STRUKTUR JARINGAN PLMN

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STRUKTUR JARINGAN PLMN

• Program S1 Teknik Telekomunikasi
• Jurusan Teknik Elektro
• STT Telkom

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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
  1990. 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

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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 - 800 - 900 MHz and 400 - 500
  MHz
• 120 kHz RF bandwidth with channel spacing of 30
  kHz
• Data rate 5 - 10 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

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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 800 - 900 MHz and 400 - 500 MHz
• Channel spacing 30 kHz and no of channels 400
  -1000
• Data rate 5 - 10 kbps
• FM for speech, FSK for signaling, FDM

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History - 2nd Generation (2G)Systems (1991-2)

• Systems
• 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 band _at_ 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)

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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
• 2000 - 2nd Transitional Systems 2.5 GHz
• 2001 - 1st CDMA Network _at_ 144 k bps
• 2002- Handover between GSM and WCDMA

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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

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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)

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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

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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.

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Model pola radiasi
R
R
R
R
R

• Model radiasi mana yang paling bagus ?

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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 
                
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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
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Perbandingan PSTN dan PLMN
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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
  (OM)
• Elemen jaringan untuk signaling
• Elemen jaringan untuk transport dan transmisi
• Note pada bab ini diberikan contoh untuk
  jaringan GSM

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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).

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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.

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• 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).

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What happens when a cellular user turns on their
phone?
Terminal scans control channels and locks on to
strongest one. If cant find a strong enough
signal, no service With receiver turned to
strongest control channel, terminal extracts
important information from broadcast channel.
Strongest Signal
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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
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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 terminals 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.
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Masalah dalam jaringan seluler

1. Number of Channels Per Cell
2. Fading
3. Co-Channel Interference
4. Handovers
5. Multiple access

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Masalah dalam jaringan seluler
Number of Channels Per CellWhen 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.            SolutionUse a
microcellular network since it can increase the
number of channels per cell without an increase
in co-channel interference
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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

SolutionThe 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
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Masalah dalam jaringan seluler
Co-Channel InterferenceCo-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.            SolutionHere,
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.
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Masalah dalam jaringan seluler

• HandoversHandover 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.

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Masalah dalam jaringan seluler

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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
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1 G
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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

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2G
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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.

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GSM
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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

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Architecture of the GSM network
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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

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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.

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Mobile station

• Merupakan terminal transceiver
• Diidentifikasikan dengan IMEI tertentu
• IMEI International Mobile Equipment Identity
• MS terdiri dari
• Mobile Equipment (ME)/HP
• Subscriber Identification Module (SIM)

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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

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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

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BTS
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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

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BSC
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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)

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Network Sub-system (NSS)
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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
mobiles supplementary services. Maintains a
register of visitors operating within the
coverage area of the MSCs 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.
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Network elements as databases

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

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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.

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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

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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.

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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.

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Operation Sub-system (OSS)

• Operation dan Maintenance Jaringan
• Pengaturan pelanggan dan tagihan
• Pengaturan Mobile Equipment

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Interface

• Antara BTS dan BSC dihubungkan oleh Abis
  interface
• BTS berkomunikasi dengan MS dengan Um interface

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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

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Konsep Kanal GSM
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Traffic channels
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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

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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

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Timing Advance Control
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Hirarki Kanal Logic GSM
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Signal Processing in GSM
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Data Service in GSM
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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.

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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).

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2.5G

• GPRS, EDGE

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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

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Perbedaan GSM dengan GPRS
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Arsitektur Dasar Jaringan GPRS dalam GSM
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GPRS Architecture Network Diagram
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EDGE
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EDGE Network
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3G
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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.

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Umts
UMTS technology delivers high-speed access to
information, email, multimedia content, as well
as other wireless Internet services through a
variety of personal, portable devices
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The Future of CDMA Services
The CDMA2000 family meets the marketplaces
demand for voice and data services.
HIGH DATA RATE CAPACITY
E-MAIL w/ Attachment
Live Video Broadcast
S/W Download
Video Conference
Music Download
Full Web Browsing
NON-REAL TIME
Interactive Gaming
REAL TIME
E-MAIL
Multi-Media Messaging
Location Based Services
IS-95
Transaction Based Apps
Download Ringers
Voice
SMS
LOW-MED DATA CAPACITY
Adopting technology somewhat like waiting for
computer prices to come down??
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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?