Sains Malaysiana 30: 203-210 (2001)                                                                           Sains Fizis dan Gunaan /

                                                                                                                                                Physical and Applied Sciences

Effects of Double-Pass Superfluorescene on an

Erbium Doped Fibre Amplifier

M. A. Mahdi, S. Thirumeni, P. Poopalan, S. Selvakennedy

F. R. Mahmad Adikan H. Ahmad

Telekom Malaysia Photonics Research Center

Department of Physics, University of Malaya

50603 Kuala Lumpur, Malaysia

ABSTRACT

Effect of double-pass superfluorescence that clamps a population inversion of the fibre amplifier to have a fixed gain is presented. All optical gain­clamping in an erbium doped fibre amplifier is demonstrated using a broadband fibre Bragg grating that reflects the amplified spontaneous emission centred at 1530 nm with a 14 nm bandwidth. The proposed amplifier has an input dynamic range of -5 dBm in order to maintain the gain-clamping effect. Experiments on an eight-channel wavelength division multiplexing system shows that gain clamped at 21 dB. Gain flatness is less than 0.6 dB across all channels and gain variation is about 0.2 dB over the input signal power range.

ABSTRAK

Kesan lintasan-berganda superpendaflor yang mengehad songsangan populasi penguat gentian bagi membolehkan penguat mempunyai gandaan tetap dilaporkan. Pengehad-gandaan optik sepenuhnya pada penguat gentian berdop erbium telah dipraktikkan menggunakan gentian parutan Bragg berjalur lebar yang memantulkan pancaran spontan terganda yang berpusat pada panjang gelombang 1530 nm dengan lebar jalur 14 nm. Penguat yang dicadangkan mempunyai julat dinamik masukan -5 dBm untuk mengekalkan kesan pengehad-gandaan. Eksperimen ke atas sistem pemultipleks panjang gelombang terbahagi yang mempunyai lapan saluran menunjukkan gandaan terhad pada 2l dB. Kerataan gandaan adalah sekecil 0.6 dB ke atas kelapan­-lapan saluran dan variasi gandaan ialah 0.2 dB bagi seluruh julat kuasa isyarat masukan.

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