Lecture 8 Fiber Optical Communication Lecture 8, Slide 1
|
|
- Randolf Wilcox
- 6 years ago
- Views:
Transcription
1 Lecture 8 Bit error rate The Q value Receiver sensitivity Sensitivity degradation Extinction ratio RIN Timing jitter Chirp Forward error correction Fiber Optical Communication Lecture 8, Slide
2 Bit error rate (4.6.) The bit error rate (BER) is the probability that a bit is incorrectly identified by the receiver (due to the noise and other signal distortion) A better name would be bit error probability A traditional requirement for optical receivers is BER < 0 9 The receiver sensitivity is the minimum averaged received optical power required to achieve the target BER Figure shows: A signal affected by noise The PDFs for the upper and lower current levels p (I) Probability density functions due to noise The decision threshold I D The dashed area indicates errors p 0 (I) Fiber Optical Communication Lecture 8, Slide
3 Agrawal defines: BER calculation p() is the probability to send a one P(0 ) is the probability to detect a sent out one as a zero p() p(0) / P(0 ) P( 0) BER p() P(0 ) p(0) P( 0) Assume that the noise has Gaussian statistics I (I 0 ) is the upper (lower) current level σ (σ 0 ) is the standard deviation of the upper (lower) level I D ( I I ) I I D P(0 ) exp di erfc P( 0) ( I I0) exp 0 di I erfc D 0 0 x I D erfc( x ) exp( y ) dy I 0 The erfc function Fiber Optical Communication Lecture 8, Slide 3
4 These expressions give us the BER BER calculation BER 4 erfc I I D erfc I D 0 I 0 BER using assumptions I 0 = 0, σ = σ 0 BER depends on I D Note: In general σ and σ 0 are not equal Example: Shot noise depends on the current σ > σ 0 since I > I 0 Fiber Optical Communication Lecture 8, Slide 4
5 Optimal decision threshold Minimize the BER using d(ber)/di D = 0 Optimal value is the intersection of the PDF for the one and zero levels Exact expression is given in the book Choosing I D according to expression below is a good approximation ( I I ) / ( I I ) Q D 0 0 D / I D 0I 0 I 0 Notice the definition of Q Often used as a measure of signal quality Thermal case: σ = σ 0 and I D = (I + I 0 )/ When shot noise cannot be neglected, I D shifts towards the zero level Fiber Optical Communication Lecture 8, Slide 5
6 The Q value The Q value is a measure of the eye opening since I I0 Q The optimum BER is related to the Q value as BER erfc If currents and noise levels are known, the BER can be found from Q 0 Q exp( Q / ) Q Q is often defined in db scale as Q ( in db) 0log0Q Example: BER = 0-9 corresponds to Q = 6 or 5.6 db Fiber Optical Communication Lecture 8, Slide 6
7 Minimum average received power (4.6.) Consider the following case: NRZ data in which zero bits contain no optical power, neglect dark current The receiver uses an APD, the p i n case is obtained by setting M = F A = The average current for a one is where the average received power is The Q value is Q where the shot noise is I I MR P MR P P rec MR P d rec / 0 ( s T ) s d ( P P0 ) / P qm F R (P ) f A d rec T d rec / and the thermal noise is The receiver sensitivity is then P rec T (4k T / R ) F f Q R d B qf A L Qf n T M Fiber Optical Communication Lecture 8, Slide 7
8 Minimum average received power When thermal noise dominates in a p i n receiver, we have ( Prec ) pin Q / R T d f This corresponds to SNR / 4 Example: Q = 6, R d = A/W, σ T = 0. μa P rec = 0.6 μw, SNR = 44 =.6 db I Q When shot noise dominates in a p i n receiver, we have ( P ) ( qf / Rd Q f rec ideal ) This corresponds to SNR I / Example: Q = 6 SNR = 36 = 5.6 db Q Fiber Optical Communication Lecture 8, Slide 8
9 Optimum sensitivity in APD receivers In a receiver dominated by thermal noise, an APD will increase the SNR There is an optimum gain, given by The corresponding sensitivity is / / T T k A ka Qqf k Qq f A M opt ( Prec ) APD (qf / Rd ) Q ( kamopt k Note: P rec Δf and not Δf as for thermally limited receivers For InGaAs APDs, the sensitivity is typically improved over a p i n diode receiver by 6 8 db A ) / Fiber Optical Communication Lecture 8, Slide 9
10 Quantum limit of photo detection (4.6.3) At very low power levels, the noise statistics are no longer Gaussian Denote the average number of photons per one bit by N p The probability of generating m electron-hole pairs is then given by the Poisson distribution m P exp( N ) N / m! Assume: No thermal noise, P 0 = 0, threshold is at one detected photon For BER < 0 9, we must have N p > 0 photons per one bit This corresponds to a power in a one of P = N p hνb and an average received power P rec = N p hνb/ Example: B = 0 Gbit/s, N p =0 P rec = 3 nw at λ = 550 nm m p P(0 ) P( 0) p( m 0) 0) exp( ) BER p N p Poisson distribution with N p = 5 Fiber Optical Communication Lecture 8, Slide 0
11 Receiver characterization Receivers are experimentally studied using a long pseudorandom binary sequence (PRBS) Random data is hard to generate Random data is not periodic Typical length 5 The BER is measured as a function of received average optical power Sensitivity = average power corresponding to a given BER (often 0 9 ) PRBS generator laser optical attenuator receiver under test PRBS detector transmitted sequence decided sequence XOR gate error counter Fiber Optical Communication Lecture 8, Slide
12 Sensitivity degradation So far, we have discussed an ideal situation Perfect pulses corrupted only by (inevitable) noise In reality, the receiver sensitivity is degraded There are additional sources of signal distortion The corresponding necessary increase in average received power to achieve a certain BER is called the power penalty Also without propagation in a fiber, a power penalty can arise Examples of degrading phenomena include: Limited modulator extinction ratio Transmitter intensity noise Timing jitter Fiber Optical Communication Lecture 8, Slide
13 Extinction ratio (4.7.) The extinction ratio (ER) is defined as r ex = P 0 /P P 0 (P ) is the emitted power in the off (on) state Ideally, r ex = 0 Different for direct and external modulation We use that The average received power is P rec = (P + P 0 )/ The definition of the Q-parameter is Q = (I I 0 )/(σ + σ 0 ) We find the sensitivity degradation to be r Q r ex ex Rd Prec 0 Fiber Optical Communication Lecture 8, Slide 3
