A front-end module (FEM) is disclosed that includes an integrous signal combiner. The integrous signal combiner can process received signals and use a set of resonant circuits to filter signal noise prior to recombination of a plurality of signal bands that form an aggregate carrier signal. These resonant circuits may be placed after a set of low noise amplifiers and can be used to more efficiently reduce noise and parasitic loading within each of a set of signal paths. Each resonant circuit may be configured to filter noise relating to a bandwidth for a signal that is to be combined with the signal of the signal path that includes the resonant circuit. In some implementations, the integrous signal combiner can be a tunable integrous signal combiner with resonant circuits that may be reconfigurable or dynamically configurable.

Various embodiments relate to a method for calibration of a center frequency of a BPF in an FSK transceiver, the method including the steps of filtering a carrier frequency signal by the BPF to produce a filtered signal, detecting, by a phase-frequency detector (PFD), a difference in phase between the carrier frequency signal and the filtered signal from the BPF, sweeping a calibration code of the BPF, detecting a transition in the sign of the phase difference and capturing a calibration code associated with the transition in the sign of the phase difference for calibration of the BPF.

An antenna switch circuit and an antenna circuit switching method. The circuit includes an antenna port, a termination port (e.g., for disposal of power reflected back from an antenna and received through the antenna port in a transmit mode), and a receive port (e.g., for receiving a signal from the antenna port via the antenna switch circuit in a receive mode). The circuit also includes a first switch coupled between the antenna port and the termination port. The circuit further includes a resonant inductance coupled between the receive port and the node located between the antenna port and the first switch. The circuit also includes a second switch coupled between a reference potential and a node located between the resonant inductance and the receive port.

An apparatus comprises an input port, an output port, and a resonant receive switch circuit. The resonant receive switch circuit may be coupled between the input port and the output port. The resonant receive switch circuit may comprise a first switch, a second switch, and an input matching circuit. When the first and the second switches are in a non-conducting state, a signal at the input port is passed to the output port. When the first and the second switches are in a conducting state, the signal at the input port is prevented from reaching the output port.

A circuit arrangement for compensating for an attenuation occurring in an antenna signal link between a mobile radio terminal and an antenna has at least one antenna signal amplifier in the antenna signal link and a control unit for adjusting a gain factor. The antenna signal conducted through an associated antenna signal amplifier is amplified or attenuated. The circuit arrangement has a detection unit for detecting an antenna signal power (P.sub.M, P.sub.A) of the antenna signal in the signal path of the antenna signal link. The control unit is configured for changing the gain factor, detecting a change, changing the transmit power (P.sub.M) of the mobile radio terminal, and adapting the gain factor to the coupling attenuation of the antenna signal link in dependence on a detected response of the mobile radio terminal.

A front-end module (FEM) is disclosed that includes an integrous signal combiner. The integrous signal combiner can process received signals and use a set of resonant circuits to filter signal noise prior to recombination of a plurality of signal bands that form an aggregate carrier signal. These resonant circuits may be placed after a set of low noise amplifiers and can be used to more efficiently reduce noise and parasitic loading within each of a set of signal paths. Each resonant circuit may be configured to filter noise relating to a bandwidth for a signal that is to be combined with the signal of the signal path that includes the resonant circuit. In some implementations, the integrous signal combiner can be a tunable integrous signal combiner with resonant circuits that may be reconfigurable or dynamically configurable.

A radio frequency module includes a first receive circuit that processes a receive signal in the first frequency band. The first receive circuit includes a first substrate, a first low noise amplifier, and a first filter circuit. The first low noise amplifier is mounted on a principal surface of the first substrate. The first filter circuit is connected to an output end of the first low noise amplifier. At least a portion of the first filter circuit is provided on the principal surface of the first substrate. The first filter circuit attenuates spurious components occurring due to a transmit signal in the first frequency band received by the first low noise amplifier. The spurious components are included in the transmit signal in the first frequency band and have a frequency bandwidth that overlaps, includes, or is included in the frequency bandwidth of the receive signal in the second frequency band.

Filters include a housing having an input port and an output port and a plurality of resonant cavities within the housing. Each resonant cavity may include a respective notch resonator. The filter may further include a bandpass filter that includes a plurality of bandpass resonators, the bandpass filter extending between the input port and the output port. The bandpass filter may replace a transmission line that is included in conventional filters.

A radio frequency switch apparatus includes switching circuits connected between respective signal terminals and an antenna terminal. Each of the switching circuits includes a series switching circuit and a shunt switching circuit configured to switch a signal band on and off. An inductor circuit includes an inductor device connected between at least one shunt switching circuit of the switching circuits and a ground. The inductor device suppresses noise and passes the signal band by being resonant with a capacitance present upon the shunt switching circuit being turned off.

A circuit arrangement for compensating for an attenuation occurring in an antenna signal link between a mobile radio terminal and an antenna has at least one antenna signal amplifier in the antenna signal link and a control unit for adjusting a gain factor. The antenna signal conducted through an associated antenna signal amplifier is amplified or attenuated. The circuit arrangement has a detection unit for detecting an antenna signal power (P.sub.M, P.sub.A) of the antenna signal in the signal path of the antenna signal link. The control unit is configured for changing the gain factor, detecting a change, changing the transmit power (P.sub.M) of the mobile radio terminal, and adapting the gain factor to the coupling attenuation of the antenna signal link in dependence on a detected response of the mobile radio terminal.