Abstract: A variable phase shift circuit has a phase shifter including a first port and a second port; a through path including a first port and a second port; a first switch including a first common port and configured to select the first port of the phase shifter or the first port of the through path and to connect the first port or the first port to the first common port; and a second switch including a second common port and configured to select the second port of the phase shifter or the second port of the through path and to connect the second port or the second port to the second common port. Phase shift amounts between the first common port and the second common port are switched in accordance with selections made by the first switch and the second switch.

Abstract: Provided is a method for setting a communication channel for a base station employing carrier aggregation, which enables simultaneous use of radio waves at a plurality of frequency bands of different frequencies or a base station apparatus for setting a communication channel in accordance with carrier aggregation, which enables simultaneous transmission and reception at a plurality of frequency bands of different frequencies. At least one of a downlink frequency channel in a first frequency band and a downlink frequency channel in a second frequency band is set such that a frequency range of harmonics of an uplink frequency range in the first frequency band does not overlap a downlink frequency range in the second frequency band, the first frequency band and the second frequency band being included in the plurality of frequency bands for use in carrier aggregation.

Abstract: In an antenna device including a high-band antenna element and a low-band antenna element that are connected to a common feed point and feeding electric power using one feed point, influence by unnecessary resonance of the low-band antenna element in a high band is suppressed. The antenna device includes a high-band antenna element and a low-band antenna element that are connected to a common feed point, an antenna-shortening inductor that is connected to between the low-band antenna element and the feed point, and a capacitor that is connected to the antenna-shortening inductor in parallel.

Abstract: A front end circuit includes a circulator having a first port into which a transmission signal is input, a second port into/from which a transmission/reception signal is input/output, and a third port from which a reception signal is output. The impedance of the second port of the circulator is set to a value different from the impedance value of the first port and the third port. With his configuration, the narrowing of a frequency band and the increase in loss, which occur when an impedance matching circuit is additionally provided, are prevented.

Abstract: A variable phase shift circuit has a phase shifter including a first port and a second port; a through path including a first port and a second port; a first switch including a first common port and configured to select the first port of the phase shifter or the first port of the through path and to connect the first port or the first port to the first common port; and a second switch including a second common port and configured to select the second port of the phase shifter or the second port of the through path and to connect the second port or the second port to the second common port. Phase shift amounts between the first common port and the second common port are switched in accordance with selections made by the first switch and the second switch.

Abstract: There are provided an antenna, an antenna tuner configured to adjust frequency characteristics of the antenna, and a control circuit configured to change frequency characteristics of the antenna tuner in a boundary time set for a unit of time of communication. For example, after matching indicators based on VSWRs and received signal strength indicators based on RSSIs have been acquired in a plurality of times of communication space time, the antenna tuner is put into an optimum mode. This suppresses the decrease in communication throughput caused by the adjustment of the antenna tuner and suppresses the interruption of communication at the time of adjustment of the antenna tuner.

Abstract: The present disclosure includes a first circuit that is connected between a power feed port and an antenna port, and a second circuit that is connected between the power feed port and the ground or between the antenna port and the ground. The first circuit is a circuit in which for example a first variable capacitance element is connected in series with a first inductor, and the second circuit is a circuit in which for example a second variable capacitance element is connected in parallel with a second inductor. A switch performs switching at least between a first state in which a second end of the second circuit is connected to a first end of the first circuit and a second state in which the second end of the second circuit is connected to a second end of the first circuit.

Abstract: A front-end circuit includes a band switching unit (20) that is directly or indirectly connected to an antenna (10) and that switches connection to a frequency band used in transmission and reception, among multiple frequency bands, multiple demultiplexers (31 to 34) that perform demultiplexing into transmission signals and reception signals in the respective frequency bands, and antenna matching circuits (41 to 44). One of the antenna matching circuits (41 to 44) is disposed between at least one demultiplexer, among the multiple demultiplexers (31 to 34), and the band switching unit (20). For example, the antenna matching circuits (41 to 44) include reactance elements (L1, L2, C32, C42) that are connected in series to circuits connecting the band switching unit (20) to the demultiplexers (31 to 34) and reactance elements (C1, C2, C31, C41) that are connected in parallel thereto, respectively.

Abstract: A front end circuit includes a variable matching circuit connected to a diplexer and a switch connector connected between an antenna port and the diplexer. The variable matching circuit selectively connects matching circuits to a signal path. When one of the matching circuits is connected, the impedance as viewed from the switch connector matches an impedance of a measurement circuit near a normalized impedance of 1 in a predetermined communication band, whereas when the other matching circuit is connected, the impedance viewed from the antenna port conjugate-matches the impedance of an antenna circuit in a predetermined communication band.

Abstract: Transmission paths correspond to frequency bands, respectively, and transmission signals of the four bands are transmitted through the transmission paths. Reception paths correspond to the frequency bands, respectively, and reception signals of the four bands are transmitted through the reception bands. A Tx switch selects a transmission path corresponding to one of the frequency bands so that a transmission signal corresponding to the frequency band is emitted from an antenna. An Rx switch selects a reception path corresponding to the frequency band so that a reception signal of the frequency band received by the antenna is extracted. A tunable filter is a filter whose frequency band is adjusted in a variable manner so that reception band noise of the frequency band is attenuated, and is provided between each of the antenna and the Rx switch, and the Tx switch.

