A method of operating a radio receiver device comprises receiving a plurality of signals with a plurality of corresponding frequencies; applying respective gains to each of the plurality of signals; and storing the gain applied to each signal and its corresponding frequency. The method comprises subsequently receiving a further signal with a further frequency; and applying a further gain to the further signal. The further gain is determined using at least one of the stored gains according to a difference between the further frequency and at least one of the plurality of corresponding frequencies.

A method of operating a radio receiver device comprises receiving a plurality of signals with a plurality of corresponding frequencies; applying respective gains to each of the plurality of signals; and storing the gain applied to each signal and its corresponding frequency. The method comprises subsequently receiving a further signal with a further frequency; and applying a further gain to the further signal. The further gain is determined using at least one of the stored gains according to a difference between the further frequency and at least one of the plurality of corresponding frequencies.

A high-frequency apparatus includes a resin substrate, a first device including a substrate and provided on the resin substrate, and a second device provided adjacent to the first device on the resin substrate. Each of the first device and the second device includes an acoustic wave device. The second device includes a piezoelectric substrate and a functional element provided on the piezoelectric substrate. The substrate of the first device includes Si or a laminated material including Si. The piezoelectric substrate of the second device includes LiTaO.sub.3, LiNbO.sub.3, or a laminated material including LiTaO.sub.3 or LiNbO.sub.3. The resin substrate includes glass.

A high-frequency apparatus includes a resin substrate, a first device including a substrate and provided on the resin substrate, and a second device provided adjacent to the first device on the resin substrate. Each of the first device and the second device includes an acoustic wave device. The second device includes a piezoelectric substrate and a functional element provided on the piezoelectric substrate. The substrate of the first device includes Si or a laminated material including Si. The piezoelectric substrate of the second device includes LiTaO.sub.3, LiNbO.sub.3, or a laminated material including LiTaO.sub.3 or LiNbO.sub.3. The resin substrate includes glass.

A method and device for downlink signal transmission in a dual-connection architecture, and a terminal. The method comprises: when a first signal receiver and a second signal transmitter both operate, after a second uplink signal and a higher harmonic signal of a first uplink signal enter a first downlink and before entering the first signal receiver, using a notch filter arranged on the first downlink to filter out a signal located in a preset frequency band in the second uplink signal.

A method and device for downlink signal transmission in a dual-connection architecture, and a terminal. The method comprises: when a first signal receiver and a second signal transmitter both operate, after a second uplink signal and a higher harmonic signal of a first uplink signal enter a first downlink and before entering the first signal receiver, using a notch filter arranged on the first downlink to filter out a signal located in a preset frequency band in the second uplink signal.

The present disclosure provides a hetero-integrated terahertz low-noise miniaturized image frequency rejection transceiver front-end, including an intermediate frequency circuit and a terahertz circuit arranged up and down, where the terahertz circuit includes a local oscillator frequency tripler, a 135° 3 dB filter coupler, a radio frequency waveguide power divider, and two quartz hetero-integrated subharmonic mixers; resonant cavities of an input unit, a first output unit, an isolation unit, and a second output unit of the 135° 3 dB filter coupler are sequentially coupled through resonant grooves to form a ring structure, a cavity length of the resonant cavity of the input unit is twice that of the resonant cavities of the other three units, and an electrical length of a waveguide of the first output unit is 45° different from that of a waveguide of the second output unit.

The present disclosure provides a hetero-integrated terahertz low-noise miniaturized image frequency rejection transceiver front-end, including an intermediate frequency circuit and a terahertz circuit arranged up and down, where the terahertz circuit includes a local oscillator frequency tripler, a 135° 3 dB filter coupler, a radio frequency waveguide power divider, and two quartz hetero-integrated subharmonic mixers; resonant cavities of an input unit, a first output unit, an isolation unit, and a second output unit of the 135° 3 dB filter coupler are sequentially coupled through resonant grooves to form a ring structure, a cavity length of the resonant cavity of the input unit is twice that of the resonant cavities of the other three units, and an electrical length of a waveguide of the first output unit is 45° different from that of a waveguide of the second output unit.

The present disclosure provides a GaAs monolithic integrated terahertz low-noise communication system transceiver front-end, including an intermediate frequency circuit and a terahertz circuit. The terahertz circuit includes a local oscillator frequency tripler, a local oscillator unidirectional 3 dB filter coupler, a radio frequency 180° filter coupler, and two terahertz GaAs monolithic integrated subharmonic mixers. The local oscillator unidirectional 3 dB filter coupler and the radio frequency 180° filter coupler each include one ring-cylindrical resonant cavity and four rectangular waveguides. The ring-cylindrical resonant cavity is divided into four rectangular waveguides which are correspondingly connected to the four sector-annular resonant cavities, respectively. The present disclosure suppresses the local oscillator noise by adopting a local oscillator unidirectional 3 dB filter coupler and a radio frequency 180° filter coupler with both coupling and filtering functions, thereby achieving a low local oscillator noise transceiver front-end.

The present disclosure provides a GaAs monolithic integrated terahertz low-noise communication system transceiver front-end, including an intermediate frequency circuit and a terahertz circuit. The terahertz circuit includes a local oscillator frequency tripler, a local oscillator unidirectional 3 dB filter coupler, a radio frequency 180° filter coupler, and two terahertz GaAs monolithic integrated subharmonic mixers. The local oscillator unidirectional 3 dB filter coupler and the radio frequency 180° filter coupler each include one ring-cylindrical resonant cavity and four rectangular waveguides. The ring-cylindrical resonant cavity is divided into four rectangular waveguides which are correspondingly connected to the four sector-annular resonant cavities, respectively. The present disclosure suppresses the local oscillator noise by adopting a local oscillator unidirectional 3 dB filter coupler and a radio frequency 180° filter coupler with both coupling and filtering functions, thereby achieving a low local oscillator noise transceiver front-end.