Abstract: A method and apparatus for processing audio signals. One system includes a communication device including a transceiver configured to send and receive audio data, and a microphone configured to convert sound waves to a first audio signal. A speaker is configured to convert received electrical signals to an acoustic output and is configured to convert sound waves to a second audio signal. An electronic processor connected to the microphone and the speaker is configured to receive the first audio signal from the microphone, receive the second audio signal from the speaker, determine a correlation value between the first audio signal and the second audio signal, and compare the correlation value to a correlation threshold. In response to the correlation value being below the correlation threshold, the electronic processor generates an output signal based on the first audio signal and the second audio signal, and transmits the output signal.

Abstract: A voice activity detection system (100) filters audio input frames (102), on a frame=by-frame basis through a gammatone filterbank (104) to generate filtered gammatone output signals (106). A signal energy calculator (108) takes the filtered gammatone output signals and generates a plurality of energy envelopes. Weighting factors are constructed (112) are applied to each of the energy envelopes thereby producing normalized weighted signal (116), in which voice regions are emphasized and noise regions are minimized. An entropy measurement (118) is taken to extract information from the normalized weighted signals (116) and generate an entropy signal (120). The entropy signal (120) is averaged and compared to an adaptive entropy threshold (122), indicative of a noise floor. Decision logic (124) is used to identifying speech and noise from the comparison of the averaged entropy signal to the adaptive entropy threshold.

Abstract: A voice activity detection system (100) filters audio input frames (102), on a frame=by-frame basis through a gammatone filterbank (104) to generate filtered gammatone output signals (106). A signal energy calculator (108) takes the filtered gammatone output signals and generates a plurality of energy envelopes. Weighting factors are constructed (112) are applied to each of the energy envelopes thereby producing normalized weighted signal (116), in which voice regions are emphasized and noise regions are minimized. An entropy measurement (118) is taken to extract information from the normalized weighted signals (116) and generate an entropy signal (120). The entropy signal (120) is averaged and compared to an adaptive entropy threshold (122), indicative of a noise floor. Decision logic (124) is used to identifying speech and noise from the comparison of the averaged entropy signal to the adaptive entropy threshold.

Abstract: A method and apparatus for receiving and playing a signal in a radio receiver to suppress microphonic feedback are provided by alternately pitch shifting a received audio signal. The pitch of the received audio signal is alternately shifted up and then down, repeatedly over successive intervals of the audio signal, to produce a pitch swing signal which is then played over a speaker. The alternating pitch shifting prevents the buildup of regenerative feedback normally caused by acoustic vibrations coupling into the radio receiver.

Abstract: A portable full duplex communication device (100) is provided with improved acoustic porting (114) by providing an earpiece enclosure (108) within the housing (102) of device. The earpiece enclosure (108) includes an array of micro-ports (114) formed to provide optimal low frequency response and echo performance without the use of external acoustical leak ports to the housing.

Abstract: A method for maintaining transmit audio quality under harsh environmental conditions, the method includes receiving audio signals into a microphone of a portable communication device and determining at least one parameter associated with the received audio signals. In accordance with an embodiment, the at least one parameter is compared with a received audio parameter threshold. When the at least one parameter falls outside of the received audio parameter threshold, the audio routing is switched from the microphone to the loudspeaker. Subsequent communication may revert back to the microphone or remain at the loudspeaker depending on monitored audio conditions.

Abstract: A method and apparatus for receiving and playing a signal in a radio receiver to suppress microphonic feedback are provided by alternately pitch shifting a received audio signal. The pitch of the received audio signal is alternately shifted up and then down, repeatedly over successive intervals of the audio signal, to produce a pitch swing signal which is then played over a speaker. The alternating pitch shifting prevents the buildup of regenerative feedback normally caused by acoustic vibrations coupling into the radio receiver.

Abstract: A portable full duplex communication device (100) is provided with improved acoustic porting (114) by providing an earpiece enclosure (108) within the housing (102) of device. The earpiece enclosure (108) includes an array of micro-ports (114) formed to provide optimal low frequency response and echo performance without the use of external acoustical leak ports to the housing.

Abstract: A method for maintaining transmit audio quality under harsh environmental conditions, the method includes receiving audio signals into a microphone of a portable communication device and determining at least one parameter associated with the received audio signals. In accordance with an embodiment, the at least one parameter is compared with a received audio parameter threshold. When the at least one parameter falls outside of the received audio parameter threshold, the audio routing is switched from the microphone to the loudspeaker. Subsequent communication may revert back to the microphone or remain at the loudspeaker depending on monitored audio conditions.

Abstract: A communications device (100) and method (200) for automatically selecting features of accessories (120,140) operatively coupled to the communications device (100). In use the method (100) includes detecting operative coupling (220) of accessories (120,140) to the communications device (100) and then determining (240) a common feature supported by the accessories (120,140). Thereafter, the method (200) provides for selecting (250) one of the accessories (120,140) to provide the common feature the selecting (250) being determined by a sequence of the operative coupling.