Digital Data and Line Coding Data and Computer

Digital Data and Line Coding Data and Computer Communication Suherman, Ph. D Reference: Wikipedia elearning. vtu. ac. in

Digital Data • Dipresentasikan dengan nilai “ 0” dan “ 1” • Pasangan “ 0” dan “ 1” disebut binary number (biner) • Banyaknya nilai “ 0” dan “ 1” tiap detik disebut dengan “bit rate”. • Dalam line/baseband coding dan broadband coding (modulasi), terkadang 1 digit diwakili 1 simbol, tapi juga terkadang 2, 4, 8 bit diwakili 1 simbol. Banyaknya simbol per detik disebut “Baud rate”.

Sumber Data Digital • Digitalisasi suara: suara analog, disampling kemudian diubah menjadi data digital: PCM 24, PCM 30, ADPCM, CELP dan vocoder lainnya. • Transducer: alat ukur yang mengubah karakteristik alam menjadi data biner. • Video. • Data.

Line Coding • Line coding atau baseband coding adalah pengkodean nilai “ 0” dan “ 1” dalam tegangan listrik. • Dibutuhkan agar simbol “ 0” dan “ 1” dapat ditransmisikan secara efective melalui kabel. • Representasi “ 0” dan “ 1” bervariasi. Karena perubahan pulsa tegangan memiliki spektrum frekuensi, maka dibutuhkan representasi yang efektif, agar kecepatan transfer semakin tinggi.

Line Coding • Dimana saja line coding dibutuhkan? • Serial: Non-Return-to-Zero (NRZ), Polar NRZ, NRZ inverted, Bipolar encoding, Manchester encoding, Differential Manchester encoding, HDB 3. • Serial interfacing: RS-series (RS-232), TIA-series, EIA-series, MIL-series. • Paralel interfacing: LPT-series, IEEE-1284, dll • Connector: DE-9 (DB-9), DB 25, RJ 11, RJ 45, DIN-8, dll

Line Coding Unipolar Coding:

Line Coding • Polar Coding

Line Coding • Non-Return to Zero (NRZ)

Line Coding • Return to Zero (RZ)

Line Coding • Manchester Coding

Line Coding • Differential Manchester Coding

Line Coding • AMI (Alternate Mark Inversion) atau Bn. ZS (Bipolar n-Zero Substitution)

Line Coding • 2 B 1 Q (2 -Binary 1 -Quartenary) - Four voltage level

Line Coding • MLT 3 (Multi Line Transmission Three Leve)

Studi Lanjut Common line codes • • • • • • AMI Modified AMI codes: B 8 ZS, B 6 ZS, B 3 ZS, HDB 3 2 B 1 Q 4 B 5 B 4 B 3 T 6 b/8 b encoding Hamming Code 8 b/10 b encoding 64 b/66 b encoding 128 b/130 b encoding Coded mark inversion (CMI) Conditioned Diphase Eight-to-Fourteen Modulation (EFM) used in Compact Disc EFMPlus used in DVD RZ — Return-to-zero NRZ — Non-return-to-zero NRZI — Non-return-to-zero, inverted Manchester code (also variants Differential Manchester & Biphase mark code) pulse-position modulation (a generalization of Manchester code) Miller encoding (also known as Delay encoding or Modified Frequency Modulation, and has variant Modified Miller encoding) MLT-3 Encoding Hybrid Ternary Codes Surround by complement (SBC) TC-PAM Serial – Paralel Port Connectors Optical line codes: • • Carrier-Suppressed Return-to-Zero Alternate-Phase Return-to-Zero

Thesis? ? - Analysis dan Simulasi Representasi Spektral Line Coding