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| | Im Myrna and was born on 26 February 1971. My hobbies are Baseball and Cooking.<br><br>Here is my blog - [http://Thetimesofusa.com/shingles/index.php?action=profile&u=7693 Fifa 15 Coin Hack] |
| A '''continuous signal''' or a '''continuous-time signal''' is a varying quantity (a [[signal (information theory)|signal]])
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| whose domain, which is often time, is a [[Continuum (set theory)|continuum]] (e.g., a [[connected space|connected]] interval of the [[real number|reals]]). That is, the function's domain is an [[uncountable set]]. The function itself need not be [[continuous function|continuous]]. To contrast, a [[discrete time]] signal has a [[countable set|countable]] domain, like the [[natural number]]s.
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| A signal of continuous amplitude and time is known as a continuous time signal or an analog signal. This (a [[signal (information theory)|signal]]) will have some value at every instant of time.
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| The electrical signals derived in proportion with the physical quantities such as temperature, pressure, sound etc. are generally continuous signals.
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| The other examples of continuous signals are sine wave, cosine wave, triangular wave etc. Some of the continuous signals.
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| The signal is defined over a domain, which may or may not be finite, and there is a functional mapping from the domain to the value of the signal. The continuity of the time variable, in connection with the law of density of [[real numbers]], means that the signal value can be found at any arbitrary point in time.
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| A typical example of an infinite duration signal is:
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| <math>f(t) = \sin(t), \quad t \in \mathbb{R}</math> | |
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| A finite duration counterpart of the above signal could be:
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| <math>f(t) = \sin(t), \quad t \in [-\pi,\pi]</math> and <math>f(t) = 0</math> otherwise.
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| The value of a finite (or infinite) duration signal may or may not be finite. For example,
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| <math>f(t) = \frac{1}{t}, \quad t \in [0,1]</math> and <math>f(t) = 0</math> otherwise,
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| is a finite duration signal but it takes an infinite value for <math>t = 0\,</math>.
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| In many disciplines, the convention is that a continuous signal must always have a finite value, which makes more sense in the case of physical signals.
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| For some purposes, infinite singularities are acceptable as long as the signal is integrable over any finite interval (for example, the <math>t^{-1}</math> signal is not integrable, but <math>t^{-2}</math> is).
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| Any analogue signal is continuous by nature. [[Discrete signal]]s, used in [[digital signal processing]], can be obtained by [[Sampling (signal processing)|sampling]] and [[Quantization (signal processing)|quantization]] of continuous signals.
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| Continuous signal may also be defined over an independent variable other than time. Another very common independent variable is space and is particularly useful in [[image processing]], where two space dimensions are used.
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| == See also == | |
| * [[Discrete time]]
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| {{Time measurement and standards}}
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| [[Category:Signal processing]]
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| {{Signal-processing-stub}}
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Im Myrna and was born on 26 February 1971. My hobbies are Baseball and Cooking.
Here is my blog - Fifa 15 Coin Hack