Spectral Allocation Europe USA Japan

Cellular Phones

GSM 450-457, 479-486/460-467,489-496, 890-915/935-960, 1710-1785/1805-1880 UMTS (FDD) 1920-1980, 2110-2190 UMTS (TDD) 1900-1920, 2020-2025

AMPS, TDMA, CDMA 824-849, 869-894 TDMA, CDMA, GSM 1850-1910, 1930-1990

PDC 810-826, 940-956, 1429-1465, 1477-1513

Cordless Phones

CT1+ 885-887, 930-932 CT2 864-868 DECT 1880-1900

PACS 1850-1910, 1930-1990 PACS-UB 1910-1930

PHS 1895-1918 JCT 254-380

Wireless LANs

IEEE 802.11 2400-2483 HIPERLAN 2 5150-5350, 5470-5725

902-928 IEEE 802.11 2400-2483 5150-5350, 5725-5825

IEEE 802.11 2471-2497 5150-5250

Others RF-Control 27, 128, 418, 433, 868

RF-Control 315, 915

RF-Control 426, 868

Evolution of Current Systems

Wireless systems today 2G + 2.5G Cellular: ~30-70 Kb/s. WLANs: ~10 Mb/s.

Next Generation 2.75G + 3G Cellular: ~300 Kb/s. WLANs: ~70 Mb/s.

Technology Enhancements Hardware: Better batteries. Better circuits/processors. Co-

optimization with transmission schemes. Link: Antennas, modulation, coding, adaptivity, DSP, BW. Network: Dynamic resource allocation, Mobility support.

2.5G – Upgrade options GSM

High Speed Circuit Switched Data (HSCSD)

General Packet Radio Service (GPRS) Enhanced Data rate for GSM Evolution

(EDGE) IS-95

IS-95A provides data rates up to 14.4 kbps

IS-95B provides rates up to 64 kbps (2.5G)

3G Vision Universal global roaming Multimedia (voice, data & video) Increased data rates

384 kbps while moving 2 Mbps when stationary at specific locations

Increased capacity (more spectrally efficient) IP architecture Problems

No killer application for wireless data as yet Vendor-driven

CDMA

GSM

TDMA

PHS (IP-Based)

64 Kbps

GPRS

115 Kbps

CDMA 1xRTT

144 Kbps

EDGE

384 Kbps

cdma20001X-EV-DV

Over 2.4 Mbps

W-CDMA (UMTS)

Up to 2 Mbps

2G2.5G

2.75G 3G

1992 - 2000+2001+

2003+

1G

1984 - 1996+

2003 - 2004+

TACS

NMT

AMPS

GSM/GPRS

(Overlay) 115 Kbps

9.6 Kbps

9.6 Kbps

14.4 Kbps/ 64 Kbps

9.6 Kbps

PDC

Analog Voice

Digital Voice

Packet Data

IntermediateMultimedia

Multimedia

PHS

TD-SCDMA

2 Mbps?

9.6 Kbps

iDEN

(Overlay)

iDEN

Source: U.S. Bancorp Piper Jaffray

Migration To 3G

CDMA2000 Pros and Cons Evolution from original Qualcomm CDMA

Now known as cdmaOne or IS-95 Better migration story from 2G to 3G

cdmaOne operators don’t need additional spectrum 1xEVD0 promises higher data rates than UMTS, i.e.

W-CDMA Better spectral efficiency than W-CDMA(?)

Arguable (and argued!) CDMA2000 core network less mature

cdmaOne interfaces were vendor-specific Hopefully CDMA2000 vendors will comply w/ 3GPP2

W-CDMA (UMTS) Pros and Cons Wideband CDMA

Standard for Universal Mobile Telephone Service (UMTS)

Committed standard for Europe and likely migration path for other GSM operators

Leverages GSM’s dominant position Requires substantial new spectrum

5 MHz each way (symmetric) Legally mandated in Europe and elsewhere Sales of new spectrum completed in Europe

At prices that now seem exorbitant

TD-SCDMA Time division duplex (TDD) Chinese development

Will be deployed in China Good match for asymmetrical traffic! Single spectral band (1.6 MHz) possible Costs relatively low

