ANALYSIS AND MODELING OF GNSS AUGMENTATION SYSTEM FOR BANGLADESH

Abstract

Satellite communication, certainly is one of the most reliable means of communication nowadays because of its larger coverage, broader bandwidth and ability to provide an incessant communication. In order to enhance the navigation accuracy, augmentation systems for Global Navigation Satellite System (GNSS) have been developed in many countries. These augmentation systems work locally to minimize the computational error so that extreme accuracy can be achieved. To establish an augmentation system is a complex task as many factors need to be considered. Bangladesh being a satellite owning country can aim for developing its own augmentation system provided the major requirements are studied as well as analyzed satisfactorily which will leverage the economic growth and can be a defense asset. Several navigation systems use different satellite constellations for navigation purpose but for an augmentation system the best one or combination should be selected by investigating some of the important relevant parameters. So, a comparison is required among the navigation systems over a particular period of time, surveying at different locations in Bangladesh to detect the best possible system as well as differentiate among the locations based on the parameters. As array antenna has been proven to be more beneficial than a single element antenna as it not only augments the directivity but also enables beam steering capability which is accomplished by establishing a phase difference relation among the antenna elements. Furthermore, selecting location for ground station is significant in augmentation system. The behavior of satellite signal differs in different locations as the environmental condition is not the same. Bangladesh is a subtropical monsoon country having variations in temperature, rainfall and humidity, so these factors along with the parameters will play a vital role in the selection of ground station. In a nut shell, this thesis work aims to perform some of the major criteria to setup an augmentation system for Bangladesh, from analyzing various satellite constellation and comparing among them in order to find out the performance parameters to developing some reference station antennas. Additionally, the atmospheric effects have also been evaluated to find out the signal propagation delay for different cities in order to compare among the cities to find out the location for reference station. Also, uplink and downlink loss analysis has been done by estimating the crucial factors.