Aspects of the subject technology relate to a device including a microphone, a filter and a processor. The filter receives an audio signal including ambient noise and a voice of a user of the device from the microphone. At least a portion of ambient noise is filtered from the audio signal. The processor determines a level of the ambient noise in the received audio signal and dynamically adjusts a gain applied to the filtered audio signal based on the level of the ambient noise.

An apparatus for amplifying an audio source includes a speaker and a chip. The chip includes a processor configured to generate a signal and an amplifier element configured to amplify the signal into an amplified signal. The chip further includes a current monitor configured to monitor the current of the amplified signal prior to the amplified signal being output from the chip to the speaker and a voltage monitor configured to monitor the voltage of the amplified signal prior to the amplified signal being output from the chip to the speaker. The processor of the chip is configured to control a power of the amplified signal output from the chip to the speaker based at least on the current and the voltage.

A package for a current sense circuit may include a lead-frame having a shunt resistance configured to generate a shunt voltage, which can be used to measure a current through the lead-frame. The shunt resistance associated with the lead-frame may be highly variable with temperature, which can cause errors in the current measurement. Accordingly, a current sense circuit can include an amplifier with an input resistor having a composite temperature coefficient configured to match a lead-frame temperature coefficient so that an output of the amplifier is compensated to remove variations in the shunt resistance of the lead-frame due to temperature.

A method, an apparatus, and logic to post-process raw gains determined by input processing to generate post-processed gains, comprising using one or both of delta gain smoothing and decision-directed gain smoothing. The delta gain smoothing comprises applying a smoothing filter to the raw gain with a smoothing factor that depends on the gain delta: the absolute value of the difference between the raw gain for the current frame and the post-processed gain for a previous frame. The decision-directed gain smoothing comprises converting the raw gain to a signal-to-noise ratio, applying a smoothing filter with a smoothing factor to the signal-to-noise ratio to calculate a smoothed signal-to-noise ratio, and converting the smoothed signal-to-noise ratio to determine the second smoothed gain, with smoothing factor possibly dependent on the gain delta.

Apparatus and methods for vector modulator phase shifters are provided. In certain embodiments, a phase shifter includes a quadrature filter that filters a differential input signal to generate a differential in-phase (I) voltage and a differential quadrature-phase (Q) voltage, an in-phase variable gain amplifier (I-VGA) that amplifies the differential I voltage to generate a differential I current, a quadrature-phase variable gain amplifier (Q-VGA) that amplifies the differential Q voltage to generate a differential Q current, and a current mode combiner that combines the differential I voltage and the differential Q voltage to generate a differential output signal. A phase difference between the differential output signal and the differential input signal is controlled by gain settings of the I-VGA and the Q-VGA.

The processing of audio signals is shown in which a first gain-adjustable amplifier is configured to receive a feed forward signal from an input and a second gain-adjustable amplifier is configured to receive a feedback signal from an output. A gain controller supplies a first gain control signal to the first gain-adjustable amplifier, wherein the gain controller supplies a complementary second gain control signal to the second gain-adjustable amplifier, which may be the reciprocal of the first gain control signal. A first combiner is arranged to combine a first output from the first gain-adjustable amplifier with a second output from the second gain-adjustable amplifier. A plurality of filter elements are configured in parallel, wherein each filter element receives an output from the first combiner. A second combiner combines outputs from the filter elements with the original input signal and the filter elements have mutually different filtering characteristic.

An audio processing apparatus configured to limit a dynamic range of an audio signal includes a variable gain amplifier configured to generate an output signal by amplifying or attenuating an input signal, a level detector configured to detect a level of the input signal or the output signal, and a gain controller configured to perform an attack and a release based on the level and a plurality of threshold values.

An apparatus includes a CPU and a memory storing a program that causes the apparatus to function as the following units. A first amplification unit that amplifies a the sound signal from a first microphone for acquiring an environment sound, a second amplification unit that amplifies a sound signal from a second microphone for acquiring a noise of a noise source in accordance with a amplification amount, a conversion unit that performs Fourier transform on sound signals from the first amplification unit and the second amplification unit, a reduction unit that reduces noise from first sound data using noise data. The amplification amount is set based on at least one of a level of the sound signal from the second amplification unit and a type of the noise source.

A virtual meeting system is discussed herein. An online meeting application can provide a parallel virtual meeting between or among two or more participants of a main virtual meeting. The parallel virtual meeting permits two or more participants of the main virtual meeting to have a “smaller-sized” meeting in parallel with the main virtual speaker or presentation while still participating in the main virtual meeting. Therefore, the participants of the parallel virtual meeting do not have to connect via another device or application and can avoid disrupting the main virtual meeting. The parallel virtual meeting can permit two separate meetings, such as one meeting with all participants and one meeting with a subset of all the participants.

A vibration damping system for a charged particle beam apparatus according to the present invention includes a column through which a charged particle beam passes, a vibration detection unit that detects vibration of the column, a damping mechanism that applies vibration to the column to suppress the vibration of the column, and a control device that controls the damping mechanism. The control device includes a damping gain control unit that amplifies a detection signal of the vibration detection unit with a set amplification factor and outputs an amplified detection signal as a control signal to the damping mechanism, and a saturation suppression unit that adjusts a feedback gain value of the damping gain control unit according to a detection signal of the vibration detection unit, a signal of the damping mechanism, and a maximum output value and a minimum output value of the damping mechanism.