2 research outputs found
64Gb/s transmission over 57m MMF using an NRZ modulated 850nm VCSEL
We report a directly modulated 850nm VCSEL-based optical link operating error free (BER < 1E-12) at 64Gb/s over 57m of OM4 multimode fiber. At 60Gb/s, the error free distance increases to 107m
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μ κ°μ§λ©°, 87mW μ νμλ₯Ό μλΉνλ€.In this thesis, design of a maximum-eye-tracking CDR (MET-CDR) for minimum bit error rate (BER) is proposed. The proposed CDR does not require a BER coun-ter or an eye-opening monitor with any iterative procedure to find the near-optimal sampling phase. The biased data-level obtained from the weighted sum of error sampler outputs, UP and DN, extracts the actual eye height information in the presence of pre-cursor ISI. Two samplers operating on two slightly different tim-ings detect the current eye height and the polarity of the eye slope so that the CDR tracks the maximum eye height where the slope becomes zero. Measured results show that the sampling phase of the maximum eye height and that of the mini-mum BER match well. A prototype receiver fabricated in 28 nm CMOS process operates at 26 Gb/s with an eye-opening of 0.25 UI and consumes 87 mW while equalizing 23.5 dB of loss at 13 GHz.ABSTRACT I
CONTENTS II
LIST OF FIGURES IV
LIST OF TABLES VIII
CHAPTER 1 INTRODUCTION 1
1.1 MOTIVATION 1
1.2 THESIS ORGANIZATION 4
CHAPTER 2 BACKGROUNDS 5
2.1 RECEIVER FRONT-END 5
2.1.1 CHANNEL 7
2.1.2 EQUALIZER 17
2.1.3 CDR 32
2.2 PRIOR ARTS ON CLOCK RECOVERY 39
2.2.1 BB-CDR 39
2.2.2 BER-BASED CDR 41
2.2.3 EOM-BASED CDR 44
2.3 CONCEPT OF THE PROPOSED CDR 47
CHAPTER 3 MAXIMUM-EYE-TRACKING CDR WITH BIASED DATA-LEVEL AND EYE SLOPE DETECTOR 49
3.1 OVERVIEW 49
3.2 DESIGN OF MET-CDR 50
3.2.1 EYE HEIGHT INFORMATION FROM BIASED DATA-LEVEL 50
3.2.2 EYE SLOPE DETECTOR AND ADAPTATION ALGORITHM 60
3.2.3 ARCHITECTURE AND IMPLEMENTATION 67
3.2.4 VERIFICATION OF THE ALGORITHM 71
3.2.5 ANALYSIS ON THE BIASED DATA-LEVEL 76
3.3 EXPANSION OF MET-CDR TO PAM4 SIGNALING 84
3.3.1 MET-CDR WITH PAM4 84
3.3.2 CONSIDERATIONS FOR PAM4 87
CHAPTER 4 MEASUREMENT RESULTS 89
CHAPTER 5 CONCLUSION 99
APPENDIX A MATLAB CODE FOR SIMULATING RECEIVER WITH MET-CDR 100
BIBLIOGRAPHY 105
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