High-frequency circuit and communication device

Abstract

This high frequency circuit (1) comprises: a switch circuit (51) that includes common terminals (511 and 512) respectively connected to antenna connection terminals (101 and 102) and selection terminals (513, 514, and 515); a switch circuit (52) that includes selection terminals (523 and 524) respectively connected to common terminals (521 and 522) and low-noise amplifiers (22 and 23), and a selection terminal (525) connected to a power amplifier (12); a filter (31) for the reception band of an FDD band A connected between the selection terminal (513) and a low-noise amplifier (21); a filter (32) for the transmission band of the FDD band A connected between the selection terminal (513) and a power amplifier (11); a filter (33) for a TDD band B connected between the selection terminal (514) and the common terminal (521); and a filter (34) for the TDD band B connected between the selection terminal (515) and the common terminal (522).

Description

High frequency circuits and communication devices

[0001] The present invention relates to a high-frequency circuit and a communication device.

[0002] Mobile communication devices such as mobile phones are required to support carrier aggregation (CA), multiple-input and multiple-output (MIMO), etc. Patent Document 1 discloses a high-frequency module capable of simultaneous communication of signals in a frequency division duplex (FDD) band and signals in a time division duplex (TDD) band.

[0003] International Publication No. 2021 / 131223

[0004] However, if the above-mentioned conventional technology is adapted to MIMO, there are concerns that the communication device will become larger and communication quality will deteriorate.

[0005] Therefore, the present invention provides a high-frequency circuit and a communication device that can suppress an increase in size of a communication device compatible with CA and MIMO and a decrease in communication quality.

[0006] A high-frequency circuit according to one aspect of the present invention includes a first power amplifier and a second power amplifier, a first low-noise amplifier, a second low-noise amplifier and a third low-noise amplifier, a first antenna connection terminal and a second antenna connection terminal, a first switch circuit including a first common terminal connected to the first antenna connection terminal, a second common terminal connected to the second antenna connection terminal, and a first selection terminal, a second selection terminal and a third selection terminal, a second switch circuit including a third common terminal and a fourth common terminal, a fourth selection terminal connected to the second low-noise amplifier, a fifth selection terminal connected to the third low-noise amplifier and a sixth selection terminal connected to the second power amplifier, a first filter connected between the first selection terminal and the first low-noise amplifier and having a passband including a reception band of the FDD band, and a second filter connected between the first selection terminal and the first power amplifier. a second filter connected between the second selection terminal and the third common terminal and having a passband including the TDD band; a third filter connected between the second selection terminal and the third common terminal and having a passband including the TDD band; and a fourth filter connected between the third selection terminal and the fourth common terminal and having a passband including the TDD band, wherein in a first mode for transmitting and receiving signals in the FDD band and receiving MIMO signals in the TDD band, the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal and connects the second common terminal to the third selection terminal, and the second switch circuit connects the third common terminal to the fourth selection terminal and connects the fourth common terminal to the fifth selection terminal, to receive signals in the FDD band and to receive sounding reference signals (SRS) in the TDD band. In a second mode for receiving a signal in the FDD band and transmitting an SRS in the TDD band via the second antenna connection terminal, the first switch circuit connects the first common terminal to the first and second selection terminals, and the second switch circuit connects the third common terminal to the sixth selection terminal. In a third mode for receiving a signal in the FDD band and transmitting an SRS in the TDD band via the second antenna connection terminal, the first switch circuit connects the first common terminal to the first and second selection terminals and connects the second common terminal to the third selection terminal, and the second switch circuit connects the fourth common terminal to the sixth selection terminal.

[0007] A communication device according to one aspect of the present invention comprises a signal processing circuit configured to process high-frequency signals, and the high-frequency circuit configured to transmit high-frequency signals between the signal processing circuit and a first antenna and a second antenna, wherein the first antenna connection terminal is connected to the first antenna and the second antenna connection terminal is connected to the second antenna.

[0008] According to the present invention, it is possible to suppress an increase in size of a communication device that is compatible with CA and MIMO and a decrease in communication quality.

[0009] FIG. 1 is a basic configuration diagram of a communication device according to a first embodiment. FIG. 2 is a circuit configuration diagram of a portion of the communication device according to the first embodiment. FIG. 3 is a diagram illustrating a first mode of the high-frequency circuit according to the first embodiment. FIG. 4 is a diagram illustrating a second mode of the high-frequency circuit according to the first embodiment. FIG. 5 is a diagram illustrating a third mode of the high-frequency circuit according to the first embodiment. FIG. 6 is a circuit configuration diagram of a communication device according to a second embodiment. FIG. 7 is a diagram illustrating the first mode of the high-frequency circuit according to the second embodiment. FIG. 8 is a diagram illustrating the second mode of the high-frequency circuit according to the second embodiment. FIG. 9 is a diagram illustrating the third mode of the high-frequency circuit according to the second embodiment. FIG. 10 is a circuit configuration diagram of a communication device according to a third embodiment. FIG. 11 is a diagram illustrating the first mode of the high-frequency circuit according to the third embodiment. FIG. 12 is a diagram illustrating the second mode of the high-frequency circuit according to the third embodiment. FIG. 13 is a diagram illustrating the third mode of the high-frequency circuit according to the third embodiment. FIG. 14 is a circuit configuration diagram of a high-frequency circuit according to a fourth embodiment.

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, arrangements and connection forms of the components shown in the following embodiments are merely examples and are not intended to limit the present invention.

[0011] It should be noted that the drawings are schematic diagrams in which emphasis, omission, or adjustment of proportions has been appropriately made to illustrate the present invention, and are not necessarily strictly illustrated, and may differ from the actual shapes, positional relationships, and proportions. In the drawings, the same reference numerals are used to denote substantially the same components, and redundant explanations may be omitted or simplified.

[0012] In the following description, "connected" includes not only direct connection by connection terminals and / or wiring conductors, but also electrical connection via other circuit elements. "C is connected between A and B" means that one end of C is connected to A and the other end of C is connected to B, and that they are arranged in series on a path connecting A and B. "A path connecting A and B" means a path made up of a conductor electrically connecting A to B.

[0013] "Terminal" means a point where a conductor within an element terminates. Note that terminal is interpreted as any point on the conductor between elements or the entire conductor, not just a single point, provided the impedance of the conductor between elements is sufficiently low.

[0014] The "filter passband" is the portion of the frequency spectrum transmitted by the filter, defined as the frequency band between two frequencies 3 dB above the minimum power insertion loss.

[0015] The term "transmission band" refers to a frequency band used for transmission in a communication device, and the term "reception band" refers to a frequency band used for reception in a communication device. For example, in an FDD band, different frequency bands (uplink band and downlink band) are used as the transmission band and the reception band. For example, in a TDD band, the same frequency band is used as the transmission band and the reception band.

[0016] The "size of an acoustic wave filter" refers to the area of ​​a region in which acoustic wave resonators are formed in a plan view of the acoustic wave filter. For example, the size of a surface acoustic wave (SAW) filter is expressed by the area of ​​a region in which interdigital transducers (IDTs) are arranged on a piezoelectric substrate. Similarly, the size of a bulk acoustic wave (BAW) filter is expressed by the area of ​​a piezoelectric element arranged between an upper electrode and a lower electrode.

[0017] "Attenuation in a given band of a filter" refers to the maximum attenuation of the filter in the given band. Here, attenuation is expressed as the absolute value (dB) of 10 times the common logarithm of the ratio of output power to input power. When the power of the input signal to the filter is constant, the attenuation increases as the power of the output signal from the filter decreases.

