Exploring Transmission Media in Telecommunication Networks

1. ET2080 JARINGAN TELEKOMUNIKASI Transmission Media TutunJuhana – Program StudiTeknik Telekomunikasi STEI - ITB

2. Tipe-tipe Media Transmisi • Guided transmission media • Kabel tembaga • Open Wires • Coaxial • Twisted Pair • Kabel serat optik • Unguided transmission media • infra merah • gelombang radio • microwave: terrestrial maupun satellite ET2080 Jaringan Telekomunikasi

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4. Guided Transmission Media Waves are guided along solid medium ET2080 Jaringan Telekomunikasi

5. Model Saluran Transmisi • Menurut Telegrapher's Equations, suatu saluran transmisi terdiri dari serangkaian komponen kutub dua yang jumlahnya tak terhingga • R menyatakan resistensi konduktor • L menyatakan induktansi salurann • C menyatakan kapasitansi antara dua konduktor • G menyatakan konduktansi materi dielektrik yang memisahkan kedua konduktor • Impedansi karakteristik dinyatakan oleh ET2080 Jaringan Telekomunikasi

6. Kabel Tembaga • Paling lama dansudahbiasadigunakan • Kelemahan: redamantinggidansensitifterhadapinterferensi • Redamanpadasuatukabeltembagaakanmeningkatbilafrekuensidinaikkan • Kecepatanrambatsinyaldidalamkabeltembagamendekati 200.000 km/detik • Tigajeniskabeltembaga yang biasadigunakan: • Open wire • Coaxial • Twisted Pair ET2080 Jaringan Telekomunikasi

7. Open wire • Sudah jarang digunakan • Kelemahan: • Terpengaruh kondisi cuaca dan lingkungan • Kapasitas terbatas (hanya sekitar 12 kanal voice) 70 miles open wire from Hawthorne to Tonopah Photograph taken by Brian Hayes in 1999 (http://flickr.com/photos/brianhayes/321552411/) ET2080 Jaringan Telekomunikasi

8. Coaxial • Bandwidth lebar (45-500 MHz) • Lebih kebal terhadap interferensi • Contoh penggunaan : pada antena TV, • LAN dsb. = CORE (D) = DIELECTRIC(C) = SHIELD (B) = JACKET(A) RG58 coax and BNC Connector ET2080 Jaringan Telekomunikasi

9. Source: Radio Laboratory Handbook, School On Digital Radio Communications for Research and Training in Developing Countries, ICTP ET2080 Jaringan Telekomunikasi

10. Twisted pair • Twisted pair dibangundariduakonduktor yang dipilin • Kabeldipilinuntukmengeliminasi crosstalk • Pada suatu bundel twisted pair (lebih dari satu pasang), twist length (twist rates) masing-masing pasangan dibedakan untuk mencegah crosstalk antar pasangan • Pengirimansinyalpada twisted pair menggunakan“balance signaling”untuk mengeliminasi pengaruhinterferensi (noise) ET2080 Jaringan Telekomunikasi

11. Balance Signaling • A balanced transmission line is one whose currents are symmetric with respect to ground so that all current flows through the transmission line and the load • none through ground • Note that line balance depends on the current through the line, not the voltage across the line • It is also called differential signaling Source: York County Amateur Radio Society ET2080 Jaringan Telekomunikasi

12. Examples of a Balanced LineAll using DC rather than AC to simplify the analysis • Notice that the currents are equal and opposite and that the total current flowing through ground = 25mA-25mA = 0 Example #1 ET2080 Jaringan Telekomunikasi

13. Note that the total current flowing through ground is again 0 • Because the ground current is 0, the ground is not required Example #2 ET2080 Jaringan Telekomunikasi

14. Is the line balanced? • No – although the voltages are equal and opposite, the currents are not! Example #3 ET2080 Jaringan Telekomunikasi

15. FYI: • Coaxial is an example of unbalanced transmission line • Many types of antenna (dipoles, yagi etc.) are balanced load • So, to feed balanced antenna with unbalance transmission lines we have to use baluns (balance-unbalance) ET2080 Jaringan Telekomunikasi

