 6b is connected to the selected terminal 6d. With this connection, when antenna 3 receives the first received signal in the first communication band, the received first received signal is output to the signal processing circuit 2 from external terminal 5e via the high-pass filter 12, antenna switch 6, receiving filter 14R1, matching circuit 16, and low-noise amplifier 20.

[0077] (4-4) Operation when receiving the second received signal on the second communication band (e.g., n79) When receiving a second received signal in the second communication band, one receiving terminal (for example, terminal 6b) is selected from terminals 6b and 6c of the antenna switch 6. Also, one connection destination (for example, terminal 6d) is selected from terminals 6d and 6e of the antenna switch 6. Then, the selected terminal 6b is connected to the selected terminal 6d. With this connection, when antenna 3 receives a second received signal in the second communication band, the received second received signal is output to the signal processing circuit 2 from external terminal 5f via the high-pass filter 12, antenna switch 6, receiving filter 14R2, matching circuit 17, and low-noise amplifier 21.

[0078] (5) Effects As described above, the high-frequency module 1 according to the embodiment includes a first input section 76, a second input section 77, output sections 78, 79 (first output section), a first drive stage amplifier section 71, a second drive stage amplifier section 81, a final stage amplifier section 72, a first matching circuit 73, and a second matching circuit 83. The first input section 76 receives a first transmission signal in the first communication band. The second input section 77 receives a second transmission signal in the second communication band, which is different from the first communication band. The first drive stage amplifier section 71 is connected downstream of the first input section 76. The second drive stage amplifier section 81 is connected downstream of the second input section 77. The final stage amplifier section 72 is connected upstream of the output sections 78, 79. The first matching circuit 73 is connected between the first drive stage amplifier section 71 and the final stage amplifier section 72 and is a filter-type matching circuit having a first passband including the first communication band and a first attenuation band including the second communication band. The second matching circuit 83 is connected between the second drive stage amplifier 81 and the final stage amplifier 72, and is a filter-type matching circuit having a second passband including the second communication band and a second attenuation band including the first communication band.

[0079] With this configuration, the final stage amplifier 72 for the first communication band and the final stage amplifier 72 for the second communication band, which occupy a large area, are combined into a single final stage amplifier 72, thus enabling miniaturization of the high-frequency module 1.

[0080] Furthermore, since a filter-type first matching circuit 73 is connected between the first drive stage amplifier 71 and the final stage amplifier 72, it is possible to suppress the leakage of unwanted signals from the output signal of the first drive stage amplifier 71 that are in the same frequency band as the second communication band to the second drive stage amplifier 81 side. In other words, the leakage of unwanted signals between power amplifiers 7 and 8 can be suppressed.

[0081] Furthermore, in the high-frequency module 1 according to this embodiment, the frequency band of the second communication band is higher than the frequency band of the first communication band. The first matching circuit 73 is a low-pass filter type matching circuit. The second matching circuit 83 is a high-pass filter type matching circuit. With this configuration, when the frequency band of the second communication band is higher than the frequency band of the first communication band, unwanted waves included in the output signal of the first drive stage amplifier 71 can be attenuated by the first matching circuit 73, thereby preventing leakage of unwanted waves to the second drive stage amplifier 81 side, or unwanted waves included in the output signal of the second drive stage amplifier 81 can be attenuated by the first matching circuit 83, thereby preventing leakage of unwanted waves to the first drive stage amplifier 71 side.

[0082] Furthermore, the high-frequency module 1 according to this embodiment further includes a variable low-pass filter 10. The variable low-pass filter 10 is connected after the output units 78 and 79. The passband of the variable low-pass filter 10 is changed according to the communication band of the transmitted signal output from the output units 78 and 79. With this configuration, the variable low-pass filter 10 can further attenuate unwanted harmonic components contained in the output signals of the output units 78 and 79. In addition, by using the variable low-pass filter 10, it is not necessary to provide a low-pass filter for each communication band, and as a result, the number of low-pass filters can be reduced, making the high-frequency module 1 smaller.