[0018] Terms indicating the relationship between elements, such as "parallel" and "perpendicular," terms indicating the shape of elements, such as "rectangle," and numerical ranges do not only indicate the strict meaning, but also include a substantially equivalent range, for example, an error of a few percent.

[0019] (Embodiment 1) [1.1. Basic Configuration of Communication Device 7] First, an exemplary basic configuration of a communication device 7 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing the basic configuration of a communication device 7 according to this embodiment. In Fig. 1, a dashed line in a switch circuit represents a path between two terminals that can be switched between connected and disconnected states.

[0020] 1 is an exemplary basic block diagram, and the communication device 7 may be implemented using any of a wide variety of circuit implementations and circuit technologies. Therefore, the description of the communication device 7 provided below should not be construed as limiting.

[0021] The communication device 7 according to the present embodiment can be used to provide wireless connectivity. For example, the communication device 7 can be implemented in user equipment (UE) in a cellular network (also referred to as a mobile network), such as a mobile phone, a smartphone, a tablet computer, or a wearable device. In another example, the communication device 7 can be implemented to provide wireless connectivity to Internet of Things (IoT) sensor devices, medical / healthcare devices, cars, unmanned aerial vehicles (UAVs) (also known as drones), and automated guided vehicles (AGVs). In yet another example, the communication device 7 can be implemented to provide wireless connectivity in a wireless access point or a wireless hotspot.

[0022] The communication device 7 includes high-frequency circuits 1, 2, and 3, antennas 4a, 4b, 4c, and 4d, a Radio Frequency Integrated Circuit (RFIC) 5, and a Baseband Integrated Circuit (BBIC) 6. The high-frequency circuit 1 and the antennas 4a and 4b are included in a main module, and the high-frequency circuits 2 and 3 and the antennas 4c and 4d are included in a diver module. Note that the RFIC 5 and the BBIC 6 are provided in common to the main module and the diver module, but they may also be provided separately for the main module and the diver module, or may be provided for each high-frequency circuit.

[0023] The high-frequency circuit 1 can transmit high-frequency signals between the antennas 4a and 4b and the RFIC 5. The high-frequency circuit 1 can also supply a sounding reference signal (SRS) to the high-frequency circuits 2 and 3. The circuit configuration of the high-frequency circuit 1 will be described later with reference to FIG. 2 .

[0024] The SRS is a reference signal transmitted from a UE to a base station (BS) for each antenna to measure channel quality. The BS estimates channel quality including spatial propagation conditions (channel matrix) using the SRS received from the UE, and determines various parameters (e.g., precoding weight, channel power allocation, etc.) used in DL-MIMO based on the estimation result.

[0025] The high-frequency circuit 2 can transmit high-frequency signals between the antenna 4c and the RFIC 5. The high-frequency circuit 3 can transmit high-frequency signals between the antenna 4d and the RFIC 5. Although detailed configurations of the high-frequency circuits 2 and 3 are not shown or described, they may be the same as the high-frequency circuits included in conventional diver modules and MIMO modules. Furthermore, the high-frequency circuits 2 and 3 may be integrated into a single high-frequency circuit and may not be included in the communication device 7.

[0026] Antennas 4a and 4b are connected to high-frequency circuit 1, antenna 4c is connected to high-frequency circuit 2, and antenna 4d is connected to high-frequency circuit 3. Antennas 4a to 4d can receive high-frequency signals from high-frequency circuits 1 to 3 and transmit them to the outside of communication device 7. Furthermore, antennas 4a to 4d can receive high-frequency signals from the outside of communication device 7 and supply them to high-frequency circuits 1 to 3. Note that some or all of antennas 4a to 4d do not need to be included in communication device 7. Furthermore, communication device 7 may include one or more antennas in addition to antennas 4a to 4d.

[0027] The RFIC 5 is an example of a signal processing circuit that processes high-frequency signals. Specifically, the RFIC 5 can perform signal processing on a transmission signal input from the BBIC 6 by up-conversion or the like, and output the high-frequency transmission signal generated by the signal processing to the high-frequency circuit 1. Furthermore, the RFIC 5 can also perform signal processing on a high-frequency reception signal input via the reception path of the high-frequency circuits 1 to 3 by down-conversion or the like, and output the reception signal generated by the signal processing to the BBIC 6. The RFIC 5 may also have a control unit that controls the switches, power amplifiers, etc. of the high-frequency circuits 1 to 3. Note that some or all of the functions of the RFIC 5 as a control unit may be included outside the RFIC 5, and may be included in the BBIC 6 or the high-frequency circuits 1 to 3, for example.

[0028] The BBIC 6 is a baseband signal processing circuit that processes signals using a frequency band lower than the high-frequency signals transmitted by the high-frequency circuits 1 to 3. The signals processed by the BBIC 6 include, for example, image signals for image display and / or audio signals for calls via a speaker. The BBIC 6 does not necessarily have to be included in the communication device 7.

[0029] [1.2. Circuit Configuration of High-Frequency Circuit 1] Next, an exemplary circuit configuration of the high-frequency circuit 1 according to this embodiment will be described with reference to Fig. 2. Fig. 2 is a circuit configuration diagram of a portion of the communication device 7 according to this embodiment. Specifically, Fig. 2 is a circuit configuration diagram of a main module of the communication device 7 according to this embodiment.

[0030] 2 is an exemplary circuit diagram, and the high-frequency circuit 1 can be implemented using any of a wide variety of circuit implementations and circuit technologies. Therefore, the description of the high-frequency circuit 1 provided below should not be construed as limiting.

[0031] The high-frequency circuit 1 includes power amplifiers 11 and 12, low-noise amplifiers 21, 22 and 23, filters 31, 32, 33 and 34, switch circuits 51 and 52, antenna connection terminals 101 and 102, high-frequency input terminals 111 and 112, high-frequency output terminals 121, 122 and 123, and an SRS output terminal 131.

[0032] The antenna connection terminals 101 and 102 are examples of a first antenna connection terminal and a second antenna connection terminal, respectively, and are external connection terminals of the high-frequency circuit 1. The antenna connection terminals 101 and 102 are connected to the antennas 4a and 4b, respectively, outside the high-frequency circuit 1, and are connected to the switch circuit 51 inside the high-frequency circuit 1.

[0033] The radio frequency input terminals 111 and 112 are external connection terminals of the radio frequency circuit 1, and are connected to the RFIC 5 outside the radio frequency circuit 1, and are connected to the power amplifiers 11 and 12 inside the radio frequency circuit 1, respectively.

[0034] High frequency output terminals 121, 122 and 123 are external connection terminals of the high frequency circuit 1, connected to the RFIC 5 outside the high frequency circuit 1, and connected to low noise amplifiers 21, 22 and 23 inside the high frequency circuit 1, respectively.

[0035] The SRS output terminal 131 is an external connection terminal of the high frequency circuit 1 , and is connected to the high frequency circuits 2 and 3 outside the high frequency circuit 1 , and is connected to the switch circuit 52 inside the high frequency circuit 1 .

[0036] The power amplifier 11 is an example of a first power amplifier, and is connected between the radio frequency input terminal 111 and the filter 32. Specifically, the input terminal of the power amplifier 11 is connected to the radio frequency input terminal 111, and the output terminal of the power amplifier 11 is connected to the filter 32. The power amplifier 11 can amplify a transmission signal (A-Tx) of band A using power supplied from a power supply (not shown).

