The cellular network is an invisible path and its operation is a mystery to many, it is at the very centre of the overall cellular system and the success of the whole end to end system is dependent largely on its performance. Cellular networks have evolved significantly over the generations. It also has brought many new specifications technologies and solutions to the modern era. Cellular networks are mobile device communication through radio waves and the cellular architectures are designed in order to share information globally. Though different systems take different approaches to cellular networks, the basic concepts are similar.


CELLULAR NETWORK ARCHITECTURE:
A cellular network basically consist of partitions called cells or cell sites. Each cell site consists of one or more transceivers which enables world wide communication. The cells are responsible for the connection of phone exchanges and also for internet access. The cells are placed adjacent to each other to ensure communication over a wide range. The cells are usually shaped hexagonally but it can also be square or circle. Regardless of the shapes the signal coverage usually overlaps the adjacent cell to ensure if the user is in the coverage area.

The cell coverage area can widely vary from 10 meter to 25 miles depending on the factors like configuration , size , environmental characteristics etc,. The placement of cells requires careful analysis by the communication providers who should take into account terrain and reception characteristics. Additionally , repeater cells can be built for better communication.

CELLULAR NETWORK STRUCTURE:

Considering the overall cellular network it contains a number of different elements from the base transceiver station (BTS) itself with its antenna back through a base station controller (BSC), and a mobile switching centre (MSC) to the location registers and the link to the public switched telephone network (PSTN).

BTS: It consists of a number of different elements . Firstly the electronics part located in the container at the base of the lower antenna which is responsible for the communication of mobile phones , radio frequencies and also acts as the power backup. Second is the antenna and the feeder. Finally the interface between the base station and its controller. BTS are often set up in tall buildings. There is more concern about the location and orientation because of the reception status of the signals.

MCS: In view of the importance of the MSC, it contains many backup and duplicate circuits to ensure that it does not fail. It is obvious that backup power systems are the vital elements of this to guard against the possibility of a major power failure, because if the MSC became inoperative then the whole network would collapse.

CELLULAR NETWORK TECHNOLOGIES:
To standardize cellular network communications, a number of new technologies have been developed over the modern era which includes GSM, GPRS , EDGE, UMTS, LTE etc., The introduction of GSM with 2G arguably defined many of the core elements we recognize in our cellular networks today. Cellular networks have also gone on to become the underlying connectivity platform for new applications including IoT devices, robotics, virtual and augmented reality, and mobile gaming. Now, 5G is taking shape and ushering in new possibilities .