Example signal processing methods and apparatus are described. The signal processing apparatus includes a first power amplifier, a second power amplifier, a first filter, a second filter, and a combiner. The first filter filters a second signal obtained by the first power amplifier to obtain a first sub-signal belonging to a first frequency band and a second sub-signal belonging to a second frequency band. The second filter filters a fourth signal obtained by the second power amplifier to obtain n sub-signals including at least a third sub-signal belonging to a third frequency band. The combiner combines the first sub-signal and i sub-signals in the n sub-signals based on a preset condition to obtain a first combined signal. The communication module sends the first combined signal by using a first port, and sends the second sub-signal by using a second port.

A radio-frequency module includes a switch performing switching of the connection between a common terminal and a selection terminal, a reception filter having a reception band in a band A as a passband, a transmission filter that has a transmission band in a band B as a passband and has an output terminal connected to the selection terminal, a filter that has the transmission band in a band B as an attenuation band and has an input terminal connected to the selection terminal, a reception path which connects the selection terminal and an input terminal of the reception filter and on which the filter is disposed, a bypass path which connects the selection terminal and the input terminal of the reception filter and on which no filter is disposed, and a transmission path which connects the selection terminal and a transmission terminal and on which the transmission filter is disposed.

The present invention provides an interference cancellation circuit, wherein the interference cancellation circuit includes a PAPR detection circuit, a control circuit and a filter. In the operations of the interference cancellation circuit, the PAPR detection circuit is configured to detect a PAPR of a signal in a spectrum in a real-time manner to generate a detection result. The control circuit is configured to generate a control signal according to the detection result. The filter is configured to determine a filtering frequency point of the filter according to the control signal, and to filter the signal to generate an output signal.

A front-end module includes: a substrate including a first connection member in which at least one first insulating layer and at least one first wiring layer are alternately stacked, a second connection member in which at least one second insulating layer and at least one second wiring layer are alternately stacked, and a core member disposed between the first and second connection members; a radio-frequency component mounted on a surface of the substrate and configured to amplify a main band of an input RF signal or filter bands outside the main band; an inductor disposed on a surface of the core member and electrically connected to the radio-frequency component; and a ground plane disposed on another surface of the core member. The core member includes a core insulating layer thicker than an insulating layer among at least one first insulating layer and the at least one second insulating layer.

A radio frequency (RF) switch circuit is provided. The switch includes a branch configured and arranged to transfer an RF signal coupled at an input node to an output node when a control signal is at a first logic value. A first transistor in the branch includes a first current electrode coupled at the input node and a second current electrode coupled to an intermediate node. The first transistor is formed in a first isolation well coupled to a bias voltage supply terminal. A second transistor in the branch includes a first current electrode coupled to the second current electrode of the first transistor at the intermediate node and a second current electrode coupled at the output node. The second transistor is formed in a second isolation well coupled to the bias voltage supply terminal. A third transistor includes a first current electrode coupled at the first intermediate node and a second current electrode coupled at a first supply terminal.

An RF transceiver includes an RF transmitter coupled to a broadcast antenna, an RF receiver coupled to a receiving antenna, and a communication channel to provide an RF reference signal from the transmitter to the receiver to assist in canceling a transmitter-induced interference signal at the receiver. A digital processor of the receiver is configured for adaptive filtering the RF reference signal in the frequency domain to estimate the spectrum of the interference signal, and estimating a spectrum of a remotely-transmitted signal based on the estimated interference spectrum and a spectrum of a received signal from the receiving antenna. The filtering includes estimating frequency-domain filter weights based, at least, on spectra of the received and reference signals, and de-noising of the estimated filter weights. The interference cancellation may be iteratively improved using a re-modulated feedback from a demodulator and/or a decoder in the signal processing chain of the receiver.

Techniques maintaining receiver reliability, including determining a present attenuation level for an attenuator, wherein the attenuation level is set by a gain controller, determining a relative reliability threshold based on the present attenuation level, receiving a radio frequency (RF) signal, determining a voltage level of the received RF signal, comparing the voltage level of the received RF signal to the relative reliability threshold to determine that a reliability condition exists, and overriding, in response to the determination that the reliability condition exists, the present attenuation level set by the gain controller with an override attenuation level based on the present attenuation level.

A transceiver assembly includes a radio frequency (RF) transceiver configured to transmit and receive signals, and a transceiver controller operatively coupled with the transceiver via a transmit path and a receive path. A power amplifier disposed along the transmit path is configured to amplify RF signals for transmission by the transceiver. A power detection line is configured to provide power control feedback to the transceiver controller indicating an amplitude of current flowing from the power amplifier to the transceiver. A directionally-specific protection element disposed along the power detection line is configured to allow the power control feedback to flow to the transceiver controller over the power detection line in a first direction, while preventing at least some electrical noise originating from the transceiver controller from flowing through the power detection line in a second direction, thereby preventing the electrical noise from entering the receive path.

In a radio frequency module, the first inductor is disposed on the first principal surface of the mounting board and located on the first reception path through which a first reception signal of a first frequency passes, on an input side of the first low noise amplifier. The second inductor is disposed on the first principal surface of the mounting board and located on the second reception path through which a second reception signal of a second frequency lower than the first frequency passes, on an input side of the second low noise amplifier. The radio frequency component is disposed between the first inductor and the second inductor. A distance between the first inductor and the shielding layer is greater than a distance between the second inductor and the shielding layer. The first inductor overlaps the first low noise amplifier in a thickness direction of the mounting board.

A radio frequency module includes: a module substrate; a first circuit component disposed on a first principal surface of the module substrate; and a second circuit component stacked on the first circuit component. Here, one of the first circuit component and the second circuit component includes a reception filter, the other of the first circuit component and the second circuit component includes a switch connected between an antenna connection terminal and the reception filter, and the second circuit component is connected to the first circuit component via a via electrode in the first circuit component or a side wiring on a side surface of the first circuit component.