16. Twisted pairs Types • Unshielded Twisted pair (UTP) • Shielded Twisted pair (STP) ET2080 Jaringan Telekomunikasi

17. Unshielded Twisted pair (UTP) • Category 1- originally designed for voice telephony only, but thanks to some new techniques, long-range Ethernet and DSL, operating at 10Mbps and even faster, can be deployed over Cat 1 • Category 2 - accommodate up to 4Mbps and is associated with token-ring LANs. • Category 3 - Cat 3 cable operates over a bandwidth of 16MHz on UTP and supports up to 10Mbps over a range of 330 feet (100 m). • Key LAN applications include 10Mbps Ethernet and 4Mbps token-ring LANs. ET2080 Jaringan Telekomunikasi

18. UTP (cont.) • Category 4 • operates over a bandwidth of 20MHz on UTP • can carry up to 16Mbps over a range of 330 feet (100 m). • The key LAN application is 16Mbps token ring. • Category 5 • operates over a bandwidth of 100MHz on UTP • Can handle up to 100Mbps over a range of 330 feet (100m). • Cat 5 cable is typically used for Ethernet networks running at 10Mbps or 100Mbps. • Key LAN applications include 100BASE-TX, ATM, CDDI, and 1000BASE-T. • It is no longer supported, having been replaced by Cat 5e. ET2080 Jaringan Telekomunikasi

19. Category 5e • Cat 5e (enhanced) operates over a bandwidth of 100MHz on UTP, with a range of 330 feet (100 m). • The key LAN application is 1000BASE-T. • The Cat 5e standard is largely the same as Category 5, except that it is made to somewhat more stringent standards. • Category 5e is recommended for all new installations and was designed for transmission speeds of up to 1Gbps (Gigabit Ethernet). • Although Cat 5e can support Gigabit Ethernet, it is not currently certified to do so. ET2080 Jaringan Telekomunikasi

20. UTP (cont.) • Category 6 - specified under ANSI/TIA/EIA-568-B.2-1, • Operates over a bandwidth of up to 400MHz • Supports up to 1Gbps over a range of 330 feet (100 m). • Cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Cat 5/5e and Cat 3 cable standards. • Cat 6 features more stringent specifications for crosstalk and system noise. • Cat 6 is suitable for 10BASE-T/100BASE-TX and 1000BASE-T (Gigabit Ethernet) connections. ET2080 Jaringan Telekomunikasi

21. Shielded Twisted Pair (STP) • Twisted pair cables are often shielded in attempt to prevent electromagnetic interference. • Because the shielding is made of metal, it may also serve as a ground. • However, usually a shielded or a screened twisted pair cable has a special grounding wire added called a drain wire. • This shielding can be applied to individual pairs, or to the collection of pairs. • When shielding is applied to the collection of pairs, this is referred to as screening. • The shielding must be grounded for the shielding to work. ET2080 Jaringan Telekomunikasi

22. STP (cont.) • Screened unshielded twisted pair (S/UTP) • Also known as Fully shielded (or Foiled) Twisted Pair (FTP), is a screened UTP cable (ScTP). • Shielded twisted pair (STP or STP-A) • Screened shielded twisted pair (S/STP or S/FTP) ET2080 Jaringan Telekomunikasi

23. Screened unshielded twisted pair (S/UTP) ET2080 Jaringan Telekomunikasi ET2080 Jaringan Telekomunikasi

24. Shielded twisted pair (STP or STP-A) 1 – Jacket2 – Shield-foil3 – Drain wire4 – Solid twisted pair ET2080 Jaringan Telekomunikasi

25. Screened shielded twisted pair (S/STP or S/FTP) 1 – Jacket 2 – Rip-cord 3 – Shield-foil 4 – Drain wire 5 – Protective skin 6 – Polymer tape 7 – Solid twisted pair ET2080 Jaringan Telekomunikasi

