A signal booster is disclosed that includes a first front-end booster, a second front-end booster, a signal combiner device and a main booster. The first front-end booster can include a first signal power level detector and a first gain unit. The second front-end booster can include a second signal power level detector and a second gain unit. The main booster can include a third signal power level detector and a third gain unit. The main booster can further include a fourth signal power level detector and a fourth gain unit. The first front-end booster can further include a fifth signal power level detector and a fifth gain unit. The second front-end booster can further include a sixth signal power level detector and a sixth gain unit.

A variable gain transconductance amplifier includes an amplifier transistor connected to an input node, a cascode transistor having a source connected to a drain of the amplifier transistor and having a drain connected to an output node, and a switching circuit connecting or disconnecting a node to which the amplifier transistor and the cascode transistor are connected to or from a fixed potential in a switchable manner. A variable gain circuit may include the variable gain transconductance amplifier.

One aspect of this disclosure provides an apparatus for wireless communication. The apparatus comprises a low noise amplifier (LNA), an attenuator, and a processing system. The attenuator is configured to receive a signal from the LNA, generate a first attenuated signal based on the received signal, and generate a second attenuated signal based on the received signal. The processing system is configured to measure a first signal strength of the first attenuated signal at a position and measure a second signal strength of the second attenuated signal at the position. The processing system is further configured to determine a first value based on the first signal strength and the second signal strength and determine a second value based on the first attenuated signal and the second attenuated signal. The processing system is also configured to adjust a current of the LNA if the first value exceeds the second value.

A wireless receiver automatic gain control system includes: a coarse amplification subsystem that receives and amplifies a carrier-modulated signal; a demodulator that generates a baseband signal from the amplified carrier-modulated signal; a fine amplification subsystem that amplifies the baseband signal; and a controller connected to the amplification subsystems. The controller: obtains a unified gain value for the amplification subsystems; based on the unified gain value, selects (i) one of a plurality of coarse gain values defining a set of coarse gain steps each spanning a plurality of unified gain steps, and (ii) one of a plurality of fine gain values defining a set of fine gain steps each spanning a single unified gain step; and sets (i) the gain of the coarse amplification subsystem to the selected coarse gain value, and (ii) the gain of the fine amplification subsystem to the selected fine gain value.

Disclosed is a frequency doubler which controls a magnitude of a signal supplied to a virtual ground by adjusting a gain of one-side transistor among transistors receiving differential input signals when outputting a frequency multiplied LO signal through the virtual ground by amplifying the input differential signals by using a differential circuit structure to minimize undesired harmonics characteristics in a frequency doubled signal output by making the magnitudes of two differential signals be the same as each other.

A method for dynamic sizing of a blocker margin by a receiver automatic gain control (AGC) is described. The method includes measuring a wanted signal level and a blocker signal level. The method also includes adjusting a linear target for the wanted signal level at the output of an analog-to-digital converter (ADC) of the receiver based on the blocker signal level. The linear target is adjusted to optimize a wanted signal signal-to-noise ratio (SNR) and the blocker margin. The method further includes adjusting a receiver front-end gain based on the adjusted linear target.

Disclosed herein are systems for and methods of using a mirrored wideband baseband current for automatic gain control of an RF receiver. In an embodiment, a system includes an RF receiver having an adjustable gain and being configured to direct convert a received wideband RF signal to a wideband baseband current signal. The system further includes a current replicator coupled to the receiver and configured to generate a mirrored current of the wideband baseband current signal. The system further includes a wideband signal-level detector configured to receive the mirrored current from the current replicator, and to measure and output a signal-level value of the mirrored current. The system further includes an automatic gain-control circuit configured to receive the signal-level value from the wideband signal-level detector, and to adjust the gain of the receiver based at least in part on the received signal-level value.

Embodiments herein include a replica communication path and monitor circuit to provide increased common mode transient immunity. As its name suggests, the monitor circuit monitors the replica communication path and produces an adjustment signal (common mode transient adjustment signal) to cancel presence of a common mode transient signal in one or more other communication paths conveying data signals.

A receiver includes a low noise amplifier (LNA) configured to amplify an input RF signal using a first current supplied by a first current source, and a voltage controlled oscillator (VCO) for applying an oscillation frequency to the amplified signal by generating an oscillation signal using the first current.

A wireless receiver, which receives a radio wave (RF) signal from a wireless microphone, demodulates an audio signal, and displays an RF reception state proportional to strength of a received signal on an indicator, includes a first frequency conversion(FC) unit generating a first IF signal based on the received RF signal; a second FC unit generating a second IF signal based on the first IF signal; a first received RF strength measuring unit detecting a first level signal from the first IF signal generated by the first FC unit; a second received RF strength measuring unit detecting a second level signal from the second IF signal generated by the second FC unit; and a synthesizing unit synthesizing the first level signal detected by the first received RF strength measuring unit and the second level signal detected by the second received RF strength measuring unit, and outputs a synthesized level signal.