Techniques are provided to more accurately determine reflected power, reflection coefficient, and/or voltage standing wave to permit prompt protection of components such as power amplifiers and notify communication system operators. This is accomplished by more accurately determining an amplitude and phase of an output reflected signal at an output port of a bidirectional coupler as a function of the following: an amplitude and a phase of a coupled forward signal coupled into a forward coupled port of the bidirectional coupler; an amplitude and a phase of a coupled reverse signal coupled into a reverse coupled port of the bidirectional coupler; an electrical transmission parameter from an input port of the bidirectional coupler to the forward coupled port; an electrical transmission parameter from the input port to the reverse coupled port; and an electrical transmission parameter from an output port of the bidirectional coupler to the reverse coupled port.

A system for transmitting and receiving radio signals is disclosed. The system includes a controller having a modem and a transmission amplifier module connected to the modem, an antenna unit arranged at a distance from the controller and having an antenna and a reception amplifier module connected to the antenna, and a high-frequency cable connecting the controller and the antenna unit.

Techniques are provided to more accurately determine reflected power, reflection coefficient, and/or voltage standing wave to permit prompt protection of components such as power amplifiers and notify communication system operators. This is accomplished by more accurately determining an amplitude and phase of an output reflected signal at an output port of a bidirectional coupler as a function of the following: an amplitude and a phase of a coupled forward signal coupled into a forward coupled port of the bidirectional coupler; an amplitude and a phase of a coupled reverse signal coupled into a reverse coupled port of the bidirectional coupler; an electrical transmission parameter from an input port of the bidirectional coupler to the forward coupled port; an electrical transmission parameter from the input port to the reverse coupled port; and an electrical transmission parameter from an output port of the bidirectional coupler to the reverse coupled port.

Herein disclosed in some embodiments is a fault detector for power amplifiers of a communication system. The fault detector can detect a portion of the power amplifiers that are in fault condition and can prevent or limit current flow to the power amplifiers in fault condition while allowing the rest of the power amplifiers to operate normally. The fault detector can further indicate which power amplifiers are in fault condition and/or the cause for the power amplifiers to be in fault condition. Based on the indication, a controller can direct communications away from the power amplifiers in fault condition and/or perform operations to correct the fault condition.

The present disclosure relates to an envelope tracking system that is configured to improve the performance of radio frequency power amplifier circuitry by compensating for errors that become more significant as modulation bandwidth increases. These errors include power amplifier collector-base capacitance, time delay between power amplifier stages, and interconnect distance between the baseband modulation source and the power amplifier collector.

Interference with another system can be appropriately avoided. Provided is a communication apparatus including: a receiver that performs reception of power from another system; a determination unit that determines presence or absence of interference with the other system on the basis of the reception; and a transmitter that transmits first interference information including information relating to the interference to another communication apparatus.

A low noise block down converter for receiving satellite broadcasting comprises an input terminal; a low noise amplifying unit including one or more low noise amplifiers configured to amplify a signal received from the input terminal, and a built-in cavity waveguide band pass filter configured to pass a frequency band being higher or lower than a frequency band of a predetermined terrestrial transmission signal among satellite broadcasting frequency bands of signals amplified by the one or more low noise amplifiers; and a mixer configured to convert the signal output from the low noise amplifying unit into an intermediate frequency signal by mixing the signal output from the low noise amplifying unit with a local oscillation signal.

Herein disclosed in some embodiments is a fault detector for power amplifiers of a communication system. The fault detector can detect a portion of the power amplifiers that are in fault condition and can prevent or limit current flow to the power amplifiers in fault condition while allowing the rest of the power amplifiers to operate normally. The fault detector can further indicate which power amplifiers are in fault condition and/or the cause for the power amplifiers to be in fault condition. Based on the indication, a controller can direct communications away from the power amplifiers in fault condition and/or perform operations to correct the fault condition.

Disclosed is a double-path switching TX power detection circuit. A first detection module is separately connected to a power supply, a first radio frequency connector, and a second radio frequency connector; a second detection unit is connected to the second radio frequency connector; the first detection module and the second detection module control a current path of the power supply according to access states of the first radio frequency connector and the second radio frequency connector, respectively; the first detection module outputs a corresponding detection level signal, to determine whether a switching TX power function is enabled or disabled.

An amplifying apparatus is provided, which includes a power-source main line, a plurality of amplifying control devices which include an amplifier, a power-source branch line, an over current protector. The amplifier amplifies a high-frequency signal. The power-source branch line is branched from the power-source main line. The over current protector disposed for the power-source branch line is connected to the amplifier and configured to disconnect the power-source branch line based on drive current flowing through the amplifier from the power-source branch line. The power-source main line is common to the plurality of amplifying control devices.