TeknikTelekomunikasi Seluler, Sukiswo ST, MT 1 KOMUNIKASI WIRELESS. Sukiswo

Transkripsi

1 1 KOMUNIKASI WIRELESS Sukiswo

2 Pendahuluan Tujuan : menjelaskan dasar-dasar komunikasi wireless 2

3 Outline Komunikasi Wireless / Nirkabel Pemanfaatan Komunikasi Nirkabel Macam2 Komunikasi Nirkabel Standard Komunikasi Nirkabel Evolusi Komunikasi Nirkabel Kontent & Aplikasi Spektrum Frekuensi Frekuensi Carrier / Kanal Mode Komunikasi 3

4 Komunikasi Nirkabel Sistem Komunikasi menggunakan frekuensi/spektrum radio, yang memungkinkan transmisi (pengiriman/penerimaan) informasi (suara, data, gambar, video) tanpa koneksi fisik Dibedakan dari sistem transmisi yang memerlukan koneksi fisik, seperti kabel/kawat tembaga atau fiber optik Bersifat tetap (fixed) atau bergerak (mobile) Dibatasi oleh ketersediaan spektrum (pita frekuensi), karena adanya interferensi (saling mengganggu) jika digunakan bersama 4

5 Komunikasi Nirkabel 5

6 Komunikasi Nirkabel Komunikasi menggunakan gelombang elektromagnetik Gelombang elektromagnetik Kecepatan cahaya (c = 3x10 8 m/s) Memiliki frekuensi (f) dan panjang gelombang (l)» c = f x l Penggunaan frekuensi lebih tinggi umumnya medium meredam lebih besar 6

7 Komunikasi Nirkabel Dapat dilakukan dimana saja (mobile) Bisa bersifat lebih personal Dibatasi oleh sifat antarmuka terminal: Layar kecil (ponsel) sampai menengah (laptop) Tombol terbatas Daya terbatas 7

8 Klasifikasi Komunikasi Nirkabel Wireless Communication Fixed Wireless Mobile Wireless Non Cellular Cellular Non Cellular Cellular contoh : point to point communication, infra red communication, LMDS, Microwave communication contoh : PHS, CT2, PACS, DCS1800, DECT contoh : paging system (ERMES, NTT, NEC), dispatching system, PAMR (Public Access Mobile Radio) dsb contoh : GSM, CDMA/IS-95, AMPS, UMTS, PHS, DCS1800, NMT450, TACS, C-450, CDMA 2000 dsb 8

9 Pemanfaatan Teknologi Nirkabel Layanan Bersifat tetap (fixed): Penggunaan sekitar rumah (Cordless-DECT) Sambungan lokal (wireless local loop-wll) Bluetooth: jarak pendek, kecepatan rendah WiFi: jarang menengah, kecepatan cukup tinggi WIMAX: jarak jauh, kecepatan tinggi Satellite: jangkauan luas, kecepatan menengah RFID: jangkauan sangat kecil Layanan Bersifat bergerak (mobile): Limited Mobility (Flexi) Cellular (GSM, CDMA, 3G) Satellite (GMPCS) 9

10 Macam2 Teknologi Nirkabel Degree of mobility Standing Walking Driving GSM GPRS DECT CDMA EDGE BlueTooth UMTS EV-DO EV-DV HSDPA FlashOFDM (802.20) Systems beyond 3G >2010 UMTS WLAN (IEEE x) IEEE e IEEE a,d Mbps User data rate 10

11 IEEE , IEEE Standard Nirkabel IEEE (Zigbee Alliance) Sensors (BAN) RFID (AutoID Center) IEEE IEEE IEEE e IEEE d WiMAX IEEE Wi-Fi Alliance RAN WAN MAN LAN 3GPP (GPRS/UMTS) 3GPP2 (1X--/CDMA2000) GSMA, OMA ETSI HiperMAN & HIPERACCESS ETSI-BRAN HiperLAN2 BAN: Body Area Network IEEE UWB, Bluetooth Wi-Media, BTSIG, MBOA PAN ETSI HiperPAN 11

12 System Evolution Scenario Generation 1 st Generation (Cellular) Analog voice nd Generation Digital voice & Low rate data 3 rd Generation Voice & High speed data Multimedia 4 th Generation WLAN++ ALL-IP Broadband Ubiquitous & Seamless TRmax ( Mbps ) Maximum transmission rate WLAN n, etc. WiMAX WLAN a,HiSWANa, UWB, etc. HIPERLAN2, etc. 3G+ Nomadic HSDPA, cdma2000(3x), etc. 3G Bluetooth, etc. W-CDMA, Local Cdma2000, etc. 4G G+ Mobile PDC,GSM,PHS, etc. 2G PDC,GSM,PHS, etc. ~ Year 12

