Digital signal

About: Digital signal is a research topic. Over the lifetime, 44213 publications have been published within this topic receiving 345279 citations.

High speed analog to digital converter

Abstract: An analog to digital converter includes a reference ladder, a track-and-hold amplifier tracking an input signal with its output signal during the phase φ 1 and holding a sampled value during, a coarse analog to digital converter having a plurality of coarse amplifiers each inputting a corresponding tap from the reference ladder and the output signal, a fine analog-to-digital converter having a plurality of fine amplifiers inputting corresponding taps from the reference ladder and the output signal, the taps selected based on outputs of the coarse amplifiers, a clock having phases φ 1 and φ 2 , a circuit responsive to the clock that receives the output signal, the circuit substantially passing the output signal and the corresponding taps to the fine amplifiers during the phase φ 2 and substantially rejecting the output signal and the corresponding taps during the phase φ 1 , and an encoder converting outputs of the coarse and fine amplifiers to an N-bit digital signal representing the input signal.

Digital receiver for spread-spectrum signals

Abstract: The receiver contains a correlator (TIC) for the correlation of the received signal with a reference code (R(k)) and a digital signal processor for evaluating the results of the correlation. The correlator is constructed as digital, time-integrating, multistage correlator (TIC), the individual stages (Kl to KN) of which are connected on the one hand to a digital delay line (17) fed with the reference code (R(k)) and to which on the other hand a digital signal (S(k)) recovered from the received signal is applied, to length (D) of the delay line (17) being adapted to the maximum expected impulse response to the transmission channel.

Communication receiver with signal processing for beam forming and antenna diversity

Abstract: The present invention provides a technique to reduce the number of RF components by using digital signal processing functions in wireless receivers having two or more antennas, which results in the reduction of system cost. The reduction occurs by using a multiplexer or switch to sample the signal received by each of the antennas. The sampling rate of the multiplexer or switch is greater than the Nyquist required sampling rate (Fs) of the received signal bandwidth. The sampled signal is a multiplexed single analog (RF) signal, which only requires one chain of receiver components. A signal processor then is able to demultiplex the received signal at a lower frequency and can perform several functions including antenna diversity and beam forming utilizing digital signals at IF or baseband frequencies.

Packet Video: Modeling and Signal Processing

Abstract: From the Publisher: This book systematically covers both network and signal processing requirements for achieving efficient video communication systems based on fast packet transmission. It describes in detail the features of the emerging broadband digital networks and state-of-the-art digital video signal processing technologies.

Method and apparatus for monitoring instantaneous electrical parameters of a power distribution system

Abstract: A method and a device for monitoring instantaneous electrical parameters of a power distribution system under load utilizing digital control means. An analog signal equivalent to such a parameter is sensed and rated down for processing by solid state components. This signal is converted into a binary coded digital signal having n digits. A plurality of digital signals is sampled and squared values with a format of 2n digits are derived from each sample. The squared values of one sampling period are accumulated to a sum value composed of 2n+m digits and the square root comprising n+k digits of the sum is taken. This value is rescaled to a true root mean square value by performing k left shifts as an accurate measurement result. The core of such device is represented by a microcomputer with built-in analog-to-digital converter.