[0037] The power amplifier 12 is an example of a second power amplifier, and is connected between the radio frequency input terminal 112 and the switch circuit 52. Specifically, the input terminal of the power amplifier 12 is connected to the radio frequency input terminal 112, and the output terminal of the power amplifier 12 is connected to the switch circuit 52. The power amplifier 12 can amplify a transmission signal (B-Tx) of band B using power supplied from a power supply (not shown).

[0038] The power amplifiers 11 and 12 may be configured with heterojunction bipolar transistors (HBTs) and may be manufactured using semiconductor materials. Examples of the semiconductor materials that may be used include silicon germanium (SiGe) and gallium arsenide (GaAs). The amplifying transistors of the power amplifiers 11 and 12 are not limited to HBTs. For example, the power amplifiers 11 and 12 may be configured with high electron mobility transistors (HEMTs) or metal-semiconductor field effect transistors (MESFETs). In this case, gallium nitride (GaN) or silicon carbide (SiC) may be used as the semiconductor material. Furthermore, part or all of each of the power amplifiers 11 and 12 may be configured with complementary metal oxide semiconductors (CMOSs) or may be manufactured using a silicon-on-insulator (SOI) process. In this case, silicon (Si) may be used as the semiconductor material.

[0039] The low-noise amplifier 21 is an example of a first low-noise amplifier, and is connected between the filter 31 and the high-frequency output terminal 121. Specifically, the input terminal of the low-noise amplifier 21 is connected to the filter 31, and the output terminal of the low-noise amplifier 21 is connected to the high-frequency output terminal 121. The low-noise amplifier 21 can amplify the band A reception signal (A-Rx) using power supplied from a power supply (not shown).

[0040] The low-noise amplifier 22 is an example of a second low-noise amplifier, and is connected between the switch circuit 52 and the high-frequency output terminal 122. Specifically, the input terminal of the low-noise amplifier 22 is connected to the switch circuit 52, and the output terminal of the low-noise amplifier 22 is connected to the high-frequency output terminal 122. The low-noise amplifier 22 can amplify the band B reception signal (B-Rx) using power supplied from a power supply (not shown).

[0041] The low-noise amplifier 23 is an example of a third low-noise amplifier, and is connected between the switch circuit 52 and the high-frequency output terminal 123. Specifically, the input terminal of the low-noise amplifier 23 is connected to the switch circuit 52, and the output terminal of the low-noise amplifier 23 is connected to the high-frequency output terminal 123. The low-noise amplifier 23 can amplify the band B reception signal (B-Rx) using power supplied from a power supply (not shown).

[0042] The low-noise amplifiers 21 to 23 may be configured with field-effect transistors (FETs) and may be manufactured using semiconductor materials. Examples of the semiconductor materials that may be used include silicon monocrystal (Si), gallium nitride (GaN), and silicon carbide (SiC). The amplifying transistors of the low-noise amplifiers 21 to 23 are not limited to FETs. For example, some or all of the low-noise amplifiers 21 to 23 may be configured with bipolar transistors.

[0043] The filter 31 is an example of a first filter, and is a bandpass filter having a passband that includes the receive band of band A. The filter 31 passes the receive signal (A-Rx) of band A and can attenuate the transmit signal (A-Tx) of band A and signals of other bands. The filter 31 is connected between the switch circuit 51 and the low-noise amplifier 21. Specifically, one end of the filter 31 is connected to the selection terminal 513 of the switch circuit 51, and the other end of the filter 31 is connected to the input terminal of the low-noise amplifier 21.

[0044] The filter 32 is an example of a second filter, and is a band-pass filter having a passband that includes the transmission band of band A. The filter 32 passes a transmission signal (A-Tx) of band A and attenuates a reception signal (A-Rx) of band A and signals of other bands. The filter 32 is connected between the power amplifier 11 and the switch circuit 51. Specifically, one end of the filter 32 is connected to the output terminal of the power amplifier 11, and the other end of the filter 32 is connected to a selection terminal 513 of the switch circuit 51.

[0045] Band A is a frequency band for communication systems built using radio access technology (RAT), and is defined in advance by standardization organizations (e.g., 3GPP (registered trademark) (3rd Generation Partnership Project) and IEEE (Institute of Electrical and Electronics Engineers)). Examples of communication systems include 5GNR (5th Generation New Radio) systems, LTE (Long Term Evolution) systems, and WLAN (Wireless Local Area Network) systems.

[0046] Specifically, Band A is an FDD band, such as Band 1, Band 3, Band 25, or Band 66 for LTE, or n1, n3, n25, or n66 for 5G NR. Note that Band A is not limited to the frequency bands exemplified here.

[0047] The filter 33 is an example of a third filter, and is a band-pass filter having a passband that includes the transmission band and reception band of band B. The filter 33 passes transmission signals and reception signals (B-TRx) of band B and attenuates signals of other bands, and can be used for transmitting and receiving signals of band B. The filter 33 is connected between the switch circuits 51 and 52. Specifically, one end of the filter 33 is connected to the selection terminal 514 of the switch circuit 51, and the other end of the filter 33 is connected to the common terminal 521 of the switch circuit 52.

[0048] The filter 34 is an example of a fourth filter, and is a bandpass filter having a passband that includes the transmission band and reception band of band B. The filter 34 passes transmission signals and reception signals (B-TRx) of band B and attenuates signals of other bands, and can be used to transmit SRS of band B and receive MIMO signals. The filter 34 is connected between the switch circuits 51 and 52. Specifically, one end of the filter 34 is connected to the selection terminal 515 of the switch circuit 51, and the other end of the filter 34 is connected to the common terminal 522 of the switch circuit 52.

[0049] Like band A, band B is a frequency band for a communication system built using a RAT, and is predefined by a standardization organization (e.g., 3GPP, IEEE, etc.). Examples of the communication system include a 5G NR system, an LTE system, and a WLAN system.

[0050] Specifically, Band B is a TDD band, such as Band 40 or Band 41 for LTE, or n40 or n41 for 5G NR. Note that Band B is not limited to the frequency bands exemplified here.

[0051] The filters 31 to 34 may be, but are not limited to, SAW filters, BAW filters, LC resonant filters, dielectric resonant filters, or any combination thereof.

[0052] The attenuation of the filter 33 in the reception band of band A is greater than the attenuation of the filter 34 in the reception band of band A. When the filters 33 and 34 are acoustic wave filters, the number of resonators in the filter 33 is greater than the number of resonators in the filter 34. As a result, the size of the filter 33 is greater than the size of the filter 34.

[0053] The switch circuit 51 is an example of a first switch circuit and is connected between the antenna connection terminals 101 and 102 and the filters 31 to 34. The switch circuit 51 includes common terminals 511 and 512 and selection terminals 513, 514, and 515. The common terminal 511 is an example of a first common terminal and is connected to the antenna connection terminal 101. The common terminal 512 is an example of a second common terminal and is connected to the antenna connection terminal 102. The selection terminal 513 is an example of a first selection terminal and is connected to the filters 31 and 32. The selection terminal 514 is an example of a second selection terminal and is connected to the filter 33. The selection terminal 515 is an example of a third selection terminal and is connected to the filter 34.

[0054] In such a connection configuration, the switch circuit 51 can connect the common terminal 511 to at least the selection terminals 513 and 514, and can connect the common terminal 512 to at least the selection terminal 515, based on, for example, a control signal from the RFIC 5.

