International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 64...
Upcoming SlideShare
Loading in...5
×

20120140503003

122

Published on

Published in: Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
122
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
1
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "20120140503003"

  1. 1. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 21 WDM TRANSMISSION IN L-BAND OVER CONVENTIONAL SINGLE MODE FIBER WITH 27.2-dB SPAN LOSS CONSIDERING NON- LINEARITIES AND ASE NOISE Niyati A. Maniar, Rohit B. Patel Dept. of Electronics & Communication Engineering, Ganpat University, Kherva, India ABSTRACT We have report the transmission of twenty 10-Gb/s channels and twenty 20-Gb/s with 100- GHz spacing over 80 km spans of Conventional single mode fiber in the lower wavelength region of L-band. Low error rates are achieved with 2.5 dBm input power per channel and a span loss of 27.2 dB. For large transmission distances it covers 320 km for 400-Gb/s and 720 km for 200-Gb/s with acceptable bit error rate using pre and post-dispersion compensation technique. It was also observed that post compensation provides better performance compare to pre-compensation method. Keywords: BER, Conventional Single Mode Fiber, Dispersion Compensation, Q-Factor, Wavelength Division Multiplexing. I. INTRODUCTION Optical fibers are used for data transmission in optical fiber communication system. In optical fiber data flows in form of light. Recently, the traffic over transmission lines has increased rapidly. With a view of enlarging the transmission line capacity, increasing attention has been directed toward wavelength-division multiplexing (WDM) techniques and higher bit-rate transmissions of more than 40-Gb/s. Wavelength division multiplexing (WDM) can give two benefits at the same time: enhancement of transmission capacity and increase in flexibility in optical network design [1]. It is possible to build long-distance transparent optical transmission links without electrical regenerators with the help of erbium-doped fiber amplifiers (EDFAs). EDFA plays an important role to avoid the losses in the signal. EDFA has been used as booster and inline amplifier to transmit optical signals over thousands of kilometers. EDFAs are having of low noise figure and have a good gain bandwidth and can amplify multichannel signals on different wavelengths simultaneously, so EDFA emerges as the implementing technology for WDM systems [2]. Although the use of optical INTERNATIONAL JOURNAL OF ADVANCED RESEARCH IN ENGINEERING AND TECHNOLOGY (IJARET) ISSN 0976 - 6480 (Print) ISSN 0976 - 6499 (Online) Volume 5, Issue 3, March (2014), pp. 21-36 © IAEME: www.iaeme.com/ijaret.asp Journal Impact Factor (2014): 7.8273 (Calculated by GISI) www.jifactor.com IJARET © I A E M E
  2. 2. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 22 amplifiers has extended the optical network dimensions to thousands of kilometers and made the concept of transparent optical networks quite feasible, at the same time their use introduces some problems like accumulation of amplified spontaneous emission (ASE) noise generated by inline optical amplifiers and aggravation of fiber nonlinearity effects such as stimulated Raman scattering (SRS) and four-wave mixing (FWM). In such systems, apart from the usual problems of fiber loss (amplifier noise) and dispersion, fiber nonlinearities are likely to impose a transmission limit due to the increased total interaction length [3].System specifications such as total transmission distance, amplifier spacing, the number of WDM channels, the channel spacing and the power per channel are all affected by the fiber nonlinear effects. The performance of optical fiber is limited by the factor known as dispersion. When optical signals are transmitted over optical links, different wavelength components of the optical signals will generally experience different propagation times due to the fact that the transport medium (such as an optical fiber) has different effective refractive indices for different wavelengths. This phenomenon is referred to as dispersion, or chromatic dispersion. As a result of dispersion, an optical pulse, which always has some finite width in wavelength, will be broadened, since different wavelength components of the pulse will travel at slightly different group velocities through the optical link. Such broadening of optical pulses caused by the dispersion may lead to a situation at the receiver end where it is difficult to separate adjacent pulses from each other during detection which leads to errors in receiver and correct reception of bits. Moreover, dispersion compensation over a wide wavelength range is particularly needed for WDM transmissions. Dispersion-shifted fibers, dispersion-flattened fibers, dispersion decreasing fibers, DCFs (dispersion compensating fiber) are used for dispersion compensation in optical communication system. DCF is the type of fiber that has the opposite dispersion (negative dispersion) of the fiber (positive dispersion) being used