Perspectives in risk management in Italy: the impact of WiMAX and WiFi Dr. Ing. M. Mozzo, Dr. Ing. F. Boella, Dr. Ing. F. Panin, Prof. L.Giuliani Istituto.

Perspectives in risk management in Italy:Perspectives in risk management in Italy: the impact of WiMAX and WiFi the impact of WiMAX and WiFi

Dr. Ing. M. Mozzo, Dr. Ing. F. Boella, Dr. Ing. F. Panin, Prof. L.GiulianiDr. Ing. M. Mozzo, Dr. Ing. F. Boella, Dr. Ing. F. Panin, Prof. L.Giuliani

Istituto Superiore per la Prevenzione e la Sicurezza del LavoroIstituto Superiore per la Prevenzione e la Sicurezza del Lavoro

17/12/0717/12/07

SummarySummary What is Wi-Fi?What is Wi-Fi? What is WiMAX?What is WiMAX? Wi-MAX Wi-MAX tendertender in Italy in Italy capacity of WIMAXcapacity of WIMAX WIMAX scenarioWIMAX scenario another scenarioanother scenario increasing the frequency ...increasing the frequency ... bibliographybibliography

What is Wi-Fi?What is Wi-Fi?

Stands for Wireless Fidelity (1997)Stands for Wireless Fidelity (1997) Wireless network extension ofWireless network extension of already already

existent successful Ethernet LAN.existent successful Ethernet LAN. 2,4 GHz 2,4 GHz FreeFree frequency band with limited frequency band with limited

power emission.power emission. Multiple Access with collision avoidance.Multiple Access with collision avoidance. prone to interference signals by other prone to interference signals by other

access-point access-point DS and FH Spread-spectrum modulation and DS and FH Spread-spectrum modulation and

OFDM multiplexingOFDM multiplexing Portable and mobile stationsPortable and mobile stations

Wi-Fi Cell coverage and throughput Wi-Fi Cell coverage and throughput (declared by manufacturer )(declared by manufacturer )

Access Point (Outdoor)Access Point (Outdoor) Frequency bands: 100 MHz near 2.4 and 5.7 Frequency bands: 100 MHz near 2.4 and 5.7

GHzGHz Transmit Power: up to 100 mW (20 dBm)Transmit Power: up to 100 mW (20 dBm) Minimum useful signal : Minimum useful signal :

-94 dBm (1 Mbps) -94 dBm (1 Mbps) ÷ -72 dBm (54 Mbps)÷ -72 dBm (54 Mbps) Throughput and range:Throughput and range:

• 54 Mbps 54 Mbps 4545÷60 m÷60 m• 11 Mbps11 Mbps 190÷235 m190÷235 m

Antenna gain at access point : 5 ÷ 13 dBiAntenna gain at access point : 5 ÷ 13 dBi

Impact of Wi-Fi to radio environmentImpact of Wi-Fi to radio environment

● The scenario is going to be The scenario is going to be hot-hot-spotted isolated coveragespotted isolated coverage with with 100mW at 2,4GHz100mW at 2,4GHz

● unlicensedunlicensed ISM bands (industrial, ISM bands (industrial, scientific medical) scientific medical)

● freely maintained by local freely maintained by local administratorsadministrators

● in public areas (airport, train station, in public areas (airport, train station, office, school park, etc.)office, school park, etc.)

What is WiMAX?What is WiMAX?

Stands for World-wide Interoperability for Stands for World-wide Interoperability for Microwave Access.Microwave Access.

also known as Wi-fi maximizedalso known as Wi-fi maximized

The industry trade group WiMAX ForumTM The industry trade group WiMAX ForumTM has defined WIMAX as the “last mile” has defined WIMAX as the “last mile” broadband wireless access (BWA) broadband wireless access (BWA) alternative to ADSL service. alternative to ADSL service.

specificationsspecifications

2004 Air Interface for 2004 Air Interface for FixedFixed Broadband Broadband Wireless Access Systems (IEEE 802.16) Wireless Access Systems (IEEE 802.16) whose primary bands of interest are 10-66 whose primary bands of interest are 10-66 GHz, where line-of-sight (LOS) is necessary GHz, where line-of-sight (LOS) is necessary and multipath negligible.and multipath negligible.