[0055] The switch circuit 52 is an example of a second switch circuit and is connected between the filters 33 and 34 and the power amplifier 12 and the low-noise amplifiers 22 and 23. The switch circuit 52 includes common terminals 521, 522, and 526 and selection terminals 523, 524, and 525. The common terminal 521 is an example of a third common terminal and is connected to the filter 33. The common terminal 522 is an example of a fourth common terminal and is connected to the filter 34. The selection terminal 523 is an example of a fourth selection terminal and is connected to the input terminal of the low-noise amplifier 22. The selection terminal 524 is an example of a fifth selection terminal and is connected to the input terminal of the low-noise amplifier 23. The selection terminal 525 is an example of a sixth selection terminal and is connected to the output terminal of the power amplifier 12. The common terminal 526 is connected to the SRS output terminal 131. Note that the common terminal 526 does not have to be included in the switch circuit 51.

[0056] In such a connection configuration, the switch circuit 52 can connect the common terminal 521 to at least the selection terminals 523 and 525, can connect the common terminal 522 to at least the selection terminals 524 and 525, and can connect the common terminal 526 to at least the selection terminal 525, for example, based on a control signal from the RFIC 5.

[0057] [1.3. Multiple Communication Modes] Next, multiple communication modes of the high-frequency circuit 1 will be described.

[0058] [1.3.1. First Mode] First, the first mode included in the multiple communication modes will be described with reference to Fig. 3. Fig. 3 is a diagram showing the first mode of the high-frequency circuit 1 according to this embodiment. In the following figures, dashed arrows represent transmission paths and reception paths of high-frequency signals, and solid lines within the switch circuit represent paths between terminals that are connected to each other.

[0059] The first mode is a communication mode for transmitting and receiving signals of band A and receiving MIMO signals of band B. Switch circuit 51 connects common terminal 511 to selection terminals 513 and 514, and connects common terminal 512 to selection terminal 515. Switch circuit 52 connects common terminal 521 to selection terminal 523, and connects common terminal 522 to selection terminal 524.

[0060] As a result, the band A transmission signal is transmitted from the RFIC 5 to the antenna 4a via the radio frequency input terminal 111, the power amplifier 11, the filter 32, the switch circuit 51, and the antenna connection terminal 101. The band A reception signal is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51, the filter 31, the low noise amplifier 21, and the radio frequency output terminal 121. One of the band B MIMO reception signals is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51, the filter 33, the switch circuit 52, the low noise amplifier 22, and the radio frequency output terminal 122. The other of the band B MIMO reception signals is transmitted from the antenna 4b to the RFIC 5 via the antenna connection terminal 102, the switch circuit 51, the filter 34, the switch circuit 52, the low noise amplifier 23, and the radio frequency output terminal 123.

[0061] [1.3.2. Second Mode] Next, the second mode included in the plurality of communication modes will be described with reference to Fig. 4. Fig. 4 is a diagram showing the second mode of the high-frequency circuit 1 according to this embodiment.

[0062] The second mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 101 and the antenna 4a. The switch circuit 51 connects the common terminal 511 to the selection terminals 513 and 514. The switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0063] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4a via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 33, the switch circuit 51, and the antenna connection terminal 101.

[0064] [1.3.3. Third Mode] Next, a third mode included in the plurality of communication modes will be described with reference to Fig. 5. Fig. 5 is a diagram showing the third mode of the high-frequency circuit 1 according to this embodiment.

[0065] The third mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 102 and the antenna 4b. The switch circuit 51 connects the common terminal 511 to the selection terminals 513 and 514, and connects the common terminal 512 to the selection terminal 515. The switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0066] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4b via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 34, the switch circuit 51, and the antenna connection terminal 102.

[0067] In this way, in all of the first to third modes, the common terminal 511 of the switch circuit 51 is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, and makes it possible to suppress deterioration of the reception characteristics of band A due to SRS transmission of band B (for example, a decrease in throughput).

[0068] The multiple communication modes of the high-frequency circuit 1 may include other modes in addition to the first to third modes. For example, the multiple communication modes of the high-frequency circuit 1 may include a fourth mode for receiving a signal in band A and supplying an SRS in band B to the high-frequency circuits 2 and / or 3. In the fourth mode, the switch circuit 51 may connect the common terminal 511 to the selection terminals 513 and 514, and the switch circuit 52 may connect the common terminal 526 to the selection terminal 525. Furthermore, for example, the multiple communication modes of the high-frequency circuit 1 may include a fifth mode for transmitting and receiving a signal in band B. In the fifth mode, the switch circuit 51 may connect the common terminal 511 to the selection terminal 514, but may not connect the common terminal 511 to the selection terminal 513, and the switch circuit 52 may switch the connection of the common terminal 521 between the selection terminals 523 and 525. The multiple communication modes of the high-frequency circuit 1 may include communication modes different from the fourth and fifth modes.

[0069] [1.4. Summary] As described above, the high-frequency circuit 1 according to this embodiment includes the power amplifiers 11 and 12, the low-noise amplifiers 21, 22, and 23, the antenna connection terminals 101 and 102, the switch circuit 51 including the common terminal 511 connected to the antenna connection terminal 101, the common terminal 512 connected to the antenna connection terminal 102, and the selection terminals 513, 514, and 515, the common terminals 521 and 522, the selection terminal 523 connected to the low-noise amplifier 22, the selection terminal 524 connected to the low-noise amplifier 23, and the selection terminal 525 connected to the power amplifier 12. a filter 31 connected between the selection terminal 513 and the low-noise amplifier 21 and having a passband including the reception band of band A, which is an FDD band; a filter 32 connected between the selection terminal 513 and the power amplifier 11 and having a passband including the transmission band of band A; a filter 33 connected between the selection terminal 514 and the common terminal 521 and having a passband including the transmission band and reception band of band B, which is a TDD band; and a filter 34 having a passband including a transmit band, and in a first mode for transmitting and receiving a signal of band A and receiving a MIMO signal of band B, the switch circuit 51 connects the common terminal 511 to a selection terminal 513 and a selection terminal 514 and connects the common terminal 512 to a selection terminal 515, and the switch circuit 52 connects the common terminal 521 to a selection terminal 523 and connects the common terminal 522 to a selection terminal 524, and is configured to receive a signal of band A and transmit an SRS of band B via the antenna connection terminal 101. In a second mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 102, the switch circuit 51 connects the common terminal 511 to the selection terminal 513 and the selection terminal 514, and the switch circuit 52 connects the common terminal 521 to the selection terminal 525. In a third mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 102, the switch circuit 51 connects the common terminal 511 to the selection terminal 513 and the selection terminal 514 and connects the common terminal 512 to the selection terminal 515, and the switch circuit 52 connects the common terminal 522 to the selection terminal 525.

[0070] According to this, by using the first mode, the high-frequency circuit 1 can support interband CA of bands A and B and MIMO of band B. Furthermore, by using the second and third modes, the high-frequency circuit 1 can transmit SRS from each antenna while receiving a band A signal. At this time, in all of the first to third modes, the common terminal 511 of the switch circuit 51 is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained within the switch circuit 51. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, thereby suppressing deterioration of the reception characteristics of band A (e.g., a decrease in throughput) due to SRS transmission of band B. Furthermore, the filter 34 is used both for receiving MIMO signals of band B and for transmitting SRS of band B. Therefore, the high-frequency circuit 1 can reduce the number of filters compared to when a filter for receiving MIMO signals of band B and a filter for transmitting SRS of band B are provided separately, thereby preventing the communication device 7 from becoming larger.

