5.1 Kesimpulan
Adapun kesimpulan yang dapat diambil dari Tugas Akhir ini adalah sebagai berikut :
a) Pada sistem CWDM Menggunakan spasi lamda 0,2 nm pada setiap pentransmisiannya, dengan panjang gelombang daerah operasi yang berbeda-beda maka menghasilkan band frekuensi yang berbeda. Semakin besar panjang gelombang daerah operasi maka semakin kecil band frekuensi yang dilewati.
b) Perbedaan spasi kanal berpengaruh pada performansi CWDM.
c) Penggunaan sistem pendingin pada laser dapat mempengaruhi konsumsi daya. Dengan CWDM tidak memerlukan lagi pendingin pada laser sehingga biaya lebih murah.
d) Filter yang digunakan pada CWDM tidak begitu banyak digunakan karena telah menggunakan Thin Film Filter (TFF).
5.2 Saran
Adapun saran adalah sebagai berikut :
Untuk memperoleh gambaran yang lebih jelas tentang kinerja CWDM maka dapat dilakukan dengan sistem simulasi dan perancangan sistem untuk CWDM.
DAFTAR PUSTAKA 1. “Pengenalan Sistem Komunikasi Serat Optik”,
http:/ 2. “Fiber Optik Pada Jaringan Komputer”,
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5. “Eksperimen Gelombang Elektromagnetik”,
http://riyn.multiply.com/journal/item/48/Gelombang_elektromagnetik, tanggal akses 22 juli 2010.
6. Thomas J. Bruno, Paris D. N. Svoronos, 2005 “CRC Handbook of Fundamental Spectroscopic Correlation Charts”, CRC Press. http://id.wikipedia.org/wiki/Spektrum_optik.
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8. Bascom, W. 1964. “Waves and beaches: the dynamics of the ocean surface”, Garden City, NY: Doubleday & Co., Inc. http://bb-jazzy-b.blogspot.com/2009/11/refraksi-cahaya.html.
9. Dolan. Graham, 1996 “Heinemannn Coordinated Science Higher Physics”, Oxford, Heinemann Educational Publishers.
http://125.163.204.22/e_books/modul_online/fisika/MO_90/kb1_2.htm
10.Francesco Maria Grimaldi, Bologna 1665 “Physico mathesis de lumine, coloribus, et iride, aliisque annexis libri duo” Vittorio Bonati.
11.“Dispersi”, http://id.wikipedia.org/wiki/Dispersi, tanggal akses 24 juli 2010. 12.“Frequency Division Multiplexing”,
www.dadan.web.id/frequency-division-multiplexing.html, tanggal akses 24 juli 2010.
13.“Time Division Multiplexing”, http://telekomui.org/?p=97, tanggal akses 24 juli 2010.
14.“MMSI_internet_jaringan-komputer_1-[1]”,
optik, tanggal akses 26 juli 2010.
15.“Teknologi WDM pada Serat Optik”,
tanggal 01 agustus 2010.
16.“optical fiber comunication”,
http:/ 17.Stallings. W, 2007 "Komunikasi Data dan Komputer", Pearson Education, Inc,
http://en.wikipedia.org/wiki/Wavelength-division_multiplexing.
18.“Simplex dan Duplex”, http://id.wikipedia.org/wiki/Simplex, tanggal akses 03 agustus 2010.
19.“THE BASICS OF FIBER OPTIC CABLE (Single-mode multi-mode)”, http://www.arcelect.com/fibercable.htm, tanggal akses 03 agustus 2010.
20.Ma, Andre.Y.16 Mei 2009, “Research Project : AWG Technology in DWDM System”,
http://www.physics.pdx.edu/~larosaa/Applied_optics_464564/Projects_Presen ted/Andre_Ma_Array_Waveguide_Grating_and_DWDM.pdf.
21.Bandung, 18 September 2004 “Dasar Sistem KomunikasiOptik”, PT TELEKOMUNIKASI INDONESIA, Tbk TELKOMRisTI (R & D Center), http://free-pdfebooks.com/?s=dasar+telekomunikasi+modern.