14 Extinction ratio (ER), power penalty If thermal noise dominates, then σ = σ 0 = σ T, and the sensitivity is The power penalty is (in db) Prec ( rex ) ex log0 Prec (0) Laser biased below threshold r ex < 0.05 ( 3 db) δ ex < 0.4 db For a laser biased above threshold r ex > 0. δ ex >.5 db rec ( r The penalty is independent of Q and BER The penalty for APD receivers is larger than for p i n receivers P ex r ) r ex ex TQ Rd 0log 0 0 r r ex ex Fiber Optical Communication Lecture 8, Slide 4
15 Intensity noise (RIN) (4.7.) Intensity noise in LEDs and semiconductor lasers add to the thermal and shot noise Approximately, this is included by writing s T I where / I Rd Pin Rd Pinr r I RIN( I )d (The RIN spectrum was discussed earlier) The parameter r I is the inverse SNR of the transmitter Assuming zero extinction ratio and using that / s ( 4qR d Prec f ) I ri Rd P we can now write the Q-value as Q R P d rec / ( s T I ) T rec Fiber Optical Communication Lecture 8, Slide 5
16 Intensity noise (RIN), power penalty (4.7.3) The receiver sensitivity is found to be The power penalty is P rec Q T Q qf ( ri ) R ( r Q ) d I I 0log P ( r ) / P (0) 0log ( r ) 0 rec I rec 0 I Q BER Note that δ I when r I /Q The receiver cannot operate at the specified BER A BER floor BER Floors P rec Fiber Optical Communication Lecture 8, Slide 6
17 The recovered clock is based on the received, noisy signal The decision time fluctuates and causes timing jitter The data is not sampled at the bit slot center Leads to additional fluctuations of the signal entering the decision circuit In a thermally limited p i n receiver, we have Δi j is the current fluctuation σ j is the corresponding RMS value The penalty depends on the pulse shape, but for a typical case P rec( b) b / j 0log 0 0log0 Prec (0) ( b / ) b Q b = (4π /3 8)(Bτ j ) τ j is the RMS value of Δt Timing jitter Q I i j / ( T j ) / real decision times T 0 time optimal decision times Fiber Optical Communication Lecture 8, Slide 7
18 Timing jitter, power penalty The power penalty depends on Q (BER) The penalty will be higher at a lower BER Rule-of-thumb: The RMS value of the timing jitter should typically be smaller than 5 0% of the bit slot to avoid significant penalty Fiber Optical Communication Lecture 8, Slide 8
19 Real sensitivities are Receiver performance (4.8) 0 db above the quantum limit for APDs 5 db above the quantum limit for p i n diodes Mainly due to thermal noise Figure shows Measured sensitivities for p i n diodes (circles) and APDs (triangles) Lines show the quantum limit Two techniques to improve this Coherent detection Optical pre-amplification Both can reach sensitivities of only 5 db above the quantum limit Fiber Optical Communication Lecture 8, Slide 9
20 Loss-limited lightwave systems (5..) The maximum (unamplified) propagation distance is 0 P Lkm log f db/km P P rec is receiver sensitivity rec P tr is transmitter average power α f is the net loss of the fiber, splices, and connectors P rec and L are bit rate dependent Table shows wavelengths with corresponding quantum limits and typical losses tr Loss-limited transmission Transmitted power = mw λ = 850 nm, L max = 0 30 km λ =.55 µm, L max = km Fiber Optical Communication Lecture 8, Slide 0
21 Dispersion-limited lightwave systems (5..) Occurs when pulse broadening is more important than loss The dispersion-limited distance depends on for example The operating wavelength Since D is a function of λ The type of fiber Multi-mode: step-index or graded-index Single-mode: standard or dispersion-shifted Type of laser Longitudinal multimode Longitudinal singlemode large or small chirp λ = 850 nm, multimode SI-fiber Modal dispersion dominates Disp.-limited for B > 0.3 Mbit/s BL c n 0(Mbit/s) km λ = 850 nm, multimode GI-fiber Modal dispersion dominates Disp.-limited for B > 00 Mbit/s BL c n (Gbit/s) km Fiber Optical Communication Lecture 8, Slide
22 Dispersion-limited lightwave systems λ =.3 µm, SM-fiber, MM-laser Material dispersion dominates Disp.-limited for B > Gbit/s Using D σ λ = ps/nm 4 D 5(Gbit/s) km BL λ =.55 µm, SM-fiber, SM-laser B Material dispersion dominates Using D = 6 ps/(nm km) Disp.-limited for B > 5 Gbit/s L Gbit/s km λ =.55 µm, DS-fiber, SM-laser Material dispersion dominates Using D =.6 ps/(nm km) Disp.-limited for B > 5 Gbit/s B L Gbit/s km Long systems often use in-line amplifiers Loss is not a critical limitation Dispersion must be compensated for Noise and nonlinearities are important PMD can be a problem Fiber Optical Communication Lecture 8, Slide
23 System design (5..3) Part of the system design is to make sure the BER demand can be met The power budget is a very useful tool The transmitter average power (P tr ) and the average power required at the receiver (P rec ) are often specified P [dbm] tr P [dbm] rec [db] [db] C L M s C [db] L [db/km] f L [db] con [db] splice C L is the total channel loss (sum of fiber, connector, and splice losses) M s is the system margin (allowing penalties and degradation over time) Typically M s = 6 8 db A complete system is very complex and some of the parameters that must be considered are Modulation format, detection scheme, operating wavelength Transmitter and receiver implementation, type of fiber The trade-off between cost and performance The system reliability Fiber Optical Communication Lecture 8, Slide 3
24 Computer design tools To evaluate a complete system design, simulations are used VPItransmissionMaker is a commercial code for doing this Accurate modeling for many components but closed source = black box Fiber Optical Communication Lecture 8, Slide 4
25 VPItransmissionMaker Output will contain eye diagrams, spectra, BER etc. Fiber Optical Communication Lecture 8, Slide 5
26 Further sources of power penalty (5.4) The above mentioned power penalties were all due to the transmitter and the receiver Several more sources of power penalty appear during propagation Modal noise (in multi-mode fibers) Mode-partition noise (in multi-mode lasers) Intersymbol interference (ISI) due to pulse broadening Frequency chirp Reflection feedback All these involve dispersion Fiber Optical Communication Lecture 8, Slide 6