Frequency below 11GHz provide a physical Frequency below 11GHz provide a physical environment where, due to longer environment where, due to longer wavelength, LOS is not necessary and wavelength, LOS is not necessary and multipath may be significant. multipath may be significant.

many physical layer specifications (PHY)many physical layer specifications (PHY)

specification (specification (continuedcontinued)) The ability to support near-LOS and non-LOS The ability to support near-LOS and non-LOS

(NLOS) scenarios requires additional (NLOS) scenarios requires additional functionality, such as the support of advanced functionality, such as the support of advanced power management techniques, interference power management techniques, interference mitigation/coexistence and multiple antennas mitigation/coexistence and multiple antennas

the wirelessMAN-OFDM is based on OFDM the wirelessMAN-OFDM is based on OFDM modulation and designed for NLOS operations in modulation and designed for NLOS operations in the frequency bands below 11GHz the frequency bands below 11GHz

2005 2005 MobileMobile amendment (IEEE 802.16e) . amendment (IEEE 802.16e) .

some technical detailssome technical details At 3,5GHz, wavelength is 8cm and radioAt 3,5GHz, wavelength is 8cm and radiowave can wave can

reach 50Km, pass through trees and rain (drizzle). reach 50Km, pass through trees and rain (drizzle). Robust narrow-band modulations (QPSK,QAM)Robust narrow-band modulations (QPSK,QAM) ~~100 sub-carrier100 sub-carrier frequency or time duplexing frequency or time duplexing

Wi-MAX Wi-MAX tender in Italy in Italy Published on 19th October 2007 Published on 19th October 2007

To licence the use of frequency bands To licence the use of frequency bands allocated at 3.5 GHz using allocated at 3.5 GHz using Broadband Broadband Wireless Access (BWAWireless Access (BWA) systems ) systems

Constrains to radio emissions (Maximum Constrains to radio emissions (Maximum EIRP and Block Edge Mask as usual) inEIRP and Block Edge Mask as usual) in Raccomandazione n. ECC/REC(04)05Raccomandazione n. ECC/REC(04)05

48 48 applicantsapplicants

Possible applications of Wi-MAXPossible applications of Wi-MAX Besides “last mile” broadband wireless access Besides “last mile” broadband wireless access

in rural areas to overcome the digital divide, in rural areas to overcome the digital divide, possible application are:possible application are:

• fixed telephony competitor fixed telephony competitor

• mobile telephony competitormobile telephony competitor

• Transport network (backhaul) competitorTransport network (backhaul) competitor of of radio links or fibre between Wi-fi access points radio links or fibre between Wi-fi access points or mobile telephony towers or mobile telephony towers

Tipical Cell coverage and throughput Tipical Cell coverage and throughput (declared goals)(declared goals)

10Km NLOS point-to-multipoint 40Mbps to 10Km NLOS point-to-multipoint 40Mbps to mobile, portable and fixedmobile, portable and fixed

50Km LOS point-to-point 72Mbps to 50Km LOS point-to-point 72Mbps to portable and fixed onlyportable and fixed only..

anyway these features become of second anyway these features become of second order as far as regards maximizing order as far as regards maximizing subscribers => capacity constrains. subscribers => capacity constrains.

capacity of WIMAXcapacity of WIMAX

(2+1)x2 frequency bands of 21MHz(2+1)x2 frequency bands of 21MHz adaptable bit/symbol depending by adaptable bit/symbol depending by

radio-path impairments (one symbol radio-path impairments (one symbol can use manycan use many carriers) carriers)

Telco operators usually makes Telco operators usually makes maximum use of limited spectrum maximum use of limited spectrum assets => cellular systemassets => cellular system

