Murata Manufacturing Co., Ltd.

Syunji Yoshimi

Takeshi Kogure

Jin Yokoyama

Kenji Saito

Mizuho Ishikawa

Hidetaka Takahashi

Shiro Masumoto

Yuki Higashide

Masatoshi Hase

Kenichi Shimamoto

Yusuke Tanaka

Kenji Tahara

Shingo Yanagihara

Kazuhiro Ikarashi

The present disclosure facilitates impedance matching between a power amplifier and filters. A radio-frequency circuit includes a power amplifier, a plurality of transmit filters, a switch, a plurality of first matching networks, and a second matching network. The switch switches the plurality of transmit filters to be coupled to the power amplifier. The plurality of first matching networks are coupled between the plurality of transmit filters and the switch. The second matching network is coupled between the power amplifier and the switch. The second matching network includes a transmission line transformer.

Radio-frequency circuit and communication device

A high-frequency signal transmission-reception circuit includes a plurality of band pass filter groups each including a plurality of band pass filter pairs; a first switch including a plurality of band pass filter-side terminal groups each including a plurality of band pass filter-side terminals, and an antenna-side terminal group; a plurality of couplers configured to output respective signal strengths of high-frequency signals transmitted on a plurality of transmission paths; and a second switch including an input terminal group electrically connected to the plurality of couplers, and an output terminal configured to output a detection signal output from one of the plurality of couplers. The first switch electrically connects one band pass filter-side terminal in one band pass filter-side terminal group and one antenna-side terminal, and also electrically connects one band pass filter-side terminal in another band pass filter-side terminal group and another antenna-side terminal.

High-frequency signal transmission-reception circuit

A multi-band power amplifier module includes at least one transmission input terminal, at least one power amplifier circuit that receives a first transmission signal and a second transmission signal through the at least one transmission input terminal, a first filter circuit that allows the first transmission signal to pass therethrough, a second filter circuit that allows the second transmission signal to pass therethrough, at least one transmission output terminal through which the first and second transmission signals output from the first and second filter circuits are output, a transmission output switch that outputs each of the first and second transmission signals output from the at least one power amplifier circuit to the first filter circuit or the second filter circuit, and a first tuning circuit that adjusts impedance matching between the at least one power amplifier circuit and the at least one transmission output terminal.

Multi-band power amplifier module

A transmit-and-receive module includes a multiplexer, a power amplifier, and a low-noise amplifier. The multiplexer includes a transmit filter and a receive filter. The power amplifier and the low-noise amplifier are integrated with each other. In a Smith chart, impedance in a receive band of the receive filter seen from a receive terminal intersects a line connecting a center point of noise figure circles and a center point of gain circles. The center point of the noise figure circles represents the impedance at which the noise figure of the low-noise amplifier is minimized. The center point of the gain circles represents the impedance at which the gain of the low-noise amplifier is maximized.

Transmit-and-receive module and communication device

A high frequency module includes a duplexer that includes a transmission filter, a receive-only filter, and a power amplifier that power-amplifies a transmission signal. In order to improve the isolation characteristics between a transmission signal and a reception signal at the duplexer, the receive-only filter is arranged between the power amplifier and the duplexer.

High frequency module

A transmit-and-receive module includes a power amplifier, a low-noise amplifier, first and second phase shifter circuits, and a correction circuit. The power amplifier amplifies power of first and second transmit signals. The low-noise amplifier amplifies first and second received signals without increasing noise. The first and second phase shifter circuits adjust impedance for the first received signal and that for the second received signal. The correction circuit supplies a canceling signal to an output node of the second phase shifter circuit. The canceling signal is used for canceling the first transmit signal passing through a receive filter.

Transmit-and-receive module

Isolators are disposed such that DC magnetic fields of permanent magnets intensity with each other, and thus, the input impedance of non-reciprocal circuitsand(regulating means) is reduced. Accordingly, the impedance conversion ratio between the output impedance of amplifying meansand the input impedance of the regulating meansis reduced to be relatively small. Thus, by simplifying the configuration of matching meansdisposed between the amplifying meansand the regulating means, the insertion loss of the matching meanscan be reduced, thereby enhancing the efficiency of a circuit module. Additionally, it is possible to dispose the non-reciprocal circuitsandclose to each other so that the DC magnetic fields of the permanent magnets can intensity with each other, thereby increasing the design flexibility of the circuit moduleand accordingly reducing the size of the circuit module

Circuit module

As a capacitor Cj is connected in parallel to a non-reciprocal circuit, in a predetermined frequency band in which a power amplifieris used, or in other words, in a predetermined frequency band used in communication, an input impedance of the non-reciprocal circuitis adjusted and the length of an impedance curve (reflection coefficient S) at an input terminal Pof the non-reciprocal circuitcan thus be reduced. In addition, an output impedance of the power amplifierand an input impedance of the non-reciprocal circuitcan be matched in a broad band through an interstage matching circuit(input matching circuit) provided between an output terminal Pof the power amplifierand the input terminal Pof the non-reciprocal circuit

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Kyoto, Japan

Syunji Yoshimi