Performance analysis on double-pass thulium-doped fiber amplifier for 16-channel WDM system at S-band

Abstract

Abstract In this paper, the performance of single and double-pass thulium-doped fiber amplifiers (SD-TDFA and DP-TDFA) is analyzed in the short wavelength (S-band) region. The effect of thulium-doped fiber (TDF) length, input signal power, and input pumping power on the amplifier’s performance is comprehensively investigated on basis of gain and noise figure (NF). DP-TDFA showed a higher gain compared to single-pass configuration and that is due to double-propagation of the forwarded and amplified spontaneous emission (ASE) signal into the TDF which maximizes the achievable gain in the S-band region. At a gain medium length of 8 m, the proposed DP-TDFA showed higher gain enhancement over SP-TDFA at an input power of −20 dB compared to −40 and 0 dB input signal powers. The gain enhancement at 1470 nm is 5.6 dB, while the maximum recorded gain with the proposed double-pass configuration is 14.7 dB.