Handset smaller and may cost less Power consumption lower TDD has the highest spectrum efficiency

Power amplifiers must be very linear Relatively hard to meet specifications

Current Wireless Systems Cellular Systems Wireless LANs (802.11a/b/g, Wi-Fi) Satellite Systems Paging Systems Bluetooth Ultrawideband radios (UWB) Zigbee/802.15.4 radios WiMAX (802.16)

Wireless Local Area Networks (WLANs)

WLANs connect “local” computers (~100 m range)

Breaks data into packets Channel access is shared (random access) Backbone Internet provides best-effort

service Poor performance in some app’s (e.g.

video)

01011011

InternetAccessPoint

0101 1011

Wireless LAN Standards (Wi-Fi)

802.11b (Current Generation) Standard for 2.4GHz ISM band (bw 80 MHz) Frequency hopped spread spectrum 1.6-10 Mbps, 500 ft range

802.11a (Emerging Generation) Standard for 5GHz NII band (bw 300 MHz) OFDM with time division 20-70 Mbps, variable range Similar to HiperLAN in Europe

802.11g (New Standard) Standard in both 2.4 GHz and 5 GHz bands OFDM (multicarrier modulation) Speeds up to 54 Mbps

In futureall WLAN cards will have all 3 standards...

HIPERLAN

• Types 1-4 for different user types- Frequency bands: 5.15-5.3 GHz, 17.1- 17.3 GHz

• Type 1- 5.15-5.3 GHz band- 23 Mbps, 20 MHz Channels- 150 foot range (local access only)- Protocol support similar to 802.11- Peer to peer architecture- ALOHA channel access

• Types 2-3- Wireless ATM- Local access and wide area services- Standard under development- Two components: access and mobility support

8C32810.63a-Cimini-7/98

Satellite Systems

Cover very large areas Different orbit heights

GEOs (39000 Km) via MEOs to LEOs (2000 Km) Trade-off between coverage, rate, and power budget!

Optimized for one-way transmission: Radio (e.g. DAB) and movie (SatTV) broadcasting

Most two-way systems struggling or bankrupt... (Too) expensive alternative to terrestrial systems (But: a few ambitious systems on the horizon)

Satellite networks: GEO

Publicnetworks

Gateway

Control station

Publicnetworks

Gateway

Controlstation

Japan SingaporeGEO

Satellite networks: LEO

Publicnetworks

Gateway

Control station

Publicnetworks

Gateway

Controlstation

Japan Singapore

LEO LEOInter-satellite link

Paging Systems Simplex Limited to worldwide coverage possible Broadcast / simulcast Reliable large Txd. Power, Low data

rate

PSTNPagingControlcenter

Pagingtowers

Pagingtowers

Other Wireless Systems Cordless telephone systems

Dedicated Base Station Limited coverage No handoff support

PSTNFixed Base

Station

A general WLL setup

Bluetooth

A new global standard for data and voice Cable replacement RF technology

• Short range (10 meters)• 2.4 GHz band• 1 Data (700 Kbps) and 3 Voice channels • Supported by over 200 telecommunications and computer companies

Goodbye Cables !

Ultimate Headset

Cordless Computer

Automatic Synchronization

In the Office

At Home

Bluetooth Specifications

Connection Type Spread Spectrum (Frequency Hopping)

MAC Scheme FH-CDMA

Spectrum 2.4 GHz ISM

Modulation Gaussian Frequency Shift Keying

Transmission Power 1 mw – 100 mw

Aggregate Data Rate 1 Mbps

Range 30 ft

Supported Stations 8 devices

Voice Channels 3

Data Security- Authentication Key 128 bit key

Data Security-Encryption Key 8-128 bits (configurable)

UltraWideband Radio (UWB)

Impulse radio: sends pulses of tens of picoseconds (10-12) to nanoseconds (10-9) - duty cycle of only a fraction of a percent

Uses a lot of bandwidth (order of GHz)

Low probability of detection by others + beneficial interference properties: low transmit power (density) spread over wide bandwidth

This also results in short range. But : Excellent positioning (ranging) capability + potential of high

data rates

Multipath highly resolvable: both good and bad Can use e.g. OFDM or equalization to get around multipath

problem.

