System Level Simulation of C-Band Transponder and Optimized Link Margin

Satellite communication has become a crucial factor in enabling communication networks all around the globe. The utility of satellites for communication has grown manifold over the past years. The design of a satellite communication system is a complex procedure requiring trade-offs between many factors to achieve the best performance at an acceptable cost. Both, excessive and low margin are undesirable which results in a lot of constraint on the electronic system. In satellite communication, transmitter and receiver are the two systems responsible for commanding and ranging. The analog receiver block used has the potential to have lot of variations due to multiple sources and same is true for the transmitter block. Modern day terrestrial and satellite communication systems demand optimization of each sub-system to achieve the desired specification. In the present world, GEO satellites carry the vast majority of the world's satellite traffic, therefore it becomes of utmost importance to design the link budget with an optimum utilization of the space segment as well as feasibility of transmission of signals over long distances. Though a continuous and a reliable communication link is strongly recommended for all spacecraft operations such as payload data transmission, TT&C signal transmission and reception for all classes of spacecrafts, the accountability of the communication links is very critical during implementation for interplanetary missions or human space missions. This article demonstrates the simulated performance of each block and the performance of the cascaded chain of both transmitter and receiver using System simulation software. Simulated performance of each block provides an opportunity to predict and optimize the performance of each individual block. Further the link budget is calculated and the worst-case analysis is detailed in this article.