Abstract: Example apparatus and methods concern performing stereo acoustic echo cancellation using a correlation based filter adaptation control approach and without using stereo de-correlation. An embodiment includes a stereo adaptive filter that produces an echo removed microphone signal from received audio signals. The embodiment includes a mono adaptive filter that produces an echo removed microphone signal from the received audio signals. A correlation detector determines a level of correlation between the received signals and provides a signal to an adaptive filter controller. The adaptive filter controller controls how the stereo adaptive filter and the mono adaptive filter adapt audio echo cancellation as a function of the correlation between the received signals. A signal selector may select for output the signal from either the stereo adaptive filter or the mono adaptive filter based, for example, on the power level of the signals.

Abstract: An exemplary embodiment illustrates an equalization pre-processing method, adapted for characterizing a second sound receptor unit in a sound receiving system based on knowing the internal structure parameters of a first sound receptor unit.

Abstract: Systems and methods are described for enhancing the audio quality of an FM receiver. In embodiments described herein, quadrature L?R demodulation is applied to a composite baseband signal output by an FM demodulator to obtain an L?R noise signal. A channel quality measure is calculated based on the L?R noise signal and is used to control whether a pop suppression technique is applied to an L+R signal obtained from the composite baseband signal to detect and remove noise pulses therefrom. The channel quality measure and the L?R noise signal are also leveraged to perform single-channel noise suppression in the frequency domain on an L?R signal obtained from the composite baseband signal and on the L+R signal. The channel quality measure is also used to control the application of a fast fading compensation process that replaces noisy segments of the L?R and L+R signal with replacement waveforms generated via waveform extrapolation.

Abstract: A thermal control module computes an estimate of a temperature of a speaker, based on an audio signal that is driving the speaker, and computes a gain that is applied to attenuate the audio signal to prevent overheating of the speaker. Thermal control module computes an adapted impedance, being an estimate of the speaker's impedance including its DC resistance, and uses it to compute the temperature estimate. The adapted impedance is obtained from a normal adaptation process when a measured voltage of the speaker is above a threshold, and a decay process when the measured voltage is below the threshold. Other embodiments are also described.

Abstract: A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone is also provided proximate to the speaker to provide an error signal indicative of the effectiveness of the noise cancellation. A secondary path estimating adaptive filter is used to estimate the electro-acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. Adaptation of adaptive filters is sequenced so that update of their coefficients does not cause instability or error in the update. A level of the source audio with respect to the ambient audio can be determined to determine whether the system may generate erroneous anti-noise and/or become unstable.

Abstract: Techniques for ability enhancement are described. Some embodiments provide an ability enhancement facilitator system (“AEFS”) configured to enhance a user's ability to operate or function in a transportation-related context as a pedestrian or a vehicle operator. In one embodiment, the AEFS is configured perform vehicular threat detection based at least in part on analyzing audio signals. An example AEFS receives data that represents an audio signal emitted by a vehicle. The AEFS analyzes the audio signal to determine vehicular threat information, such as that the vehicle may collide with the user. The AEFS then informs the user of the determined vehicular threat information, such as by transmitting a warning to a wearable device configured to present the warning to the user.

Abstract: A personal electronic device (PED) is provided with a system for delivering activity based suggestive (ABS) messages (e.g., a motivational message, etc.) to a user based upon the current or anticipated activity of the user. In some embodiments, the user can define user preferences, which determine when and how ABS messages are initiated. In some embodiments, the message selection is based upon a detected activity, location, or speed of the user. In some embodiments, the message selection is based upon a detection of a local environmental event.

Abstract: The disclosed invention provides the ability for an operator, such as a sonar watch stander, to pay attention to both ambient sounds and system audio sound simultaneously. Further, the disclosed invention allows an operator to hear information being disseminated in the immediate environment, while still maintaining full sonar audio capability. The present invention allows the operator to take advantage of the benefits of binaural processing.

Abstract: The approach shown provides for an efficient implementation of time response, level response and frequency response alignment between two audio sources such as DAB and FM that may be time offset from each other by as much as 2 seconds, and produces an aurally undetectable transition between the sources. Computational load is significantly reduced over the approaches known in the prior art.

Abstract: In a flash memory device, after an updated value is copied from a first block to a second block, a block management value of the first block is set to an unused state, and maintenance is performed to erase data from the first block. When performing maintenance, the block management value of the first block B1 is rewritten from “$FFF0” to “$FFFF.” When a reset occurs and the power supply is deactivated during the maintenance, the digit of “$0” in the block management value may become “1” to “E” of the hexadecimal system. In this manner, when the block management value includes a single digit of “1” to “E” and three digits of “F,” the reading of an updated value from the block corresponding to the block management value is restricted.

Abstract: A loudspeaker drive circuit comprises an input for receiving an audio signal and a signal processor for processing the audio signal before application to the loudspeaker. The signal processor processes the audio signal to derive a loudspeaker drive signal which results in the loudspeaker membrane reaching its maximum displacement in both directions of diaphragm displacement.

Abstract: A pair of PWM signals having mutually opposite or identical phases is applied to both terminals of a load to drive the load. An anomaly detection circuit detects a state of change in the pair of PWM signals (PWM+ and PWM?), performs counting operation when at least one PWM signal stops changing, and outputs an anomaly detection signal when the count value becomes a predetermined value.