In this paper, we report a simulation study on the performance enhancement of Praseodymium doped silica fiber amplifiers (PDFAs) in O-band (1270–1350 nm) terms small signal gain, power conversion efficiency (PCE), and output optical by employing bidirectional pumping. The PDFA is examined optimizing length (PDF), its mode-field diameter (MFD) concentration Pr3+. A small-signal peak gain 56.4 dB...