27 Power penalties in multi-mode fiber Modal noise Different modes interfere over the fiber cross-section Forms a time-varying speckle intensity pattern The received power will fluctuate Problem occurs with highly coherent sources To avoid this Use a single-mode fiber Reduce coherence Use a LED Mode-partition noise The power in each longitudinal mode of a multimode laser varies with time Output power is constant Different modes propagate at different velocities in a fiber Additional signal fluctuation is caused and the SNR is degraded Negligible penalty if BLDσ λ < 0. Fiber Optical Communication Lecture 8, Slide 7
28 Power penalty due to pulse broadening (5.4.4) Broadening affects the receiver in two ways Energy spreads beyond the bit slot ISI Pulse peak power is reduced for a given average received power Reduces the SNR Power penalty for Gaussian pulses assuming no ISI is 0 0log A d 0 0log0 0 A L Assuming β 3 C 0 and a large source spectral width, we have 0 LD 0 d 5log LD 0 / 0 Fiber Optical Communication Lecture 8, Slide 8
29 Power penalty due to pulse broadening Assuming β 3 C 0 and a small source spectral width, we have d 5log 0 L 0 Agrawal introduces the duty cycle A measure of the pulse width Defined as d c = 4 σ 0 /T B The penalty depends on Dispersion parameter Fiber length Bit rate Pulse width (duty cycle) Fiber Optical Communication Lecture 8, Slide 9
30 Power penalty due to chirp (5.4.5) Frequency chirping increases the impact of dispersion Occurs in directly modulated lasers Cannot modulate the amplitude without changing the phase Figure shows driving current, output power and wavelength of a directly modulated laser t c ps = chirp duration Δλ c = spectral shift associated with the chirp Exact impact is complicated Assume pulse is Gaussian with linear chirp Fiber Optical Communication Lecture 8, Slide 30
31 Power penalty due to chirp For chirped Gaussian pulses with β 3 0, we have c C L 0 5log0 L 0 A chirp-free pulse (C = 0) has negligible penalty when β B L < 0.05 Lasers have C = 4 to 8 giving δ c 4 6 db when β B L = 0.05 A negative penalty occurs if β C < 0 due to initial pulse compression Fiber Optical Communication Lecture 8, Slide 3
32 Eye-closure penalty (5.4.6) The eye is often used to monitor the signal quality The eye-closure penalty is eyeopening after transmission eye 0log0 eyeopening before transmission This definition is ambiguous since eye opening is not well defined NRZ CSRZ NRZ-DPSK RZ-DPSK 0 km eye opening 63 km Fiber Optical Communication Lecture 8, Slide 3
33 Forward error correction (FEC) (5.5) FEC can correct errors and reduce the BER Redundant data is introduced Decreases the effective bit rate... With given throughput, the bit rate increases...but BER is typically decreased by this operation Increases system complexity since encoders/decoders are needed Optical systems use simple FEC Symbol rate is very high, real-time processing is very difficult Reed-Solomon, RS(55, 39) is often used (gives 7% overhead) Coding gain is hereg c Q c is Q value when using FEC 0log0( Q / Q) Coding gain of 5 6 db is obtained with modest redundancy c Fiber Optical Communication Lecture 8, Slide 33
34 Optimum FEC The coding gain saturates with increasing redundancy There is an optimal redundancy depending on system parameters Figure shows simulated Q values before and after FEC decoding WDM system, 5 channels, 40 Gbit/s per channel FEC increases system reach considerably Fiber Optical Communication Lecture 8, Slide 34
Lecture 5 Fiber Optical Communication Lecture 5, Slide 1
Lecture 5 Bit error rate The Q value Receiver sensitivity Sensitivity degradation Extinction ratio RIN Timing jitter Chirp Forward error correction Fiber Optical Communication Lecture 5, Slide 1 Bit error
More informationChapter 8. Digital Links
Chapter 8 Digital Links Point-to-point Links Link Power Budget Rise-time Budget Power Penalties Dispersions Noise Content Photonic Digital Link Analysis & Design Point-to-Point Link Requirement: - Data
More information3. Design of single-channel IM/DD systems
3. Design of single-channel IM/DD systems Optical Communication Systems and Networks 2/38 BIBLIOGRAPHY Theory: Fiber-Optic Communications Systems Govind P. Agrawal, Chapter 5, Lightwave Systems, John Wiley
More informationBroadcast and distribution networks
4/7/06 SYSTEM ARCHITECTURES Point-to-point links Point-to-point links constitute the simplest kind of lightwave systems The link length can vary from less than a kilometer (short haul) to thousands of
More informationModule 12 : System Degradation and Power Penalty
Module 12 : System Degradation and Power Penalty Lecture : System Degradation and Power Penalty Objectives In this lecture you will learn the following Degradation during Propagation Modal Noise Dispersion
More informationUnit-5. Lecture -4. Power Penalties,
Unit-5 Lecture -4 Power Penalties, Power Penalties When any signal impairments are present, a lower optical power level arrives at the receiver compared to the ideal reception case. This lower power results
More informationOptical Digital Transmission Systems. Xavier Fernando ADROIT Lab Ryerson University
Optical Digital Transmission Systems Xavier Fernando ADROIT Lab Ryerson University Overview In this section we cover point-to-point digital transmission link design issues (Ch8): Link power budget calculations
More informationEXAMINATION FOR THE DEGREE OF B.E. and M.E. Semester
EXAMINATION FOR THE DEGREE OF B.E. and M.E. Semester 2 2009 101908 OPTICAL COMMUNICATION ENGINEERING (Elec Eng 4041) 105302 SPECIAL STUDIES IN MARINE ENGINEERING (Elec Eng 7072) Official Reading Time:
More informationUNIT - 6 ANALOG AND DIGITAL LINKS
UNIT - 6 ANALOG AND DIGITAL LINKS Analog links Introduction, overview of analog links, CNR, multichannel transmission techniques, RF over fiber, key link parameters, Radio over fiber links, microwave photonics.
