According to various embodiment, an electronic device may include at least one communication processor, an RFIC, a power amplifier, and at least one modulator configured to provide the power amplifier with a supply voltage set for a first unit of time in a first mode or in a second unit of time shorter than the first unit of time in a second mode. The at least one communication processor may be configured to control the at least one modulator to provide the supply voltage according to the second mode and to switch from the second mode to the first mode when a variation in a voltage associated with a first element for providing the supply voltage is greater than or equal to a threshold magnitude while the supply voltage is provided to the power amplifier according to the second mode. Other various embodiments are possible as well.

Techniques for wireless communications are described. A communication device may support processing digital post distortion using additional references symbols. For example, the communication device may precode a signal including at least two reference symbols for a single-layer transmission using at least two antenna ports. At least one reference symbol of the at least two reference symbols is associated with at least one data symbol of a data stream. The communication device may estimate, based on the at least two reference symbols, a nonlinearity model of at least two power amplifiers associated with the single-layer transmission, and determine an estimate of a nonlinearity factor of the precoded signal based on the estimated nonlinearity model. As a result, the communication device may eliminate or reduce the nonlinear factor of the precoded signal based on the estimated nonlinearity model of the at least two power amplifiers and the estimated channel impulse response.

A radio frequency circuit includes: a first power amplifier capable of amplifying a first radio frequency signal and a second radio frequency signal each having a different frequency; and a second power amplifier capable of amplifying the second radio frequency signal. In a case where the first radio frequency signal and the second radio frequency signal are simultaneously transmitted, (i) under a condition that a sum of a bandwidth of the first radio frequency signal and a bandwidth of the second radio frequency signal is broader than or equal to a predetermined bandwidth, the first radio frequency signal is amplified by the first power amplifier, and the second radio frequency signal is amplified by the second power amplifier, and (ii) under a condition that the sum is narrower than the predetermined bandwidth, the first radio frequency signal and the second radio frequency signal are amplified by the first power amplifier.

A radio frequency module includes: a module board including first and second principal surfaces; first and second power amplifiers on the first principal surface; external-connection terminals on the second principal surface; and first and second via conductors connecting the first and second principal surfaces. The first and second via conductors are spaced apart in the module board, one end of the first via conductor is connected to a first ground electrode of the first power amplifier, the other end of the first via conductor is connected to a first external-connection terminal, one end of the second via conductor is connected to a second ground electrode of the second power amplifier, the other end of the second via conductor is connected to a second external-connection terminal, and the first and second via conductors each penetrate through the module board in a direction normal to the first and second principal surfaces.

A radio frequency circuit includes an amplifier capable of amplifying a first radio frequency signal and a second radio frequency signal that has a frequency different from a frequency of the first radio frequency signal. Here, the amplifier uses a first power-supply voltage to amplify one of the first radio frequency signal and the second radio frequency signal and uses a second power-supply voltage to amplify both the first radio frequency signal and the second radio frequency signal together. A value of the second power-supply voltage is greater than a value of the first power-supply voltage.

Apparatuses and methods are disclosed regarding a multiband transmitter. In an example aspect, an apparatus for processing signals for wireless transmission includes a wireless interface device. The wireless interface device includes an upconverter, a tunable filter, and a driver amplifier. The upconverter has an output and is configured to upconvert a baseband frequency to a radio frequency based on a local oscillator signal. The tunable filter has an input and an output; the input of the tunable filter is coupled to the output of the upconverter. The driver amplifier has an input; the input of the driver amplifier is coupled to the output of the tunable filter.

A radio-frequency module includes an integrated circuit (IC) device and an external inductor provided outside the IC device. The IC device includes a plurality of low-noise amplifiers, one or more inductors, and a switching circuit. The plurality of low-noise amplifiers includes a plurality of transistors in one to one correspondence. The one or more inductors are coupled to one or more of the plurality of transistors. Each inductor is coupled to the emitter or source of a corresponding one of the plurality of transistors. The switching circuit is coupled between the emitter or source of each of the plurality of transistors and the external inductor. The external inductor is coupled between the switching circuit and ground in series with each of the one or more inductors via the switching circuit.

According to one aspect, an integrated circuit having a radio frequency amplifier includes at least two amplifier stages and an impedance matching device between two amplifier stages of the radio frequency amplifier. The matching device includes two lines which are coupled by electromagnetic induction. The first line is connected to an output of the first amplifier stage and the second line is connected to an input of the second amplifier stage.

The present disclosure relates to an electronic device comprising a first capacitor and a quartz crystal coupled in series between a first node and a second node; an inverter coupled between the first and second nodes; a first variable capacitor coupled between the first node and a third node; and a second variable capacitor coupled between the second node and the third node.

A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying circuit element; a second amplifying circuit element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying circuit element. Another end of the primary coil is connected to an output terminal of the second amplifying circuit element. An end of the secondary coil is connected to an output terminal of the power amplifier. The first amplifying circuit element and the second amplifying circuit element are disposed on the first principal surface. The first circuit component is disposed on the second principal surface.