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For the following signals, determine if the signal is an energy signal, power signal, or neither. If the signal is a power signal, find its power. If the signal is an energy signal, find its energy.

User Ffabri
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Answer:

The energy signal is a signal that has energy only in a finite time, not all the time. And as we know, the power of a signal is the speed of its energy over time ... that is (energy / time). So, in the energy signal (power = energy (finite) / time (infinite) [at all times]) that is equivalent to ZERO

Power Signal is a signal that has a finite power (not equal to ZERO) ... and as we said earlier that (power = energy / (infinite) time [at all times]). So, the energy is very very large that tends to infinity

Step-by-step explanation:

E = ∫V2 (t) Rdt

if V (t) = x (t)

and R = 1Ω

E = ∫V2 (t) dt

The energy and power expression is expressed as a normalized expression (calculated at R = 1Ω)

The energy of a signal (complex or real) is given by

E = ∫∞ - ∞ | x2 (t) | dt

The power of a signal (when it is periodic) is given by

P = 1T∫T | x2 (t) | dt

The power of a signal (when it is not periodic) is given by

P = limT → ∞1T∫T2 - T2 | x2 (t) | dt

POWER SIGNALS

⇒ A signal is said to be an energy signal if it has a finite amount of associated energy.

E → finite

P → 0

⇒ A signal will have a finite amount of energy if it is absolutely integrable

∫∞ - ∞ | x (t) | dt <∞

Example 1

x (t) = e - atu (t)

go> 0

∫∞0e - atdt = 1a⇒

Energy signal

E = ∫∞ - ∞e - 2atdt = 12a

Example 2

x (t). = e - a | t |

go> 0

x (t) = e - atu (t) eatu (−t)

go> 0

∫∞0e - atdt ∫0 - ∞eatdt = 1st 1a⇒

Energy signal

E = ∫0 - ∞e2atdt ∫∞0e - 2atdt = 12a 12a = 1a

Example 3

x (t) = eatu (t)

go> 0

∫∞0eatdt → ∞⇒

It is not an energy signal

Example 4

x (t) = Au (t)

∫∞0dt → ∞⇒

It is not an energy signal

Example 5

x (t) = sin (ω0t)

∫∞ - ∞ | sin (ω0t) | dt → ∞⇒

It is not an energy signal

User Rydgaze
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