STRUKTUR JARINGAN PLMN

STRUKTUR JARINGAN PLMN
Program S1 Teknik Telekomunikasi Jurusan Teknik Elektro STT Telkom Jaringan Telekomunikasi

Jaringan Telekomunikasi
History Generasi pertama (1G) Sistem komunikasi seluler pertama kali beroperasi di Norwegia pada tahun 1981 dan diikuti oleh sistem yang sama di US dan UK. System generasi pertama ini hanya mentransmisikan voice dengan frekuensi sekitar 900 MHz dan menggunakan modulasi analog Generasi kedua (2G) GSM (Global System for Mobile Communications) pertama kali digunakan di eropa pada awal tahun GSM menyediakan layanan voice dan data yang terbatas. Menggunakan modulasi digital. The new third generation (3G) cellular services Universal Mobile Telecommunications System (UMTS) or IMT-2000 will sustain higher data rates still and opens the door to many internet style applications Jaringan Telekomunikasi

History 1934-USA : AM based: First generation Analogue Cellular Systems For public safety 5000 mobiles Vehicle ignition noise a major problem 1935 USA Europe Asia :FM based: Frequency bands: MHz and MHz 120 kHz RF bandwidth with channel spacing of 30 kHz Data rate kbps No of channels 400 – 1000, half-duplex 1946- USA : First Generation Public Mobile Telephone Service: Coverage distance: 50 km, 60 kHz bandwidth Single powerful transmitter Jaringan Telekomunikasi

History - 1st Generation (1G) Systems
1960 Cellular Radio, developed by Bell Labs. 1970 Cellular Mobile System (USA) 1980 First Generation Analogue Cellular Systems Advanced Mobile Telephone Systems (AMPS) Frequency bands: MHz and MHz Channel spacing 30 kHz and no of channels Data rate kbps FM for speech, FSK for signaling, FDM Jaringan Telekomunikasi

History - 2nd Generation (2G) Systems (1991-2)
Group Special Mobile (GSM) – Europe (GSM 1.8 GHz, and 1.9 GHz) U.S. Digital Cellular (USDC) and CDMA (USDC 1.9 GHz) Digital Cordless Systems (DCS) 1.8 GHz Technology: TDMA, TDMA hybrid FDMA Characteristics: Digital voice and low speed data Frequency 900 MHz, RF channel spacing 200 kHz Modulation: GMSK, DPSK, Fixed frequency assignment Speech rate 13 kbps, Speech coding, TDMA High security and higher capacity, Improved speech Quality of service (QoS) Jaringan Telekomunikasi

History - 3rd Generation (3G) Systems (1995 - )
Support Multimedia Services: Especially Internet Service, 144kb/s (Outdoor and higher velocity ), 384kb/s(from outdoor to indoor), 2Mb/s (indoor); Speech of QoS and other services First Transitional System: 2 GHz nd Transitional Systems: 2.5 GHz st CDMA 144 k bps 2002- Handover between GSM and WCDMA Jaringan Telekomunikasi

Early Mobile Systems Layanan mobile tradisional dibangun mirip dengan televisi broadcasting Satu pemancar dengan daya yang besar ditempatkan pada titik yang paling tinggi yang dapat meliputi area dengan radius sampai dengan 50 km Sistem seluler dibentuk dari jaringan telepon mobile dengan cara: menggunakan daya pancar yang rendah untuk mencakup area yang lebih luas  contoh area metropolitan dibagi ke dalam 100 sel yang berbeda dimana masing-masing sel dgn 12 kanal Jaringan Telekomunikasi

Early Mobile Systems Early Mobile Radio Systems Satu pemancar dengan daya pancar yang besar Area cakupan yang bagus, tetapi tidak memungkinkan dilakukan penggunaan ulang ( reuse) frekuensi yang sama (e.g., Bell Mobile System ‘70 -- max 12 calls over thousand sq. Miles) Jaringan Telekomunikasi

Cellular Systems Cellular Concept technique of using a fixed a number of channels to serve an arbitrary large number of subscribers by reusing channels throughout the coverage area high system capacity in a limited spectrum many low powered transmitters (small cells) each base station allocated a portion of the spectrum neighboring base stations assigned different groups of channels Jaringan Telekomunikasi