[0083] Furthermore, the high-frequency module 1 according to this embodiment further includes external terminals 5a, 5b (one or more antenna terminals) and an antenna switch 6. The antenna switch 6 is connected to the downstream stage of the variable low-pass filter 10 and to the external terminals 5a, 5b. The variable low-pass filter 10 has a variable capacitor C5. The variable capacitor C5 changes according to the communication band of the transmitted signal output from the output units 78, 79. The variable capacitor C5 is integrated with the antenna switch 6. This configuration allows for miniaturization of the variable low-pass filter 10.

[0084] Furthermore, the high-frequency module 1 according to the embodiment further includes a multiband coupler 11. The multiband coupler 11 is provided in the transmission path TL1 between the variable low-pass filter 10 and the antenna switch 6, and detects the transmission signal passing through the transmission path TL1. The multiband coupler 11 includes a sub-line 43 that is electromagnetically coupled to the transmission path TL1 and whose length can be changed. The multiband coupler 11 detects the transmission signal by changing the length of the sub-line 43 to a length corresponding to the communication band of the transmission signal. With this configuration, by using the multiband coupler 11, transmission signals for multiple communication bands can be detected by a single multiband coupler 11, and the output of the transmission signal can be controlled with high precision for each communication band.

[0085] Furthermore, the high-frequency module 1 according to this embodiment further includes high-pass filters 12 and 13. The high-pass filters 12 and 13 are connected between the antenna switch 6 and the antenna terminals 5a and 5b. With this configuration, the high-pass filters 12 and 13 can attenuate unwanted low-frequency components contained in the transmitted signal.

[0086] Furthermore, the high-frequency module 1 according to the embodiment further comprises an output matching circuit 9. The output matching circuit 9 is connected between the output sections 78, 79 and the variable low-pass filter 10. The final stage amplifier section 72 has a first amplifier section 74 and a second amplifier section 75. The input sections of the first amplifier section 74 and the second amplifier section 75 are connected to each other. The output matching circuit 9 has a transformer 90. The transformer 90 has a balanced coil 91 and an unbalanced coil 92. The balanced coil 91 has a first end 91a and a second end 91b. The first end 91a is connected to the output section of the first amplifier section 74. The second end 91b is connected to the output section of the second amplifier section 75. The unbalanced coil 92 has a third end 92a and a fourth end 92b. The third end 92a is connected to the input section of the variable low-pass filter 10. The fourth end 92b is connected to ground. With this configuration, when the final stage amplifier 72 is a differential amplifier, the high-frequency module 1 can be miniaturized because the final stage amplifier 72 is shared between the power amplifiers 7 and 8. In addition, leakage of unwanted waves between the power amplifiers 7 and 8 can be suppressed.

[0087] Furthermore, the high-frequency module 1 according to the embodiment includes external terminals 5a, 5b (one or more antenna terminals) and an antenna switch 6. The antenna switch 6 is connected to the downstream stage of the variable low-pass filter 10 and to the external terminals 5a, 5b. The output matching circuit 9 further includes a variable capacitor C4. The variable capacitor C4 is connected between the transmission path between the transformer 90 and the variable low-pass filter 10 and the ground. The capacitance of the variable capacitor C4 is changed according to the communication band of the output signals of the output sections 78, 79. The variable capacitor C4 is configured integrally with the antenna switch 6.

[0088] With this configuration, the variable capacitor C4 of the output matching circuit 9 is integrated with the antenna switch 6, allowing the output matching circuit 9 to be miniaturized. Furthermore, since the variable capacitor C4 can be changed according to the communication band of the output signal of the variable low-pass filter 10, the output matching characteristics of the output matching circuit 9 can be changed according to the communication band of the output signal of the variable low-pass filter 10. This allows the output matching characteristics of the output matching circuit 9 to be changed to an optimal value according to the communication band of the output signal of the variable low-pass filter 10.

