**SIGNAL&SYESTEM(1) **

*What is a ***signal**?Generally, Every sign represents it.So everything around us represents it.Likewise, your is using a smart-phone, it’s a **cellular network**.

**signal**?

A **cellular network** or **mobile network** is wireless based **communication system**.Also known as a network signal.Digital signboards represent a digital signal.

How about an electric or a radio signal.

A** signal** is an electric current or electromagnetic field.It conveys data from one place to another. The simplest form of signal is a direct current (DC).That is switched on and off and it is represented as ‘0’ & ’1’ in a digital logic gate.This is the same principle by which the early telegraph worked. More **complex signals** consist of an alternating-current (AC) or electromagnetic carrier that contains one or more data streams.

The concept of it is mainly based on waveforms. A **waveform** is the shape and form of a signal such as a wave moving in a physical medium or on a discrete object.

Basically, there are two types of signals –

**Continuous****Discrete**

** **

**Continuous signals** are defined and represented at any instant of time.The phase shift 180° happens in infinite time sequence. These signals have a finite or infinite sequence with time.** Continuous **is** **also called **analog signals**. The examples of continuous are sine, cosine, and triangular waves.

Figure 1(a) represents it,

Now let’s discuss this continuous wave.First question, why this is a continuous wave?We all can see the wave has a starting value of 1 (this value can be any number ). λ represents wavelength and X-axis is time division. Now, this is a continuous signal because in the figure the wave is represented by instant time.

**Discrete signals** are defined and represented at the certain time. Here the time sequence a finite or countable set. **Discrete **is also called **digitalized signals**.

Figure 1(b) represents it,

In the figure the time (t) is countable.So, this signal is called a discrete signal.

As there are the more signals. **Deterministic** **&** **Non-deterministic **.Also known as a** random** **signal**.**Periodic & Aperiodic** and** Even & Odd** are discussed in the next blog.

For any question comment in the comment section.