Cellular Systems Solves the problem of Spectral congestion and user capacity by means of frequency reuse Offers high capacity in a limited spectrum allocation Offers system level approach, using low power transmitters instead of a single, high power transmitter (large cell) to cover larger area. A portion of the total channels available is allocated to each base station. Neighbouring base stations are assigned different groups channels, in order to minimise interference. Jaringan Telekomunikasi

Model pola radiasi R R R R R Model radiasi mana yang paling bagus ? Jaringan Telekomunikasi

With the shift parameters i and j defined in the figure, we see that the number of cells in a cluster is given by and the frequency reuse distance is given by Jaringan Telekomunikasi

PLMN ? Jaringan seluler atau PLMN (public land mobile network) terdiri dari sejumlah mobile station (MS) yang dihubungkan dengan jaringan radio ke infrastruktur perangkat switching yang berinterkoneksi dengan sistem lain seperti PSTN Jaringan Telekomunikasi

Perbandingan PSTN dan PLMN
Jaringan Telekomunikasi

Elemen PLMN Elemen PLMN terdiri dari Elemen jaringan untuk user (trafik) Elemen jaringan sebagai database Elemen jaringan untuk tambahan jaringan pintar (IN) Elemen jaringan untuk operasi dan pemeliharahan (O&M) Elemen jaringan untuk signaling Elemen jaringan untuk transport dan transmisi Note : pada bab ini diberikan contoh untuk jaringan GSM Jaringan Telekomunikasi

Elemen Jaringan GSM Network elements for (user) traffic MS BTS BSC MSC Gateway MSC (GMSC) Short message service centre (SMS-C) Network elements as databases HLR VLR AUC EIR Network elements for additional network intelligence service control points (SCPs) and service switching points (SSPs) Network elements for operation and maintenance operations support system (OSS) and a network management system (NMS). Jaringan Telekomunikasi

Elemen Jaringan GSM Network elements for signalling Since a GSM network utilises signaling system No. 7 (SS7), either integrated or stand-alone signal transfer points (STPs) are required. Network elements for transport and transmission transmission over radio access, plesiochronous digital hierarchy (PDH), synchronous digital hierarchy (SDH) or synchronous optical network (SONET) systems are used. Jaringan Telekomunikasi

OPERATION OF THE CELLULAR PHONE When the mobile unit is active (i.e. when a mobile phone is switched on), it register with the appropriate BS , depending on its location, and its cell position is stored at the responsible MSC. When a call is set-up (when a user makes a call), the base station monitors the quality of the signal for the duration of the call, and reports that to the controlling MSC, which in turn makes decisions concerning the routing of the call. When a cellular phone moves from one cell to the other, the BS will detect this from the signal power and inform the MSC of that. The MSC will then switch the control of the call to the BS of the new cell, where the phone is located. This is called handover . It normally takes up to 400 ms, which is not noticeable for voice transmission. A cellular phone user can only use his/her mobile within the covered area of the network. Roaming is the capacity of a cellular phone, registered on one system, to be able to enter and use other systems. Those other systems must be compatible to enable roaming (i.e. they must have the same type of networks). Jaringan Telekomunikasi

What happens when a cellular user turns on their phone?
Terminal scans control channels and locks on to strongest one. If can’t find a strong enough signal, “no service” With receiver turned to strongest control channel, terminal extracts important information from broadcast channel. Strongest Signal Jaringan Telekomunikasi

What happens when a cellular user turns on their phone? (cont) On interpreting this broadcast information, terminal turns on “roaming” sign, determines DCC, paging channels, etc. Once this initialization is complete, mobile enters idle mode. When no call in progress, terminal monitors paging messages in order to detect arrival of a new call. Paging Channel (one of broadcast channels) Page for User with MIN X User with Mobile Identification Number (MIN) X Jaringan Telekomunikasi

What happens when a cellular user turns on their phone? (cont) Power consumed by radio receiver while it waits for paging message has strong influence on standby time of terminal’s battery. Terminals can operate in sleep mode when no call in progress. In this mode, terminal turns off its receiver for significant fraction of time. Wakes up for short period of time. If there is paging message for terminal, BS schedules message to arrive during brief wake-up interval. This is synchronized by using a hyperframe counter. Paging messages arrive in SPACH blocks of superframe. Indicates assigned traffic channels, etc. Jaringan Telekomunikasi