13 GSM Evolution GSM CS Up to 9,6 Kbps GSM GPRS Up to 115 kbps UMTS Up to 2 Mbps or 384 in mobility 2G GSM HSCSD Up to 38,4 kbps 2.5G 3G EDGE Operators prefer choose direct going to GPRS technology rather than going to GSM HSCSD technology because no HSCSD handset availability and short time stage 13

14 CDMA Standards Evolution IS-95A CDMA Voice, packet- 9.6/14.4 Kbps IS-95B CDMA Voice, packet- 64 Kbps IS X 144 Kbps 600 Kbps peak IS XEV-DO 600 Kbps; 2.4 Kbps peak IS XEV-DV 2-5 Mbps peak All IP Source: CDMA2000-A world view 14

15 IMT-2000 (Family of Standards) IMT-2000 Terrestrial Radio Interfaces IMT-2000 CDMA Direct Spread IMT-2000 CDMA Multi Carrier IMT-2000 CDMA TDD IMT-2000 TDMA Single Carrier IMT-2000 FDMA/ TDMA WCDMA (UMTS) CDMA2000 1X and 3X UTRA TDD And TD-SCDMA UWC-136/ EDGE DECT CDMA TDMA FDMA 15

16 Content & Aplikasi 16

17 Spektrum frekuensi Radio Spectrum Micro wave IR UV X-Rays Cosmic Rays MHz ==100m 100MHz ==1m 10GHz ==1cm Alokasi Frekeunsi! Visible light < 30 KHz VLF KHz LF 300KHz 3MHz MF 3 MHz 30MHz HF 30MHz 300MHz VHF 300 MHz 3GHz UHF 3-30GHz SHF > 30 GHz EHF 17

18 Contoh : panjang gelombang GSM : Frekuensi ~= 900 Mhz Panjang gelombang ~= 33cm PCS Frekuensi ~= 1.8 Ghz Panjang gelombang ~= 17.5 cm Bluetooth: Frekuensi ~= 2.4Gz Panjang gelombang ~= 12.5cm 18

19 Frequency Carrier/Kanal Informasi yang dikirim menuju receiver dilewatkan pada band frekuensi tertentu. Disebut sebagai kanal (channel) Tiap kanal memiliki bandwidth yang tetap (dalam KHz) dan kapasitas (bit-rate) Band frekuensi yang berbeda (atau kanal) dapat digunakan untuk mentransmisikan informasi secara paralel dan independen (konsep multiple access). 19

20 Example Station A Assume a spectrum of 90KHz is allocated over a base frequency b for communication between stations A and B Assume each channel occupies 30KHz. There are 3 channels Each channel is simplex (Transmission occurs in one way) For full duplex communication:» Use two Channel different 1 (b -channels b+30) (front and reverse channels) Channel 2 (b+30 - b+60)» Use time division in a channel Channel 3 (b+60 - b+90) Station B 20

21 Simplex Communication Normally, on a channel, a station can transmit only in one way. This is called simplex transmision To enable two-way communication (called full-duplex communication) We can use Frequency Division Multiplexing We can use Time Division Multiplexing 21

22 Duplex Communication - FDD FDD: Frequency Division Duplex Mobile Terminal M Forward Channel Reverse Channel Base Station B Forward Channel and Reverse Channel use different frequency bands 22

23 Duplex Communication - TDD TDD: Time Division Duplex Mobile Terminal M M B M B M B Base Station B A singe frequency channel is used. The channel is divided into time slots. Mobile station and base station transmits on the time slots alternately. 23

24 Example - Frequency Spectrum Allocation in U.S. Cellular Radio Service Reverse Channel Forward Channel MHz MHz Channel Number Reverse Channel 1 <=N <= <= N <= 1023 Center Frequency (MHz) 0.030N (N-1023) Forward Channel 1 <=N <= <= N <= 1023 (Channels are unused) Channel bandwidth is 45 MHz 0.030N (N-1023)

25 What is Mobility Initially Internet and Telephone Networks is designed assuming the user terminals are static No change of location during a call/connection A user terminals accesses the network always from a fixed location Mobility and portability Portability means changing point of attachment to the network offline Mobility means changing point of attachment to the network online 25

26 Degrees of Mobility Walking Users Vehicles Low speed Small roaming area Usually uses high-bandwith/low-latency access High speeds Large roaming area Usually uses low-bandwidth/high-latency access Uses sophisticated terminal equipment (cell phones) 26

27 The Need for Wireless/Mobile Networking Demand for Ubiquitous Computing Anywhere, anytime computing and communication You don t have to go to the lab to check your Pushing the computers more into background Focus on the task and life, not on the computer Use computers seamlessly to help you and to make your life more easier. Computers should be location aware Adapt to the current location, discover services 27