26. Category 7 • Cat 7 is specified in the frequency range of 1MHz to 600MHz. • ISO/IEC11801:2002 Category 7/Class F is a cable standard for Ultra Fast Ethernet and other interconnect technologies that can be made backward compatible with traditional Cat 5 and Cat 6 Ethernet cable. • Cat 7, which is based on four twisted copper pairs, features even more stringent specifications for crosstalk and system noise than Cat 6. • To achieve this, shielding has been added for individual wire pairs and the cable as a whole ET2080 Jaringan Telekomunikasi

27. Cable Legend ET2080 Jaringan Telekomunikasi

28. Optical Fiber ET2080 Jaringan Telekomunikasi

29. Optical Fiber Advantages • Weight and Size • Fiber cable is significantly smaller and lighter than electrical cables to do the same job • Material Cost • Fiber cable costs significantly less than copper cable for the same transmission capacity • Information Capacity • Recently, bit-rates of up to 14 Tbit/s have been reached over a single 160 km line using optical amplifiers • No Electrical Connection • Electrical connections have problems: • Ground loops (in a conductor connecting two points that are supposed to be at the same potential, often ground, but are actually at different potentials) causing noises and interferences • Dangerous (must be protected) • Lightning poses a severe hazard • No Electromagnetic Interference • Because the connection is not electrical, you can neither pick up nor create electrical interference (the major source of noise) • Longer distances between Regenerators (hundreds of kilometers) • Open Ended Capacity • The maximum theoretical capacity of installed fiber is very great (almost infinite) • Better Security • It is possible to tap fiber optical cable. But it is very difficult to do and the additional loss caused by the tap is relatively easy to detect ET2080 Jaringan Telekomunikasi

30. Optical Fiber Elements • Core • Carries the light signal (pure silica glass and doped with germanium) • Cladding • Keeps light signal within core (Pure Silica Glass) • Coating • Protects Optical Fiber From Abrasion and External Pressures (UV Cured Acrylate) ET2080 Jaringan Telekomunikasi

31. Mengapa cahaya bisa bergerak sepanjang serat optik? • Karena ada fenomenaTotal Internal Reflection (TIR) • TIR dimungkinkan dengan membedakan indeks bias (n) antara core dan clading • Dalam hal ini ncore > ncladding • Memanfaatkan hukum Snellius ET2080 Jaringan Telekomunikasi

32. Remembering Snellius ncore > ncladding ET2080 Jaringan Telekomunikasi

33. Critical angle • At the critical angle we know that q² equals 90° and sin 90° = 1 and so ET2080 Jaringan Telekomunikasi

34. for rays where q1is less than a critical value then the ray will propagate along the fiber and will be “bound” within the fiber (Total Internal Reflection) • where the angle q1 is greater than the critical value the ray is refracted into the cladding and will ultimately be lost outside the fiber ET2080 Jaringan Telekomunikasi

35. Numerical Aperture (NA) ET2080 Jaringan Telekomunikasi

36. Light Modes • Can be as few as one mode and as many as tens of thousands of modes ET2080 Jaringan Telekomunikasi

37. Fiber Transmission Windows (Bands) ET2080 Jaringan Telekomunikasi

38. Transmitter Light Sources • Light Emitting Diodes (LED) • Used for multimode: 850 nm or 1300 nm • Wide beam width fills multimode fibers • Wider spectrum (typically 50 nm) • Inexpensive • Cannot modulate as fast as lasers • VCSEL’s–Vertical Cavity Surface Emitting Laser • Used for multimode at 850 and 1300 nm • Quite narrow spectrum • Narrow beam width (does not fill multimode fibers) • Much less expensive than FP or DFB lasers • Fabry-Perot (FP) and Distributed Feedback (DFB) Lasers • Used for singlemode: 1310 nm or 1550 nm • Narrow spectrum (can be less than 1 nm) • Narrow beam width (does not fill multimode fibers) • Highest power and fastest switching–Most expensive (especially DFB) ET2080 Jaringan Telekomunikasi