[0089] Furthermore, in the high-frequency module 1 according to this embodiment, the first communication band is n77, and the second communication band is n79. With this configuration, when the first communication band is n77 and the second communication band is n79, the high-frequency module 1 can be miniaturized, and unwanted wave leakage between the power amplifiers 7 and 8 can be suppressed.

[0090] Furthermore, the communication device 200 according to this embodiment includes a high-frequency module 1 and a signal processing circuit 2. The signal processing circuit 2 is connected to the high-frequency module 1 and processes high-frequency signals. This configuration makes it possible to provide a communication device 200 that takes advantage of the effects of the high-frequency module 1.

[0091] (6) Variant Modifications of the above embodiment will now be described. In the following description, the description of parts that are the same as in the above embodiment will be omitted, and only the parts that differ from the above embodiment will be described. Also, the following modifications can be implemented in combination.

[0092] (6-1) Torture 1 (6-1-1) Composition As shown in Figure 3, in the above embodiment, the output matching circuit 9 further comprises a plurality of inductors L1, L2 (two in the example in Figure 3) and a plurality of switches SW1, SW2.

[0093] Inductor L1 is connected in series via capacitor C6 between the branch point N1 of the transmission path between transformer 90 and variable low-pass filter 10 (more specifically, the transmission path between transformer 90 and capacitor C2) and ground. Inductor L2 is connected in series between branch point N1 and ground. That is, inductor L2 is connected in parallel with inductor L1.

[0094] Multiple switches SW1 and SW2 correspond one-to-one with multiple inductors L1 and L2. Switch SW1 is connected between the corresponding inductor L1 and ground, and switches the conduction and disconnection between inductor L1 and ground. More specifically, when switch SW1 is turned ON, it conducts between inductor L1 and ground, and when switched OFF, it disconnects between inductor L1 and ground. Switch SW2 is connected between the corresponding inductor L2 and ground, and switches the conduction and disconnection between inductor L2 and ground. More specifically, when switch SW2 is turned ON, it conducts between inductor L2 and ground, and when switched OFF, it disconnects between inductor L2 and ground. Switch SW1 is controlled by a control signal from controller 24.

[0095] Switches SW1 and SW2 are located inside the antenna switch 6 and are integrated with the antenna switch 6.

[0096] When transmitting the first transmission signal in the first communication band, for example, switch SW1 is switched ON and switch SW2 is switched OFF. In this case, the inductor of the output matching circuit 9 is composed of inductor L1 of inductors L1 and L2. That is, the inductor of the output matching circuit 9 is changed to the inductor corresponding to the first communication band. Also, when transmitting the second transmission signal in the second communication band, for example, both switches SW1 and SW2 are switched ON. In this case, the inductor of the output matching circuit 9 is composed of a combined inductor of inductors L1 and L2 (inductors L1 and L2 connected in parallel with each other). As a result, the inductor of the output matching circuit 9 is changed to the inductor corresponding to the second communication band.

[0097] (6-1-2) Effects The high-frequency module 1 according to Modification 1 includes external terminals 5a, 5b (one or more antenna terminals) and an antenna switch 6. The antenna switch 6 is connected to the downstream stage of the variable low-pass filter 10 and to the external terminals 5a, 5b. The output matching circuit 9 includes a plurality of inductors L1, L2 and a plurality of switches SW1, SW2. The plurality of inductors L1, L2 are connected between the transmission path between the transformer 90 and the variable low-pass filter 10 and the ground, and are connected in parallel to each other. The plurality of switches SW1, SW2 correspond to the plurality of inductors L1, L2 and conduct and disconnect the corresponding inductor (L1 or L2) and the ground according to the communication band of the output signal of the output section 78, 79. The plurality of switches SW1, SW2 are configured integrally with the antenna switch 6.

[0098] With this configuration, since multiple switches SW1 and SW2 are integrated with the antenna switch 6, the output matching circuit 9 can be miniaturized. Furthermore, because the multiple switches SW1 and SW2 are connected and disconnected according to the communication band of the output signal of the variable low-pass filter 10, the inductor of the entire output matching circuit 9 can be changed according to the communication band of the output signal of the variable low-pass filter 10. As a result, the output matching characteristics of the output matching circuit 9 can be changed according to the communication band of the output signals of the output sections 78 and 79.