22.Keiser. Gerd, (August 2003), “Optical Communications Essentials” McGraw-Hill Networking Professional,
http://en.wikipedia.org/wiki/Optical_fiber_connector.
23.Andika. Gilang, dkk.17 Mei 2009. “ Teknologi WDM pada Serat Optik “.http://telekomui.org/wp-content/uploads/2006/12/paper-jso-kel6.pdf.
24.Hecht. Jeff, 1987. “ Understanding Fiber Optics “. Fourth Edition. Published by Prentice-Hall, Inc.
25.Keiser. Gerd, Singapore 2000 “ Optical Fiber Communication “, McGraww-Hill International Edition.
26.San Fransisco 2002 “Characteristisc of CWDM : Roots, Current Status, Future Oppoturnities”, Redfern Broadband Network Inc.http://www.rbni.com.
27.Crisp. John dan Barry Elliot, jakarta 2006 “ Serat Optik : Sebuah Pengantar”, edisi ketiga, Erlangga.
28.“CWDM Technologyi, Aplication and Operation”NEC Corporation Of America,
29.“Dense Wavelength Division Multiplexing (DWDM)”, http://kuliit.blogspot.com/2009/01/dwdm-dense-wavelength-divison.html, tanggal akses 03 agustus 2010.
30.Sudarmilah. Endah, Surakarta Maret 2002 “Dense Wavelength Division Multiplexing (DWDM) sebagai Solusi Krisis Kapasitas Banwidth pada Transmisi Data”, Jurnal Teknik Elektro Universitas Muhammadiah.
31.Nubeling. Markus, 03 Juli 2002 “CWDM: lower cost for more capacity in the short-haul”, Fiber Network Engineering.
32.“CWDM Module 4-channel/8-channel”,
agustus 2010.
33.Kusuma .Dr. Tb. Maulana, ”Optical Fiber Communication”,
tanggal akses 26 juli 2010.
Table 8-6/G.959.1 – Single-channel IrDI parameters and values for optical tributary signal class NRZ 10G short-haul applications for G.652 fibre
Parameter Units P1S1-2D1 P1S1-2D2a P1S1-2D2b 1S1-2D2bF G.691 Application code S-64.1 S-64.2a S-64.2b
General information – Maximum number of
channels
– 1 1 1 1
Bit rate/line coding of optical tributary signals
– NRZ 10G NRZ 10G NRZ 10G NRZ OTU2 FEC enabled Maximum bit error ratio – 10–12 10–12 10–12 10–12 (Note 2)
Fibre type – G.652 G.652 G.652 G.652
Interface at point MPI-S Operating wavelength range
nm 1290-1330 1530-1565 1530-1565 1530-1565
Source type – SLM SLM SLM
Maximum spectral power density
mW/ 10 MHz
ffs ffs ffs Ffs
Minimum side mode suppression ratio
dB 30 30 30 30
Maximum mean output power
dBm +5 −1 +2 +2
Minimum mean output power
dBm +1 −5 −1 −2
Minimum extinction ratio dB 6 8.2 8.2 8.2
Eye Mask – NRZ 10G 1310 nm region NRZ 10G 1550 nm region NRZ 10G 1550 nm region NRZ 10G 1550 nm region Optical path from point
MPI-S to MPI-R Maximum attenuation dB 11 11 11 12 Minimum attenuation dB 6 7 3 3 Maximum chromatic dispersion ps/nm 70 800 800 800
Minimum optical return loss at MPI-S
dB 14 24 24 24
Maximum discrete reflectance between MPI-S and MPI-R
dB –27 −27 −27 −27
Maximum differential group delay
ps 30 30 30 30
Interface at point MPI-R Maximum mean input power
dBm –1 −8 −1 -1
Minimum sensitivity dBm –11 −18 −14 -16
LAMPIRAN
penalty
Maximum reflectance of optical network element
dB –14 −27 −27 -27
NOTE 1 – Application codes with a suffix "a" have transmitter power levels appropriate to APD receivers; application codes with the suffix "b" have transmitter power levels appropriate to PIN receivers.
