Audio signal processing

About: Audio signal processing is a research topic. Over the lifetime, 21463 publications have been published within this topic receiving 319597 citations. The topic is also known as: audio processing & Acoustic signal processing.

Navigation with auditory cues in a virtual environment

Abstract: The authors use 3D sound to help navigate an immersive virtual environment and report results of user tests obtained with a game-like application. The results show that auditory cues help in navigation, and auditory navigation is possible even without any visual feedback. The best performance is obtained in audiovisual navigation where auditory cues indicate the approximate direction and visual cues help in the final approach.

Digital radio paging communication system

Abstract: A digital paging communication system including a transmitter and a plurality of receivers is disclosed. The transmitter generates a preamble digital signal, a calling digital signal and an end mark digital signal in a predetermined sequence. Each receiver demodulates a received signal into the preamble digital signal, calling digital signal and end mark digital signal. These signals are separately detected in synchronism with a recovered clock signal. Power is supplied to the radio frequency, intermediate frequency and demodulator sections of the receiver intermittently until such time as the calling signal of the receiver is detected, after which power is supplied continuously until an end mark signal is detected. The intermittent operation is a battery saving feature.

Digital sound data storing device

Abstract: This invention relates to a digital sound data storing device wherein analog sound data is synthesized from digital sound data. The device includes a case and an IC card detachably attached to the case. A plurality of digitized sound data groups are stored at a built-in memory of the IC card. The digitized sound data groups are obtained by recording sentences for foreign language conversation practice through a microphone to thereby obtain analog sound signal which is converted to digital sound signal. When the IC card is attached to the case, a signal processing circuit operates to read out the digital sound data group, which is converted to the analog sound signal. The analog sound signal is supplied to an amplifying circuit and reproduced as sound.

Self configuring multi-mode communications terminal

Abstract: A communications terminal adapts to different operating standards by using software algorithms and digital processing instead of physically dedicated hardware. The communications terminal includes digital processing circuits (103) having a digital signal processor and microprocessor circuits, volatile and non-volatile memory, signal characteristics stored in memory and receiver circuitry to receive and digitize a radio signal. The communications terminal receives the radio signal, converts the radio signal into a digital signal and compares the signal characteristics of the digital signal to signal characteriscs of stored signals. The comparison of the signals identifies the standard of the radio signal and determines the format and protocol of the signal. The hardware is then reconfigured to operate according to the identified standard, format and protocol.

Time-frequency segmentation of bird song in noisy acoustic environments

Abstract: Recent work in machine learning considers the problem of identifying bird species from an audio recording. Most methods require segmentation to isolate each syllable of bird call in input audio. Energy-based time-domain segmentation has been successfully applied to low-noise, single-bird recordings. However, audio from automated field recorders contains too much noise for such methods, so a more robust segmentation method is required. We propose a supervised time-frequency audio segmentation method using a Random Forest classifier, to extract syllables of bird call from a noisy signal. When applied to a test data set of 625 field-collected audio segments, our method isolates 93.6% of the acoustic energy of bird song with a false positive rate of 8.6%, outperforming energy thresholding.