Abstract: A sound-activated control system includes an audio receiver and a command discriminator. The receiver is configured to receive an audio waveform and to produce a digital audio waveform therefrom. The command discriminator is configured to detect a temporally and/or spectrally compact nonphonetic audio command within the digital audio waveform and to control a voice-activated system an action in response to the nonphonetic command.

Abstract: An electronic device is configured to receive data from a keypad key, wherein the key is associated with first and second alphanumeric characters. The device includes a keypad interface and a data entry processor. The keypad interface is configured to determine the first and second alphanumeric characters when the key is pressed. The data entry processor is configured to select the first alphanumeric character from among the first and second alphanumeric characters when a speech recognizer determines that a spoken entry identifies the first alphanumeric character.

Abstract: A sound-activated control system includes an audio receiver and a command discriminator. The receiver is configured to receive an audio waveform and to produce a digital audio waveform therefrom. The command discriminator is configured to detect a temporally and/or spectrally compact nonphonetic audio command within the digital audio waveform and to control a voice-activated system an action in response to the nonphonetic command.

Abstract: One aspect of the invention includes a communication system that includes a tone generator configured to generate a first tone, a second tone, and a third tone. The third tone can have a frequency that is a harmonic product of at least one of the frequencies of the first and second tones. A transmitter that includes a predistortion system transmits a test signal comprising the first, second, and third tones. A receiver that is communicatively coupled to the transmitter receives and processes a received test signal corresponding to the test signal. The system further includes a controller that generates a set of correction coefficients based on a measured interaction of the third tone with a non-linear signal component in the received test signal. The set of correction coefficients can be provided to the predistortion system for substantially linearizing communication signals transmitted from the transmitter.

Abstract: A method for measuring noise parameters includes generating a noise signal at a noise source. The noise signal includes a first input signal at a first frequency and a second input signal at a second frequency. The first input signal and the second input signal are modulated onto a carrier to generate a modulated signal. The modulated signal is attenuated to a desired power level and applied to a device under test to obtain a noise measurement.