NOTE 2 – The BER for this application code is required to be met only after the error correction (if used) has been applied. The BER at the input of the FEC decoder can therefore be significantly higher than 10-12.
Table 8-7/G.959.1 – Single-channel IrDI parameters and values for optical tributary signal class NRZ 10G short-haul applications for G.653 and
G.655 fibre
Parameter Units P1S1-2D3a
P1S1-2D5a P1S1-2D3b P1S1-2D5b 1S1-2D3bF 1S1-2D5bF G.691 Application code S-64.3a S-64.5a S-64.3b S-64.5b General information – Maximum number of channels – 1 1 1
Bit rate/line coding of optical tributary signals
– NRZ 10G NRZ 10G NRZ OTU2 FEC enabled Maximum bit error
ratio – 10–12 10–12 10–12 (Note 2) Fibre type – G.653, G.655 G.653, G.655 G.653, G.655 Interface at point MPI-S Operating wavelength range nm 1530-1565 1530-1565 1530-1565 Source type – SLM. SLM SLM Maximum spectral power density mW/ 10 MHz ffs ffs Ffs
Minimum side mode suppression ratio dB 30 30 30 Maximum mean output power dBm −1 +2 +2 Minimum mean output power dBm −5 −1 −2 Minimum extinction ratio dB 8.2 8.2 8.2
Table 8-7/G.959.1 – Single-channel IrDI parameters and values for optical tributary signal class NRZ 10G short-haul applications for G.653 and
G.655 fibre
Parameter Units P1S1-2D3a
P1S1-2D5a P1S1-2D3b P1S1-2D5b 1S1-2D3bF 1S1-2D5bF Eye Mask – NRZ 10G 1550 nm region NRZ 10G 1550 nm region NRZ 10G 1550 nm region Optical path from
point MPI-S to MPI-R Maximum attenuation dB 11 11 12 Minimum attenuation dB 7 3 3 Maximum chromatic dispersion ps/nm 130 130 130 Minimum optical return loss at MPI-S
dB 24 24 24
Maximum discrete reflectance between MPI-S and MPI-R
dB −27 −27 −27 Maximum differential group delay ps 30 30 30 Interface at point MPI-R
Maximum mean input power
dBm −8 −1 −1
Minimum sensitivity dBm −17 −13 −15
Maximum optical path penalty dB 1 1 1 Maximum reflectance of optical network element dB −27 −27 −27
NOTE 1 – Application codes with a suffix "a" have transmitter power levels appropriate to APD receivers; application codes with the suffix "b" have transmitter power levels
appropriate to PIN receivers.
NOTE 2 – The BER for these application codes is required to be met only after the error correction (if used) has been applied. The BER at the input of the FEC decoder can therefore be significantly higher than 10-12.
Singlemode Fiber Types
There are several designations used to describe various types of SM fiber that are often confusing. Here are the ones in common use today.
Description IEC SMF
Type ITU Spec. TIA Spec
Standard Singlemode
Fiber B1.1 G.652 OS1
Cutoff Shifted Fiber B1.2 G.654
Low Water Peak Fiber B1.3 G.652 OS2
Dispersion Shifted Fiber B2 G.653 Non-Zero Dispersion
Shifted Fiber B4 G.655
The standards bodies with vested interest in the governance of optical fiber specifications are:
ISO (International Organization for Standardization) – Formed of manufacturers and standards bodies representing over 90 nations. For optical fiber specifications and standards, ISO and IEC collaborate on several Joint Technical Committees (JTC).
IEC (International Electrotechnical Commission) – IEC addresses the electronics and telecommunications industries, and counts over 50 nations among its membership. The current IEEE 802.3 standard for Ethernet cites TIA-568 and ISO/IEC 11801 for optical fiber specifications.
