Topic
Digital signal
About: Digital signal is a research topic. Over the lifetime, 44213 publications have been published within this topic receiving 345279 citations.
Papers published on a yearly basis
Papers
More filters
03 Apr 1990
TL;DR: A new technique is proposed which makes possible the inaudible addition of extra information to an audio signal, and the so-called 4-2-4 coding is presented, as the technique presented offers a very promising scheme for such a coding.
Abstract: A new technique is proposed which makes possible the inaudible addition of extra information to an audio signal. Full compatibility with present-day transmission and reproduction systems is guaranteed, as the resulting signal remains in the same format. The extra information can be retrieved by the use of additional signal processing. The technique of adding and retrieving extra information is described, and applications are presented. Special attention is given to the so-called 4-2-4 coding, as the technique presented offers a very promising scheme for such a coding. >
89 citations
Patent•
28 Oct 2004
TL;DR: In this paper, a capacitive isolation barrier across which a digital signal is communicated is provided, where clock recovery circuitry is employed on one side of the barrier to extract timing information from the digital signal communicated across the barrier, and to filter the effects of phase noise introduced at the barrier.
Abstract: An isolation system is provided that is suitable for use in telephony, medical instrumentation, industrial process control and other applications. Preferred embodiments of the invention comprise a capacitive isolation barrier across which a digital signal is communicated. The system provides a means of communication across the isolation barrier that is highly immune to amplitude and phase noise interference. Clock recovery circuitry may be employed on one side of the isolation barrier to extract timing information from the digital signal communicated across the barrier, and to filter the effects of phase noise introduced at the barrier. Delta-sigma converters may be disposed on both sides of the isolation barrier to convert signals between analog and digital domains. An isolated power supply may also be provided on the isolated side of the barrier, whereby direct current is generated in response to the digital data received across the isolation barrier. A bidirectional isolation system is provided whereby bidirectional communication of digital signals is accomplished using a single pair of isolation capacitors. In preferred embodiments, the digital data communicated across the barrier consists of digital delta-sigma data signals multiplexed in time with other digital control, signaling and framing information. Finally, the isolation system may include a pulse transformer to accommodate ADSL circuitry, whereby power is transmitted through the pulse transformer.
89 citations
Patent•
29 Jun 2009
TL;DR: An intelligent electronic device for monitoring and determining an amount of electrical power usage by a consumer, or end user, and for providing broadband Internet access to the consumer is described in this paper.
Abstract: An intelligent electronic device for monitoring and determining an amount of electrical power usage by a consumer, or end user, and for providing broadband Internet access to the consumer. The intelligent electronic device includes at least one sensor coupled to an electric circuit configured for measuring at least one power parameter of the electrical circuit and generating at least one analog signal indicative of the at least one power parameter; at least one digital to analog converter coupled to the at least one sensor configured for receiving the at least one analog signal and converting the at least one analog signal to at least one digital signal; a processor configured for receiving the at least one digital signal and calculating energy consumption in the electrical circuit; and a gateway configured for receiving data transmissions imposed on the electrical circuit and for demodulating the imposed data transmission for providing data communications.
89 citations
Patent•
11 Sep 1996TL;DR: In this article, a portable self-contained data collection system (100) for measuring and collecting vibration data from machines includes an accelerometer (160) which is coupled to the analog input of a data acquisition card (120).
Abstract: A portable self-contained data collection system (100) for measuring and collecting vibration data from machines includes an accelerometer (160) which is coupled to the analog input of a data acquisition card (120). The data acquisition card (120) samples and digitizes the analog signal to produce a time domain digital signal. The data acquisition card output (122) is coupled to a battery-powered portable computer (110). The battery-powered portable computer (110) includes a database (220) having machine identifications and associated measurement parameters. The portable computer (110) processes the time domain digital signal according to the measurement parameters associated with a selected machine identification, and produces a frequency domain digital signal by performing a Fast Fourier Transform and other digital signal processing operations. The frequency domain signal is also analyzed in the portable computer (110) to produce predictive maintenance information. A power supply (150) for supplying power to the accelerometer (160) is also included. The accelerometer power supply (150) electrically and mechanically couples the accelerometer (160) to the data acquisition card (120). It supplies power to the accelerometer (160) when the data acquisition card is activated. The portable self-contained data collection system (100) can be used to measure and collect vibration data from machines and to analyze this data to produce predictive maintenance information.
89 citations