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A preliminary design and implementation of a Telemetry and Telecommand (T&Tc) subsystem is presented by using Commercial Off The Shelf (COTS) modules. Telemetry data are collected, stored, and then transmitted to the Ground Station (GS). Commands are executed in both autonomous and GS controlling modes. Commands are executed on the On Board Computer (OBC) according to prepared scheduled commands and patch files. Updated patch files can be loaded from the Ground Control Center (GCC) to the OBC.

A rectangular planar array antenna design using thinning technique and Genetic Algorithm (GA) optimization technique are used to minimize the gain variation for Low Earth Orbit (LEO) satellites antenna. This design controls the feeding amplitude through thinning without requirements to control the phases which yields to simplify the feeding network. Two antenna elements are proposed, cos 1.5 radiation pattern element and the rectangular patch element. A simple genetic algorithm optimizer is used to get the optimum excited elements on the array.