Masalah dalam jaringan seluler
Number of Channels Per Cell Fading Co-Channel Interference Handovers Multiple access Jaringan Telekomunikasi

Masalah dalam jaringan seluler Number of Channels Per Cell When the number of channels per cell is small (less transmitting channels) base station congestion is very likely to occur. Increasing the number of channels to solve this problem could be a problem since the bandwidth allocated for uplink and downlink transmission is fixed. Therefore increasing the channel number per cell would cause the channel frequencies used in a cell to be re-used in a closer cell. This increases co-channel interference. Solution Use a microcellular network since it can increase the number of channels per cell without an increase in co-channel interference Jaringan Telekomunikasi

Masalah dalam jaringan seluler FADING This is the reduction of signal power. Fading is caused by many factors - the most important ones being multipath and shielding. Multipath fading is caused by the transmission of the signal along different paths and resulting in simultaneous reception. Depending of the amplitudes and phase of the signal, the result of this could be that the signals cancel each other completely or significant attenuation in the resultant signal. Shielding is the absence of field strength. Most common causes are tunnels, hills and inside certain buildings Solution The receiver at the BS should have an equaliser circuit to compensate for fading. Equaliser finds how a known transmitted signal (transmitted with the desired signal) was modified by multipath fading and shielding. Using this information, an inverse filter is constructed and the desired signal is extracted Jaringan Telekomunikasi

Masalah dalam jaringan seluler Co-Channel Interference Co-channels are the same channels (or frequencies) that are used by different cells. To avoid this kind of interference, it is necessary to separate the co-channels by as great distance as possible. But, by doing so, channel capacity will be compromised. Solution Here, microcells could be used to decrease co-channel interference for a particular capacity wanted. Alternatively, the Equaliser can also be used to minimise the effect of co-channel interference on the desired signal. Jaringan Telekomunikasi

Masalah dalam jaringan seluler Handovers Handover does not pose serious problems in Digital Data Cellular Networks. WHY? In circuit-switch networks, handover is a major problem, because the radio link between the MS and the BS which is continuously available is lost. During the time in which the link is lost, both the MS and the BS could be transmitting data which will be lost unless effective buffering is provided. In Digital Data Cellular Network considered, there is no continuous link between the MS and the BS. Packets are transmitted and received by the MS only after the BS informs it to do so. So, the link between the MS and the BS only lasts for one time slot (time in which a packet can be transmitted and received). Therefore, handover can only cause, if any, a few packet loss and does not pose a serious problem. Jaringan Telekomunikasi

Masalah dalam jaringan seluler Jaringan Telekomunikasi

Teknologi Seluler 1G wireless - Analog voice service - No data service AMPS (Advanced Mobile Phone Service) - Digital voice service - 9.6K to 14.4K bit/sec. - CDMA, TDMA and PDC offer one-way data transmissions only - Enhanced calling features like caller ID - No always-on data connection CDMA (Code Division Multiple Access) TDMA (Time Division Multiple Access) GSM (Global System for Mobile Communications) PDC (Personal Digital Cellular) 2G wireless - Superior voice quality - Up to 2M bit/sec. - always-on data - Broadband data services like video & multimedia - Enhanced roaming W-CDMA (Wide-band Code Division Multiple Access) CDMA-2000 3G wireless Jaringan Telekomunikasi

Block diagram of the first generation cellular network.
All first generation cellular networks are based on analog technology and use FM modulation. An example of the first generation cellular telephone system is Advanced Mobile Phone Services (AMPS) AMPS Pioneer of cellular telecommunications FDMA-based analog system Low capacity of subscriber per cell Unsecure Phone number can be scanned and copied Voice conversation is not encrypted Jaringan Telekomunikasi

Second Generation Wireless Networks
Second generation wireless systems employ digital modulation and advanced call processing capabilities. Examples of second generation wireless systems include : Global System for Mobile (GSM), IS-54 TDMA and IS-95 CDMA TIA digital standards. Jaringan Telekomunikasi

GSM Jaringan Telekomunikasi

Global System for Mobile Communications Beroperasi pada band frekuensi 900, 1800 atau 1900 MHz . Teknologi seluler paling populer hampir di seluruh negara-negara di dunia TDMA-based digital system 8 kali kapasitas AMPS per frequency band Secure Seluruh informasi yang dipertukarkan antara Mobile Station (MS) dan Base Station (BS) dienkripsi Jaringan Telekomunikasi