TIA (Telecommunications Industry Association) – Now part of the Electronic Industries Alliance (EIA). TIA is comprised of manufacturers who are primarily suppliers to the telecom industry but include other interested groups. TIA is primarily involved (through the American National Standards Institute or ANSI) in optical fiber and system test standards.
ITU (International Telecommunication Union) – The ITU is part of the United Nations System of Organizations, and over 180 countries currently are represented within the ITU. The ITU administers the commonly referenced single-mode fiber standards documents, G.652 through G.655, as required by telecom systems manufcturers and their customers.
The ITU has defined a series of recommendations that describe the geometrical properties and transmissive properties of multimode and single-mode fiber-optic cables. The four most important recommendations are listed here:
ITU G.652 Covers single-mode NDSF (non-dispersion-shifted fiber). This fiber is in most of the cable that was installed in the 1980s. Optimized in the 1,310-nm range. Low water peak fiber has been specifically processed to reduce the water peak at 1400 nm to allow use in that range. There are 4 subcategories:
G.652A : Atten </= 0.5 / 0.4 at 1310 / 1550nm Macrobend </= 0.5 dB at 1550nm PMD </= 0.5 ps/sqrt(km) G.652B : Atten </= 0.4 / 0.35 / 0.4 at 1310 / 1550 / 1625nm Macrobend </= 0.5 dB at 1625nm PMD </= 0.2 ps/sqrt(km) G.652C :
Atten </= 0.4 from 1310 to 1625nm, </= 0.3 at 1550nm, and
at 1383nm, it must be </= that specified at 1310nm, after hydrogen aging. Macrobend </= 0.5 dB at 1625nm
PMD </= 0.5 ps/sqrt(km) G.652D (covers all above):
Atten </= 0.4 from 1310 to 1625nm, </= 0.3 at 1550nm, and
at 1383nm, it must be </= that specified at 1310nm, after hydrogen aging. Macrobend </= 0.5 dB at 1625nm
PMD </= 0.2 ps/sqrt(km)
ITU G.653 Covers single-mode dispersion-shifted optical fiber. Dispersion is minimized in the 1,550-nm wavelength range. At this range attenuation is also minimized, so longer distance cables are possible.
ITU G.654: Covers single-mode fibre which has the zero-dispersion wavelength around 1300 m wavelength which is cut-off shifted and loss minimized at a wavelength around 1550 nm and which is optimized for use in the 1500-1600 nm region.
ITU G.655 Covers single-mode NZ-DSF (nonzero dispersion-shifted) fiber) , which takes advantage of dispersion characteristics that suppress the growth of four-wave mixing, a problem with WDM (wavelength division multiplexing) systems. NZ-DSF supports high-power signals and longer distances, as well as closely sp G.655 is optimized for WDM and long-distance cable runs such as transoceanic cables. It uses dispersion to reduce the effect of four-wave mixing (FWM), which occurs in DWDM systems when three wavelengths mix in such a way to produce a fourth wavelength that overlays and interferes with the original signals.
TIA TR-42 specifies singlemode fiber for premises applications. OS1 or OS2 fiber for outdoor or indoor/outdoor applications is specified for a maximum
attenuation of 0.5 dB/km at either 1310 05 1550 nm. For indoor applications, OS1 or OS2 fiber is specified for a maximum attenuation of 1.0 dB/km at either 1310 05 1550 nm.
Fiber Types
This section discusses various MMF and SMF types currently used for premise, metro, aerial, submarine, and long-haul applications. The International Telecommunication Union (ITU-T), which is a global standardization body for telecommunication systems and vendors, has standardized various fiber types. These include the 50/125-u graded index fiber (G.651), Nondispersion-shifted fiber (G.652), dispersion-shifted fiber (G.653), 1550-nm loss-minimized fiber (G.654), and NZDSF (G.655).
Multimode Fiber with a 50-Micron Core (ITU-T G.651)
The ITU-T G.651 is an MMF with a 50 micron nominal core diameter and a 125-u nominal cladding diameter with a graded refractive index. The atten125-uation parameter for G.651 fiber is typically 0.8 dB/km at 1310 nm. The main application for ITU-T G.651 fiber is for short-reach optical transmission systems. This fiber is optimized for use in the 1300-nm band. It can also operate in the 850-nm band.
