The disclosed device may include a radio frequency (RF) component and a thermal management component establishing a thermal path with the RF component. The device may also include an RF filter electrically that is coupled to the RF component and arranged away from the thermal path. The device may further include a chassis for housing the RF component. The thermal management component and the RF filter may be positioned near an exterior of the chassis. Various other devices, apparatuses, and systems are also disclosed.

A power amplifier comprises a first transistor, a first transformer, a first variable resistor, a first bias circuit and coupling circuitry configured to couple the first transformer, a first end of the first variable resistor, and a collector of the first transistor at a first node, the first transformer and a second end of the first variable resistor at a second node, and the bias circuit and a base of the first transistor at a third node.

An auxiliary control circuit (100) for a power amplification module, a power amplification module, and a communication device. The auxiliary control circuit (100) for the power amplification module comprises a main control chip (201), a current detection chip (12), and a precision adjustment unit (14). The precision adjustment unit (14) is connected in parallel to a precision control resistor of the current detection chip (12), and a switch control terminal of the precision adjustment unit (14) is electrically connected to the main control chip (201) and is used for adjusting an output voltage amplification factor of the current detection chip (12) when a switch signal outputted by the main control chip (201) is received. A detection input terminal of the current detection chip (12) is used for accessing a voltage to be measured of a power amplifier transistor power supply circuit (102) of the power amplification module. A detection output terminal of the current detection chip (12) is electrically connected to the main control chip (201). The main control chip (201) is used, upon receipt of a voltage signal outputted by the current detection chip (12), to measure and calculate so as to obtain a power amplification current corresponding to the voltage to be measured. By providing the precision adjustment unit (14) on the power amplification module for cooperation with the main control chip (201) and the current detection chip (12), the effect of greatly improving the detection precision of a power amplification current is achieved.

Certain aspects of the present disclosure provide techniques for determining a cable loss associated with a transmission cable of an apparatus. An example method includes sending, to a radio modem of the apparatus, a request for the radio modem to use a target power when sending one or more signals to the signal compensator device for determining a cable loss associated with a transmission cable communicatively coupling the radio modem with the signal compensator device, receiving, at a signal compensator device of the apparatus, the one or more signals from the radio modem sent using the target power, and determining the cable loss associated with the transmission cable based on the one or more signals.

Disclosed are a predistortion method and system, a device, and a non-transitory computer-readable storage medium. The predistortion method is applicable to a predistortion system which may include a predistortion multiplier, a complex neural network, and a radio frequency power amplifier output feedback circuit. The method may include: inputting a training complex vector to the predistortion system to obtain a complex scalar corresponding to the training complex vector, which is output by the predistortion system; training the predistortion system based on the training complex vector and the complex scalar until a generalization error vector magnitude and a generalization adjacent channel leakage ratio corresponding to the predistortion system meet set requirements; and inputting a service complex vector to the trained predistortion system to obtain a predistortion corrected complex scalar.

A compact directed energy system is disclosed that is configured to generate directed energy beams. The compact directed energy system includes a radio frequency system configured to provide a directed energy beam in a frequency range between 500 MHz to 20 Ghz.

A power amplifier circuit includes a power amplifier, first and second filters, and first and second output paths. The power amplifier is able to amplify both of a first signal and a second signal. The frequency of the second signal is higher than that of the first signal. The first filter includes a first inductor and attenuates the second signal amplified in the power amplifier. The first inductor serves as a path for the first signal amplified in the power amplifier. The second filter includes a first capacitor and attenuates the first signal amplified in the power amplifier. The first capacitor serves as a path for the second signal amplified in the power amplifier. The first signal outputted from the first filter is supplied to the first output path. The second signal outputted from the second filter is supplied to the second output path.

Methods and apparatus for limiting the input voltage (swing) of a power amplifier, such as a power amplifier in a radio frequency (RF) front-end of a wireless device. One example radio frequency front-end circuit generally includes a power amplifier, a matching circuit having an output coupled to an input of the power amplifier, and an overvoltage protection circuit coupled to the matching circuit. With an overvoltage protection circuit coupled to the matching circuit in this manner, the power amplifier may have enhanced ruggedness performance.

Aspects of this disclosure relate to acoustic wave devices on stacked die. A first die can include first acoustic wave device configured to generate a boundary acoustic wave. A second die can include a second acoustic wave device configured to generate a second boundary acoustic wave, in which the second die is stacked with the first die. The first acoustic wave resonator can include a piezoelectric layer, an interdigital transducer electrode on the piezoelectric layer, and high acoustic velocity layers on opposing sides of the piezoelectric layer. The high acoustic velocity layers can each have an acoustic velocity that is greater than a velocity of the boundary acoustic wave.

An apparatus is disclosed for controlling a power amplifier that is coupled to an antenna element of an antenna array. In example implementations, an apparatus includes an antenna element of an antenna array and a power amplification system. The power amplification system includes at least one input node, at least one output node coupled to the antenna element, and at least one power amplifier branch coupled between the at least one input node and the at least one output node. The power amplification system also includes at least one feedback node coupled to the at least one output node, at least one control node, and a feedback control loop coupled between the at least one feedback node and the at least one control node.