Wave Theory

What is a Wave?

A Wave is nothing but sort of disturbance created in a medium,in to-and-fro motion.
Wave is used to carry the energy through a medium.

What is Medium?

A Medium either a object or air which makes waves or helps waves to travel through it.
Example : Water, Air, Sheets

Types of Waves:

Transverse Waves
Longitudinal Waves

Transverse Waves:

• Waves travelling perpendicular to the direction of medium.
• Transverse Wave consists of Crests and Through.

Crest : Wave moving to maximum position. 

Trough : Wave moving towards least position. 

Equilibrium : Rest position of wave.

   Examples:

• Light and Water waves.

Longitudinal Waves:

• Waves travelling parallel to the direction of medium.
• Longitudinal Waves consists of Compression and Rarefaction.

Compression: Region where particles are closest to each other.

Rare Faction: Region where particles are far to each other.

 Amplitude : 

The distance between the equilibrium and trough or length between the equilibrium and Crest.

Wavelength: 

• The distance between two consecutive compression or two consecutive Rare-Fraction.
• The distance between two Crests or two trough.
• Wavelength is denoted by lambda.

Frequency:

• Time taken for wave to move one full length.
• Frequency depends on the wavelength.
• Higher the  wavelength, lower the frequency.
• Lower the wavelength, higher the frequency.
• Measured in Hertz or Cycles Per Second.

Spectrum:

Range of radio wave that are used for communication.

Spectrum is introduced in order to make different communication not to intercept.

Each Communication System is divided into different frequencies.

 FM Radio - 100MHz-200MHz.

 Telecom   -  800MHz - 2300MHz.

 Wifi          -  2400MHz.

Generations:

	1G	2G	3G	4G
Year	1985	1990	2003	2011
Speed	2.5kbps	64kbps-144Kbps	144kbps-2Mbps	100Mbps-1Gbps
Type	FDMA	GSM(Global System for Mobile Communication),Edge,CDMA(Code Division Multiple Access)	HSPA,HSPA+	LTE
Features	Voice through analog	Digital Voice Calls, Multimedia Messages(MMS), Short Message Service(SMS),    Low data speed.	Video Calls, Higher Data Speed, Video Messages.	Voice Over Data, Faster Data Speed, HD streaming, High Security
Drawbacks	Poor Voice Quality, No Security, Limited Capacity, Frequent Call Drops.	Cell Towers as limited Coverage Area, Unable to support complex data such as video.	High Bandwidth Requirement	Complex hardware structure.

Audible Frequency:

• Audible Frequency is nothing but frequency of sound the a human beings or animals can hear.
• Audible Frequency of human hear is 20MHz to 20000MHz.