[0071] Furthermore, for example, in the high-frequency circuit 1 according to this embodiment, each of the filters 33 and 34 may be an acoustic wave filter, and the size of the filter 33 may be larger than the size of the filter 34 .

[0072] According to this, by making the size of filter 33 larger than the size of filter 34, it is possible to ensure sufficient attenuation of filter 33 in the passbands of filters 31 and 32, which are connected to antenna connection terminal 101 simultaneously with filter 33. Therefore, it is possible to improve communication quality in the first mode in which transmission and reception of signals in band A and reception of MIMO signals in band B are performed simultaneously.

[0073] Furthermore, for example, in the high-frequency circuit 1 according to this embodiment, the attenuation of the filter 33 in the reception band of band A may be greater than the attenuation of the filter 34 in the reception band of band A.

[0074] This makes it possible to improve communication quality in the first mode in which the filters 31, 32, and 33 are simultaneously connected to the antenna connection terminal 101.

[0075] Also, for example, in the high-frequency circuit 1 according to this embodiment, band A may be Band 1, Band 3, Band 25, or Band 66 for LTE, or n1, n3, n25, or n66 for 5G NR, and band B may be Band 40 or Band 41 for LTE, or n40 or n41 for 5G NR.

[0076] This allows the high-frequency circuit 1 to be compatible with 5G NR and / or LTE.

[0077] In addition, the communication device 7 according to this embodiment includes an RFIC 5 configured to process high-frequency signals, and a high-frequency circuit 1 configured to transmit high-frequency signals between the RFIC 5 and antennas 4a and 4b, and the antenna connection terminal 101 is connected to the antenna 4a, and the antenna connection terminal 102 is connected to the antenna 4b.

[0078] This allows the effects of the high frequency circuit 1 to be realized in the communication device 7.

[0079] (Embodiment 2) Next, embodiment 2 will be described. This embodiment differs from embodiment 1 above mainly in that it supports MIMO of band A in addition to MIMO of band B. Hereinafter, this embodiment will be described with reference to the drawings, focusing on the differences from embodiment 1 above.

[0080] A communication device 7A according to this embodiment is similar to the first embodiment except that it includes a high-frequency circuit 1A instead of the high-frequency circuit 1, and therefore illustration and description of its basic configuration will be omitted.

[0081] [2.1. Circuit Configuration of High-Frequency Circuit 1A] An exemplary circuit configuration of the high-frequency circuit 1A according to this embodiment will be described with reference to Fig. 6. Fig. 6 is a circuit configuration diagram of a portion of a communication device 7A according to this embodiment. Specifically, Fig. 6 is a circuit configuration diagram of a main module of the communication device 7A according to this embodiment.

[0082] 6 is an exemplary circuit diagram, and the high-frequency circuit 1A can be implemented using any of a wide variety of circuit implementations and circuit technologies. Therefore, the description of the high-frequency circuit 1A provided below should not be construed as limiting.

[0083] The high-frequency circuit 1A includes power amplifiers 11 and 12, low-noise amplifiers 21, 22, 23 and 24, filters 31, 32, 33, 34 and 35, switch circuits 51A and 52, antenna connection terminals 101 and 102, high-frequency input terminals 111 and 112, high-frequency output terminals 121, 122, 123 and 124, and an SRS output terminal 131.

[0084] The high frequency output terminal 124 is an external connection terminal of the high frequency circuit 1A, and is connected to the RFIC 5 outside the high frequency circuit 1A, and is connected to the low noise amplifier 24 inside the high frequency circuit 1A.

[0085] The low-noise amplifier 24 is an example of a fourth low-noise amplifier, and is connected between the filter 35 and the high-frequency output terminal 124. Specifically, the input terminal of the low-noise amplifier 24 is connected to the filter 35, and the output terminal of the low-noise amplifier 24 is connected to the high-frequency output terminal 124. The low-noise amplifier 24 can amplify the received signal of Band A using power supplied from a power supply (not shown).

[0086] The filter 35 is an example of a fifth filter, and is a bandpass filter having a passband that includes the reception band of band A. The filter 35 is a filter for receiving MIMO signals of band A, and is connected between the switch circuit 51A and the low-noise amplifier 24. Specifically, one end of the filter 35 is connected to the selection terminal 516 of the switch circuit 51A, and the other end of the filter 35 is connected to the input end of the low-noise amplifier 24.

[0087] Switch circuit 51A is an example of a first switch circuit, and is connected between antenna connection terminals 101 and 102 and filters 31 to 35. Switch circuit 51A includes common terminals 511 and 512 and selection terminals 513, 514, 515, and 516. Selection terminal 516 is an example of a seventh selection terminal, and is connected to filter 35.

[0088] In such a connection configuration, the switch circuit 51A can connect the common terminal 511 to at least the selection terminals 513 and 514, and can connect the common terminal 512 to at least the selection terminals 515 and 516, for example, based on a control signal from the RFIC 5.

[0089] [2.2. Multiple Communication Modes] Next, multiple communication modes of the high-frequency circuit 1A will be described.

[0090] [2.2.1. First Mode] First, the first mode included in the plurality of communication modes will be described with reference to Fig. 7. Fig. 7 is a diagram showing the first mode of the high-frequency circuit 1A according to this embodiment.

[0091] The first mode is a communication mode for transmitting a signal of band A and receiving MIMO signals of bands A and B. Switch circuit 51A connects common terminal 511 to selection terminals 513 and 514, and connects common terminal 512 to selection terminals 515 and 516. Switch circuit 52 connects common terminal 521 to selection terminal 523, and connects common terminal 522 to selection terminal 524.

[0092] As a result, the band A transmission signal is transmitted from the RFIC 5 to the antenna 4a via the radio frequency input terminal 111, the power amplifier 11, the filter 32, the switch circuit 51A, and the antenna connection terminal 101. One of the band A MIMO reception signals is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51A, the filter 31, the low noise amplifier 21, and the radio frequency output terminal 121. The other of the band A MIMO reception signals is transmitted from the antenna 4b to the RFIC 5 via the antenna connection terminal 102, the switch circuit 51A, the filter 35, the low noise amplifier 24, and the radio frequency output terminal 124. One of the band B MIMO reception signals is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51A, the filter 33, the switch circuit 52, the low noise amplifier 22, and the radio frequency output terminal 122. The other MIMO received signal of band B is transmitted from antenna 4 b to RFIC 5 via antenna connection terminal 102 , switch circuit 51 A, filter 34 , switch circuit 52 , low-noise amplifier 23 , and high-frequency output terminal 123 .

[0093] [2.2.2. Second Mode] Next, the second mode included in the plurality of communication modes will be described with reference to Fig. 8. Fig. 8 is a diagram showing the second mode of the high-frequency circuit 1A according to this embodiment.

[0094] The second mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 101 and the antenna 4a. The switch circuit 51A connects the common terminal 511 to the selection terminals 513 and 514. The switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0095] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51A, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4a via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 33, the switch circuit 51A, and the antenna connection terminal 101.

[0096] [2.2.3. Third Mode] Next, a third mode included in the plurality of communication modes will be described with reference to Fig. 9. Fig. 9 is a diagram showing the third mode of the high-frequency circuit 1A according to this embodiment.

