A switchable RF transmit/receive (TX/RX) multiplexer, which includes a group of RF TX bandpass filters, a group of RF TX switching elements, and a group of RF RX bandpass filters; is disclosed. The group of RF TX bandpass filters includes a first RF TX bandpass filter and a second RF TX bandpass filter, such that each of the first RF TX bandpass filter and the second RF TX bandpass filter is coupled to a first filter connection node. The group of RF TX switching elements includes a first RF TX switching element coupled between the first filter connection node and a first common connection node, which is coupled to a first RF antenna. Each of the group of RF RX bandpass filters is coupled to the first common connection node.

A front-end module, which uses a carrier aggregation method in which communication is performed by simultaneously using Band 8 and Band 3, includes an antenna switch module that switches connections between an antenna and a plurality of signal paths, a first circuit that is connected to a Band 8 signal path, and a second circuit that is connected to a Band 3 signal path and is electromagnetic-field coupled with the first circuit. A signal including a Band 3 frequency component that propagates from the signal path to the signal path via the antenna switch module and a signal including a Band 3 frequency component that propagates from the signal path to the signal path via the first circuit and the second circuit have a phase-shifted relationship with each other.

[Object] To propose a wireless communication apparatus capable of realizing separation of transmission signals and reception signals with a low power consumption and a small size. [Solution] Provided is a wireless communication apparatus including: a gyrator that includes at least four terminals; a single-phase differential converter that mutually converts single-phase signals and differential signals; a low-noise differential amplifier that amplifies reception signals that the gyrator outputs; and a differential power amplifier that amplifies transmission signals to be output to the gyrator. The gyrator transmits signals from a first terminal and a second terminal in the direction of a third terminal and a fourth terminal. Any of the single-phase differential converter, the low-noise amplifier, and the power amplifier are connected to the first terminal and second terminal, the third terminal and fourth terminal, the first terminal and third terminal, and the second terminal and fourth terminal of the gyrator.

A radio-frequency module includes duplexers and a phase circuit. A first transmitting-signal input terminal is connected to the duplexer, while a second transmitting-signal input terminal is connected to the duplexer. The phase circuit is connected between the first transmitting-signal input terminal and the duplexer. The phase circuit performs phase adjustment so that impedance matching between the first transmitting-signal input terminal and the duplexer is performed in the fundamental frequency band of a first transmitting signal, and so that the phase of the frequency band of a second transmitting signal in relation to the impedance characteristics of a first transmission path which ranges from the first transmitting-signal input terminal to the duplexer with the phase circuit provided therebetween appears in an open side on a Smith chart.

Techniques to implement a filter for a selected signal path by reusing a circuit component in an unselected signal path are disclosed. In an exemplary design, an apparatus includes first, second, and third circuits. The first circuit passes a first radio frequency (RF) signal to an antenna when a first signal path is selected. The second circuit passes a second RF signal to the antenna when a second signal path is selected. The third circuit is selectively coupled to the first circuit, e.g., via a switch. The first and third circuits form a filter for the second RF signal (e.g., to attenuate a harmonic of the second RF signal) when the second signal path is selected and the first signal path is unselected. The first circuit may include a series inductor, and the third circuit may include a shunt capacitor.

A resonator circuit, a filter with improved tunability, and a duplexer with improved tunability are disclosed. In an embodiment, the resonator circuit includes a resonator, a Z transformer and an impedance circuit, wherein the impedance circuit has an impedance Z and includes an impedance element, wherein the Z transformer is interconnected between the resonator and the impedance circuit, and wherein the Z transformer transforms the impedance Z to a new impedance ZZ and comprises a transformation circuit selected from: a generalized impedance converter (GIC), an negative impedance converter (NIC), a generalized impedance inverter (GII) and an negative impedance inverter (NII).

Disclosed are a duplexer, a network device, a control method, an electronic device and a storage medium. The duplexer may include: a filter, a dielectric tuning component; and a control module connected with the dielectric tuning component and configured to control a relative position between the dielectric tuning component and the filter to adjust an operating frequency of the duplexer.

A radar transceiver is provided. The radar transceiver includes an electrical balance duplexer that is coupled to a transmission node of a transmission path, a reception node of a reception path, and an antenna node and that is configured to isolate the transmission path from the reception path. The electrical balance duplexer includes a hybrid transformer network and a non-tunable balancing impedance. The non-tunable balancing impedance is configured to provide a fixed impedance value that corresponds to an impedance value at the antenna node.