[0099] (6-2) Other variations In the above embodiment, the final stage amplifier 72 is exemplified as being composed of two amplifiers 74 and 75 connected in parallel. However, the final stage amplifier 72 may be composed of a single amplifier.

[0100] Furthermore, in the above embodiment, the first power amplifier 7 and the second power amplifier 8 are exemplified as amplifying transmission signals in different communication bands (first communication band and second communication band). However, the first power amplifier 7 and the second power amplifier 8 may constitute a Doherty-type power amplifier. That is, the first power amplifier 7 may be a carrier-type amplifier, and the second power amplifier 8 may be a peak amplifier.

[0101] Furthermore, the above embodiment illustrates a case where multiple antennas (two in Figure 1) are provided. However, there may be only one antenna (for example, only antenna 3). In this case, antenna 4, external terminal 5b, and terminal 6c of the antenna switch 6 are omitted.

[0102] Furthermore, the high-frequency module 1 according to the above embodiment is exemplified as comprising an output matching circuit 9, a variable low-pass filter 10, a multiband coupler 11, and high-pass filters 12, 13. However, it is not necessary for all of these components (output matching circuit 9, variable low-pass filter 10, multiband coupler 11, and high-pass filters 12, 13) to be provided, and they may be provided selectively as needed.

[0103] (Appearance) This specification discloses the following aspects:

[0104] The high-frequency module (1) of the first embodiment includes a first input section (76), a second input section (77), a first output section (78, 79), a first drive stage amplifier section (71), a second drive stage amplifier section (81), a final stage amplifier section (72), a first matching circuit (73), and a second matching circuit (83). The first input section (76) receives a first transmission signal of a first communication band. The second input section (77) receives a second transmission signal of a second communication band different from the first communication band. The first drive stage amplifier section (71) is connected after the first input section (76). The second drive stage amplifier section (81) is connected after the second input section (77). The final stage amplifier section (72) is connected before the first output section (78, 79). The first matching circuit (73) is connected between the first drive stage amplifier (71) and the final stage amplifier (72) and is a filter-type matching circuit having a first passband including the first communication band and a first attenuation band including the second communication band. The second matching circuit (83) is connected between the second drive stage amplifier (81) and the final stage amplifier (72) and is a filter-type matching circuit having a second passband including the second communication band and a second attenuation band including the first communication band.

[0105] With this configuration, the final stage amplifier (72) for the first communication band, which occupies a large area, and the final stage amplifier (72) for the second communication band are both used in a single final stage amplifier (72), thus enabling miniaturization of the high-frequency module (1).

[0106] Furthermore, since a filter-type first matching circuit (73) is connected between the first drive stage amplifier (71) and the final stage amplifier (72), it is possible to suppress the leakage of unwanted signals from the output signal of the first drive stage amplifier (71) that are in the same frequency band as the second communication band to the second drive stage amplifier (81). In other words, the leakage of unwanted signals between the power amplifiers (7,8) can be suppressed.

[0107] In the high-frequency module (1) of the second embodiment, in the first embodiment, the frequency band of the second communication band is higher than the frequency band of the first communication band. The first matching circuit (73) is a low-pass filter type matching circuit. The second matching circuit (83) is a high-pass filter type matching circuit.

[0108] With this configuration, when the frequency band of the second communication hand is higher than the frequency band of the first communication band, it is possible to suppress the leakage of unwanted waves included in the output signal of the first drive stage amplifier (71) to the second drive stage amplifier (81), and vice versa, and vice versa, from the output signal of the second drive stage amplifier (81) to the first drive stage amplifier (71).

[0109] The high-frequency module (1) of the third embodiment further comprises a variable low-pass filter (10) in the first or second embodiment. The variable low-pass filter (10) is connected downstream of the first output section (78, 79). The passband of the variable low-pass filter (10) is changed according to the communication band of the transmitted signal output from the first output section (78, 79).

