Wll

Wireless local loop(wll)

WLL WLL WLL IS A LO CAL COMM UNI CATI ON NETWORK WH ICH IS ES SE NTIALLY A WI RELE SS BAS ED NE TWO RK CAP AB LE OF PR OVI DING US ERS AC CE SS TO ‘P STN’ NE TWORK AND ASS OCI ATE D FACI LI TIES SUP POR TIN G LO CA L LO OP FUNC TI ONALI TIES TO SER VE USE RS WI TH V OICE AN D N ON- VOICE

NEED OF WLL

• Wireline has high installation cost 3035 thousand per line. • Communication with TNF area is very difficult • If subscriber moves to other operator or location investment is wasted • Wireline installation take much time • Wireline not support mobility • Wireline are very much prone to

REQUIREMENTS FOR WLL • SERVICES: support all commercial devices, data transmission, good voice quality. • CAPACITY: 10-10,000 per sq. km • PSTN Connectivity : WLL must integrate seamlessly with the existing PSTN (Public Switch Telephone Network) • Cost

METHODS FOR SUBSCRIBER CONNECTION Exchan ge

Custom er

Copper Local Loop

Architecture of A Typical Wire line Telecom Network Copper Wire

Pillar Copper Cable

Telephone exchange

Pillar

Pillar Copper Wire

WLL CONNECTION Subscrib er

Exchan ge

FS U

BT S

Wireless Local Loop

BS C

WLL SYSTEM corDECT WLL

CDMA – WLL

n

TECHNOLOGY OPTIONS MICRO ARCHITECTURE

MACRO ARCHITECTURE

n GSM CT-2 : CORDLESS TECHNOLOGY-2

:GLOBAL SYSTEM FOR

MOBILE COMMUNICATION n DECT: DIGITAL ENHANCED n DAMPS : DIGITAL ADVANCED MOBILE PHONE SERVIC CORDLESS TECHNOLOGY n CDMA :CODE DIVISION MULTIPLE ACCESS n PHS: PERSONAL HANDIPHONE SERVICE

corDECT WLL The corDECT wireless Access system (WAS) is designed, to provide simultaneous circuit-switched voice and medium-rate internet connectivity at home and office.

Based on the Digital Enhanced Cordless Telecommunication (DECT) Standard

The DECT Standard • Defines the air interface for users. • Specifies the interface between the subscriber terminal and the base stations. • DECT/GSM,DECT/ISDN and DECT/PSTN inter networking profiles •The DECT frequency band is 18801900MHz. •The standard uses 32kbps ADPCM

Main features of corDECT •Good Voice Quality •Simultaneous Voice and Data transmission •Internet upto 70 Kbps •For both urban and rural networks •Rapid deployment of the Access Networks •Does NOT offer mobility •Quick to deploy and expansion •Lost cost effective access technology

corDECT ARCHITECTURE Anten na

Compact Base System 50 line Telecom Network Ex chan g e V5. 2

DIU

MA X. 1000 LI NE S E1int er fac e 200 LI NE S BSD

CBS

Upto 25Km OF C

Base Station Distribution

10 Km depending on LOS

Remote Access Services RAS

CBS

Subscrib er WALLSET

IN TER NET

Range of Transmission Using an omni-directional antenna, one CBS can cover an area with up to 4km The range can be extended to up to 10km (LOS), using directional antenna.

vWallset & Wallset IP: Provide voice connectivity to the subscriber using a RJ-11 interface, enabling one to connect a standard DTMF or decadictelephone, speakerphone, cordless phone, or modem. It also has RS-232 port to connect a PC. PC establishes a dial-up connection. Internet connection is supported a 35 or 70kbps. It has an antenna port. Power is provide by a 12V adaptor. vMultiwallset: Max. four connection