More informationOFC SYSTEM: Design Considerations. BC Choudhary, Professor NITTTR, Sector 26, Chandigarh.
OFC SYSTEM: Design Considerations BC Choudhary, Professor NITTTR, Sector 26, Chandigarh. OFC point-to-point Link Transmitter Electrical to Optical Conversion Coupler Optical Fiber Coupler Optical to Electrical
More informationS Optical Networks Course Lecture 3: Modulation and Demodulation
S-72.3340 Optical Networks Course Lecture 3: Modulation and Demodulation Edward Mutafungwa Communications Laboratory, Helsinki University of Technology, P. O. Box 2300, FIN-02015 TKK, Finland Tel: +358
More informationECEN689: Special Topics in Optical Interconnects Circuits and Systems Spring 2016
ECEN689: Special Topics in Optical Interconnects Circuits and Systems Spring 016 Lecture 7: Transmitter Analysis Sam Palermo Analog & Mixed-Signal Center Texas A&M University Optical Modulation Techniques
More informationOptical Transport Tutorial
Optical Transport Tutorial 4 February 2015 2015 OpticalCloudInfra Proprietary 1 Content Optical Transport Basics Assessment of Optical Communication Quality Bit Error Rate and Q Factor Wavelength Division
More informationFiber Optic Communication Link Design
Fiber Optic Communication Link Design By Michael J. Fujita, S.K. Ramesh, PhD, Russell L. Tatro Abstract The fundamental building blocks of an optical fiber transmission link are the optical source, the
More informationAssessment of improvement of extension of reach of 10 Gbps PONs by using APDs
MS.C. DISSERTATION ON ELECTRICAL AND COMPUTER ENGINEERING, JULY 05 Assessment of improvement of extension of reach of 0 Gbps PONs by using APDs João A. R. Mourato Optical Communications and Photonics Group
More informationChapter 3 Signal Degradation in Optical Fibers
What about the loss in optical fiber? Why and to what degree do optical signals gets distorted as they propagate along a fiber? Fiber links are limited by in path length by attenuation and pulse distortion.
More informationTable 10.2 Sensitivity of asynchronous receivers. Modulation Format Bit-Error Rate N p. 1 2 FSK heterodyne. ASK heterodyne. exp( ηn p /2) 40 40
10.5. SENSITIVITY DEGRADATION 497 Table 10.2 Sensitivity of asynchronous receivers Modulation Format Bit-Error Rate N p N p ASK heterodyne 1 2 exp( ηn p /4) 80 40 FSK heterodyne 1 2 exp( ηn p /2) 40 40
More informationModule 10 : Receiver Noise and Bit Error Ratio
Module 10 : Receiver Noise and Bit Error Ratio Lecture : Receiver Noise and Bit Error Ratio Objectives In this lecture you will learn the following Receiver Noise and Bit Error Ratio Shot Noise Thermal
More informationAnalysis of Self Phase Modulation Fiber nonlinearity in Optical Transmission System with Dispersion
36 Analysis of Self Phase Modulation Fiber nonlinearity in Optical Transmission System with Dispersion Supreet Singh 1, Kulwinder Singh 2 1 Department of Electronics and Communication Engineering, Punjabi
More informationTechnical Feasibility of 4x25 Gb/s PMD for 40km at 1310nm using SOAs
Technical Feasibility of 4x25 Gb/s PMD for 40km at 1310nm using SOAs Ramón Gutiérrez-Castrejón RGutierrezC@ii.unam.mx Tel. +52 55 5623 3600 x8824 Universidad Nacional Autonoma de Mexico Introduction A
More informationFiber-Optic Communication Systems
Fiber-Optic Communication Systems Second Edition GOVIND P. AGRAWAL The Institute of Optics University of Rochester Rochester, NY A WILEY-iNTERSCIENCE PUBLICATION JOHN WILEY & SONS, INC. NEW YORK / CHICHESTER
More informationPerformance Limitations of WDM Optical Transmission System Due to Cross-Phase Modulation in Presence of Chromatic Dispersion
Performance Limitations of WDM Optical Transmission System Due to Cross-Phase Modulation in Presence of Chromatic Dispersion M. A. Khayer Azad and M. S. Islam Institute of Information and Communication
More informationOpto-electronic Receivers
Purpose of a Receiver The receiver fulfils the function of optoelectronic conversion of an input optical signal into an output electrical signal (data stream). The purpose is to recover the data transmitted
More informationOFC SYSTEM: Design & Analysis. BC Choudhary, Professor NITTTR, Sector 26, Chandigarh.
OFC SYSTEM: Design & Analysis BC Choudhary, Professor NITTTR, Sector 26, Chandigarh. OFC point-to-point Link Transmitter Electrical to Optical Conversion Coupler Optical Fiber Coupler Optical to Electrical
More informationLecture 3 Fiber Optical Communication Lecture 3, Slide 1
Lecture 3 Dispersion in single-mode fibers Material dispersion Waveguide dispersion Limitations from dispersion Propagation equations Gaussian pulse broadening Bit-rate limitations Fiber losses Fiber Optical
More informationFIBER OPTICS. Prof. R.K. Shevgaonkar. Department of Electrical Engineering. Indian Institute of Technology, Bombay. Lecture: 24. Optical Receivers-
FIBER OPTICS Prof. R.K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Lecture: 24 Optical Receivers- Receiver Sensitivity Degradation Fiber Optics, Prof. R.K.
