An automatic gain control system for a receiver, including: an automatic gain control loop (40) adapted to be coupled to both a first transimpedance amplifier (12) coupled to a first analog-to-digital converter (14) forming a first tributary and a second transimpedance amplifier (12) coupled to a second analog-to-digital converter (14) forming a second tributary; and an offset gain control voltage to gain balance a transimpedance amplifier gain of the first tributary and a transimpedance amplifier gain of the second tributary. The automatic gain control loop can be analog. Also, the automatic gain control loop can be implemented in hardware or firmware.

An apparatus for providing an output signal to an audio transducer comprises: one or more signal paths for receiving respective digital audio input signals, applying respective digital gains, and outputting respective amplified digital audio input signals; one or more inputs for receiving one or more volume parameters associated with the digital audio input signals; converter circuitry, coupled to the one or more signal paths, for converting the one or more amplified digital audio input signals into the analogue domain, and outputting an analogue audio input signal; an analogue gain element, for applying an analogue gain to the analogue audio input signal and outputting the output signal; and a control circuit, coupled to the one or more signal paths, operative to select the analogue gain based on a comparison of the volume parameters and the one or more digital audio input signals as multiplied by the volume parameters, and to select the respective digital gains for each digital audio input signal so that an overall gain in the respective signal path corresponds to a volume parameter associated with the respective digital audio input signal.

A device includes an analog main signal path and a digital control circuit. The digital control circuit determines and provides a digital control signal to the analog main signal path to reduce a gain error of the analog main signal path.

A method of controlling a signal power of a received signal received by a wireless communication device, the method including: measuring the signal power of the received signal at a plurality of time points in response to a gain control signal; calculating a variance of the signal power of the received signal at at least some time points of the plurality of time points; and controlling the signal power of the received signal based on a gain level determined according to the variance of the signal power of the received signal.

Embodiments described herein provide for smart configuration of audio settings for a playback device. According to an embodiment, while a playback device is a part of a first zone group that includes the playback device and at least one first playback device, the playback device applies a first audio setting. The embodiment also includes the playback device joining a second zone group that includes the playback device and at least one second playback device. The embodiment further includes the playback device applying a second audio setting based on an audio content profile corresponding to the second zone group.

Methods and apparatus to perform an automated gain control protocol with an amplifier based on historical data corresponding to contextual data are disclosed. Example apparatus disclosed herein are to select an automatic gain control (AGC) parameter for an AGC protocol based on historical data corresponding to contextual data, the contextual data including at least one of a time during which the AGC protocol is performed, a panelist identified by a meter, demographics of an audience identified by the meter, a location of the meter, a station identified by the meter, a media type identified by the meter, or a sound pressure level identified by the meter. The disclosed example apparatus are also to perform the AGC protocol based on the selected AGC parameter.

In one embodiment, an apparatus includes: a low noise amplifier (LNA) to receive and amplify a radio frequency (RF) signal, the LNA having a first controllable gain; a mixer to downconvert the RF signal to a second frequency signal; a programmable gain amplifier (PGA) coupled to the mixer to amplify the second frequency signal, the PGA having a second controllable gain; a digitizer to digitize the second frequency signal to a digitized signal; a demodulator coupled to the digitizer to demodulate the digitized signal; an automatic gain control (AGC) circuit to control one or more of the first controllable gain and the second controllable gain; and an AGC settling circuit to cause the demodulator to begin operation in response to determining that the AGC circuit has settled.

Frequency domain compensation is provided for spectral impairment resulting from the audio path characteristics for a given audio device in a given listening space. Selected segments of an audio stream are recorded at a listener position to measure degradation in the audio path and to update compensation filter characteristics of the audio device. Recorded transmitted and received audio sequences are aligned based and compared in the frequency domain. The difference between the aligned transmitted and received sequences represents the frequency domain degradation along the acoustic path due to the speaker, the physical attributes of the room, and noise. A dynamically updated noise model is determined for adjusting compensation filter characteristics of the audio device, which can be updated during use of the audio device. A compensation curve is derived which can adapt the equalization of the audio device passively during normal usage.

The present application relates to the field of audio technology, and provides a method, a device, and an apparatus for playing audio, and a computer-readable storage medium. The method for playing audio includes: obtaining an ambient atmospheric pressure value and audio data to be played; obtaining multiple target frequency points contained in the audio data to be played when the ambient atmospheric pressure value meets a preset condition, and determining equal-loudness multiples corresponding to the target frequency points according to the ambient atmospheric pressure value and a preset calibration atmospheric pressure value; and sending the audio data to be played and the equal-loudness multiples of the target frequency points to a power amplifying module, such that the power amplifying module amplifies the audio data to be played according to the equal-loudness multiples corresponding to the target frequency points.

Exemplary multipath digital microphones described herein can comprise exemplary embodiments of automatic gain control and multipath digital audio signal digital signal processing chains, which allow low power and die size to be achieved as described herein, while still providing a high DR digital microphone systems. Further non-limiting embodiments can facilitate switching between multipath digital audio signal digital signal processing chains while minimizing audible artifacts associated with either the change in the gain automatic gain control amplifiers switching between multipath digital audio signal digital signal processing chains.