Abstract: Provided is a method for setting a communication channel for a base station employing carrier aggregation, which enables simultaneous use of radio waves at a plurality of frequency bands of different frequencies or a base station apparatus for setting a communication channel in accordance with carrier aggregation, which enables simultaneous transmission and reception at a plurality of frequency bands of different frequencies. At least one of a downlink frequency channel in a first frequency band and a downlink frequency channel in a second frequency band is set such that a frequency range of harmonics of an uplink frequency range in the first frequency band does not overlap a downlink frequency range in the second frequency band, the first frequency band and the second frequency band being included in the plurality of frequency bands for use in carrier aggregation.

Abstract: An antenna device includes a communication module and a loop-shaped conductor. The communication module has a substrate on which an approximately rectangular ground conductor is formed. A non-ground region is provided along one side of the ground conductor. A transmission line and a radiation element are formed in the non-ground region. Further, a capacitance element is connected to the radiation element, and the transmission line is connected to a feeding point of the radiation element. The loop-shaped conductor includes in part a gap that is positioned near the radiation element. With this, an antenna device to be provided in an electronic apparatus having wide directivity in a state of being attached to a garment, a person's body, or the like, and the stated electronic apparatus are configured.

Abstract: In an antenna device including a high-band antenna element and a low-band antenna element that are connected to a common feed point and feeding electric power using one feed point, influence by unnecessary resonance of the low-band antenna element in a high band is suppressed. The antenna device includes a high-band antenna element and a low-band antenna element that are connected to a common feed point, an antenna-shortening inductor that is connected to between the low-band antenna element and the feed point, and a capacitor that is connected to the antenna-shortening inductor in parallel.

Abstract: A substrate includes a dielectric plate and a conductive layer formed on both surfaces of the dielectric plate, and a first cutout is formed in the conductive layer on both surfaces of the substrate so as to extend inward from part of a first edge of the substrate. A first radiation electrode is connected to the conductive layer at a first point located on an outer peripheral line of the first cutout. A first reflector plate is disposed in a location further inward in the substrate from the first edge than the first point. The reflector plate is electrically connected to the conductive layer, and faces toward the first point. Thus an antenna device that is suited to miniaturization and that is capable of increasing directivity is provided.

Abstract: A front end circuit includes a circulator having a first port into which a transmission signal is input, a second port into/from which a transmission/reception signal is input/output, and a third port from which a reception signal is output. The impedance of the second port of the circulator is set to a value different from the impedance value of the first port and the third port. With his configuration, the narrowing of a frequency band and the increase in loss, which occur when an impedance matching circuit is additionally provided, are prevented.

Abstract: A variable resonant circuit is inserted between a feeding point of a radiating element and a ground conductor. When the variable resonant circuit is not inserted, an input impedance of the radiating element is lower than about 50? and capacitive in a first low frequency band, lower than about 50? and inductive in a second low frequency band, and close to about 50? in a high frequency band. When the variable resonant circuit exhibits a first resonance characteristic, the variable resonant circuit is inductive in the first low frequency band, and its impedance in the high frequency band is higher than that in the first low frequency band. When the variable resonant circuit exhibits a second resonance characteristic, the variable resonant circuit is capacitive in the second low frequency band, and its impedance in the high frequency band is higher than that in the second low frequency band.

Abstract: A first radiating element and a second radiating element each have a first extending portion protruding from a region where a ground conductor is formed to a non-ground-conductor region, and a second extending portion extending parallel with a boundary of the ground-conductor region and the non-ground-conductor region. The first radiating element and the second radiating element are arranged such that an open end of the second extending portion of the first radiating element and an open end of a second extending portion of the second radiating element face each other. A parasitic element is formed on a side of the second radiating element distant from the region (where the ground conductor is formed. A parasitic element is formed along the first radiating element. With this configuration, an antenna device is realized which has gain in two frequency bands and has forward directivity.

Abstract: A front end circuit and a wireless communication device capable of achieving matching with an antenna across a wide frequency band and capable of suppressing degradation in high-frequency characteristics caused by the influence of transmission signal harmonics is provided. A front end circuit includes a variable matching circuit connected to a low-frequency band transmission port side of a diplexer and a harmonic filter connected between the variable matching circuit and the diplexer. The harmonic filter has a pass band that overlaps with a low-frequency band-side communication band and a stop band that overlaps with a harmonic frequency of the low-frequency band-side communication band.

Abstract: A first housing includes a first conductor plate, and a second housing includes a second conductor plate. A rotation mechanism openably and closably attaches the second housing to the first housing. A first driven element and a second driven element are arranged along a rotation axis of the rotation mechanism. Between the first driven element and the second driven element, a continuity structure intersects the rotation axis to establish direct-current or high-frequency continuity between the first conductor plate and the second conductor plate. An antenna device can be provided which can ensure sufficient isolation between a plurality of driven elements.

Abstract: A front end circuit includes a variable matching circuit connected to a diplexer and a switch connector connected between an antenna port and the diplexer. The variable matching circuit selectively connects matching circuits to a signal path. When one of the matching circuits is connected, the impedance as viewed from the switch connector matches an impedance of a measurement circuit near a normalized impedance of 1 in a predetermined communication band, whereas when the other matching circuit is connected, the impedance viewed from the antenna port conjugate-matches the impedance of an antenna circuit in a predetermined communication band.