[0097] The third mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 102 and the antenna 4b. The switch circuit 51A connects the common terminal 511 to the selection terminals 513 and 514, and connects the common terminal 512 to the selection terminal 515. The switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0098] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51A, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4b via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 34, the switch circuit 51A, and the antenna connection terminal 102.

[0099] In this way, in all of the first to third modes, the common terminal 511 of the switch circuit 51A is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, and can suppress deterioration of the reception characteristics of band A due to SRS transmission of band B (for example, a decrease in throughput).

[0100] The multiple communication modes of the high-frequency circuit 1A may include other modes in addition to the first to third modes. For example, the multiple communication modes of the high-frequency circuit 1A may include a fourth mode for receiving a signal in band A and supplying an SRS in band B to the high-frequency circuits 2 and / or 3. In the fourth mode, the switch circuit 51A may connect the common terminal 511 to the selection terminals 513 and 514, and the switch circuit 52 may connect the common terminal 526 to the selection terminal 525. Furthermore, for example, the multiple communication modes of the high-frequency circuit 1A may include a fifth mode for transmitting and receiving a signal in band B. In the fifth mode, the switch circuit 51A may connect the common terminal 511 to the selection terminal 514, but may not connect the common terminal 511 to the selection terminal 513, and the switch circuit 52 may switch the connection of the common terminal 521 between the selection terminals 523 and 525. The multiple communication modes of the high-frequency circuit 1A may include communication modes different from the fourth and fifth modes.

[0101] [2.3. Summary] As described above, in the high-frequency circuit 1A according to this embodiment, the switch circuit 51A further includes a selection terminal 516, and the high-frequency circuit 1A further includes the low-noise amplifier 24 and the filter 35 connected between the selection terminal 516 and the low-noise amplifier 24 and having a pass band that includes the reception band of band A, and in the first mode, the switch circuit 51A further connects the common terminal 512 to the selection terminal 516.

[0102] According to this, by using the first mode, the high-frequency circuit 1A can support interband CA of bands A and B and MIMO of bands A and B. Furthermore, by using the second and third modes, the high-frequency circuit 1A can transmit SRS from each antenna while receiving a band A signal. At this time, in all of the first to third modes, the common terminal 511 of the switch circuit 51A is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained within the switch circuit 51A. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, thereby suppressing deterioration of the reception characteristics of band A (e.g., a decrease in throughput) due to SRS transmission of band B. Furthermore, the filter 34 is used both for receiving MIMO signals of band B and for transmitting SRS of band B. Therefore, the high-frequency circuit 1A can reduce the number of filters compared to when a filter for receiving MIMO signals of band B and a filter for transmitting SRS of band B are provided separately, thereby preventing the communication device 7A from becoming larger.

[0103] (Embodiment 3) Next, embodiment 3 will be described. In this embodiment, the main difference is that the high-frequency circuit is connected to three antennas. The following describes this embodiment with reference to the drawings, focusing on the differences from embodiment 2.

[0104] A communication device 7B according to this embodiment is similar to the first embodiment except that it includes a high-frequency circuit 1B instead of the high-frequency circuit 1, and therefore illustration and description of its basic configuration will be omitted.

[0105] [3.1. Circuit Configuration of High-Frequency Circuit 1B] An exemplary circuit configuration of a high-frequency circuit 1B according to this embodiment will be described with reference to Fig. 10. Fig. 10 is a circuit configuration diagram of a portion of a communication device 7B according to this embodiment. Specifically, Fig. 10 is a circuit configuration diagram of a main module of a communication device 7B according to this embodiment.

[0106] 10 is an exemplary circuit diagram, and the high-frequency circuit 1B can be implemented using any of a wide variety of circuit implementations and circuit technologies. Therefore, the description of the high-frequency circuit 1B provided below should not be construed as limiting.

[0107] The high-frequency circuit 1B includes power amplifiers 11 and 12, low-noise amplifiers 21, 22, 23 and 24, filters 31, 32, 33, 34 and 35, switch circuits 51B and 52, antenna connection terminals 101, 102 and 103, high-frequency input terminals 111 and 112, high-frequency output terminals 121, 122, 123 and 124, and an SRS output terminal 131.

[0108] The antenna connection terminal 103 is an example of a third antenna connection terminal and is an external connection terminal of the high-frequency circuit 1B. The antenna connection terminal 103 is connected to the antenna 4c outside the high-frequency circuit 1B, and is connected to the switch circuit 51B inside the high-frequency circuit 1B.

[0109] Switch circuit 51B is an example of a first switch circuit, and is connected between antenna connection terminals 101 to 103 and filters 31 to 35. Switch circuit 51B includes common terminals 511, 512, and 517, and selection terminals 513, 514, 515, and 516. Common terminal 517 is an example of a fifth common terminal, and is connected to antenna connection terminal 103.

[0110] In such a connection configuration, the switch circuit 51B can connect the common terminal 511 to at least the selection terminals 513 and 514, can connect the common terminal 512 to at least the selection terminals 515 and 516, and can connect the common terminal 517 to at least the selection terminals 515 and 516, for example, based on a control signal from the RFIC 5.

[0111] [3.2. Multiple Communication Modes] Next, multiple communication modes of the high-frequency circuit 1B will be described.

[0112] [3.2.1. First Mode] First, the first mode included in the plurality of communication modes will be described with reference to Fig. 11. Fig. 11 is a diagram showing the first mode of the high-frequency circuit 1B according to this embodiment.

[0113] The first mode is a communication mode for transmitting a signal of band A and receiving MIMO signals of bands A and B. Switch circuit 51B connects common terminal 511 to selection terminals 513 and 514, connects common terminal 512 to selection terminal 515, and connects common terminal 517 to selection terminal 516. Switch circuit 52 connects common terminal 521 to selection terminal 523, and connects common terminal 522 to selection terminal 524.

[0114] As a result, the band A transmission signal is transmitted from the RFIC 5 to the antenna 4a via the radio frequency input terminal 111, the power amplifier 11, the filter 32, the switch circuit 51B, and the antenna connection terminal 101. One of the band A MIMO reception signals is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51B, the filter 31, the low noise amplifier 21, and the radio frequency output terminal 121. The other of the band A MIMO reception signals is transmitted from the antenna 4c to the RFIC 5 via the antenna connection terminal 103, the switch circuit 51B, the filter 35, the low noise amplifier 24, and the radio frequency output terminal 124. One of the band B MIMO reception signals is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51B, the filter 33, the switch circuit 52, the low noise amplifier 22, and the radio frequency output terminal 122. The other MIMO reception signal of band B is transmitted from antenna 4 b to RFIC 5 via antenna connection terminal 102 , switch circuit 51 B, filter 34 , switch circuit 52 , low-noise amplifier 23 , and high-frequency output terminal 123 .

[0115] [3.2.2. Second Mode] Next, the second mode included in the plurality of communication modes will be described with reference to Fig. 12. Fig. 12 is a diagram showing the second mode of the high-frequency circuit 1B according to this embodiment.

[0116] The second mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 101 and the antenna 4a. The switch circuit 51B connects the common terminal 511 to the selection terminals 513 and 514, and the switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0117] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51B, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4a via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 33, the switch circuit 51B, and the antenna connection terminal 101.

[0118] [3.2.3. Third Mode] Next, a third mode included in the plurality of communication modes will be described with reference to Fig. 13. Fig. 13 is a diagram showing the third mode of the high-frequency circuit 1B according to this embodiment.

