ABSTRACT

Nowadays wireless communication plays very role in the field of telecommunication. Wireless broadband communication in small area coverage (Wi­ Fi) got successful implementation in networking so now researchers move forward to implement wireless service in large or wide area coverage (WiMAX). Worldwide Interoperability Microwave Access (WiMAX) is the latest broadband technology that provide broadcast services in Metropolitan Area Network (MANs). WiMAX sends data from one device to another device via signals i.e. radio signals. The main advantage of WiMAX is that it transmit data up to 70 megabits per second and the coverage distance of WiMAX is 30 miles (50 km) with wireless access. In the deployment of wireless network, projection of signal path loss is very important step. When signals travel from source to destination via radio signals they decreases their energy. So how much energy or strength is decreased by signals it is calculated by models known as path loss models. Path loss means when signal travel in space then.
it reduces its power or its strength. The term path loss plays very important role in the testing of a telecommunication system. When signal cover more distance and passes from more obstacles (building, trees etc.) then it reduces its more energy. There are many path loss models which are already available through which it can be calculate how much energy of signal or how much strength of signal is decreased when they cover some distance. These path loss models are Cost 231 Hata model, Walfisch lkegami model, Lee model, Ericsson model, Free Space model, ECC33 model and Stanford University Interim (SUI) model. By the help of these models it can be examines how much the strength of signal is decrease when they travel in space.