COMPACT BASE • STATION Provide radio interface b\w the DIU • • • • • • •

and corDECT subscriber terminal. Support 12 simultaneous voice call Small, weatherproof unit remotely powered from DIU or BSD Antenna: Directional and Omni-directional depending upon need More then one CBS can serve a single sector or a cell. Max. LOS range 10 km { b\w subscriber and CBS} Multiple CBS’s increase the traffic handled by each CBS CBS is connected to a DIU or BSD with three twisted pair of copper wire for carrying

• DECT Interface Unit: • • • • •

Implement the functions of a switch, Base Station Controller, and Operation and Maintenance Console (OMC). OMC allows exhaustive real-time Monitoring and Management of entire corDECT system. Can support 20 CBS’s, directly or through the BSD. Provide up to 8 E1 link to the telephone network and/or RAS Signaling protocol used V5.2 { DIU-EXCHANGE} OR R2-MF Managed through centralized network management system.

• Base Station Distributor:

Compact, Remotely located, locally powered, rack-mounted unit that supports up to four CBS’s. The E1-interface b\w DIU and BSD on copper, fiber. • Designed to increase coverage

• Each BSD connects to a maximum of four base stations

PSTN

DIU

E1 Link Fibre /Coax/ microwave

BSD

Relay Base Station:

Extend the range of the corDECT system by relaying DECT packets b\w the CBS subscriber unit. high-gain grid antenna for CBS - RBS link UNIT RBS-A

MOUNTED ON A TOWER

GROUND UNIT PROVIDE POWER & PRODUCE MAINTENANCE SUPPORT TO THE AIR UNIT AT MOUNTED

ANTENNAS: Use three antennas One for communicating with CBS referred as RBSWS antennas Other two for communicating with subscriber units, similar to those used by CBS. Max LOS range b\w CBS & RBS is 25 km , 10km b\w RBS & corDECT subscribers

CBS RBS-A

GROUND UNIT

DIU

25 km

WALLSE T 

10 km radius

CDMA WLL system – IS 95

Salient features of cdma wll

ØFR EQ UEN CY BAN D ØRF SPACIN G ØACCES S M ET HO D

ØCOVER AGE

824-849 MHz(up link) 869-894 MHz(down link) 45MHz Code division multiple access In rural- 25km radius In urban-5km radius

CDMA-WLL ARCHITECTURE PSPDN

PSTN BTS

V5.2/R2/No.7 X-25/Q3

BT S

FWT/MS

BSC E1LINK

BSM RS422

CDMA- WLL system IS 95

BASE TRANCEIVER Allocated b\w MS and BSC ( base station controller) SUBSYSTEM:

Perform call control and maintenance function concerning mobile station. Types of BTS: Standard type( for indoor installation and operation) Outdoor type ( for outdoor in installation and operation ) Frequency band: Downlink( BTS II MS): 869-894MHz Uplink ( MS II BTS) : 824-849MHz

BASE STATION CONTROLLER: Located b\w BTS and Public network switching center Applies CDMA digital mobile communication technology, to control 48BTS Provide interface with public network Control call established through the BTS Perform maintenance function for the BTS and BSC

Requirement of the system • Power requirements: DC -43 V to -56 V • Lighting protection • Short circuit protection • Front panel indicator • Duplication requirements • Operation & Maintenance function • Reliability

Physi ca l requirements • Physical configuration: all dimension must meet LGIC document number “TBD” • Cooling

Envi ronme ntal Re quire me nt • Operation Environment +-15c/hr 2-50C 20-60% humidity

Main Function of BSC • • • • • • • • •

Call Control Function Handoff Control Function Transparent Message Transfer Transcoding Function Selecting Function DTMF Tone Conversion IWF for data call Packet routing 1 Call Resource Management

DMA WLL system-2000 1

BS M

HLR

VLR

OMC MSC

BSC

BTS

MSC

M S AuC

um Protocol V-5.2/ R-2no7

abis

A

EIR

S C SME

ARCHITECTURE MSC

r Interface link Budgets CDMA & corDECT WLL

corDECT Enhancement • Improved Sensitivity :