%0 Journal Article %T Microwave Attenuation and Prediction of Rain Outage for Wireless Networks in Pakistan's Tropical Region %A Uzma Siddique %A Laeeq Ahmad %A Gulistan Raja %J International Journal of Microwave Science and Technology %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/714927 %X The microwave attenuation due to rainfall in tropical regions has not been very widely studied yet. In Pakistan's tropical environment, line-of-sight microwave communication links were set up and have been operated for several years to study the microwave attenuation characteristics due to tropical rainfall. In this paper the experimental results are presented, including the cumulative distributions of microwave attenuation and the relationship between specific attenuation and rainfall rate. In addition, a rain outage prediction model is proposed which not only predicts microwave radio link performance but will also be useful in calculating the link degradations due to interference issues. The main focus of this research work has been done keeping in mind the wireless networks of Pakistan. The results show that the rainfall rate, the microwave propagation characteristics, and outage predictions in Pakistan differ from the International Radio Consultative Committee predictions and ITU recommendation P530.7/8, respectively. 1. Introduction Mobile operators are deploying increasingly complex wireless networks, and they need to optimize network performance to attract customers, reduce complexity, and get the most out of their network investment. To be successful, mobile operators must maximize transmissions network capacity and performance during the initial network design and throughout the life of the network by addressing all the factors that can affect network performance such as, terrain, irregular network layout, traffic distribution, new service offers, and an increasing subscriber base. Existing GSM transmissions networks in Pakistan suffer from a number of issues including reliability, performance due to usage of inaccurate rain statistics, and lack of offering the desired quality of services to their mobile subscribers. To study the microwave propagation characteristics, experiments have been carried out in Pakistan. Previously published articles have introduced the setup of the experiment, analysed the microwave attenuation due to rainfall at 21.225£¿GHz, proposed the cumulative distributions of attenuation and attenuation duration at frequencies of 15 and 38.6£¿GHz, and also obtained the frequency scaling empirical formulae. The experimental results obtained in Pakistan differ from the CCIR predictions [1]. The aims and objectives of this paper are to provide correct rain statistics for Pakistan region, impact of rain statistics on communication, and cumulative distribution of microwave attenuation and finally to propose a solution in order to %U http://www.hindawi.com/journals/ijmst/2011/714927/