Abstract: In a system for performing dual-tone multi-frequency (DTMF) digit detection, an automatic gain controller receives an incoming frame carrying at least one tone sample and adjusts the energy level of the at least one tone sample responsive to the energy level exceeding a frame energy threshold. A single tone detector determines at least one frequency of the at least one tone sample in the incoming frame. A dual tone detector identifies an energy level of each of the determined frequencies and generates an indication of whether a DTMF digit is present in the incoming frame responsive to a first determined frequency corresponding to a frequency in a first grouping of frequencies and a second determined frequency corresponding to a frequency in a second grouping of frequencies. A DTMF digit determiner for determining a DTMF digit based on the indication.

Abstract: In a system for performing dual-tone multi-frequency (DTMF) digit detection, an automatic gain controller receives an incoming frame carrying at least one tone sample and adjusts the energy level of the at least one tone sample responsive to the energy level exceeding a frame energy threshold. A single tone detector determines at least one frequency of the at least one tone sample in the incoming frame. A dual tone detector identifies an energy level of each of the determined frequencies and generates an indication of whether a DTMF digit is present in the incoming frame responsive to a first determined frequency corresponding to a frequency in a first grouping of frequencies and a second determined frequency corresponding to a frequency in a second grouping of frequencies. A DTMF digit determiner for determining a DTMF digit based on the indication.

Abstract: An acoustic processing apparatus is provided. The apparatus includes a pre-processing component, a filter and a first signal processing component. The pre-processing component compensates a non-linearity of a reference signal to generate an input signal. The filter coupled to the pre-processing component, the filter executes filtering on the input signal to generate an output signal. The first signal processing component, coupled to the pre-processing component, the reference signal obtains a gain from the first signal processing component to generate a first signal, and the first signal processing component passes the gain to the pre-processing component.

Abstract: An apparatus for communicating teletype (TTY) messages over a wireless voice link is provided. The apparatus includes a virtual TTY device manager, a display controller, and a keyboard controller. The virtual TTY device manager is disposed within a wireless communication device, and is configured to format first TTY messages for transmission over the wireless voice link, and is configured to extract second TTY messages from frames received over the wireless voice link. The display controller is disposed within the wireless communication device and is coupled to the virtual TTY element, and is configured to present the second TTY messages over a display of the wireless communication device. The keyboard controller is disposed within the wireless communication device and is coupled to the virtual TTY element, and is configured to enable a user to enter the first TTY messages via a keyboard of the wireless communication device.

Abstract: An automatic audio recovery system in a mobile device is provided. The system includes one or more status generators and an audio path recovery handler. The one or more status generators are configured to monitor operation of audio path elements within the mobile device, and are configured to detect and report one or more abnormal audio operations to an audio status monitor, where, responsive to one or more reports corresponding to the one or more abnormal audio operations, the audio status monitor requests automatic recovery of the audio path elements. The audio path recovery handler is configured to receive an automatic recovery request from the audio status monitor, and is configured to responsively direct reset elements corresponding to the audio path elements to automatically initialize the audio path elements to a stable state.

Abstract: An acoustic shock protection device includes a prediction gain estimator and an audio compressor. The prediction gain estimator is configured to analyze a plurality of linear prediction coefficients of an audio signal and determine a category of the audio signal. The audio compressor is coupled to the prediction gain estimator, and the audio compressor is configured to adjust a signal level of the audio signal according to the category of the audio signal.

Abstract: An automatic audio recovery system in a mobile device is provided. The system includes one or more status generators and an audio path recovery handler. The one or more status generators are configured to monitor operation of audio path elements within the mobile device, and are configured to detect and report one or more abnormal audio operations to an audio status monitor, where, responsive to one or more reports corresponding to the one or more abnormal audio operations, the audio status monitor requests automatic recovery of the audio path elements. The audio path recovery handler is configured to receive an automatic recovery request from the audio status monitor, and is configured to responsively direct reset elements corresponding to the audio path elements to automatically initialize the audio path elements to a stable state.

Abstract: A method for detecting a double-talk condition and an echo cancellation system using the same are introduced herein. According to an exemplary embodiment, the method may be adapted to an double-talk detector of an echo cancellation system and includes the following steps: obtaining an input signal with a first power; computing a second power, wherein the second power is a power combination of at least one estimated signal; determining whether the double-talk condition occurs according to a relationship between the first power and the second power, when the first power is larger than the second power, the double-talk condition occurs.

Abstract: A method for detecting a double-talk condition and an echo cancellation system using the same are introduced herein. According to an exemplary embodiment, the method may be adapted to an double-talk detector of an echo cancellation system and includes the following steps: obtaining an input signal with a first power; computing a second power, wherein the second power is a power combination of at least one estimated signal; determining whether the double-talk condition occurs according to a relationship between the first power and the second power, when the first power is larger than the second power, the double-talk condition occurs.

Abstract: An acoustic processing apparatus is provided. The apparatus includes a pre-processing component, a filter and a first signal processing component. The pre-processing component compensates a non-linearity of a reference signal to generate an input signal. The filter coupled to the pre-processing component, the filter executes filtering on the input signal to generate an output signal. The first signal processing component, coupled to the pre-processing component, the reference signal obtains a gain from the first signal processing component to generate a first signal, and the first signal processing component passes the gain to the pre-processing component.

Abstract: An acoustic shock protection device includes a prediction gain estimator and an audio compressor. The prediction gain estimator is configured to analyze a plurality of linear prediction coefficients of an audio signal and determine a category of the audio signal. The audio compressor is coupled to the prediction gain estimator, and the audio compressor is configured to adjust a signal level of the audio signal according to the category of the audio signal.

Abstract: A tri-state pulse density modulator includes a first switch device coupled to a high voltage, and a second switch device coupled to a low voltage. An adder receives a pulse density modulation (PDM) input signal and a latched input signal to generate an output sum signal and a carry signal. A latch module coupled with the adder latches the output sum signal with a clock signal to generate the latched input signal. A control circuit module responsive to the carry signal for selectively turns off the first and second switch devices to generate the PDM output signal at a tri-state voltage between the first and second voltages, or turns on the first or second switch device to generate the PDM output signal at the first or second voltage, respectively. Thus, the PDM output signal only switches between the tri-state voltage and either the first voltage or the second voltage.

Abstract: A tri-state pulse density modulator includes a first switch device coupled to a high voltage, and a second switch device coupled to a low voltage. An adder receives a pulse density modulation (PDM) input signal and a latched input signal to generate an output sum signal and a carry signal. A latch module coupled with the adder latches the output sum signal with a clock signal to generate the latched input signal. A control circuit module responsive to the carry signal for selectively turns off the first and second switch devices to generate the PDM output signal at a tri-state voltage between the first and second voltages, or turns on the first or second switch device to generate the PDM output signal at the first or second voltage, respectively. Thus, the PDM output signal only switches between the tri-state voltage and either the first voltage or the second voltage.

Abstract: A mobile phone having an easy-receive feature for an incoming call includes a body and a receiver coupled to the body and configured to convey voice communication to a user. A microphone is coupled to the body and is configured to convey voice communication from the user. The body has an open position and a closed position. A loudspeaker is coupled to the body. A means for activating the easy-receive feature is coupled to the body and upon activation the mobile phone is configured to answer the incoming call by routing voice communication to the loudspeaker if the body is in the closed position. Otherwise the mobile phone is configured to route voice communication to the receiver if the body is in the open position.