1 Pertemuan 03 Transmisi Data Matakuliah: H0174/Jaringan Komputer Tahun: 2006 Versi: 1/0

2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Menjelaskan transmisi data

3 Outline Materi Mode transmisi Metode transmisi Media Transmisi

4 KOMPONEN Transmitter Receiver Medium –Guided medium twisted pair, optical fiber –Unguided medium air, water

5 TEKNIK TRANSMISI DATA MODE TRANSMISI DATA: –PARALEL –SERIAL ASINKRON SINKRON METODE TRANSMISI – SIMPLEX – HALF DUPLEX – FULL DUPLEX BENTUK FISIK –BOUNDED/GUIDED MEDIUM (KABEL, SERAT OPTIK) – UNBOUNDED/UNGUIDED MEDIUM (MICROWAVE)

6 KARAKTERISTIK –MEMBERIKAN LEBAR RENTANG FREKUENSI (BANDWIDTH) YANG DAPAT DILAYANI GANGGUAN –RANDOM: THERMAL NOISE, IMPULSE, CROSS TALK, ETC –SYSTEMATIC: – ATTENUATION, DELAY, ETC. TEKNIK TRANSMISI DATA LST/FASKD/CINQ

7 Paralel Transmission

8 Serial transmission

9 ASINKRON TRANSMISI ASINKRON: –PENGIRIMAN INFORMASI BIASANYA DILAKUKAN PER UNIT DATA ( 5 - 8) BIT –SINKRONISASI DAN RESINKRONISASI DENGAN START/STOP BIT –TIMING HANYA PERLU DIJAGA PADA TIAP UNIT DATA –START/STOP MERUPAKAN OVERHEAD YANG TINGGI –DIGUNAKAN TERUTAMA UNTUK TERMINAL DAN DATA BERUPA KARAKTER LST/FASKD/CINQ

10 Synchronous Transmission

11 TRANSMISI SINKRON –PENGIRIMAN INFORMASI DILAKUKAN PER BLOK DATA DENGAN PERINTAH PENGENDALIAN TERMASUK DALAM BLOK INFORMASI –OVERHEAD SANGAT RENDAH –MEMBUTUHKAN SINKRONISASI YANG RUMIT: SINKRONISASI BIT SINKRONISASI KARAKTER/OKTET SINKRONISASI FRAME

12 Metode Transmisi Simplex –One direction e.g. Television Half duplex –Either direction, but only one way at a time e.g. police radio Full duplex –Both directions at the same time e.g. telephone

13 MEDIA TRANSMISI UNBOUNDED/UNGUIDED: –GELOMBANG ELEKTROMAGNETIK GELOMBANG VHF GELOMBANG UHF GELOMBANG MIKRO SPREAD SPEKTRUM SATELIT BOUNDED/GUIDED: –KABEL TEMBAGA TWISTED PAIR –UNSHIELDED –SHIELDED –KABEL KOAKSIAL –SERAT OPTIK MONO MODE MULTI MODE

14 Guided Transmission Media Twisted Pair Coaxial cable Optical fiber

15 Pertemuan 04 Transmisi Data - Lanjutan Matakuliah: H0174/Jaringan Komputer Tahun: 2006 Versi: 1/0

16 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Menjelaskan transmisi data

17 Outline Materi Media Gangguan

18 Coaxial Cable

19 Coaxial Cable Applications Television distribution –Antenna to TV –Cable TV + Cable Modem

20 Optical Fiber

21 Optical Fiber Transmission Modes

22 Optical Fiber - Characteristic Greater capacity (Data rates of hundreds of Gbps) Smaller size & weight Lower attenuation Electromagnetic isolation Greater repeater spacing

23 Spektrum untuk Communication

24 Transmission Frequencies 2GHz to 40GHz –Microwave –Highly directional –Point to point –Satellite 30MHz to 1GHz –Omnidirectional –Broadcast radio 3 x to 2 x –Infrared –Local

25 BandRangePropagationApplication VLF3–30 KHzGroundLong-range radio navigation LF30–300 KHzGround Radio beacons and navigational locators MF300 KHz–3 MHzSkyAM radio HF3–30 MHzSky Citizens band (CB), ship/aircraft communication VHF30–300 MHz Sky and line-of-sight VHF TV, FM radio UHF300 MHz–3 GHzLine-of-sight UHF TV, cellular phones, paging, satellite SHF3–30 GHzLine-of-sightSatellite communication EHF30–300 GHzLine-of-sightLong-range radio navigation Bands

26 Wireless Propagation Signal travels along three routes –Ground wave Follows contour of earth (up to 2MHz, AM radio) –Sky wave Amateur radio, BBC world service, Voice of America Signal reflected from ionosphere layer of upper atmosphere (actually refracted) –Line of sight Above 30Mhz

27 Satellite Point to Point Link

28 Satellite Broadcast Link

29 Transmission Impairments Signal received may differ from signal transmitted Analog - degradation of signal quality Digital - bit errors Caused by –Attenuation and attenuation distortion –Delay distortion –Noise

30 Attenuation Signal strength falls off with distance Depends on medium Received signal strength: –must be enough to be detected –must be sufficiently higher than noise to be received without error Attenuation is an increasing function of frequency

31 Noise Additional signals inserted between transmitter and receiver Thermal –Due to thermal agitation of electrons –Uniformly distributed –White noise Intermodulation –Signals that are the sum and difference of original frequencies sharing a medium

32 Noise Crosstalk –A signal from one line is picked up by another Impulse –Irregular pulses or spikes External electromagnetic interference Short duration High amplitude