copy and paste this google map to your website or blog!
Press copy button and paste into your blog or website.
(Please switch to 'HTML' mode when posting into your blog. Examples: WordPress Example, Blogger Example)
Plotting Discrete-Time Signals - Neil Robertson - DSPRelated. com In this example, x is a pulse signal filtered by a 3 rd order Butterworth filter The filter has a -3 dB frequency of 0 3*f s The following Matlab code creates the pulse and then interpolates it by 8 Figure 4 shows x and the interpolated version As before, the interpolated signal shows every 8 th sample plotted as an orange dot
Fourier Transforms for Continuous Discrete Time Frequency To avoid aliasing upon sampling, the continuous-time signal must be bandlimited to less than half the sampling rate (see Appendix D); this implies that at most complex harmonic components can be nonzero in the original continuous-time signal If is bandlimited to , it can be sampled at intervals of seconds without aliasing (see §D 2) One way
Fourier Transforms for Continuous Discrete Time Frequency Fourier analysis of an indefinitely long discrete-time signal is carried out using the Discrete Time Fourier Transform 3 1 Below, the DTFT is defined, and selected Fourier theorems are stated and proved for the DTFT case Additionally, for completeness, the Fourier Transform (FT) is defined, and selected FT theorems are stated and proved as well
Learn to Use the Discrete Fourier Transform - Neil Robertson Discrete-time sequences arise in many ways: a sequence could be a signal captured by an analog-to-digital converter; a series of measurements; a signal generated by a digital modulator; or simply the coefficients of a digital filter We may wish to know the frequency spectrum of any of these sequences
comp. dsp | Difference between Digital and Discrete Signal A digitized signal is otained most of the time by sampling a discrete signal, once sampled, the signal is digitized (using ADC) For example, in telephony, the signal is sampled at a 8Khz rate, digitized on 13bits, and after digitally compressed using mulaw or alaw
The Discrete Fourier Transform and the Need for Window Functions The Discrete Fourier Transform (DFT) is used to find the frequency spectrum of a discrete-time signal A computationally efficient version called the Fast Fourier Transform (FFT) is normally used to calculate the DFT But, as many have found to their dismay, the FFT, when used alone, usually does not provide an accurate spectrum
Differentiating and integrating discrete signals - Allen Downey Then I show that the cumulative sum (cumsum in Numpy) is the inverse of diff To find the filter that corresponds to cumsum, I find the filter that corresponds to diff and invert it To check the result, I take a signal and its cumulative sum, take the FFT of both, and compute the ratios of corresponding amplitudes
DAC Zero-Order Hold Models - Neil Robertson - DSPRelated. com In DSP math, a discrete-time signal is treated as a sequence of impulses of varying amplitudes Figure 2 (top) shows an example of a DAC’s discrete-time input signal The DAC’s continuous-time output signal is plotted in the middle plot for sample time T = 1 f sDAC As shown, the output signal holds the value of each input sample until the
Demonstrating the Periodic Spectrum of a Sampled Signal Using the DFT My signal was an analog signal that is the product of a sinewave and a pulse train So it does not fit your description of a discrete signal Any analog sinewave above fs 2 will produce an alias below fs 2 when discretized I guess we can believe in the higher frequency images or not, as we prefer Neil
A Differentiator With a Difference - Rick Lyons - DSPRelated. com With that thought in mind, I'll now mention two common discrete-time FIR (nonrecursive) differentiators: a first-difference and a central-difference differentiator They are computationally simple schemes for estimating the derivative of a digital x(n) time-domain signal sequence with respect to time