WIMAX scenarioWIMAX scenario Telco operators could Telco operators could

implement a cellular implement a cellular system to substitute system to substitute telephone copper telephone copper wire to subscriber wire to subscriber home, system that home, system that resembles the resembles the already existent one already existent one for the mobile for the mobile telephonytelephony

system profilesystem profile

example of an example of an implementation implementation casecase

Antennas, receivers, Antennas, receivers, powers, radio paths powers, radio paths and above all and above all interference are interference are almost the same as almost the same as GSM mobile scenarioGSM mobile scenario

another scenarioanother scenario Telco operators could Telco operators could

provide broadband provide broadband wireless access in rural wireless access in rural areasareas

paraboloidal antenna can paraboloidal antenna can be used even though at be used even though at 3,5GHz they are not so 3,5GHz they are not so well performing (with a well performing (with a diameter of 80cm=>only diameter of 80cm=>only 25dB gain, beamwidth 25dB gain, beamwidth 10° )10° )

Rabio base-subscriber Rabio base-subscriber home radio channel home radio channel resembles a radio link resembles a radio link

increasing the frequency ...increasing the frequency ... Operators could reuse the spectrum deploying Operators could reuse the spectrum deploying

the narrow beam of very directional antennas the narrow beam of very directional antennas (paraboloidal) from a high tower(paraboloidal) from a high tower

In this case also the user antenna should be In this case also the user antenna should be paraboloidal => fixed (not mobile)paraboloidal => fixed (not mobile)

In this scenario, a narrow beam covers a In this scenario, a narrow beam covers a village from a distant high tower. village from a distant high tower.

Link budget example for DL mobile WiMAXLink budget example for DL mobile WiMAX

Total TX Power: 20 WTotal TX Power: 20 W

Power used for link budget: 10 WPower used for link budget: 10 W

Penetration Loss: 15 dBPenetration Loss: 15 dB

Minimum useful signal : -75 dBm (68 dBMinimum useful signal : -75 dBm (68 dBµV/m)µV/m)

UMTS tech overviewUMTS tech overview

Frequency bands: Frequency bands:

19201920÷÷1980 MHz (UL) and 21101980 MHz (UL) and 2110÷÷2170 MHz (DL)2170 MHz (DL)

Max number of (voice) channels on 2x5MHz: ~196

Max user data rate offered: 2 Mbps (DL)Max user data rate offered: 2 Mbps (DL)

Antenna directional gain: 17÷18.5 dBiAntenna directional gain: 17÷18.5 dBi

Link budget example for DL UMTSLink budget example for DL UMTS

Total sector TX Power: 43 dBm (20 W)Total sector TX Power: 43 dBm (20 W)

PPCPICHCPICH= 33 dBm (2 W) = 33 dBm (2 W)

Penetration Loss: 15 dBPenetration Loss: 15 dB

Minimum useful signal: -78 dBm (66 dBMinimum useful signal: -78 dBm (66 dBµV/m)µV/m)

Ray-tracing simulation technique:Ray-tracing simulation technique:Quick_PlanQuick_PlanTM TM by TeSby TeS

Full 3D ray-tracingFull 3D ray-tracing Integrated Geographical Information Integrated Geographical Information

System (GIS)System (GIS) Oracle DBMSOracle DBMS Integrated 3D cartography Integrated 3D cartography

(terrain + buildings)(terrain + buildings)

UMTS coverageUMTS coverage

UMTS far-field expositionUMTS far-field exposition

WiMAX coverageWiMAX coverage

WiMAX far-field expositionWiMAX far-field exposition

bibliographybibliography ANSI/IEEE Std 802.11, 1999 Edition (R2003) Part 11: Wireless ANSI/IEEE Std 802.11, 1999 Edition (R2003) Part 11: Wireless

LAN Medium Access Control (MAC) and Physical Layer (PHY) LAN Medium Access Control (MAC) and Physical Layer (PHY) SpecificationsSpecifications

Cisco Aironet Antennas and AccessoriesCisco Aironet Antennas and Accessories IEEE standard 802.16-2004 Part16:Air Interface for fixed IEEE standard 802.16-2004 Part16:Air Interface for fixed

broadband wireless Access Systembroadband wireless Access System Eklund: IEEE standard 802.16: “A technical overwiev of he Eklund: IEEE standard 802.16: “A technical overwiev of he

wirelessMAN air interface for broadband wireless access” wirelessMAN air interface for broadband wireless access” June 2002June 2002

Webb : Broadband fixed wireless access as a key component Webb : Broadband fixed wireless access as a key component of the future integrated communication environment 2001of the future integrated communication environment 2001