in a transmission system. It is used to nullify the positive dispersion of the fiber [4, 5]. Particularly for high modulation rate systems, dispersion becomes a severely limiting factor. The transmission impairment caused by dispersion in a single mode fiber (SMF) is severe for such high-bit-rate transmissions. For this reason, it is typically required to use some kind of dispersion compensation along the optical link and/or at the receiver side. This has made dispersion-compensation techniques essential, and a dispersion- compensation fiber (DCF) is widely used. Various DCFs that were optimized to compensate for the dispersion in a single band, e.g., the S-band (1460–1530 nm), C-band (1530–1565 nm), and L-band (1565–1625 nm), have been reported, and they were obtained by matching the relative dispersion to slope (RDS) of the DCF to that of the transmission fiber. It has also been reported that combining two or more DCFs can realize broadband compensation from the C-band to the L-band. However, it is difficult for the DCF to compensate for dispersion over the O-band (1260–1360 nm) or the E-band (1360–1460 nm). This is because the material dispersion has a strong effect. It is therefore difficult to control the dispersion over all the telecommunication bands [6].The maximum possible transmission distance depends on various system parameters like number of channels, channel spacing, allowable power per channel, amplifier spacing, etc. With Reference to paper [7], reported the transmission of twenty 10-Gbps channels with 100-GHz spacing over four 80-km spans of dispersion-shifted fiber in the lower wavelength region of L-band. They have used dispersion shifted fiber with core size of 50 µm^2 with pre-dcf compensation technique. The loss per Span was kept 25 dB. The BER obtained was <10^ (-12) for 200-Gb/s. In this letter, we report low error rate transmission <10^(-15) of twenty 10-Gb/s and <10^(-12) 0f twenty 20-Gb/s channels with 100-GHz spacing over 80 km spans of conventional single mode fiber having core size of 80 µm^2, each with a span loss of 27.2 dB using pre and post compensation. Also, non-linearities effect and ASE noise is considered. We choose operation in the lower wavelength region of the L-band.
  3. 3. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 23 II. DATA MODULATION FORMAT An optical modulation format is the method used to impress data (i.e., information) on an optical carrier wave for transmission over optical fiber or any other any other media such as free space, nano photonic optical waveguide, etc. In conventional single mode optical fibers, the optical field has three physical attributes that can be used to carry information: intensity, phase (or frequency) and polarization. Depending upon which of the three quantitative is used for information transport, we distinguish between intensity, phase (or frequency) and polarization data modulation formats. This classification does not require a phase modulated optical field to be constant envelope, nor an intensity modulated field to have constant phase. It is the physical quantity used to convey data information that drives the classification. The simplest optical modulation format is on-off keying (OOK) intensity modulation, which can take either of two forms: non return to zero (NRZ) or return Zero (RZ).We have used NRZ format. The advantages of using NRZ data modulation formats include its low electrical bandwidth requirement, insensitivity to laser phase noise and simplest configuration of transceivers. The reduced spectrum width improves the dispersion tolerance. In the NRZ format the function that describes the voltage pulse is given by [8]: V(t)=Von-off [1-exp(-t/trise)^2] Vm=Von V(t)=Von-off[exp(-t/trise)^2] Vm=Voff Where Von-off=Von-Voff= -2mVbias and trise is the circuit rise time that determines the 3dB modulation bandwidth BW. III. SIMULATION SET-UP The schematic block diagram of the proposed 20-channel 10-Gb/s and 20-Gb/s WDM link using pre and post and compensation technique is shown in Fig.1 respectively. The dispersion compensation is done using pre and post-compensation techniques depending on the position of Dispersion Compensating Fiber (DCF). Pre-Compensation: In this Compensation scheme, the dispersion compensating fiber of negative dispersion is placed before the standard fiber to compensate positive dispersion of the standard fiber. Post-Compensation: In this Compensation scheme, the dispersion compensating fiber of negative dispersion is placed after the standard fiber to compensate positive dispersion of the standard fiber [5, 6, 9]. The WDM transmitter consists of 20 channels which is spaced by 100 GHz from 1574.6 to 1590.31 nm using CW laser and are combined using Wavelength Division Multiplexer (WDM). The modulation format used is Non Return to Zero (NRZ). The power per channel launched at the start of every span was 2.5 dBm which was found optimum for minimum effect of non-linearities. One span of link consists of conventional single mode fiber, EDFA and dispersion compensating fiber. A 80 km SMF which