More informationPhotonics and Optical Communication Spring 2005
Photonics and Optical Communication Spring 2005 Final Exam Instructor: Dr. Dietmar Knipp, Assistant Professor of Electrical Engineering Name: Mat. -Nr.: Guidelines: Duration of the Final Exam: 2 hour You
More informationLecture 7 Fiber Optical Communication Lecture 7, Slide 1
Dispersion management Lecture 7 Dispersion compensating fibers (DCF) Fiber Bragg gratings (FBG) Dispersion-equalizing filters Optical phase conjugation (OPC) Electronic dispersion compensation (EDC) Fiber
More informationOFC SYSTEMS Performance & Simulations. BC Choudhary NITTTR, Sector 26, Chandigarh
OFC SYSTEMS Performance & Simulations BC Choudhary NITTTR, Sector 26, Chandigarh High Capacity DWDM OFC Link Capacity of carrying enormous rates of information in THz 1.1 Tb/s over 150 km ; 55 wavelengths
More informationHigh Speed VCSEL Transmission at 1310 nm and 1550 nm Transmission Wavelengths
American Journal of Optics and Photonics 01; (): - http://www.sciencepublishinggroup.com/j/ajop doi: 10.11/j.ajop.0100.1 ISSN: 0- (Print); ISSN: 0- (Online) High Speed VCSEL Transmission at 110 nm and
More informationProject: IEEE P Working Group for Wireless Personal Area Networks N
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks N (WPANs( WPANs) Title: [VLC PHY Considerations] Date Submitted: [09 September 2008] Source: [Sang-Kyu Lim, Kang Tae-Gyu, Dae Ho
More informationUNIVERSITY OF TORONTO FACULTY OF APPLIED SCIENCE AND ENGINEERING. FINAL EXAMINATION, April 2017 DURATION: 2.5 hours
UNIVERSITY OF TORONTO FACULTY OF APPLIED SCIENCE AND ENGINEERING ECE4691-111 S - FINAL EXAMINATION, April 2017 DURATION: 2.5 hours Optical Communication and Networks Calculator Type: 2 Exam Type: X Examiner:
More informationOptical Fiber Technology. Photonic Network By Dr. M H Zaidi
Optical Fiber Technology Numerical Aperture (NA) What is numerical aperture (NA)? Numerical aperture is the measure of the light gathering ability of optical fiber The higher the NA, the larger the core
More informationπ code 0 Changchun,130000,China Key Laboratory of National Defense.Changchun,130000,China Keywords:DPSK; CSRZ; atmospheric channel
4th International Conference on Computer, Mechatronics, Control and Electronic Engineering (ICCMCEE 2015) Differential phase shift keying in the research on the effects of type pattern of space optical
More informationUNIT Write notes on broadening of pulse in the fiber dispersion?
UNIT 3 1. Write notes on broadening of pulse in the fiber dispersion? Ans: The dispersion of the transmitted optical signal causes distortion for both digital and analog transmission along optical fibers.
More informationTheoretical and Simulation Approaches for Studying Compensation Strategies of Nonlinear Effects Digital Lightwave Links Using DWDM Technology
Journal of Computer Science (11): 887-89, 007 ISSN 1549-66 007 Science Publications Theoretical and Simulation Approaches for Studying Compensation Strategies of Nonlinear Effects Digital Lightwave Links
More informationPhase Modulator for Higher Order Dispersion Compensation in Optical OFDM System
Phase Modulator for Higher Order Dispersion Compensation in Optical OFDM System Manpreet Singh 1, Karamjit Kaur 2 Student, University College of Engineering, Punjabi University, Patiala, India 1. Assistant
More informationPerformance Analysis Of Hybrid Optical OFDM System With High Order Dispersion Compensation
Performance Analysis Of Hybrid Optical OFDM System With High Order Dispersion Compensation Manpreet Singh Student, University College of Engineering, Punjabi University, Patiala, India. Abstract Orthogonal
More informationChirped Bragg Grating Dispersion Compensation in Dense Wavelength Division Multiplexing Optical Long-Haul Networks
363 Chirped Bragg Grating Dispersion Compensation in Dense Wavelength Division Multiplexing Optical Long-Haul Networks CHAOUI Fahd 3, HAJAJI Anas 1, AGHZOUT Otman 2,4, CHAKKOUR Mounia 3, EL YAKHLOUFI Mounir
More informationRZ BASED DISPERSION COMPENSATION TECHNIQUE IN DWDM SYSTEM FOR BROADBAND SPECTRUM
RZ BASED DISPERSION COMPENSATION TECHNIQUE IN DWDM SYSTEM FOR BROADBAND SPECTRUM Prof. Muthumani 1, Mr. Ayyanar 2 1 Professor and HOD, 2 UG Student, Department of Electronics and Communication Engineering,
More informationS Optical Networks Course Lecture 4: Transmission System Engineering
S-72.3340 Optical Networks Course Lecture 4: Transmission System Engineering Edward Mutafungwa Communications Laboratory, Helsinki University of Technology, P. O. Box 2300, FIN-02015 TKK, Finland Tel:
More informationfor SWL and LWL Fiber Systems Chromatic Dispersion Limited Link Lengths David Cunningham, Leonid Kazovsky* and M. Nowell
Chromatic Dispersion Limited Link Lengths for SWL and LWL Fiber Systems IEEE 802 Plenary Meeting Vancouver, BC November 11-15, 1996 David Cunningham, Leonid Kazovsky* and M. Nowell Hewlett-Packard Laboratories
More informationAll-Optical Signal Processing and Optical Regeneration
1/36 All-Optical Signal Processing and Optical Regeneration Govind P. Agrawal Institute of Optics University of Rochester Rochester, NY 14627 c 2007 G. P. Agrawal Outline Introduction Major Nonlinear Effects
More informationSection B Lecture 5 FIBER CHARACTERISTICS
Section B Lecture 5 FIBER CHARACTERISTICS Material absorption Losses Material absorption is a loss mechanism related to material composition and fabrication process for the fiber. This results in dissipation
More informationLightwave Systems. Chapter System Architectures Point-to-Point Links
Fiber-Optic Communications Systems, Third Edition. Govind P. Agrawal Copyright 2002 John Wiley & Sons, Inc. ISBNs: 0-471-21571-6 (Hardback); 0-471-22114-7 (Electronic) Chapter 5 Lightwave Systems The preceding
More informationLecture 4 Fiber Optical Communication Lecture 4, Slide 1
Lecture 4 Optical transmitters Photon processes in light matter interaction Lasers Lasing conditions The rate equations CW operation Modulation response Noise Light emitting diodes (LED) Power Modulation
