Name: discrete-time signal basics and shapes
Uploaded: 2024-09-26T13:16:53.000Z
Duration: 1 min 16 s
Channel: JoVE

La sequenza di passi unitari è espressa come 1 per zero e valori positivi di numero intero 'n'. Questo può essere visualizzato graficamente utilizzando una serie di otto punti campione.
L'impulso unitario o la sequenza di campioni è espressa matematicamente per tutti i valori discreti di n. È zero per tutti i valori 'n' tranne che per zero.
L'impulso unitario è la prima differenza del passo unitario, mentre il passo unitario è la somma cumulativa del campione unitario. Questa correlazione è dimostrata visivamente attraverso un grafico.
La sequenza di impulsi unitari può campionare efficacemente il valore del segnale a n uguale a zero poiché è diverso da zero solo in quel punto.
La sequenza di rampa unitaria mostra un'escalation lineare del valore con l'aumento del numero di campioni. Per una sequenza di 12 campioni su una rampa unitaria, il grafico mostra un aumento lineare dell'ampiezza con il numero di campioni.
Una sequenza sinusoidale è definita dai suoi parametri di ampiezza e fase.
La sequenza esponenziale è definita utilizzando numeri complessi, con sequenze esponenzialmente decadenti e crescenti rappresentate su un grafico.

segnali di tempo discreti di base

Basic Discrete Time Signals

La sequenza di step unitari è definita come 1 per i valori 0 e positivi dell'intero n. Questa sequenza può essere visualizzata graficamente utilizzando un set di otto punti campione, che mostrano una funzione step che inizia da n=0 e che inseguito rimane costante.

L'impulso unitario o la sequenza campione è espressa matematicamente come 0 per tutti i valori n tranne che per n=0, dove è 1. La sequenza di impulsi unitari, indicata da δ(n), è la prima differenza della sequenza di step unitari, mentre la sequenza di step unitari u(n) è la somma cumulativa della sequenza di impulsi unitari. Questa relazione può essere dimostrata visivamente tramite un grafico, evidenziando come l'impulso unitario può campionare efficacemente il valore del segnale a n=0.

La sequenza di rampa unitaria mostra un aumento lineare del valore con l'aumento del numero di campioni. Ad esempio, una sequenza di 12 campioni su una rampa unitaria mostrerà un aumento lineare dell'ampiezza con ogni numero di campione, rappresentato graficamente come una linea retta.

Una sequenza sinusoidale è definita dai suoi parametri di ampiezza e fase. Questa sequenza può essere rappresentata come:

<img alt="Equation1" src="/files/ftp_upload/16043/16043_PT%20EQUATION_1.svg" style="height: 14px;">

dove A è l'ampiezza, ω è la frequenza angolare e φ è la fase.

La sequenza esponenziale è definita usando numeri complessi, con sequenze esponenzialmente in decadimento e in aumento rappresentate su un grafico. Una sequenza esponenzialmente in decadimento può essere scritta come:

<img alt="Equation2" src="/files/ftp_upload/16043/16043_PT%20EQUATION_2.svg" style="height: 14px;">

Invece, una sequenza esponenzialmente in aumento è espressa come:

<img alt="Equation3" src="/files/ftp_upload/16043/16043_PT%20EQUATION_3.svg" style="height: 14px;">

dove A è l'ampiezza iniziale e α è una costante positiva. Queste sequenze sono fondamentali nell'analisi di varie applicazioni di elaborazione del segnale grazie alle loro proprietà e ai loro comportamenti unici.

Segnali di tempo discreti di base

La sequenza di passi unitari è espressa come 1 per zero e valori positivi di numero intero 'n'. Questo può essere visualizzato graficamente utilizzando un set di otto ...

Education

Didattica

JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

Introduction to Signals and Systems

Introduzione ai segnali e ai sistemi

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

discrete-time signal basics and shapes

Discrete-time signals include several basic sequences used in signal processing. The unit step sequence is 1 for zero and positive values of the integer n. A graph of eight sample points shows it as a step that begins at n = 0 and stays constant after that.

The unit impulse, also called the sample sequence, is 0 for every n except at n = 0, where it equals 1. This sequence is written as δ(n). It is the first difference of the unit step sequence, and the unit step sequence u(n) is the cumulative sum of the unit impulse sequence. A graph can show how the impulse samples the signal value at n = 0.

The unit ramp sequence increases linearly as the sample number increases. For example, a 12-sample ramp rises by the same amount at each sample, so its graph appears as a straight line. This makes the ramp easy to recognize on a plot.

A sinusoidal sequence is set by its amplitude and phase. In the expression for this sequence, A is the amplitude, ω is the angular frequency, and Φ is the phase. An exponential sequence uses complex numbers. It can describe both exponentially decaying and exponentially increasing sequences. The decaying form and the increasing form are both shown on graphs, with A as the initial amplitude and α as a positive constant. These basic sequences are important because they help describe many signal-processing applications.

Discrete-Time Signal Basics and Shapes

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basic discrete time signals

Discrete-time signals include several basic sequences used in signal processing. The unit step sequence is 1 for zero and positive values of the integer n. A graph of eight sample points shows it as a step that begins at n = 0 and stays constant after that. The unit impulse, also called the sample sequence, is 0 for every n except at n = 0, where it equals 1. This sequence is written as δ(n). It is the first difference of the unit step sequence, and the unit step sequence u(n) is the...

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electrical engineering

Discrete-Time Signal Basics and Shapes

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