has a dispersion of 17ps/nm/km would encounter a total of (80 x 17) 1360ps/nm of dispersion. Assuming the DCF has a negative dispersion of -85 ps/nm/km, and then 16km (1360ps/nm ÷ 85ps/nm/km) of DCF is needed for the compensation. A matched-cladding type DCF has a positive dispersion slope similar to transmission fibers and the dispersion slope of the DCF is steeper than that of the conventional single-mode fiber [5]. When this type of DCF is used for dispersion compensation, the dispersion slope for the whole transmission system including the DCF becomes larger than that for the transmission fiber alone and a wavelength region where the dispersion is well compensated is restricted to a narrow range. The gain of the erbium doped fiber amplifier (EDFA) placed after each fiber is such that is compensates the losses of the preceding fiber. The noise figure of the amplifiers is constant and set to 4 dB. The Overall loss for each span is 27.2 dB including dispersion
  4. 4. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 24 compensator loss. The non-linearities effect of conventional single mode fiber and ASE noise of EDFA is also taken in to account. The simulation parameters and fiber parameters used in the system model are mentioned in Table 1. The channels at the receiver side are demultiplexed using Demultiplexer. At the end of the link the channels are detected with a p-i-n receiver and low pass Bessel filter with order two is used. The dark current and responsivity of the PIN diode is taken as 10 nA and 1 A/W respectively. 3R regenerator is used to generate an electrical signal, connected directly to the BER analyzer which is used to visualize the graphs and results such as eye diagram, eye opening, the Q value and BER. The experiment is carried out for two different data rates (a) Each channel is modulated at 10-Gb/s, so total data rate is 200-Gb/s. (b) Each channel is modulated at 20-Gb/s, so total data rate is 400-Gb/s. (a) (b) Fig.1: Schematic of simulation setups: (a) using pre-compensation (b) using post-compensation
  5. 5. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 25 IV. RESULTS For 200 Gb/s and 400 Gb/s, the simulation was carried out for pre and post-compensation. The result was compared in terms of Q value, BER and eye-diagram. Q-factor can be defined as ratio of Signal to Noise Ratio (SNR) versus transmission distance per symbol. The bit error rate (BER) is the percentage of bits that have errors relative to the total number of bits received in a transmission, usually expressed as ten to a negative power. Eye diagram is used to visualize how the waveforms used to send multiple bits of data can potentially lead to errors in the interpretation of those bits. This is the so-called problem of intersymbol interference. It was found that post compensation performed better than pre-compensation technique. The total distance covered is 720(9X80) for 200-Gbps and 320km (4X80) for 400-Gbps considering only conventional single mode fiber. The Q versus wavelength for all twenty channels wavelength for 200-Gb/s using pre-compensation and post- compensation method is plotted in Fig.2 respectively. The measured BER versus wavelength for all twenty channels for 200-Gb/s using pre-compensation and post-compensation method are plotted in Fig.3 respectively. TABLE 1: Parameters used in simulation Parameter Value Total Channels 20 Bit-Rate 200,400 Gb/s Channel Spacing 100-GHz Length of SMF 80 Km Length of DCF 16 Km Dispersion coefficient of SMF 17 ps/nm/km Dispersion coefficient of DCF -85 ps/nm/km Gain of Inline EDFA for SMF 24 db Gain of Inline EDFA for DCF 3.2db Attenuation factor of SMF 0.2 db/km Total Span 9 for 200-Gbps,4 for 400-Gbps Total Distance covered 720 for 200-Gbps 320 km for 400-Gbps The Q versus wavelength for all twenty channels wavelength for 400 Gb/s using pre- compensation and post-compensation method are plotted in Fig.4 respectively. The measured BER versus wavelength for all twenty channels for 400-Gb/s using pre-compensation and post- compensation method are plotted in Fig.5 respectively. The Bold letters in the table indicates the improvement of wavelength in terms of Q-factor and BER for post- compensation scheme over pre- compensation scheme. It was found that, for 200- Gb/s, for wavelength 1574.6 nm, Q-factor for pre- compensation is 11.84 and BER is 1E-32 and for post-compensation Q-factor is 15.08 and BER is 1.02E-51 respectively. Similarly, for 400-Gb/s for wavelengths 1574.6 nm, Q-factor for pre- compensation is 7.19 and BER is 2.56E-13 and for post-compensation Q factor is 8.09 and BER is 2.7E-16. The table and graph clearly indicates the post scheme performs significantly better than pre- scheme compensation. The performance of the lower wavelength channels is seen to be lesser than that of the longer wavelength channels. This is likely due to a combination of larger FWM and CPM, together with some overcompensation of dispersion. Comparison between pre and post-scheme in terms of Q factor and BER for 200-Gb/s and 400-Gb/s is given in Table 2 and 3 respectively.
