Telecommunications capabilities have increased dramatically in recent years. Especially significant is the introduction and tremendous growth of mobile telephone communications. Given the limitations of current mobile phone communications and the need for truly global person-to- person capabilities, an enhanced satellite-based system is presented as a feasible means to link portable telephones throughout the world. <p>Using systems engineering and the systems approach, the choice of using a satellite system vice other methods is made from a feasibility analysis. Following this choice, operational requirements are established. Based upon these requirements, two different satellite constellations are presented for consideration: a three-satellite geosynchronous constellation and a multi-satellite low earth orbiting (LEO) constellatIon. The advantages and disadvantages of each configuration are explored and the LEO constellation is chosen. Throughout the paper, systems engineering and its methodologies are used to illustrate how such a system might be developed using the systems approach. / Master of Engineering