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GPS BIII-1 (PRN 04)

GPS Navigation Satellite (Block III, First of Generation) · US Space Force

GPS BIII-1 (PRN 04), launched December 2018, is the first satellite of GPS's most significant redesign in decades — and the first GPS satellite ever built with no Selective Availability degradation hardware at all, since SA had already been permanently switched off in 2000 by the time Block III's design was finalized. Block III adds L1C, a new civilian signal specifically engineered to be interoperable with Europe's Galileo system, meaning a single receiver chip can lock onto both American and European satellites simultaneously for better accuracy and reliability. It's also three times more accurate than previous generations and eight times more resistant to jamming.