Python-Based Simulation of Phased Array Beam Degradation and CubeSat On-Orbit Antenna Distortion Modelling

This technical note presents two complementary Python-based simulations exploring antenna beam degradation in practical RF systems. The first models a 20-element phased array digital twin, demonstrating how realistic phase errors (σ=18°) and amplitude mismatches distort a steered beam. The second extends this to a 2U CubeSat S-band (2.4 GHz) patch array in LEO, incorporating thermal cycling (-40°C to +80°C per 90-min orbit), vibration-induced phase drift, and post-launch element failures. Both simulations use only NumPy and Matplotlib.