WIRELESS COMMUNCATIONS

 Keerthana
1st Sem BCA, NCMS

Wireless communication is a method of transmitting information from one point to other , without using any connection like wires, cables or any physical medium. In the year 1897, GUGLIELMO MARCONI successfully demonstrated the wireless telegraphy by sending EM waves for short distance of 100 meters. Since the use of smoke signals, flags and flashing mirrors in the pre-historic period, wireless communications has been a part of human life and is continuously evolving. Throughout the development of wireless communication, there are many wireless systems and methods that flourished and many got disappeared. The best example for this is Telephone communication and Television transmission. Initially, all telephone related communications were carried out using wired network. But the rapid growth of mobile communication started to replace the complex wired telephone system. Now the wired technology became outdated and got replaced by wireless communication.

WORKING:

The transmitter takes information like audio or video, encodes it into a sine function, and transmits the function into the air in the form of an electromagnetic wave. The receiver detects the wave and decodes the data. Antennas are used by both transmitters to transmit waves and by receivers to detect them. Wireless communications involves transfers without any physical connections between two or more points. Because of the absence of any physical infrastructures.

Main components of a wireless network;

1. Wireless access points.
2. Network interface cards. 

Advantages of wireless communications:

• COST: The cost of installing wires, cables and other infrastructures is eliminated.
• MOBILITY: Freedom to move around while still connected to network.
• EASE OF INSTALLATION: Setup and installation of these communications networks equipment and infrastructure is very easy and no worry about hassle of cables.
• RELIABILITY: Since there are no cables there will be no chance of damage of cables.
• DISASTER RECOVERY: During floods or disasters, the loss of communication infrastructures can be minimal.

Applications of wireless communications in various fields:

• GPS
• Infrared communication
• Radar
• Wifi
• Bluetooth
• Cordless phones
• Satellite communications