Nondispersion-Shifted Fiber (ITU-T G.652)
Production volumes starting in 1984Improved 1550 nM attenuation (0.25 db/km) in 1989 Even better (0.20 db/km) in 1992 Controlled low PMD since 1996. The ITU-T G.652 fiber is also known as standard SMF and is the most commonly deployed fiber. This fiber has a simple step-index structure and is optimized for operation in the 1310-nm band. It has a zero-dispersion wavelength at 1310 nm and can also operate in the 1550-nm band, but it is not optimized for this region. The typical chromatic dispersion at 1550 nm is high at 17 ps/nm-km. Dispersion compensation must be employed for high-bit-rate applications. The attenuation parameter for G.652 fiber is typically 0.2 dB/km at 1550 nm, and the PMD parameter is less than 0.1 ps/km. An example of this type of fiber is Corning SMF-28.
Low Water Peak Nondispersion-Shifted Fiber (ITU-T G.652.C)
The legacy ITU-T G.652 standard SMFs are not optimized for WDM applications due to the high attenuation around the water peak region. ITU G.652.C-compliant fibers offer extremely low attenuation around the OH peaks. The G.652.C fiber is optimized for networks where transmission occurs across a broad range of wavelengths from 1285 nm to 1625 nm. Although G.652.C-compliant fibers offer excellent capabilities for shorter, unamplified metro and access networks, they do not fully address the needs for 1550-nm transmission. The attenuation parameter for G.652 fiber is typically 0.2 dB/km at 1550 nm, and the PMD parameter is less than 0.1 ps/ km. An example of this type of fiber is Corning SMF-28e.
Low Water Peak Nondispersion-Shifted Fiber (ITU-T G.652.D)
There are four tables in the standard. A and B have a water peak. C and D eliminate the water peak for full spectrum operation. D has controlled PMD. Dispersion-Shifter Fiber (ITU-T G.653)
Conventional SMF has a zero-dispersion wavelength that falls near the 1310-nm window band. SMF shows high dispersion values over the range between 1500 nm and 1600 nm (third window band). The trend of shifting the operating transmission wavelength from 1310 nm to 1550 nm initiated the development of a fiber type called dispersion-shifted fiber (DSF). DSF exhibits a zero-dispersion value around the 1550-nm wavelength where the attenuation is minimum. The DSFs are optimized for operating in the region between 1500 to 1600 nm. With the introduction of WDM systems, however, channels allocated near 1550 nm in DSF are seriously affected by noise induced as a result of nonlinear effects caused by FWM. This initiated the development of NZDSF. Figure 3-14 illustrates the dispersion slope of DSF with respect to SMF and NZDSF. G.653 fiber is rarely deployed any more and has been superseded by G.655.
Figure 1. Fiber Dispersion Slopes 1550-nm Loss-Minimized Fiber (ITU-T G.654)
The ITU-T G.654 fiber is optimized for operation in the 1500-nm to 1600-nm region. This fiber has a low loss in the 1550-nm band. Low loss is achieved by using a pure silica core. ITU-T G.654 fibers can handle higher power levels and have a larger core area. These fibers have a high chromatic dispersion at 1550 nm. The ITU G.654 fiber has been designed for extended long-haul undersea applications.
Nonzero Dispersion Shifted Fiber (ITU-T G.655)
Using nonzero dispersion-shifted fiber (NZDSF) can mitigate nonlinear characteristics. NZDSF fiber overcomes these effects by moving the zero-dispersion wavelength outside the 1550-nm operating window. The practical effect of this is to have a small but finite amount of chromatic dispersion at 1550
nm, which minimizes nonlinear effects, such as FWM, SPM, and XPM, which are seen in the dense wavelength-division multiplexed (DWDM) systems without the need for costly dispersion compensation. There are two fiber families called nonzero dispersion (NZD+ and NZD), in which the zero-dispersion value falls before and after the 1550-nm wavelength, respectively. The typical chromatic dispersion for G.655 fiber at 1550 nm is 4.5 ps/nm-km. The attenuation parameter for G.655 fiber is typically 0.2 dB/km at 1550 nm, and the PMD parameter is less than 0.1 ps/ km. The Corning LEAF fiber is an example of an enhanced G.655 fiber with a 32 percent largereffective area. Figure 3-14 illustrates the dispersion slope of NZDSF with respect to SMF and DSF.