[0119] The third mode is a communication mode for receiving a signal of band A and transmitting an SRS of band B via the antenna connection terminal 102 and the antenna 4b. The switch circuit 51B connects the common terminal 511 to the selection terminals 513 and 514, and connects the common terminal 512 to the selection terminal 515. The switch circuit 52 connects the common terminal 521 to the selection terminal 525.

[0120] As a result, the received signal of band A is transmitted from the antenna 4a to the RFIC 5 via the antenna connection terminal 101, the switch circuit 51B, the filter 31, the low-noise amplifier 21, and the radio-frequency output terminal 121. The SRS of band B is transmitted from the RFIC 5 to the antenna 4b via the radio-frequency input terminal 112, the power amplifier 12, the switch circuit 52, the filter 34, the switch circuit 51B, and the antenna connection terminal 102.

[0121] In this way, in all of the first to third modes, the common terminal 511 of the switch circuit 51B is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, and can suppress deterioration of the reception characteristics of band A due to SRS transmission of band B (for example, a decrease in throughput).

[0122] The multiple communication modes of the high-frequency circuit 1B may include other modes in addition to the first to third modes. For example, the multiple communication modes of the high-frequency circuit 1B may include a fourth mode for receiving a signal in band A and supplying an SRS in band B to the high-frequency circuits 2 and / or 3. In the fourth mode, the switch circuit 51B may connect the common terminal 511 to the selection terminals 513 and 514, and the switch circuit 52 may connect the common terminal 526 to the selection terminal 525. Furthermore, for example, the multiple communication modes of the high-frequency circuit 1B may include a fifth mode for transmitting and receiving a signal in band B. In the fifth mode, the switch circuit 51B may connect the common terminal 511 to the selection terminal 514, but may not connect the common terminal 511 to the selection terminal 513, and the switch circuit 52 may switch the connection of the common terminal 521 between the selection terminals 523 and 525. The multiple communication modes of the high-frequency circuit 1B may include communication modes different from the fourth and fifth modes.

[0123] [3.3. Summary] As described above, the high-frequency circuit 1B according to this embodiment further includes the low-noise amplifier 24 and the antenna connection terminal 103, the switch circuit 51B further includes the common terminal 517 and the selection terminal 516 connected to the antenna connection terminal 103, the high-frequency circuit 1B further includes the filter 35 connected between the selection terminal 516 and the low-noise amplifier 24 and having a passband that includes the reception band of band A, and in the first mode, the switch circuit 51B further connects the common terminal 517 to the selection terminal 516.

[0124] According to this, by using the first mode, the high-frequency circuit 1B can support interband CA of bands A and B and MIMO of bands A and B. Furthermore, by using the second and third modes, the high-frequency circuit 1B can transmit SRS from each antenna while receiving a band A signal. At this time, in all of the first to third modes, the common terminal 511 of the switch circuit 51B is connected to the selection terminals 513 and 514. That is, in the first to third modes, the connection between the common terminal 511 and the selection terminals 513 and 514 is maintained within the switch circuit 51B. This suppresses changes in impedance when viewing the filters 31 and 32 from the common terminal 511 in the first to third modes, thereby suppressing deterioration of the reception characteristics of band A (e.g., a decrease in throughput) due to SRS transmission of band B. Furthermore, the filter 34 is used both for receiving MIMO signals of band B and for transmitting SRS of band B. Therefore, the high-frequency circuit 1B can reduce the number of filters compared to when a filter for receiving a MIMO signal of band B and a filter for transmitting an SRS of band B are provided separately, thereby preventing the communication device 7B from becoming larger.

[0125] (Fourth Embodiment) Next, a fourth embodiment will be described. The high-frequency circuit according to this embodiment differs from the second embodiment mainly in that it includes more filters, switch circuits, low-noise amplifiers, etc. in order to support more bands. The following describes this embodiment, focusing on the differences from the second embodiment, with reference to FIG. 14 .

[0126] 14 is a circuit diagram of a high-frequency circuit 1C according to this embodiment. In FIG. 14, the numbers marked with B next to the filters represent numbers that identify frequency bands for LTE and / or 5G NR. For example, "B1" represents Band1 for LTE and / or n1 for 5G NR. Note that the frequency bands shown in FIG. 14 are examples to facilitate understanding by those skilled in the art, and the frequency bands corresponding to each filter are not limited to those shown in FIG. 14.

[0127] The high-frequency circuit 1C includes a plurality of power amplifiers including power amplifiers 11 and 12, a plurality of low-noise amplifiers including low-noise amplifiers 21 to 25, a plurality of filters including filters 31 to 35, a plurality of switch circuits including switch circuits 51C and 52C, antenna connection terminals 101 and 102, high-frequency input terminals 111 and 112, and a plurality of high-frequency output terminals including high-frequency output terminals 121 to 125.

[0128] The plurality of filters includes filters for B1, B3, B7, B25, B34, B39, B40, B41, B66 and B70.

[0129] In this embodiment, filters 31 and 35 are bandpass filters having a passband that includes the receive band of B3. Filter 32 is a bandpass filter having a passband that includes the transmit band of B3. Filters 33 and 34 are bandpass filters having passbands that include the transmit and receive bands of B41. That is, in this embodiment, B3 is used as band A, and B41 is used as band B.

[0130] The switch circuit 51C corresponds to the switch circuit 51A according to the second embodiment, and can switch the connection of the antenna connection terminals 101 and 102 between a plurality of filters.

[0131] The switch circuit 52C corresponds to the switch circuit 52 according to the second embodiment, and can switch the connections of the filters 33 and 34 between the power amplifier 12 and the low-noise amplifiers 22 and 23.

[0132] This high-frequency circuit 1C can transmit and receive high-frequency signals in a plurality of communication modes, similar to the second embodiment.

[0133] (Other Embodiments) While the high-frequency circuit and communication device according to the present invention have been described above based on the embodiments, the high-frequency circuit and communication device according to the present invention are not limited to the above embodiments. The present invention also includes other embodiments realized by combining any of the components in the above embodiments, modifications obtained by applying various modifications to the above embodiments that would occur to those skilled in the art without departing from the spirit of the present invention, and various devices incorporating the above-mentioned high-frequency circuit and communication device.

[0134] For example, in the circuit configurations of the high-frequency circuits and communication devices according to the above-described embodiments, other circuit elements and wiring may be inserted between the paths connecting the circuit elements and signal paths disclosed in the drawings. For example, an impedance matching circuit and / or a directional coupler may be connected between the antenna connection terminal 101 and the common terminal 511 and / or between the antenna connection terminal 102 and the common terminal 512. Furthermore, for example, an impedance matching circuit may be connected between the switch circuit 51, 51A, 51B, or 51C and the filters 31 to 35.

[0135] The following describes the features of the high-frequency circuit and communication device described based on the above embodiments.