[0110] With this configuration, the variable low-pass filter (10) can further attenuate unwanted harmonic components contained in the output signal of the output section. In addition, by using the variable low-pass filter (10), it is not necessary to have a low-pass filter for each communication band, and as a result the number of low-pass filters can be reduced, making the high-frequency module (1) smaller.

[0111] The high-frequency module (1) of the fourth embodiment further comprises, in the third embodiment, one or more antenna terminals (5a, 5b) and an antenna switch (6). The antenna switch (6) is connected downstream of the variable low-pass filter (10) and to one or more antenna terminals (5a, 5b). The variable low-pass filter (10) has a variable capacitor (C5). The variable capacitor (C5) changes according to the communication band of the transmitted signal output from the first output section (78, 79). The variable capacitor (C5) is configured integrally with the antenna switch (6).

[0112] This configuration allows for miniaturization of the variable low-pass filter (10).

[0113] The high-frequency module (1) of the fifth embodiment further comprises a multiband coupler (11) in the fourth embodiment. The multiband coupler (11) is provided in the transmission path (TL1) between the variable low-pass filter (10) and the antenna switch (6) and detects the transmission signal passing through the transmission path (TL1). The multiband coupler (11) includes a sub-line (43) that is electromagnetically coupled to the transmission path (TL1) and whose length can be changed. The multiband coupler (11) detects the transmission signal by changing the length of the sub-line (43) to a length corresponding to the communication band of the transmission signal.

[0114] With this configuration, by using a multiband coupler (11), a single coupler (multiband coupler (11)) can detect transmission signals from multiple communication bands, and the output of the transmission signal can be controlled with high precision for each communication band.

[0115] The high-frequency module (1) of the sixth embodiment further comprises high-pass filters (12, 13) in the fourth or fifth embodiment. The high-pass filters (12, 13) are connected between the antenna switch (6) and the antenna terminals (5a, 5b).

[0116] With this configuration, the high-pass filter (12,13) ​​can attenuate unwanted low-frequency components contained in the transmitted signal.

[0117] The seventh embodiment of the high-frequency module (1) further comprises an output matching circuit (9) in any one of the third to sixth embodiments. The output matching circuit (9) is connected between the first output section (78, 79) and the variable low-pass filter (10). The final stage amplifier section (72) has a first amplifier section (74) and a second amplifier section (75). The input sections of the first amplifier section (74) and the second amplifier section (75) are connected to each other. The output matching circuit (9) has a transformer (90). The transformer (90) has a balanced coil (91) and an unbalanced coil (92). The balanced coil (91) has a first end (91a) and a second end (91b). The first end (91a) is connected to the output section of the first amplifier section (74). The second end (91b) is connected to the output section of the second amplifier section (75). The unbalanced coil (92) has a third end (92a) and a fourth end (92b). The third end (92a) is connected to the input of the variable low-pass filter (10). The fourth end (92b) is connected to ground.

[0118] With this configuration, when the final stage amplifier (72) is a differential amplifier, the same effects as those of the first embodiment can be achieved.

[0119] The high-frequency module (1) of the eighth embodiment includes one or more antenna terminals (5a, 5b) and an antenna switch (6) as of the seventh embodiment. The antenna switch (6) is connected to the downstream of the variable low-pass filter (10) and to one or more antenna terminals (5a, 5b). The output matching circuit (9) includes a plurality of inductors (L1, L2) and a plurality of switches (SW1, SW2). The plurality of inductors (L1, L2) are connected in parallel to each other, between the transmission path between the transformer (90) and the variable low-pass filter (10) and the ground. The plurality of switches (SW1, SW2) correspond to the plurality of inductors (L1, L2) and conduct and disconnect the corresponding inductor (L1 or L2) and the ground according to the communication band of the transmission signal output from the first output section (78, 79). The plurality of switches (SW1, SW2) are configured integrally with the antenna switch (6).