  6. 6. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 26 TABLE 2: Comparison between pre and post-compensation scheme for 200-Gb/s over 4 spans TABLE 3: Comparison between pre and post-compensation scheme for 400-Gb/s over 4 spans For200-Gb/s (320Km) Pre-compensation Post-compensation wavelength Q-Factor BER Q-Factor BER 1574.6 11.84 1E-32 15.08 1.02E-51 1575.42 14.1 1.55E-45 14.32 6.41E-47 1576.25 11.66 8.49E-32 14.5 5.81E-48 1577.08 11.96 2.42E-33 12.05 8.1E-34 1577.9 10.81 1.29E-27 11.81 1.49E-32 1578.73 11.18 2.08E-29 13.51 5.72E-42 1579.56 12.46 5.1E-36 13.46 1.08E-41 1580.38 13.03 3.47E-39 11.67 7.53E-32 1581.21 11.47 7.21E-31 12.29 4.09E-35 1582.04 12.17 1.61E-34 12.34 2.3E-35 1582.87 12.03 1E-33 12.59 9.79E-37 1583.69 11.02 1.24E-28 11.72 4.23E-32 1584.52 13.31 7.93E-41 13.27 1.53E-40 1585.35 11.61 1.43E-31 14.19 4.69E-46 1586.17 10.4 9.53E-26 11.6 1.64E-31 1587 10.91 3.95E-28 11.86 7.45E-33 1587.83 11.05 8.9E-29 11.54 3.32E-31 1588.65 12.11 3.66E-34 13.6 1.54E-42 1589.48 11.2 1.52E-29 12.09 4.88E-34 1590.31 12.67 3.19E-37 14.4 2.04E-47 For400-Gb/s (320Km) Pre-compensation Post-compensation wavelength Q-Factor BER Q-Factor BER 1574.6 7.19 2.56E-13 8.09 2.7E-16 1575.42 8.79 6.15E-19 9.44 1.66E-21 1576.25 8.59 3.75E-18 8.8 5.93E-19 1577.08 8.03 4.06E-16 9.09 4.01E-20 1577.9 7.69 6.1E-15 7.65 8.69E-15 1578.73 8.21 9.56E-17 8.67 1.99E-18 1579.56 8.06 3.04E-16 9.17 2E-20 1580.38 8.56 4.72E-18 8.4 1.97E-17 1581.21 7.6 1.17E-14 9.04 6.5E-20 1582.04 7.41 4.89E-14 7.89 1.39E-15 1582.87 7.49 2.88E-14 8.01 4.95E-16 1583.69 7.12 4.66E-13 7.71 5.55E-15 1584.52 6.9 2.2E-12 7.78 3.27E-15 1585.35 9.35 3.67E-21 9.74 9.15E-23 1586.17 7.68 7.06E-15 7.63 1.04E-14 1587 6.81 3.95E-12 8.26 6.7E-17 1587.83 6.99 1.14E-12 8.3 4.48E-17 1588.65 7.52 2.15E-14 8.32 3.75E-17 1589.48 6.9 2.31E-12 7.38 7.09E-14 1590.31 9.06 5.81E-20 9.08 4.9E-20
  7. 7. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 27 (a) (b) Fig.2: Q versus Wavelength for 200-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation 0 2 4 6 8 10 12 14 16 1570 1575 1580 1585 1590 1595 Q Wavelength Q 0 2 4 6 8 10 12 14 16 1570 1575 1580 1585 1590 1595 Q Wavelength Q
  8. 8. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 28 (a) (b) Fig.3: BER versus Wavelength for 200-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 1570 1575 1580 1585 1590 1595Log(BER) Wavelengtth BER -60 -50 -40 -30 -20 -10 0 1570 1575 1580 1585 1590 1595 Log(BER) Wavelength BER
  9. 9. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 29 (a) (b) Fig.4: Q versus Wavelength for 400-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation 0 1 2 3 4 5 6 7 8 9 10 1570 1575 1580 1585 1590 1595 Q Wavelength Q 0 2 4 6 8 10 12 1570 1575 1580 1585 1590 1595 Q Wavelength Q
  10. 10. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 30 (a) (b) Fig.5: BER versus Wavelength for 400-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation -25 -20 -15 -10 -5 0 1570 1575 1580 1585 1590 1595 Log(BER) Wavelength BER -25 -20 -15 -10 -5 0 1570 1575 1580 1585 1590 1595 Log(BER) Wavelength BER
  11. 11. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 31 We also considered for the distance extension for two data rates 200 and 400-Gb/s. It was found that distance extended to 720 km with acceptable BER for 200-Gb/s but increasing distance for 400-Gb/s Q-value degrades and BER increased to 10^(-7) which shows that increasing data rate, dispersion and non-linearities increases. For 200-Gb/s, simulation was carried out for pre and post- compensation scheme. The post-scheme performed better compare to pre scheme. The Q versus wavelength for all twenty channels wavelength for 200-Gb/s for nine spans (80x9 km) using pre- compensation and post-compensation scheme are plotted in Fig.8 respectively. The