More informationAnalysis of four channel CWDM Transceiver Modules based on Extinction Ratio and with the use of EDFA
Analysis of four channel CWDM Transceiver Modules based on Extinction Ratio and with the use of EDFA P.P. Hema [1], Prof. A.Sangeetha [2] School of Electronics Engineering [SENSE], VIT University, Vellore
More informationLecture 7 Fiber Optical Communication Lecture 7, Slide 1
Lecture 7 Optical receivers p i n ioes Avalanche ioes Receiver esign Receiver noise Shot noise Thermal noise Signal-to-noise ratio Fiber Optical Communication Lecture 7, Slie 1 Optical receivers The purpose
More informationLecture 6 Fiber Optical Communication Lecture 6, Slide 1
Lecture 6 Optical transmitters Photon processes in light matter interaction Lasers Lasing conditions The rate equations CW operation Modulation response Noise Light emitting diodes (LED) Power Modulation
More informationUNIT-II : SIGNAL DEGRADATION IN OPTICAL FIBERS
UNIT-II : SIGNAL DEGRADATION IN OPTICAL FIBERS The Signal Transmitting through the fiber is degraded by two mechanisms. i) Attenuation ii) Dispersion Both are important to determine the transmission characteristics
More informationFigure Figure E E-09. Dark Current (A) 1.
OSI Optoelectronics, is a leading manufacturer of fiber optic components for communication systems. The products offer range for Silicon, GaAs and InGaAs to full turnkey solutions. Photodiodes are semiconductor
More informationDynamic Behavior of Mode Partition Noise in MMF. Petar Pepeljugoski IBM Research
Dynamic Behavior of Mode Partition Noise in MMF Petar Pepeljugoski IBM Research 1 Motivation and Issues Inconsistent treatment of mode partition noise (MPN) and relative intensity noise (RIN) in spreadsheet
More informationLecture 2 Fiber Optical Communication Lecture 2, Slide 1
Lecture 2 General concepts Digital modulation in general Optical modulation Direct modulation External modulation Modulation formats Differential detection Coherent detection Fiber Optical Communication
More informationPerformance Analysis of WDM-FSO Link under Turbulence Channel
Available online at www.worldscientificnews.com WSN 50 (2016) 160-173 EISSN 2392-2192 Performance Analysis of WDM-FSO Link under Turbulence Channel Mazin Ali A. Ali Department of Physics, College of Science,
More informationPerformance of Digital Optical Communication Link: Effect of In-Line EDFA Parameters
PCS-7 766 CSDSP 00 Performance of Digital Optical Communication Link: Effect of n-line EDFA Parameters Ahmed A. Elkomy, Moustafa H. Aly, Member of SOA, W. P. g 3, Senior Member, EEE, Z. Ghassemlooy 3,
More informationComment Supporting materials: The Reuse of 10GbE SRS Test for SR4/10, 40G-LR4. Frank Chang Vitesse
Comment Supporting materials: The Reuse of 10GbE SRS Test for SR4/10, 40G-LR4 Frank Chang Vitesse Review 10GbE 802.3ae testing standards 10GbE optical tests and specifications divided into Transmitter;
More informationOptimisation of DSF and SOA based Phase Conjugators. by Incorporating Noise-Suppressing Fibre Gratings
Optimisation of DSF and SOA based Phase Conjugators by Incorporating Noise-Suppressing Fibre Gratings Paper no: 1471 S. Y. Set, H. Geiger, R. I. Laming, M. J. Cole and L. Reekie Optoelectronics Research
More informationS Transmission Methods in Telecommunication Systems (5 cr) Tutorial 4/2007 (Lectures 6 and 7)
S-7.1140 Transmission Methods in Telecommunication Systems (5 cr) Tutorial 4/007 (Lectures 6 and 7) 1 1. Line Codes / Johtokoodit Sketch beneath each other line codes Manchester, Differential Manchester
More informationPerformance Evaluation of 32 Channel DWDM System Using Dispersion Compensation Unit at Different Bit Rates
Performance Evaluation of 32 Channel DWDM System Using Dispersion Compensation Unit at Different Bit Rates Simarpreet Kaur Gill 1, Gurinder Kaur 2 1Mtech Student, ECE Department, Rayat- Bahra University,
More informationEENG473 Mobile Communications Module 3 : Week # (12) Mobile Radio Propagation: Small-Scale Path Loss
EENG473 Mobile Communications Module 3 : Week # (12) Mobile Radio Propagation: Small-Scale Path Loss Introduction Small-scale fading is used to describe the rapid fluctuation of the amplitude of a radio
More informationOptical Fibre Amplifiers Continued
1 Optical Fibre Amplifiers Continued Stavros Iezekiel Department of Electrical and Computer Engineering University of Cyprus ECE 445 Lecture 09 Fall Semester 2016 2 ERBIUM-DOPED FIBRE AMPLIFIERS BASIC
More informationS Optical Networks Course Lecture 2: Essential Building Blocks
S-72.3340 Optical Networks Course Lecture 2: Essential Building Blocks Edward Mutafungwa Communications Laboratory, Helsinki University of Technology, P. O. Box 2300, FIN-02015 TKK, Finland Tel: +358 9
More informationCHAPTER 4 RESULTS. 4.1 Introduction
CHAPTER 4 RESULTS 4.1 Introduction In this chapter focus are given more on WDM system. The results which are obtained mainly from the simulation work are presented. In simulation analysis, the study will
More informationTemporal phase mask encrypted optical steganography carried by amplified spontaneous emission noise
Temporal phase mask encrypted optical steganography carried by amplified spontaneous emission noise Ben Wu, * Zhenxing Wang, Bhavin J. Shastri, Matthew P. Chang, Nicholas A. Frost, and Paul R. Prucnal
More informationPerformance Analysis of Chromatic Dispersion Compensation of a Chirped Fiber Grating on a Differential Phase-shift-keyed Transmission
Journal of the Optical Society of Korea Vol. 13, No. 1, March 2009, pp. 107-111 DOI: 10.3807/JOSK.2009.13.1.107 Performance Analysis of Chromatic Dispersion Compensation of a Chirped Fiber Grating on a
More information11.1 Gbit/s Pluggable Small Form Factor DWDM Optical Transceiver Module
INFORMATION & COMMUNICATIONS 11.1 Gbit/s Pluggable Small Form Factor DWDM Transceiver Module Yoji SHIMADA*, Shingo INOUE, Shimako ANZAI, Hiroshi KAWAMURA, Shogo AMARI and Kenji OTOBE We have developed
More informationFigure Responsivity (A/W) Figure E E-09.