[0120] With this configuration, multiple switches (SW1, SW2) are integrated with the antenna switch (6), allowing the output matching circuit (9) to be miniaturized. Furthermore, since the multiple switches (SW1, SW2) are connected and disconnected according to the communication band of the output signal of the variable low-pass filter (10), the total inductor of the output matching circuit (9) can be changed according to the communication band of the output signal of the variable low-pass filter (10). This allows the output matching characteristics of the output matching circuit (9) to be changed according to the communication band of the output signals of the first output sections (78, 79).

[0121] The high-frequency module (1) of the ninth embodiment includes, in the seventh or eighth embodiment, one or more antenna terminals (5a, 5b) and an antenna switch (6). The antenna switch (6) is connected downstream of the variable low-pass filter (10) and to one or more antenna terminals (5a, 5b). The output matching circuit (9) further includes a variable capacitor (C4). The variable capacitor (C4) is connected between the transmission path between the transformer (90) and the variable low-pass filter (10) and ground. The capacitance of the variable capacitor is changed according to the communication band of the transmission signal output from the first output section (78, 79). The variable capacitor (C4) is configured integrally with the antenna switch (6).

[0122] With this configuration, the variable capacitor (C4) of the output matching circuit (9) is integrated with the antenna switch (6), allowing the output matching circuit (9) to be miniaturized. Furthermore, since the variable capacitor (C4) can be changed according to the communication band of the output signal of the variable low-pass filter (10), the output matching characteristics of the output matching circuit (9) can be changed according to the communication band of the output signal of the variable low-pass filter (10). This allows the output matching characteristics of the output matching circuit (9) to be changed to an optimal value according to the communication band of the output signal of the variable low-pass filter (10).

[0123] In the high-frequency module (1) of the tenth embodiment, in any one of the first to ninth embodiments, the first communication band is n77, and the second communication band is n79.

[0124] With this configuration, when the first communication band is n77 and the second communication band is n79, the same effects as those of the first embodiment can be achieved.

[0125] The communication device (200) of the eleventh embodiment comprises a high-frequency module (1) described in any one of the first to tenth embodiments and a signal processing circuit (2). The signal processing circuit (2) is connected to the high-frequency module (1) and processes high-frequency signals.

[0126] This configuration makes it possible to provide a communication device (200) that utilizes the effects of the high-frequency module (1). [Explanation of Symbols]

[0127] 1. High-frequency module 2. Signal Processing Circuit 3. First Antenna 4. Second Antenna 5a External terminal (antenna terminal) 5b External terminal (antenna terminal) 5c~5j External terminals 6. Antenna switch 6a~6e terminal 7. First Power Amplifier 8. Second Power Amplifier 9 Output matching circuit 10 Variable Low-Pass Filter 11 Multiband Coupler 12,13 High-pass filters 14,15 Diplexa 14R1, 14R2, 15R1, 15R2 receiving filter 16~19 Matching circuit 20-23 Low-noise amplifier 24 controllers 30 semiconductor chips 42 Main line 42a 1st end 42b 2nd end 43. Auxiliary track 44 Termination circuit 45 1st phase shift circuit 46. ​​First changeover switch 47. Second changeover switch 48 Termination switches 50 First auxiliary track 50a End 1 50b 2nd end 51 Second auxiliary track 51a 1st end 51b 2nd end 71 First drive stage amplifier 72 Final Stage Amplifier 73 1st matching circuit 73 Matching circuit 74 First Amplifier 75 Second Amplifier 76 First Input Section 77 Second Input Section 78 Output section (First output section) 79 Output section (First output section) 81 Second drive stage amplification section 83 Second matching circuit 83 Matching circuit 90 transformers 91 Balanced coil 91a 1st end 91b 2nd end 91c Intermediate Tap 92 Unbalanced side coil 92a 3rd end 92b 4th end 121 RF signal processing circuit 122 Baseband signal processing circuit 181 First connection terminal 182 Second connection terminal 183 Third connection terminal 200 Communication devices C1~C3 Capacitors C4, C5 Variable Capacitors IC switch L1, L2 Inductors N1 Branch Point RL1 First receiving path RL2 Second receiving path SW1, SW2 switches TL1 transmission path