measured BER versus wavelength for all twenty channels for 200-Gb/s for nine spans (80x9 km) using pre- compensation and post-compensation method are plotted in Fig.9 respectively. The Eye diagram of first channel (1574.6nm) for pre and post-compensation for 200-Gb/s for nine spans is shown in fig.10. Comparisons between pre and post-scheme in terms of Q factor and BER for 200- Gb/s over nine spans are given in Table 4. The Bold letters in the table indicates the improvement of wavelength in terms of Q-factor and BER for post compensation scheme over pre-compensation scheme. To analyze the system, the results of the first channel have been taken. The Eye diagram of first channel (1574.6nm) for pre and post-compensation for 200-Gbps for four spans is shown in fig.6. The Eye diagram of the pre and post-compensation for 400-Gb/s for four spans is shown in fig.7.The figure clearly shows that eye opening decreases with increase in data rate. (a) (b) Fig.6: Eye Diagram (for first channel) for 200-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation
  12. 12. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 32 TABLE 4: Comparison between pre and post-compensation scheme for 200-Gb/s over 9 spans (a) (b) Fig.7: Eye Diagram (for first channel) for 400-Gb/s over 4 spans (a) for pre-compensation (b) for post-compensation For 200-Gb/s (720Km) Pre-compensation Post-compensation wavelength Q-Factor BER Q-Factor BER 1574.6 6.35 8.48E-11 7.85 1.73E-15 1575.42 8.93 1.62E-19 9.09 4.1E-20 1576.25 8.69 1.51E-18 8.83 4.31E-19 1577.08 6.62 1.43E-11 8.16 1.41E-16 1577.9 6.87 2.43E-12 9.02 7.88E-20 1578.73 5.91 1.23E-09 7.24 1.97E-13 1579.56 7.7 5.17E-15 9.65 1.98E-22 1580.38 8.26 5.76E-17 8.68 1.59E-18 1581.21 6.92 1.68E-12 8.09 2.57E-16 1582.04 6.51 2.74E-11 7.13 4.33E-13 1582.87 7.15 3.48E-13 8.29 4.85E-17 1583.69 7 9.8E-13 7.38 6.44E-14 1584.52 6.85 2.59E-12 9.01 8.81E-20 1585.35 7.09 4.98E-13 8.93 1.66E-19 1586.17 7.05 6.7E-13 8.58 3.95E-18 1587 6.91 1.87E-12 8.07 2.87E-16 1587.83 6.24 1.75E-10 9.07 4.91E-20 1588.65 5.76 3.3E-09 7.96 7.19E-16 1589.48 7.55 1.75E-14 7.37 7.03E-14 1590.31 7.7 5.14E-15 9.71 1.07E-22
  13. 13. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 33 (a) (b) Fig.8: Q versus Wavelength for 200-Gb/s over 9 spans (a) for pre-compensation (b) for post-compensation 0 1 2 3 4 5 6 7 8 9 10 1570 1575 1580 1585 1590 1595 Q Wavelength Q 0 2 4 6 8 10 12 1570 1575 1580 1585 1590 1595 Q Wavelength Q
  14. 14. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 34 -25 -20 -15 -10 -5 0 1570 1575 1580 1585 1590 1595 Log(BER) Wavelength BER (a) (b) Fig.9: BER versus Wavelength for 200-Gb/s over 9 spans (a) for pre-compensation (b) for post-compensation -25 -20 -15 -10 -5 0 1570 1575 1580 1585 1590 1595Log(BER) Wavelength BER
  15. 15. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 35 (a) (b) Fig.10: Eye Diagram (for first channel) for 200-Gb/s over 9 spans (a) for pre-compensation (b) for post-compensation V. CONCLUSION In this paper, we have demonstrated WDM transmission of twenty channels modulated at 10- Gbps and 20-Gbps data rate in the in the lower wavelength region of the L-band using conventional single mode fiber. Each span having a span loss of 27.2 dB was taken considering non-linearities and ASE noise. The total distance covered for 200-Gb/s was nine span (720km) with acceptable BER <10^(-15) and four spans (320km) for 400-Gbps with acceptable BER <10^(-12) by post- compensation scheme, which clearly shows that increasing data rate limits the transmission distance due to increase in non-linearities and dispersion. Also, the simulation was performed for both 200 and 400-Gb/s using pre and post compensation techniques and it was found that post compensation scheme performs better than pre compensation scheme.
