Optimization of laser satellite communication system through link budget prediction

摘要

Lasercom or laser communication is an optical wireless communication, envisioned to be the next generation wireless communication technology due to its inherent characteristics like increased bandwidth, high data rate, security, immunity to interference, unregulated spectrum etc. Lasercom is a better alternative to conventional communication schemes due to its potential features; terahertz transmission, small Size, Weight and Power (SWaP) components, that which are critical factors in designing space missions. The laser transmit beam however is degraded by atmospheric factors and stringent requirement of line of sight communication results in pointing losses. Lasercom is thus constrained of implementing it in its full potential due to these factors. Therefore unlike RF communication, designing and testing the lasercom system is a complex task, as it needs to take into account many factors related to the conditions that will pertain during the laser communication. These factors are stochastic atmospheric parameters, coordinates of installing the transmitter and receiver, time of commencing the transmission et al. This necessitates the need for a modeling to carry out a virtual laser communication so as to evaluate and optimize the system design. The paper discusses the development of a novel prototype, a testbed combined with an optimizer, named as Lasercom System Optimizer (LSO) that aids the system designer to evaluate and formulate an optimum set of design parameter values. LSO integrates into a single platform, most of the atmospheric models and the various distinct research results that can be included while designing the system for better performance results. These optimum design parameters are generated based on an iterative process with feedback. The paper discusses the design, workflow, final prototype, features and improvisations that can be done.