Performance evaluation of O-band praseodymium-doped fiber amplifier with dual-pass regime

ABSTRACT In this work, compact praseodymium-doped fiber amplifiers (PDFAs) with single- and dual-pass configurations are designed and investigated in the O-band region based on theoretical simulation. The impact of doped fiber characteristics, input signal power and input pumping power on the gain and the noise figure of the proposed amplifiers are comprehensively considered and compared. At an input pumping power of 350 mW and optimum praseodymium-doped fiber (PDF) length, the obtained results show that dual-pass model recorded higher gain than the single-pass scheme. This occurs because of the dual propagation of the forwarded and amplified spontaneous emission (ASE) signal through the gain medium. Moreover, both proposed configurations exposed better amplification performance at an input signal power of −10 dB compared to the higher input signal power of 0 dB. The dual-pass regime shows higher amplification gain than the single-pass one of about 4 dB and a maximum power conversion efficiency (PCE) of 14%. Indeed, the PDF core radius and doping concentration are considered as vital factors. Decrement of doped-core radius leads to a notable gain increment and NF decay, whereas low doping concentrations show very small signal gain compared to the optimized value.