  16. 16. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 3, March (2014), pp. 21-36, © IAEME 36 REFERENCES [1] R.S. Kaler, Simulation of 16 × 10 Gb/s, “WDM system based on optical amplifiers at different transmission distance and dispersion,”Int J. of Fiber and Integrated Optics, vol. 21, no.5, Aug 2011. [2] Gurmeet Kaur, M.L.Singh, “Effect of four-wave mixing in WDM optical fiber systems,” Int J. of Fiber and Integrated Optics, vol. 21, no.5, Aug 2007. [3] M.M.Ismaila, M.A.Othmana, Z.Zakariaa, M.H.Misrana, M.A.Meor Saida, H.A.Sulaimana, M.N.Shah Zainudina , M. A. Mutalib, “ EDFA-WDM Optical Network Design System,” Malaysian Technical Universities Conference on Engineering & Technology MUCET in Electronic and Electrical Engineering, 2012. [4] Bo-ning HU, Wang Jing, Wang Wei, Rui-mei Zhao, “Analysis on Dispersion Compensation with DCF based on Optisystem,”2nd International Conference on Industrial and Information Systems, 2010. [5] Bo Dong, Li Wei, and Da-Peng Zhou, “Coupling Between the Small-Core-Diameter Dispersion Compensation Fiber and Single-Mode Fiber and Its Applications in Fiber Lasers,” IEEE J. Lightwave Technology, Vol. 28, no. 9, May 1, 2010. [6] Md. Asiful Islam and M. Shah Alam, Senior Member, IEEE “Design of a Polarization- Maintaining Equiangular Spiral Photonic Crystal Fiber for Residual Dispersion Compensation Over E+S+C+L+U Wavelength Bands,” IEEE Photonics Technology Letters, Vol. 24, no. 11, June 1, 2012. [7] S. Y. Park, G. J. Pendock, A. K. Srivastava, K. Kantor, J. W. Sulhoff, S.J. Sheih, C. Wolf, and Y. Sun, “WDM Transmission in L-Band over Dispersion-Shifted Fiber with 25-dB Span Loss,”IEEE Photonics Technology Letters, Vol. 12, no. 6, June 2000. [8] Divya Dhavan, Neena Gupta, “Optimization of fiber based dispersion compensation in RZ and NRZ data modulation formats,” Journal of Engineering Science and Technology Vol. 6, No. 6, 2011. [9] Mark D. Pelusi, Senior Member, IEEE, “WDM Signal All-Optical Pre-compensation of Kerr Nonlinearity in Dispersion-Managed Fibers,” IEEE Photonics Technology Letters, Vol. 25, no. 1, Jan 1, 2013. [10] G. Agrawal, “Fiber-optic communications systems”, New York, John Wiley & Sons, 2002. [11] G. Keiser, Optical Communications Essentials, The McGraw-Hill, U.S.A, 2004. [12] Manish Saxena, Dr.Anubhuti Khare and Amit R.Mahire, “Comparative Analysis for Higher Channel Isolation using Single FBG Filter and Two FBG Filter Connected One After One for High Dense WDM System”, International Journal of Electronics and Communication Engineering & Technology (IJECET), Volume 4, Issue 2, 2013, pp. 497 - 503, ISSN Print: 0976- 6464, ISSN Online: 0976 –6472. [13] Bhumit P. Patel and Rohit B. Patel, “Comparison of Different Modulation Formats for 8 Channel WDM Optical Network at 40 Gbps Datarate with Non-Linearity”, International Journal of Advanced Research in Engineering & Technology (IJARET), Volume 5, Issue 2, 2014, pp. 37 - 51, ISSN Print: 0976-6480, ISSN Online: 0976-6499.

×