Title page
Abstract
Contents
I. INTRODUCTION 11
I.1 All-optical networks, the ultimate form of optical communication network 11
I.2 Gateway to all-optical wavelength conversions 12
I.2.1 Important role of all-optical wavelength converter 12
I.2.2 History of all-optical wavelength conversion's development 13
I.2.3 Multicast, multi-wavelength conversion and why all-optical multi-wavelength conversion using injection locking technique 15
I.3 Scope and outline of the thesis 16
II. THE ORETICAL BACKGROUND OF FP-LD WITH EXTERNAL OPTICAL INJECTION 17
II.1 Introduction 17
II.2 Injection-locking mechanism 18
II.3 The static properties of injection-locked laser output 22
III. OPERATION PRINCIPLE OF ALL-OPTICAL WAVELENGTH CONVERSION USING ABSORPTION MODULATION OF AN INJECTION-LOCKED FP-LD 25
III.1 Operation principle 25
III.2 All-optical multi-wavelength conversion 27
III.3 Optimal procedures to improve the performance of the multi-wavelength conversion 30
IV. EXPERIMENTAL SETUP AND RESULTS OF ALL-OPTICAL MULTI-WAVELENGTH CONVERSION 32
IV.1 Experimental setup 32
IV.2 Experimental results 34
V. CONCLUSION 43
References 45
Acknowledgements 50
Table II.1. Physical parameters of laser for the calculation of equation (2.12) 23
Fig. I.1 A bidirectional optical-electronic-optical converter consisting of a photodiode (PD), a trans-impedance amplifier (TIA), clock recovery and synthesis units (CRSU), a forward 14
Fig. II.1 Phasor diagram showing how the slave laser field β changes due to injection of field β₁from the master laser 20
Fig. II.2 Changes in gain g versus Δω for locked operation. Laser operation corresponds to the smallest value of g and is indicated by the solid line 21
Fig. II.3 Calculated increase in slave laser intensity versus detuning, where I=Ia+Ib is the total slave laser intensity, Ia is the amplified spontaneous emission, Ib is the amplified 24
Fig. III.1 (a) TM-mode absorption spectra of an FP-LD with (solid line) and without (dotted line) injection-locking by optical pump (b) an expanded view 26
Fig. III.2 Measured extinction ratios for converted 2.5Gbps outputs with different prove wavelengths for pump wavelength of 1566.12nm 29
Fig. IV.1 Experimental setup for the 2.5Gbps MWC, the number of channels can be added/dropped depending on the number of probe wavelengths 32
Fig. IV.2 Polarization beam splitter 33
Fig. IV.3 (a) Output spectra of the MWC, with (solid line) and without (dot line) input signals, when there are four channels. (b) Expanded view 35
Fig. IV.4 Eye diagrams, non-inverted waveforms, and inverted waveforms of back-to-back and 4 channels 37
Fig. IV.5 Eye diagrams of converted outputs of single wavelength conversion at 10 Gbps (a), (c) without CW holding beam, and (b), (d) with CW holding beam. Inlets in (b) 38
Fig. IV.6 Proposed experimental setup for the 10Gbps MWC 39
Fig. IV.7 BER measurement curves of each channel 40
Fig. IV.8 BER measurement curves of channel 1 when other channels are activated 42