[0136] <1> A first power amplifier and a second power amplifier; a first low-noise amplifier, a second low-noise amplifier, and a third low-noise amplifier; a first antenna connection terminal and a second antenna connection terminal; a first switch circuit including a first common terminal connected to the first antenna connection terminal, a second common terminal connected to the second antenna connection terminal, and a first selection terminal, a second selection terminal, and a third selection terminal; a second switch circuit including a third common terminal and a fourth common terminal, a fourth selection terminal connected to the second low-noise amplifier, a fifth selection terminal connected to the third low-noise amplifier, and a sixth selection terminal connected to the second power amplifier; a first filter connected between the first selection terminal and the first low-noise amplifier and having a passband including a receive band of a frequency division duplex (FDD) band; a second filter connected between the first selection terminal and the first power amplifier and having a passband including a transmit band of the FDD band; and a fourth filter connected between the third selection terminal and the fourth common terminal and having a passband including the TDD band, wherein in a first mode for transmitting and receiving signals in the FDD band and receiving MIMO (Multiple-Input and Multiple-Output) signals in the TDD band, the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal, and connects the second common terminal to the third selection terminal, and the second switch circuit connects the third common terminal to the fourth selection terminal, and connects the fourth common terminal to the fifth selection terminal; and in a second mode for receiving signals in the FDD band and transmitting a Sounding Reference Signal (SRS) of the TDD band via the first antenna connection terminal, the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal, and the second switch circuit connects the third common terminal to the sixth selection terminal,a third mode for receiving a signal in the FDD band and transmitting an SRS in the TDD band via the second antenna connection terminal, wherein the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal and connects the second common terminal to the third selection terminal, and the second switch circuit connects the fourth common terminal to the sixth selection terminal.

[0137] <2> The high-frequency circuit according to <1>, wherein the third filter and the fourth filter are each an acoustic wave filter, and the size of the third filter is larger than the size of the fourth filter.

[0138] <3> The high-frequency circuit according to <1> or <2>, wherein an attenuation amount of the third filter in the reception band of the FDD band is greater than an attenuation amount of the fourth filter in the reception band of the FDD band.

[0139] <4> The radio frequency circuit according to any one of <1> to <3>, wherein the first switch circuit further includes a seventh selection terminal, and the radio frequency circuit further includes: a fourth low-noise amplifier; and a fifth filter connected between the seventh selection terminal and the fourth low-noise amplifier and having a pass band including the reception band of the FDD band, and wherein in the first mode, the first switch circuit further connects the second common terminal to the seventh selection terminal.

[0140] <5> The high-frequency circuit according to any one of <1> to <3>, wherein the high-frequency circuit further includes: a fourth low-noise amplifier; and a third antenna connecting terminal; the first switch circuit further includes a fifth common terminal and a seventh selection terminal connected to the third antenna connecting terminal; the high-frequency circuit further includes: a fifth filter connected between the seventh selection terminal and the fourth low-noise amplifier and having a pass band including the reception band of the FDD band; and in the first mode, the first switch circuit further connects the fifth common terminal to the seventh selection terminal.

[0141] <6> The radio frequency circuit according to any one of <1> to <5>, wherein the FDD band is Band 1, Band 3, Band 25, or Band 66 for LTE, or n1, n3, n25, or n66 for 5G NR, and the TDD band is Band 40 or Band 41 for LTE, or n40 or n41 for 5G NR.

[0142] <7> A communication device comprising: a signal processing circuit configured to process a high-frequency signal; and the high-frequency circuit according to any one of <1> to <6> configured to transmit the high-frequency signal between the signal processing circuit and a first antenna and a second antenna, wherein the first antenna connection terminal is connected to the first antenna, and the second antenna connection terminal is connected to the second antenna.

[0143] The present invention can be widely used as a high-frequency circuit disposed in the front end of communication devices such as mobile phones.

[0144] 1, 1A, 1B, 1C, 2, 3 High frequency circuit 4a, 4b, 4c, 4d Antenna 5 RFIC 6 BBIC 7, 7A, 7B Communication device 11, 12 Power amplifier 21, 22, 23, 24, 25 Low noise amplifier 31, 32, 33, 34, 35 Filter 51, 51A, 51B, 51C, 52, 52C Switch circuit 101, 102, 103 Antenna connection terminal 111, 112 High frequency input terminal 121, 122, 123, 124 High frequency output terminal 131 SRS output terminal 511, 512, 517, 521, 522, 526 Common terminal 513, 514, 515, 516, 523, 524, 525 Selection terminal

Claims

1. A first power amplifier and a second power amplifier; a first low-noise amplifier, a second low-noise amplifier, and a third low-noise amplifier; a first antenna connection terminal and a second antenna connection terminal; a first switch circuit including a first common terminal connected to the first antenna connection terminal, a second common terminal connected to the second antenna connection terminal, and a first selection terminal, a second selection terminal, and a third selection terminal; a second switch circuit including a third common terminal and a fourth common terminal, a fourth selection terminal connected to the second low-noise amplifier, a fifth selection terminal connected to the third low-noise amplifier, and a sixth selection terminal connected to the second power amplifier; a first filter connected between the first selection terminal and the first low-noise amplifier and having a passband including a receive band of a frequency division duplex (FDD) band; a second filter connected between the first selection terminal and the first power amplifier and having a passband including a transmit band of the FDD band; and a fourth filter connected between the third selection terminal and the fourth common terminal and having a passband including the TDD band, wherein in a first mode for transmitting and receiving signals in the FDD band and receiving MIMO (Multiple-Input and Multiple-Output) signals in the TDD band, the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal, and connects the second common terminal to the third selection terminal, and the second switch circuit connects the third common terminal to the fourth selection terminal, and connects the fourth common terminal to the fifth selection terminal; and in a second mode for receiving signals in the FDD band and transmitting a Sounding Reference Signal (SRS) of the TDD band via the first antenna connection terminal, the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal, and the second switch circuit connects the third common terminal to the sixth selection terminal,a third mode for receiving a signal in the FDD band and transmitting an SRS in the TDD band via the second antenna connection terminal, wherein the first switch circuit connects the first common terminal to the first selection terminal and the second selection terminal and connects the second common terminal to the third selection terminal, and the second switch circuit connects the fourth common terminal to the sixth selection terminal.

2. The high-frequency circuit according to claim 1, wherein each of the third filter and the fourth filter is an acoustic wave filter, and the size of the third filter is larger than the size of the fourth filter.

3. The high-frequency circuit according to claim 1 or 2, wherein the attenuation of the third filter in the reception band of the FDD band is greater than the attenuation of the fourth filter in the reception band of the FDD band.

4. The radio frequency circuit according to any one of claims 1 to 3, wherein the first switch circuit further includes a seventh selection terminal, the radio frequency circuit further comprises: a fourth low noise amplifier; and a fifth filter connected between the seventh selection terminal and the fourth low noise amplifier and having a pass band including the reception band of the FDD band, and in the first mode, the first switch circuit further connects the second common terminal to the seventh selection terminal.

5. The radio frequency circuit according to any one of claims 1 to 3, wherein the radio frequency circuit further comprises: a fourth low noise amplifier; and a third antenna connection terminal; the first switch circuit further comprises a fifth common terminal and a seventh selection terminal connected to the third antenna connection terminal; the radio frequency circuit further comprises: a fifth filter connected between the seventh selection terminal and the fourth low noise amplifier and having a pass band including the reception band of the FDD band; and in the first mode, the first switch circuit further connects the fifth common terminal to the seventh selection terminal.

6. The radio frequency circuit according to any one of claims 1 to 5, wherein the FDD band is Band 1, Band 3, Band 25 or Band 66 for LTE, or n1, n3, n25 or n66 for 5G NR, and the TDD band is Band 40 or Band 41 for LTE, or n40 or n41 for 5G NR.

7. A communication device comprising: a signal processing circuit configured to process high-frequency signals; and a high-frequency circuit according to any one of claims 1 to 6 configured to transmit the high-frequency signals between said signal processing circuit and a first antenna and a second antenna, wherein said first antenna connection terminal is connected to said first antenna, and said second antenna connection terminal is connected to said second antenna.

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