OSI Optoelectronics, is a leading manufacturer of fiber optic components for communication systems. The products offer range for Silicon, GaAs and InGaAs to full turnkey solutions. Photodiodes are semiconductor
More informationMuhammad Ali Jinnah University, Islamabad Campus, Pakistan. Fading Channel. Base Station
Fading Lecturer: Assoc. Prof. Dr. Noor M Khan Department of Electronic Engineering, Muhammad Ali Jinnah University, Islamabad Campus, Islamabad, PAKISTAN Ph: +9 (51) 111-878787, Ext. 19 (Office), 186 (ARWiC
More informationDynamic Behavior of Mode Partition Noise in MMF. Petar Pepeljugoski IBM Research
Dynamic Behavior of Mode Partition Noise in MMF Petar Pepeljugoski IBM Research 1 Motivation and Issues Inconsistent treatment of mode partition noise (MPN) and relative intensity noise (RIN) in spreadsheet
More information1300nm Fast Ethernet Transceiverin1x9SC Duplex Package
1300nm Fast Ethernet Transceiverin1x9SC Duplex Package OPF5102 Technical Data Features 1310nm LED Data Rate: 155Mbps, NRZ Single +3.3V Power Supply PECL Differential Electrical Interface Industry Standard
More informationThe electric field for the wave sketched in Fig. 3-1 can be written as
ELECTROMAGNETIC WAVES Light consists of an electric field and a magnetic field that oscillate at very high rates, of the order of 10 14 Hz. These fields travel in wavelike fashion at very high speeds.
More informationEfficiency of complex modulation methods in coherent free-space optical links
Efficiency of complex modulation methods in coherent free-space optical links Aniceto Belmonte 1,* and Joseph M. Kahn 1 Technical University of Catalonia, Department of Signal Theory and Communications,
More informationLecture 5 Transmission
Lecture 5 Transmission David Andersen Department of Computer Science Carnegie Mellon University 15-441 Networking, Spring 2005 http://www.cs.cmu.edu/~srini/15-441/s05 1 Physical and Datalink Layers: 3
More informationFIBER OPTICS. Prof. R.K. Shevgaonkar. Department of Electrical Engineering. Indian Institute of Technology, Bombay. Lecture: 22.
FIBER OPTICS Prof. R.K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Lecture: 22 Optical Receivers Fiber Optics, Prof. R.K. Shevgaonkar, Dept. of Electrical Engineering,
More informationCompensation of Dispersion in 10 Gbps WDM System by Using Fiber Bragg Grating
International Journal of Computational Engineering & Management, Vol. 15 Issue 5, September 2012 www..org 16 Compensation of Dispersion in 10 Gbps WDM System by Using Fiber Bragg Grating P. K. Raghav 1,
More informationOptical Amplifiers (Chapter 6)
Optical Amplifiers (Chapter 6) General optical amplifier theory Semiconductor Optical Amplifier (SOA) Raman Amplifiers Erbium-doped Fiber Amplifiers (EDFA) Read Chapter 6, pp. 226-266 Loss & dispersion
More informationLecture 5 Transmission. Physical and Datalink Layers: 3 Lectures
Lecture 5 Transmission Peter Steenkiste School of Computer Science Department of Electrical and Computer Engineering Carnegie Mellon University 15-441 Networking, Spring 2004 http://www.cs.cmu.edu/~prs/15-441
More information10 Gb/s transmission over 5 km at 850 nm using single-mode photonic crystal fiber, single-mode VCSEL, and Si-APD
10 Gb/s transmission over 5 km at 850 nm using single-mode photonic crystal fiber, single-mode VCSEL, and Si-APD Hideaki Hasegawa a), Yosuke Oikawa, Masato Yoshida, Toshihiko Hirooka, and Masataka Nakazawa
More informationSHF Communication Technologies AG
SHF Communication Technologies AG Wilhelm-von-Siemens-Str. 23 Aufgang D 12277 Berlin Marienfelde Germany Phone ++49 30 / 772 05 10 Fax ++49 30 / 753 10 78 E-Mail: sales@shf.biz Web: http://www.shf.biz
More informationNotes on Optical Amplifiers
Notes on Optical Amplifiers Optical amplifiers typically use energy transitions such as those in atomic media or electron/hole recombination in semiconductors. In optical amplifiers that use semiconductor
More informationOptical Wireless Communications
Optical Wireless Communications System and Channel Modelling with MATLAB Z. Ghassemlooy W. Popoola S. Rajbhandari W CRC Press Taylor & Francis Croup Boca Raton London New York CRC Press is an imprint of
More informationPublic Progress Report 2
Embedded Resonant and ModulablE Self- Tuning Laser Cavity for Next Generation Access Network Transmitter ERMES Public Progress Report 2 Project Project acronym: ERMES Project full title: Embedded Resonant
More informationVisible to infrared high-speed WDM transmission over PCF
Visible to infrared high-speed WDM transmission over PCF Koji Ieda a), Kenji Kurokawa, Katsusuke Tajima, and Kazuhide Nakajima NTT Access Network Service Systems Laboratories, NTT Corporation, 1 7 1 Hanabatake,
More informationCoherent Lightwave Systems
Fiber-Optic Communications Systems, Third Edition. Govind P. Agrawal Copyright 2002 John Wiley & Sons, Inc. ISBNs: 0-471-21571-6 (Hardback); 0-471-22114-7 (Electronic) Chapter 10 Coherent Lightwave Systems
More informationComparison between DWDM Transmission Systems over SMF and NZDSF with 25 40Gb/s signals and 50GHz Channel Spacing
Comparison between DWDM Transmission Systems over SMF and NZDSF with 25 4Gb/s signals and 5GHz Channel Spacing Ruben Luís, Daniel Fonseca, Adolfo V. T. Cartaxo Abstract The use of new types of fibre with
More informationInvestigate the characteristics of PIN Photodiodes and understand the usage of the Lightwave Analyzer component.
