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Results tagged with Search options answers only user 11256
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A discrete signal or discrete-time signal is a time series consisting of a sequence of quantities.

In general, it is very hard to estimate the power of a signal after it has gone through an analog front-end and sampled. The front-end filters and mixes the signal, which can amplify or attenuate it. …
answered Oct 30 '14 by MBaz
If I understand correctly, you are mixing a 1500 Hz sinusoid with an MSK signal, which uses 1200 Hz to transmit 0 (or 1) and 1800 Hz to transmit 1 (or 0). The spectrum of the MSK signal, though, is qu …
answered Nov 22 '14 by MBaz
You want to prove that $\frac{nN}{8}$ is an integer for any integer $n$. Consider $n=1$. Clearly, $N$ cannot be less than 8. You also need to prove that $\frac{N^2}{16}$ is an integer. This means tha …
answered Mar 29 '15 by MBaz
There a few variations on the definitions of "energy signal" and "power signal". For example, Sklar in his textook "Digital Communications" defines "energy signal" as a signal with energy $E$ such tha …
answered Feb 25 '18 by MBaz
For the step function $u[n]$ defined as $$u[n]=\begin{cases}1\text{ n\geq0,}\\ 0\text{ otherwise,}\end{cases}$$ the function $x[n]=u[n]+u[-n]$ is given by x[n]=\begin{cases}2\text{ $n=0$,}\\1\text …
answered May 24 '16 by MBaz
In your question, you postulate the existence of two filters, let's say $p(t)$ and $g(t)$, such that $p(t) \star g(t)=\delta(t)$. This assumption is problematic because it implies that $G(f)=1/P(f)$, …
answered Oct 23 '16 by MBaz
Say you're sampling the heart signal at rate $f_s$, so you have $f_s$ samples per second. You have between 1 and 1.67 beats per second. If you plot $f_s$ to $1.67f_s$ samples you'll get one beat, so y …
answered Oct 22 '17 by MBaz
To recover a signal from its samples it is sufficient that: the signal contains no energy at frequencies at or above half the sampling rate that the signal is sampled from $t=-\infty$ to $t=\infty$ …
answered Mar 15 '15 by MBaz
To add to Famous Blue Raincoat's comment: the process of upsampling a signal aims to increase its sampling rate without affecting the signal otherwise. In your example, outputting x or resx through yo …
answered Mar 2 '15 by MBaz
I don't think of the phase as providing information related to position or location. A simple example might be illustrative. In 1-D, consider these two signals, x and y: t = 0:0.001:0.1; x = cos(2*p …
answered Oct 10 '14 by MBaz
There are many factors involved in understanding the theoretical limits to communication. What follows is just a brief introduction that only scratches the surface. First, let's consider a simple sce …
answered Mar 26 '15 by MBaz
Say you quantize a signal with $L=2^n$ levels. Then, every quantized sample is represented by $n$ bits. So, as you increase $L$, you need more and more bits to represent the samples. This means that t …
answered Aug 30 '18 by MBaz
The autocorrelation you obtained shows that the signal becomes decorrelated with itself for specific time delays, which are the zero-crossings of the autocorrelation. The autocorrelation is not zero e …
answered Mar 3 '18 by MBaz
You're missing a step: pulse shaping. The sequence [.7+.7i, ...] is a sequence of pulse amplitudes. As such, it should not be considered to be signal; in consequence, it does not have a spectrum. Say …
answered May 20 '15 by MBaz
Your intuition is correct. When simulating a discrete system, the sampling frequency needs to be high enough that you meet the Nyquist sampling criterion at all times, or you'll have folding. A meth …
answered Aug 13 '17 by MBaz

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