Architecture of the GSM network

Elemen jaringan GSM untuk user (trafik)
Network elements for (user) traffic MS BSS terdiri dari dua buah perangkat : BTS dan BSC MSC gateway MSC (GMSC) Short message service centre (SMS-C) IMS Jaringan Telekomunikasi

MOBILE STATION The mobile station consists of the mobile equipment, i.e. the handset, and a smart card called the Subscriber Identity Module (SIM). The SIM provides personal mobility, so that the user can have access to subscribed services irrespective of a specific terminal. By inserting the SIM card into another GSM terminal, the user is able to receive and make calls from that terminal, and receive other subscribed services. The mobile equipment is uniquely identified by the International Mobile Equipment Identity (IMEI). The SIM card contains the International Mobile Subscriber Identity (IMSI) used to identify the subscriber to the system, a secret key for authentication and other information. The IMEI and the IMSI are independent, thereby allowing personal mobility. The SIM card may be protected against unauthorized use by a password or personal identity number. Jaringan Telekomunikasi

Mobile station ME + MS = SIM Merupakan terminal transceiver Diidentifikasikan dengan IMEI tertentu IMEI = International Mobile Equipment Identity MS terdiri dari : Mobile Equipment (ME)/HP Subscriber Identification Module (SIM) Jaringan Telekomunikasi

SIM Card Subscriber Identity Module (SIM) adalah sebuah smart card yang berisi seluruh informasi user dan beberapa feature dari GSM Informasi yang ada berupa : Authentication Key “Ki” 2 algorithma enkripsi. Yaitu algoritma autentikasi A3 dan A8 sebagai cipher key IMSI and TMSI Service tambahan SIM card dilindungi oleh sebuah mekanisme Personal Identity Number (PIN) yang dimiliki user Jaringan Telekomunikasi

Base Transceiver Station (BTS) BSS terdiri dari dua buah perangkat : Base Transceiver Station (BTS) Base Station Controller (BSC) BTS merupakan tranceiver yang mendefinisikan sebuah sel dan menangani hubungan link radio dengan MS. BTS terdiri dari perangkat pemancar dan penerima, seperti antena dan pemroses sinyal untuk sebuah interface Jaringan Telekomunikasi

BTS Jaringan Telekomunikasi

Base Station Controller BSC mengatur sumber radio untuk sebuah BTS atau lebih. BSC merutekan panggilan ke MSC BSC menangani radio-channel setup, frequency hopping, dan handover intern BSC Menangani proses call control Maintain database pelanggan Maintains record panggilan untuk billing Jaringan Telekomunikasi

BSC Jaringan Telekomunikasi

Network Sub-system (NSS) NSS terdiri dari : Mobile Switching Center (MSC) Home Location Register (HLR) Visitor Location Register (VLR) Authentication Center (AuC) Equipment Identity Register (EIR) Jaringan Telekomunikasi

Network Sub-system (NSS)

Mobile Switching Center (MSC) Melakukan fungsi switching dasar Mengatur BSC melalui A-interface Sebagai penghubung antara satu jaringan GSM dengan jaringan lainnya melalui Internetworking Function (IWF) MSC Provides and controls mobile access to the PSTN. Interprets the dialed number, routes and switches call to destination number. Also manages mobile’s supplementary services. Maintains a register of visitors operating within the coverage area of the MSC’s connected BTSs. PDSN: Packet data service node is basically a packet router. Mobile Switching Centre (MSC) : This controls a number of cells (or cluster), arranges base stations and channels for the mobiles and handles connections. Jaringan Telekomunikasi

Network elements as databases
HLR Home Location Register VLR Visitor Location Register AUC Authentication Center EIR Equipment Identity Register Jaringan Telekomunikasi

Home Location Register (HLR) HLR berisi rekaman database permanen dari pelanggan dan merupakan database user yang utama. HLR juga berisi rekaman lengkap lokasi terkini dari user. Jaringan Telekomunikasi

Visitor Location Register (VLR) VLR berisi database sementara dari pelanggan VLR digunakan untuk pelanggan lokal dan yang sedang melakukan roaming. VLR memiliki pertukaran data yang luas daripada HLR. VLR diakses oleh MSC untuk setiap panggilan, dan MSC dihubungkan dengan VLR Setiap MSC terhubung dengan sebuah VLR, tetapi satu VLR dapat terhubung dengan beberapa MSC Jaringan Telekomunikasi

