According to one embodiment, a low noise amplifier (LNA) circuit includes a first stage which includes: a first transistor; a second transistor coupled to the first transistor; a first inductor coupled in between an input port and a gate of the first transistor; and a second inductor coupled to a source of the first transistor, where the first inductor and the second inductor resonates with a gate capacitance of the first transistor for a dual-resonance. The LNA circuit includes a second stage including a third transistor; a fourth transistor coupled between the third transistor and an output port; and a passive network coupled to a gate of the third transistor. The LNA circuit includes a capacitor coupled in between the first and the second stages, where the capacitor transforms an impedance of the passive network to an optimal load for the first amplifier stage.

Methods and systems are provided for gain control in circuits. Gain applied in a circuit may be set to a baseline set gain. A first baseline parameter, associated with a first feature of a particular pattern of a signal at said baseline set gain, and a second baseline parameter, associated with a second feature of said particular pattern of the signal at said baseline set gain, may be determined. The gain is then set a current set gain, and a gain compression ratio may be determined based on one or more of said first baseline parameter, said second baseline parameter, a first current parameter associated with said first feature of at said current set gain, and a second current parameter associated with said second feature at said current set gain. Said current set gain may then be adjusted until said gain compression ratio reaches a predefined limit.

Systems and methods for improving output stability of an RFPA. The systems may obtain an initial radio frequency signal to be amplified by the RFPA. The systems may also generate a compensated radio frequency signal by performing, based on a preset compensation rule and a set of compensation parameters, a gain compensation operation for the initial radio frequency signal. The set of compensation parameters may include a supply voltage of the RFPA and a transistor junction temperature of the RFPA. The systems may further generate, by performing a non-linear correction operation on the compensated radio frequency signal, a corrected radio frequency signal, which is transmitted to the RFPA.

A receiver includes at least a first amplifier configured to receive a received signal and provide a first amplified signal based thereon, a mixer configured to receive the first amplified signal and provide an intermediate frequency signal based thereon and a second amplifier configured to receive the intermediate frequency signal and provide a second amplified signal based thereon. An automatic gain controller for the receiver is configured to, based on a first overload signal indicative of a first frequency range of the first amplified signal having one or more frequency components exceeding a first maximum signal power threshold and a second overload signal indicative of a second frequency range, narrower than the first, of the second amplified signal having one or more frequency components exceeding a second maximum signal power threshold, provide for control of a respective gain of one or both of the first amplifier and the second amplifier.

Devices, systems and methods for analog automatic gain control (AGC) based on estimated distributions of signal characteristics are described. One example method includes generating a digital measurement of a first signal characteristic based on a second signal characteristic of an input signal received by the device, where the second signal characteristic is based on a level of the input signal. The digital measurement of the signal characteristic is used to update a statistical model for the input signal and the posterior probability distribution of the second signal characteristic conditioned on previous digital measurements of the first signal characteristic. The updated posterior probability distribution is used to generate a gain estimate, which is then used to adjust the power level of the input signal. Another example method may use multiple statistical models for each waveform supported by the system.

A dual-mode switchable power control circuit for an RF transmit signal path of an RF transmitter is switchable between an open-loop automatic gain control (AGC) mode and a closed-loop automatic level control (ALC) mode in the analog domain to provide power control for the RF transmit signal path. The open-loop AGC mode and the closed-loop ALC mode are both controlled based on the analog control signal on the same control line. In the open-loop AGC mode, the analog control signal corresponds to the AGC control voltage indicating a setpoint gain for the RF transmit signal path. In the closed-loop ALC mode, the analog control signal corresponds to an ALC reference voltage indicating a setpoint power output level for the RF transmit signal path.

Disclosed is a broadcast receiver that includes an antenna connector configured to connect with an antenna for receiving a broadcast signal including broadcast content. The broadcast receiver also includes a signal processor configured to generate a reference signal having a strength corresponding to a signal input through the antenna connector and to process the generated reference signal to output an image signal for displaying the broadcast content, and a controller configured to determine whether the antenna is connected to the antenna connector based on an output value of the reference signal and to perform subsequent operations related to whether the antenna is connected based on the determination.

Examples disclosed herein relate to a high gain active relay antenna system. The active relay antenna system comprises a first antenna pair having a first receive antenna and a first transmit antenna to communicate wireless signals in a forward link from a base station to a plurality of users; and a second antenna pair having a second receive antenna and a second transmit antenna to communicate wireless signals in a return link from the plurality of users to the base station. The active relay antenna system further comprises a first active relay section and a second active relay section to provide for adjustable power gain in the wireless signals.

A transmitter circuit includes a power amplifier and a mixer calibration circuit. The power amplifier provides a transmission signal. The mixer calibration circuit receives an incident signal of the transmission signal and a reflected signal of the transmission signal. Based on an amplitude of the reflected signal and on a phase difference between the incident and reflected signals, the mixer calibration circuit determines an amplitude of a standing wave signal. Based on the amplitude of the standing wave signal, the mixer calibration circuit causes a recalibration of an output voltage and the bias current of the power amplifier

Methods and systems are provided for gain control in circuits. Gain applied in a circuit may be set to a baseline set gain. A first baseline parameter, associated with a first feature of a particular pattern of a signal at said baseline set gain, and a second baseline parameter, associated with a second feature of said particular pattern of the signal at said baseline set gain, may be determined. The gain is then set a current set gain, and a gain compression ratio may be determined based on one or more of said first baseline parameter, said second baseline parameter, a first current parameter associated with said first feature of at said current set gain, and a second current parameter associated with said second feature at said current set gain. Said current set gain may then be adjusted until said gain compression ratio reaches a predefined limit.