Why is UWB interesting?

Unique Location and Positioning properties 1 cm accuracy possible

Low Power CMOS transmitters 100 times lower than Bluetooth for same range/data rate

Very high data rates possible (although low spectral efficiency) - 500 Mbps at ~10 feet range under current regulations

7.5 Ghz of “free spectrum” in the U.S. FCC (Federal Communications Commission) recently

legalized UWB for commercial use in the US Spectrum allocation overlays existing users, but allowed

power level is very low, to minimize interference “Moore’s Law Radio”

Data rate scales with the shorter pulse widths made possible with ever faster CMOS circuits

IEEE 802.15.4/ZigBee radios

Low-Rate WPAN (Wireless Personal Area Network) - for communications < 30 meters.

Data rates of 20, 40, 250 kbps Star topology or peer-to-peer operation, up to 255

devices/nodes per network Support for low-latency devices CSMA-CA (carrier sense multiple access with collision

avoidance) channel access Very low power consumption: targets sensor networks

(battery-driven nodes, lifetime maximization) Frequency of operation in ISM bands

WiMAX: Worldwide Interoperability for Microwave

Access

Standards-based (PHY layer: IEEE 802.16 Wireless MAN family/ETSI HiperMAN) technology, enabling delivery of ”last mile” (outdoor) wireless broadband access, as an alternative to cable and DSL (MAN = Metropolitan Area Network). Several bands possible.

OFDM-based adaptive modulation, 256 subchannels. TDM(A)-based. Antenna diversity/MIMO capability. Advanced coding + HARQ.

Fixed, nomadic, portable, and mobile wireless broadband connectivity without the need for direct line-of-sight (LOS) to base station.

In a typical cell radius deployment of 3 to 10 kms, expected to deliver capacities of up to 40 Mbps per channel, for fixed and portable access.

Mobile network deployments are expected to provide up to 15 Mbps of capacity within a typical cell radius deployment of up to 3 kms.

WiMAX technology already has been incorporated in some notebook computers and PDAs. Potentially important part of 4G?

Data rate

10 kbits/sec

100 kbits/sec1 Mbit/sec

10 Mbit/sec

100 Mbit/sec

0 GHz 2 GHz1GHz 3 GHz 5 GHz4 GHz 6 GHz

802.11a

UWBZigBee

Bluetooth

ZigBee

802.11b

802.11g

3G

UWB

Frequencies occupied

Range

1 m

10 m

100 m

1 km

10 km

0 GHz 2 GHz1GHz 3 GHz 5 GHz4 GHz 6 GHz

802.11a

UWB

ZigBee BluetoothZigBee

802.11b,g

3G

UWB

Power Dissipation

1 mW

10 mW

100 mW

1 W

10 W

0 GHz 2 GHz1GHz 3 GHz 5 GHz4 GHz 6 GHz

802.11a

UWB

UWBZigBee

Bluetooth

ZigBee

802.11bg3G

Emerging Systems Ad hoc wireless networks Sensor networks Distributed control networks

Ad-Hoc Networks

Peer-to-peer communications. No backbone infrastructure (no base stations). i.e. “Truly wireless”! Routing can be multihop. Topology is dynamic in time; networks self-organize. No centralized cooordination. Fully connected, even with different link SINRs (signal-

to-interference plus noise ratios)

Sensor NetworksEnergy is the driving constraint

Nodes typically powered by nonrechargeable batteries. Data (sensor measurements) flow to one centralized location (sink node,

data fusion center). Low per-node rates - but up to 100,000 nodes. Sensor data highly correlated in time and space. Nodes can cooperate in transmission, reception, compression, and signal

processing.

Energy-Constrained Nodes Each node can only send a finite number of bits.

Transmit energy minimized by maximizing bit time Circuit energy consumption increases with bit time Introduces a delay versus energy tradeoff for each bit!

Short-range networks must consider transmit, circuit, and processing energy - jointly.

Most sophisticated transmission techniques not necessarily most energy-efficient!

Sleep modes save energy - but complicate networking.

Changes everything about the network design: Bit allocation must be optimized across all protocols. Delay vs. throughput vs. node/network lifetime

tradeoffs. Optimization of node cooperation.