PIN Photodiode 1 OBJECTIVE Investigate the characteristics of PIN Photodiodes and understand the usage of the Lightwave Analyzer component. 2 PRE-LAB In a similar way photons can be generated in a semiconductor,
More informationAvailable online at
Available online at www.sciencedirect.com Optics Communications 281 (2008) 3495 3500 www.elsevier.com/locate/optcom Analysis and simulation of the effect of spectral width over intensity noise under the
More informationLecture 10. Dielectric Waveguides and Optical Fibers
Lecture 10 Dielectric Waveguides and Optical Fibers Slab Waveguide, Modes, V-Number Modal, Material, and Waveguide Dispersions Step-Index Fiber, Multimode and Single Mode Fibers Numerical Aperture, Coupling
More informationPerformance Evaluation of Gbps (1.28 Tbps) FSO Link using RZ and NRZ Line Codes
Performance Evaluation of 32 40 Gbps (1.28 Tbps) FSO Link using RZ and NRZ Line Codes Jasvir Singh Assistant Professor EC Department ITM Universe, Vadodara Pushpa Gilawat Balkrishna Shah Assistant Professor
More informationARTICLE IN PRESS. Optik 119 (2008)
Optik 119 (28) 39 314 Optik Optics www.elsevier.de/ijleo Timing jitter dependence on data format for ideal dispersion compensated 1 Gbps optical communication systems Manjit Singh a, Ajay K. Sharma b,,
More informationDetectors for Optical Communications
Optical Communications: Circuits, Systems and Devices Chapter 3: Optical Devices for Optical Communications lecturer: Dr. Ali Fotowat Ahmady Sep 2012 Sharif University of Technology 1 Photo All detectors
More informationLecture 9 External Modulators and Detectors
Optical Fibres and Telecommunications Lecture 9 External Modulators and Detectors Introduction Where are we? A look at some real laser diodes. External modulators Mach-Zender Electro-absorption modulators
More informationWHITE PAPER LINK LOSS BUDGET ANALYSIS TAP APPLICATION NOTE LINK LOSS BUDGET ANALYSIS
TAP APPLICATION NOTE LINK LOSS BUDGET ANALYSIS WHITE PAPER JULY 2017 1 Table of Contents Basic Information... 3 Link Loss Budget Analysis... 3 Singlemode vs. Multimode... 3 Dispersion vs. Attenuation...
More informationPerformance Investigation of RAMAN-EDFA HOA for DWDM System (Received 17 September, 2016 Accepted 02 October, 2016)
Performance Investigation of RAMAN-EDFA HOA for DWDM System (Received 17 September, 2016 Accepted 02 October, 2016) ABSTRACT Neha Thakral Research Scholar, DAVIET, Jalandhar nthakral9@gmail.com Earlier
More informationSatellite Communications: Part 4 Signal Distortions & Errors and their Relation to Communication Channel Specifications. Howard Hausman April 1, 2010
Satellite Communications: Part 4 Signal Distortions & Errors and their Relation to Communication Channel Specifications Howard Hausman April 1, 2010 Satellite Communications: Part 4 Signal Distortions
More informationSIMULATIVE INVESTIGATION OF SINGLE-TONE ROF SYSTEM USING VARIOUS DUOBINARY MODULATION FORMATS
SIMULATIVE INVESTIGATION OF SINGLE-TONE ROF SYSTEM USING VARIOUS DUOBINARY MODULATION FORMATS Namita Kathpal 1 and Amit Kumar Garg 2 1,2 Department of Electronics & Communication Engineering, Deenbandhu
More informationElectronic equalization for enabling communications at OC-192 rates using OC-48 components
Electronic equalization for enabling communications at OC-192 rates using OC-48 components G. S. Kanter, A. K. Samal, O. Coskun and A. Gandhi Santel Networks, 39899 Balentine Drive, Suite 350, Newark,
More informationUltra-long Span Repeaterless Transmission System Technologies
Ultra-long Span Repeaterless Transmission System Technologies INADA Yoshihisa Abstract The recent increased traffic accompanying the rapid dissemination of broadband communications has been increasing
More informationError Probability Estimation for Coherent Optical PDM-QPSK Communications Systems
Error Probability Estimation for Coherent Optical PDM-QPSK Communications Systems Xianming Zhu a, Ioannis Roudas a,b, John C. Cartledge c a Science&Technology, Corning Incorporated, Corning, NY, 14831,
More informationPerformance of OCDMA Systems Using Random Diagonal Code for Different Decoders Architecture Schemes
The International Arab Journal of Information Technology, Vol. 7, No. 1, January 010 1 Performance of OCDMA Systems Using Random Diagonal Code for Different Decoders Architecture Schemes Hilal Fadhil,
More information