39. Salah satu cara untuk mengidenifikasi konstruksi kabel optik adalah dengan menggunakan perbandingan antara diameter core dan cladding. Sebagai contoh adalah tipe kabel 62.5/125. Artinya diamater core 62,5 micron dan diameter cladding 125 micron • Contoh lain tipe kabel:50/125, 62.5/125 dan 8.3/125 • Jumlah core di dalam satu kabel bisa antara 4 s.d. 144 ET2080 Jaringan Telekomunikasi

40. Klasifikasi Serat Optik • Berdasarkan mode gelombang cahaya yang berpropagasi pada serat optik • Multimode Fibre • Singlemode Fibre • Berdasarkan perubahan indeks bias bahan • Step index fibre • Gradded index fibre ET2080 Jaringan Telekomunikasi

41. Step Index Fiber vs Gradded Index Fiber • Pada step index fiber, perbedaan antara index bias inti dengan index bias cladding terjadisecaradrastis ET2080 Jaringan Telekomunikasi

42. Pada gradded index fiber, perbedaan index bias bahan dari inti sampai cladding berlangsung secara gradual • Contoh profile gradded index: • Untuk 0 ≤r ≤ a • r= jari-jari di dalam inti serat • a = jari-jari maksimum inti serat ET2080 Jaringan Telekomunikasi

43. Multimode Optical Fiber Step-index multimode. Used with 850nm, 1300 nm source. Graded-index multimode. Used with 850nm, 1300 nm source. ET2080 Jaringan Telekomunikasi

44. Singlemode Optical Fiber ET2080 Jaringan Telekomunikasi

45. Distortions in Fiber • If a short pulse of light from a source such as a laser or an LED is sent down a narrow fiber, it will be changed (degraded) by its passage down the fiber • It will emerge (depending on the distance) much weaker • lengthened in time (“smeared out”), and • distorted in other ways • The reasons for the above are as follows: • Attenuation • Maximum Power • Polarization • Dispersion • Noise ET2080 Jaringan Telekomunikasi

46. Attenuation External Internal Single-modefibers will not tolerate a minimum Bend Radius  of less than 6.5 to 7.5 cm Graded-Index Multimode Fiber will typically tolerate a minimum bend radius of not less than 3.8 cm The fibers commonly used in customer-premises applications (62.5-m core) can tolerate a bend radius of less than an inch (2.5 cm). (Source: timbercon.com) ET2080 Jaringan Telekomunikasi

47. Dispersion • Dispersion occurs when a pulse of light is spread out during transmission on the fiber ET2080 Jaringan Telekomunikasi

48. Material Dispersion (chromatic dispersion) • Lasers and LEDs produce a range of optical wavelengths (a band of light) rather than a single narrow wavelength • The fiber has different refractive index characteristics at different wavelengths and therefore each wavelength will travel at a different speed in the fiber • Thus, some wavelengths arrive before others and a signal pulse disperses (or smears out) • Expressed in picoseconds per kilometer per nanoseconds (ps/km/n) • Maximum information-carrying capacity at 1310 nm also known at zero-dispersion wavelength ET2080 Jaringan Telekomunikasi

49. Modal dispersion • When using multimode fiber, the light is able to take many different paths or “modes” as it travels within the fiber • The distance traveled by light in each mode is different from the distance travelled in other modes • Therefore, some components of the pulse will arrive before others • Not issue in single mode fiber ET2080 Jaringan Telekomunikasi

50. Bandwidth-distance product 50 • Because the effect of dispersion increases with the length of the fiber, a fiber Information carrying capacity is often characterized by its bandwidth-distance product, often expressed in units of MHz×km. • This value is a product of bandwidth and distance because there is a trade off between the bandwidth of the signal and the distance it can be carried • For example, a common multimode fiber with bandwidth-distance product of 500 MHz×km could carry a 500 MHz signal for 1 km or a 1000 MHz signal for 0.5 km. ET2080 Jaringan Telekomunikasi ET2080 Jaringan Telekomunikasi