From the ITU - One more type
ITU has set a global standard for a new optical fibre that will make it easier for network operators to deploy bandwidth to maximise technology in core networks. The development of standards in this area is important if network operators are to reduce costs and provide more innovative services to customers.
"G.656 is another significant step in the evolution of optical networks, because it allows a more economical deployment of optical transport networks", says Peter Wery, Chairman of ITU-T Study Group 15 responsible for the Recommendation. The new standard Recommendation G.656 will allow the easier deployment of Coarse Wave Division Multiplexing (CWDM) in metropolitan areas, and increase the capacity of fibre in Dense Wave Division Multiplexing (DWDM) systems. Wave Division Multiplexing (WDM)increases the data carrying capacity of an optical fibre by allowing simultaneous operation at more than one wavelength. G.656 allows operators using CWDM to deploy systems without the need to compensate for chromatic dispersion, a phenomenon that at low levels counteracts distortion, but at high-levels can make a signal unusable. Although complicated, the management of chromatic dispersion is crucial as the number of wavelengths used in WDM systems increase. ITU has a history of providing the specifications that allow operators to most efficiently handle this.
G.656 also means that at least 40 more channels can be added to DWDM systems. In this case chromatic dispersion is used to control harmful interference over this unprecedented range of the optical spectrum.
Note to technical editors:
The most important new feature in Recommendation G.656 fibre is the chromatic dispersion coefficient. In G.656 this coefficient has an allowed range of 2 to 14 ps/nm*km in the 1460-1625 nm band, compared to 1 to 10 ps/nm*km for G.655.B and G.655.C which is only related to the 1530-1565 nm band. This low value of the chromatic dispersion coefficient in the S-C-L bands is the real novelty of G.656 because it allows the utilization of a larger wavelength band.
The other characteristics are very similar to previous Recommen- dations. The range of mode field diameter permitted in G.656 of 7 to 11 5m compares to 8 to
11 5m in the G.655 non-zero dispersion-shifted fibre. G.656 fibre has a maximum PMD link design value of 0.20 ps/sqrtkm, which is the lowest value recom-mended by ITU-T (the same value that ITU-T recently adopted for G.655.C). G.656 has the same cable cut-off wavelength and cable
attenuation coefficients in the C and L bands as G.655.
ITU-T G.656 (Characteristics of a fibre and cable with Non-Zero Dispersion for Wideband Optical Transport) is the most recent in the G-series which specifies the geometrical, physical, mechanical and transmission characteristics of the optical fibres. Other Recommendations in this series include:
Yet another ITU addition G.657
Cooked up for the cable TV and FTTH industries. It is hard to control bend radius in the field. This fiber is designed for installation abuse.
G.657 Cat A -- Max 0.75 dB for a full turn around a 2 cm mandrel G.657 Cat B -- Max 0.5 dB for a full turn around a 1.5 cm mandrel Both at 1550 nm
ITU-T G.652 - Characteristics of a single-mode optical fibre and cable
ITU-T G.653 - Characteristics of a dispersion-shifted single-mode optical fibre and cable
ITU-T G.654 - Characteristics of a cut-off shifted single-mode optical fibre cable ITU-T G.655 - Characteristics of a non-zero dispersion-shifted single-mode optical fibre and cable
The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this
Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation.
− ITU-T Recommendation G.652 (20053), Characteristics of a single-mode optical fibre cable.
− ITU-T Recommendation G.653 (2003), Characteristics of a dispersion-shifted single-mode optical fibre cable.