continuous valued or discrete valued signals

continuous valued signals:
if the variation in the amplitude of signals is continuous or discrete in nature ....


discrete valued signals:
if the variation in the amplitude of signals is not continuous ,but the signal has certain discrete amplitude levels then such signals is called as discrete valued signals..........

discrete time signal

in this case the value of signal is specified only at specified only at specific time....
so the signal represented at discrete interval of time is called as the discrete time signal....
the discrete time signal is generated from continuous time signal by using the sampling operation ........

characteristics of discrete time signal:-
1.discrete time sinusoidal signals are identical when there frequencies are separated by integer multiple of 2pi...
2.if the frequency of discrete time sinusoidal is a rational number ,then such signal is periodic in nature.....
3.for the discrete time sinusoidal,the highest oscillation is obtained when angular frequency w=+-pi....

continuous signals

continuous signals
a signal of continuous amplitude or time is known as continuous signal or analog signal....
this signal is having some at every instant of time....

examples of continuous signals:-
1.sine wave
2.cosine waves
3.triangular wave
4.temperature
5.pressure
6.sound

characteristics of continuous signals
1.for every fix value of t,x(t) is a periodic in nature

2.if the frequency (1/t) is increased then the rate of oscillation also changes...

classification of signals

there are various types of signals...every signal is having its own characteristics ....
the processing of signals mainly depends on the characteristics of that particular signal ....
so classification of signal is necessary .....
1.even and odd signals
2.energy and power signals
3.multichannel and multidimensional signals
4.deterministic and radon signals
5.periodic and non periodic signals
6.continuous and discrete valued signals

introduction

in a communication system the word signal is very commonly used ....
therefore we must know its exact meaning:-
let us discuss all about it .......mathematically signal is described as a function of one or more independent variables.
basically it is a physical quantity ....it varies with some dependent or independent variables...
so the term signal is defined as a physical quantity which contains some information and which is function of one or more independent variables...