Authentication Center (AuC) Berisi parameter authentikasi pelanggan untuk mengakses jaringan GSM. AuC berisi parameter seperti Ki, algorithma A3 atau A8 AuC memproduksi tiga buah parameter autentikasi seperti (SRES, RAND, Kc) dan menyimpannya di VLR. Jaringan Telekomunikasi

Equipment Identity Register (EIR) EIR merupakan register penyimpan data seluruh mobile stations EIR berisi IMEI (international Mobile Equipment Identities), yang merupakan nomor seri perangkat + tipe code tertentu Mobile Equipment dibagi menjadi tiga kelompok : Black list Grey list White list * catatan: EIR belum diterapkan di Indonesia. Jaringan Telekomunikasi

Operation Sub-system (OSS) Operation dan Maintenance Jaringan Pengaturan pelanggan dan tagihan Pengaturan Mobile Equipment Jaringan Telekomunikasi

Interface Antara BTS dan BSC dihubungkan oleh Abis interface BTS berkomunikasi dengan MS dengan Um interface MSC Transcoder BSC BTS A Interface Ater Interface Abis Interface Jaringan Telekomunikasi

Konsep kanal pada GSM Kanal terdiri dari dua jenis : Kanal fisik: Satu TimeSlot(TS) frameTDMA merupakan satu kanal fisik Setiap carrier RF terdiri dari 8 TS(CH 0 – 7) Kanal Logic: Kanal Trafik (TCH) dapat membawa suara atau data untuk layanan komunikasi. TCH dibagi dua jenis, full rate channel dengan Bit rate 13 Kbps dan half rate channel dengan kecepatan bit 6,5 Kbps Kanal Kontrol digunakan untuk keperluan signalling Kanal logik ditumpangkan pada kanal fisik Jaringan Telekomunikasi

Konsep Kanal GSM Jaringan Telekomunikasi

Traffic channels Jaringan Telekomunikasi

Control channels Common channels can be accessed both by idle mode and dedicated mode mobiles. The common channels are used by idle mode mobiles to exchange the signaling information required to change to dedicated mode. Mobiles already in dedicated mode monitor the surrounding base stations for handover and other information. The common channels are defined within a 51-frame multiframe, so that dedicated mobiles using the 26-frame multiframe TCH structure can still monitor control channels. The common channels include: Broadcast Control Channel (BCCH) Continually broadcasts, on the downlink, information including base station identity, frequency allocations, and frequency-hopping sequences Jaringan Telekomunikasi

Control Channel Frequency Correction Channel (FCCH) and Synchronization Channel (SCH) Used to synchronize the mobile to the time slot structure of a cell by defining the boundaries of burst periods, and the time slot numbering. Every cell in a GSM network broadcasts exactly one FCCH and one SCH, which are by definition on time slot number 0 (within a TDMA frame) Random Access Channel (RACH) Slotted Aloha channel used by the mobile to request access to the network. Paging Channel (PCH) Used to alert the mobile station of an incoming call. Access Grant Channel (AGCH) Used to allocate an SDCCH to a mobile for signaling (in order to obtain a dedicated channel), following a request on the RACH Jaringan Telekomunikasi

Timing Advance Control Jaringan Telekomunikasi

Hirarki Kanal Logic GSM Jaringan Telekomunikasi

Signal Processing in GSM Jaringan Telekomunikasi

Data Service in GSM Jaringan Telekomunikasi

SPEECH CODING GSM is a digital system, so speech, which is inherently analog, has to be digitized. The GSM group studied several speech coding algorithms on the basis of subjective speech quality and complexity (which is related to cost, processing delay and power consumption once implemented) before arriving at the choice of a Regular Pulse Excited - Linear Predictive Coder (RPE-LPC) with a long term predictor loop. Basically, information from previous samples, which does not change very quickly, is used to predict the current sample. The coefficients of the linear combination of the previous samples, plus an encoded form of the residual, the difference between the predicted and actual sample, represent the signal. Speech is divided into 20 (ms) samples, each of which is encoded as 260 bits, giving a total bit rate of 13kbps (kilobits per second). This is the so-called full-rate speech coding. Recently, an enhanced full-rate (EFR) speech coding algorithm has been implemented by some North American GSM1900 operators. This is said to provide improved speech quality using the existing 13 kbps bit rate. Jaringan Telekomunikasi

