Abstract: A radio frequency circuit is capable of simultaneously transmitting a signal of a band A and a signal of a band B, a second downlink operation band of the band B overlapping (2×f2?f1), where f1 is a frequency of a first uplink operation band of the band A, and f2 is a frequency of a second uplink operation band of the band B, the radio frequency circuit including antenna connection terminals connected to different antennas, a filter that is connected to the antenna connection terminal and has a pass band that includes the first uplink operation band, a filter that is connected to the antenna connection terminal and has a pass band that includes the second uplink operation band, and a filter that is connected to the antenna connection terminal and has a pass band that includes a second downlink operation band.

Abstract: A front-end module includes: a first front-end circuit that transmits signals in a first band in a CA mode; and a second front-end circuit that transmits signals in a second band in the CA mode. The second front-end circuit includes a second quadplexer for the first and second bands. The first front-end circuit includes: a first quadplexer for the first and second bands; and an impedance variable circuit that is connected to a transmission terminal that is included in the first quadplexer and corresponds to the second band. In the CA mode, the impedance variable circuit serves as a reflection circuit that causes reflection of transmission waves in the second band. In a non-CA mode, the impedance variable circuit serves as a matching circuit that transmits or absorbs transmission waves in the second band.

Abstract: An electronic component includes a multilayer body including dielectric layers, a circuit pattern, and band-shaped conductor patterns. The circuit pattern includes a conductor pattern that is disposed inside the multilayer body and defines an inductor. The band-shaped conductor patterns are grounded and cover a portion of a shield surface. An internal surface is located between the circuit pattern and an upper surface. On a shield surface, a non-shielded area is provided which is not covered with any of the band-shaped conductor patterns, and through which magnetic flux generated from the inductor is able to pass.

Abstract: A high-frequency front-end circuit includes a diplexer, a duplexer, and a low-band-side multiple reflection prevention unit. The diplexer includes an antenna connection terminal, a low-band-side terminal, and a high-band-side terminal, and separates a low-band communication signal and a high-band communication signal. The duplexer separates a transmission signal and a reception signal of the low-band communication signal. The multiple reflection prevention unit is disposed between the low-band-side terminal and the duplexer and reduces or prevents multiple reflections of a leakage signal of the high-band communication signal which leaks to the low band side.

Abstract: A front-end module that uses a carrier aggregation scheme in which Band, which is selected from a low-frequency band group, and Band, which is selected from a high-frequency band group, are used simultaneously for communication includes a plurality of signal paths that connect a power amplifier module to an antenna element, and an antenna switch module that switches connection between the antenna element and the plurality of signal paths. Harmonics of Band have frequencies that are included in Band. The front-end module further includes a switch element disposed in a TDD transmission path.

Abstract: A model generation system is a system for supporting the design of a transmitter circuit including a power amplifier. The model generation system includes an acquisition unit and a model generation unit. The acquisition unit acquires amplification performance data relating to performance of the transmitter circuit. The model generation unit generates an inference model on the basis of input data and output data using machine learning in which at least the amplification performance data is the input data and a characteristic value of the transmitter circuit is the output data.

Abstract: A front-end module includes: a first front-end circuit that transmits signals in a first band in a CA mode; and a second front-end circuit that transmits signals in a second band in the CA mode. The second front-end circuit includes a second quadplexer for the first and second bands. The first front-end circuit includes: a first quadplexer for the first and second bands; and an impedance variable circuit that is connected to a transmission terminal that is included in the first quadplexer and corresponds to the second band. In the CA mode, the impedance variable circuit serves as a reflection circuit that causes reflection of transmission waves in the second band. In a non-CA mode, the impedance variable circuit serves as a matching circuit that transmits or absorbs transmission waves in the second band.

Abstract: A high-frequency front-end circuit includes a diplexer, a duplexer, and a low-band-side multiple reflection prevention unit. The diplexer includes an antenna connection terminal, a low-band-side terminal, and a high-band-side terminal, and separates a low-band communication signal and a high-band communication signal. The duplexer separates a transmission signal and a reception signal of the low-band communication signal. The multiple reflection prevention unit is disposed between the low-band-side terminal and the duplexer and reduces or prevents multiple reflections of a leakage signal of the high-band communication signal which leaks to the low band side.

Abstract: An electronic component includes a multilayer body including dielectric layers, a circuit pattern, and band-shaped conductor patterns. The circuit pattern includes a conductor pattern that is disposed inside the multilayer body and defines an inductor. The band-shaped conductor patterns are grounded and cover a portion of a shield surface. An internal surface is located between the circuit pattern and an upper surface. On a shield surface, a non-shielded area is provided which is not covered with any of the band-shaped conductor patterns, and through which magnetic flux generated from the inductor is able to pass.

Abstract: A front-end module that uses a carrier aggregation scheme in which Band, which is selected from a low-frequency band group, and Band, which is selected from a high-frequency band group, are used simultaneously for communication includes a plurality of signal paths that connect a power amplifier module to an antenna element, and an antenna switch module that switches connection between the antenna element and the plurality of signal paths. Harmonics of Band have frequencies that are included in Band. The front-end module further includes a switch element disposed in a TDD transmission path.

Abstract: A built-in-circuit substrate includes a substrate body, an electrical circuit including inner electrodes provided inside the substrate body and to which an RF signal is input, outer electrodes which are provided on the substrate body so as to be connected to the electrical circuit and which each include an underlying metal layer and a nickel layer covering at least a portion of the underlying metal layer, and a permanent magnet which is arranged on the substrate body. Thus, noise caused by intermodulation distortion generated in the nickel layers of the outer electrodes is prevented.

Abstract: A built-in-circuit substrate includes a substrate body, an electrical circuit including inner electrodes provided inside the substrate body and to which an RF signal is input, outer electrodes which are provided on the substrate body so as to be connected to the electrical circuit and which each include an underlying metal layer and a nickel layer covering at least a portion of the underlying metal layer, and a permanent magnet which is arranged on the substrate body. Thus, noise caused by intermodulation distortion generated in the nickel layers of the outer electrodes is prevented.