Claims

1. A first input section into which the first transmission signal of the first communication band is input, A second input section into which a second transmission signal of a second communication band different from the first communication band is input, First output section and The first drive stage amplification section connected to the subsequent stage of the first input section, The second drive stage amplification section connected to the subsequent stage of the second input section, The final stage amplification section connected to the preceding stage of the first output section, A filter-type first matching circuit is connected between the first drive stage amplifier and the final stage amplifier, and has a first passband including the first communication band and a first attenuation band including the second communication band. The system includes a filter-type second matching circuit connected between the second drive stage amplifier and the final stage amplifier, having a second passband including the second communication band and a second attenuation band including the first communication band. High-frequency module.

2. The frequency band of the second communication band is higher than the frequency band of the first communication band. The first matching circuit is a low-pass filter type matching circuit, The second matching circuit is a high-pass filter type matching circuit. The high-frequency module according to claim 1.

3. The first output section is further equipped with a variable low-pass filter connected to the subsequent stage, The passband of the variable low-pass filter is changed according to the communication band of the transmitted signal output from the first output unit. The high-frequency module according to claim 1 or 2.

4. One or more antenna terminals, The system further comprises a stage after the variable low-pass filter and an antenna switch connected to one or more antenna terminals, The variable low-pass filter has a variable capacitor that changes according to the communication band of the transmission signal output from the first output unit, The variable capacitor is configured to be integrated with the antenna switch. The high-frequency module according to claim 3.

5. The transmission path between the variable low-pass filter and the antenna switch is further provided with a multiband coupler that detects the transmission signal passing through the transmission path, The multiband coupler includes a sub-line that is electromagnetically coupled to the transmission path and whose length can be changed. The multiband coupler detects the transmitted signal by changing the length of the sub-line to a length corresponding to the communication band of the transmitted signal. The high-frequency module according to claim 4.

6. The antenna further comprises a high-pass filter connected between the antenna switch and the antenna terminal. The high-frequency module according to claim 4.

7. The output matching circuit is further connected between the first output section and the variable low-pass filter, The final stage amplification section has a first amplification section and a second amplification section. The input sections of the first and second amplification units are connected to each other. The output matching circuit has a transformer, The aforementioned transformer A balanced coil having a first end connected to the output section of the first amplifier and a second end connected to the output section of the second amplifier, The variable low-pass filter has an unbalanced side coil having a third end connected to the input section and a fourth end connected to ground, The high-frequency module according to claim 3.

8. One or more antenna terminals, The system includes a stage after the variable low-pass filter and an antenna switch connected to one or more antenna terminals, The output matching circuit is, A plurality of inductors connected in parallel to each other are connected between the transmission path between the transformer and the variable low-pass filter and the ground, The system includes a plurality of switches corresponding to the plurality of inductors, which connect and disconnect the corresponding inductor and the ground according to the communication band of the transmission signal output from the first output unit, The aforementioned plurality of switches are configured to be integrated with the antenna switch. The high-frequency module according to claim 7.

9. One or more antenna terminals, The system further comprises a stage after the variable low-pass filter and an antenna switch connected to one or more antenna terminals, The output matching circuit further comprises a variable capacitor connected between the transmission path between the transformer and the variable low-pass filter and the ground. The capacitance of the variable capacitor is changed according to the communication band of the transmission signal output from the first output unit. The variable capacitor is configured to be integrated with the antenna switch. The high-frequency module according to claim 7.

10. The first communication band is n77, The aforementioned second communication band is n79. The high-frequency module according to claim 1 or 2.

11. A high-frequency module according to claim 1 or 2, The system includes a signal processing circuit connected to the aforementioned high-frequency module for processing high-frequency signals. Communication device.

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