FUTURE OF GSM GSM, together with other technologies, is part of an evolution of wireless mobile telecommunication that includes High-Speed Circuit-Switched Data (HSCSD), General Packet Radio System (GPRS), Enhanced Datarate GSM Environment (EDGE), and Universal Mobile Telecommunications Service (UMTS). Jaringan Telekomunikasi

GPRS, EDGE Jaringan Telekomunikasi

Sistem GPRS Secara umum General Packet Radio Service atau GPRS adalah suatu teknologi yang memungkinkan pengiriman dan penerimaan data lebih cepat jika dibandingkan dengan penggunaan teknologi Circuit Switch Data atau CSD. Jaringan GPRS merupakan jaringan terpisah dari jaringan GSM dan saat ini hanya digunakan untuk aplikasi data. Komponen-komponen utama jaringan GPRS adalah : GGSN; gerbang penghubung jaringan GSM ke jaringan internet SGSN; gerbang penghubung jaringan BSS/BTS ke jaringan GPRS PCU; komponen di level BSS yang menghubungkan terminal ke jaringan GPRS Secara teori kecepatan pengiriman data GPRS dapat mencapai 115 kb/s. Namun dalam implementasinya sangat tergantung dari berbagai hal seperti: Konfigurasi dan Alokasi time slot di level Radio/BTS Teknologi software yang digunakan Dukungan ponsel Ini menjelaskan mengapa pada saat-saat tertentu; di lokasi tertentu; akses GPRS terasa lambat; dan bahkan bisa lebih lambat dari akses CSD yang memiliki kecepatan 9,6 kb/s Jaringan Telekomunikasi

Perbedaan GSM dengan GPRS Jaringan Telekomunikasi

Arsitektur Dasar Jaringan GPRS dalam GSM Jaringan Telekomunikasi

GPRS Architecture Network Diagram Jaringan Telekomunikasi

EDGE Jaringan Telekomunikasi

EDGE Network Jaringan Telekomunikasi

Third Generation Wireless Networks
The aim of third generation wireless networks is to provide a single system that can meet a wide range of applications and provide universal access. The third generation networks will carry many types of information such as voice , data and video and serve both stationary and fixed users. Some of the systems proposed for the third generation systems are CDMA2000 which is backward compatible to systems based on IS 95 and WCDMA which is backward compatible to GSM systems. Jaringan Telekomunikasi

Umts UMTS technology delivers high-speed access to information, , multimedia content, as well as other wireless Internet services through a variety of personal, portable devices Jaringan Telekomunikasi

HIGH DATA RATE & CAPACITY LOW-MED DATA & CAPACITY
The Future of CDMA Services The CDMA2000 family meets the marketplace’s demand for voice and data services. 1xEV-DO CDMA2000 1xEV-DO Peak 2.4 Mbps Packet Data Data Only Services Non Real-time Services 1XEV-DO Rev. A CDMA2000 1xEV-DO Peak 3.1 Mbps Packet Data VoIP and Data Services Real-time Services HIGH DATA RATE & CAPACITY 1xEV-DV CDMA2000 1xEV-DV Peak 3.1 Mbps Data Simultaneous Voice & Data Real-Time Multi-Media Services w/ Attachment Live Video Broadcast S/W Download Music Download Video Conference 1X CDMA2000 1X 2X Voice Capacity Peak Kbps Data Full Web Browsing NON-REAL TIME REAL TIME Interactive Gaming Multi-Media Messaging IS-95 Location Based Services Transaction Based Apps Download Ringers Voice SMS LOW-MED DATA & CAPACITY Adopting technology somewhat like waiting for computer prices to come down?? Jaringan Telekomunikasi

Soal Pada komunikasi seluler yang menggunakan standar GSM, diketahui ukuran cluster 7 dan jumlah kanal radio 70 Berapa faktor reuse? Hitung jumlah kanal suara per sel Jika replikasi 5 kali, berapa kapasitas sistem? Jarak co-channel 41 km, berapa jari-jari sel? Jaringan Telekomunikasi

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