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WPAN standards, applications

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Title: WPAN standards, applications


1
WPAN standards, applications market overview
  • 83180 WIRELESS LANS
  • Kari Juopperi, kari.juopperi_at_tut.fi
  • Rami Juvonen, rami.juvonen_at_tut.fi

2
Contents
  • Introduction
  • HomeRF
  • DECT
  • IrDA
  • Comparison
  • Conclusion
  • References

3
Introduction
  • WPAN is very similar to WLAN in terms of its
    functional goals.
  • Main differences are
  • power consumption
  • device cost
  • device communication distance
  • network lifespan
  • device size
  • easy to use / to join the network

4
Introduction
  • WPAN technology aims to develop a smart
    home/office interworking.
  • Besides IEEE related products (Bluetooth,
    Zigbee), there are competing products available
  • HomeRF
  • DECT
  • ETSI HIPERLAN
  • IrDA

5
HomeRF
  • The Home Radio Frequency Working Group (HomeRF
    WG) was formed by a number of large PC
    stakeholders.
  • The HomeRF Working Group developed a single
    specification (Shared Wireless Access
    Protocol-SWAP).
  • The SWAP specification provides low cost voice
    and data communications in the 2.4GHz ISM band.

6
HomeRF protocol design
7
HomeRF SWAP relation
  • SWAP system can operate in two modes
  • ad hoc approach
  • managed network approach
  • SWAP network doesnt require access points. -gt
    cheaper network infrastructure.
  • The most current SWAP 2.0 implementation gives
    10Mbits maximum throughput.

8
HomeRF layer model
  • SWAP protocol stack uses other protocols such as
    DECT
  • SWAP specification has data paths for media and
    for voice data.

9
HomeRF bandwidth utilization
  • If there are no voice connections and no
    multimedia present on network, the full bandwidth
    is available for data.
  • Automatic priorization shares bandwidth as
    needed. Usually voice gets half and data gets
    other half. Multimedia streams have the lowest
    priority.

10
HomeRF MAC layer
  • The link layer of SWAP uses both TDMA and CSMA/CA
    access.
  • Security is provided by 24-bit network ID,
    network password and frequency hopping.

11
HomeRF physical layer
  • Transmit power up to 24 dBm
  • FSK (Frequency Shift Keying) modulation is used.
  • Optional low power transmit mode 0 to 4 dBm for
    portable devices.
  • Frequency hopping is used for finding a carrier
    with the best possible quality. (hopping time
    300 µs)

12
HomeRF applications
  • Example application Proxim Symphony HomeRF
    Cordless Gateway 4930
  • Can work as
  • wireless router
  • wireless-to-ethernet bridge
  • both

13
HomeRF applications
14
HomeRF applications
  • Example application Motorola Simplefi.
  • Connects PC and stereo system using HomeRF USB
    transmitter on PC.
  • Launched in 2002 with a price 379, nowdays very
    outdated idea.

15
HomeRF marketview
16
HomeRF future?
  • In the year 2000, HomeRF Working Group claimed
    that HomeRF had gained over 90 share of the
    wireless home networking market.
  • In 2001 however, 802.11b stole the markets almost
    completely.
  • The HomeRF Working Group disbanded January 2003.
  • Manufacturers dont support HomeRF/SWAP anymore.

17
DECT
  • DECT (Digital Enhanced Cordless
    Telecommunication) standard defines a general
    radio access technology for wireless
    telecommunications.
  • DECT is operating in 1880-1900 Mhz band using
    GFSK modulation.
  • Supporting numerous different application
    technologies such as PSTN, ISDN, GSM, LAN, fax,
    modem, X.25

18
DECT
  • ETSI has developed the DECT standard.
  • DECT base standard only covers the air
    interface between a DECT Fixed Part (FP) and a
    DECT Portable Part (PP).
  • DECT makes available the network specific
    services and features to the user through the
    DECT common air interface transparently.

19
DECT
  • Multi Carrier, Time Division Multiple Access,
    Time Division Duplex (MC/TDMA/TDD) radio access
    method is used.

20
DECT
  • High capacity is provided by Dynamic Channel
    Selection and Allocation capability.
  • Excellent Quality of Service (without the need of
    frequency planning) -gt DECT makes efficient use
    of the assigned radio spectrum.

21
DECT security
  • Subscription, authentication and cyphering
    provide protection against unauthorized access
    and eavesdropping.
  • Subscription procedure
  • Service provider provides a secret subscription
    key, that will be entered to fixed and portable
    part.
  • Handset and network identities are exchanged, and
    both sides calculate a secret authentication key.

22
DECT authentication
  • 1. Base station sends a random number to the
    handset (challenge).
  • 2. The handset calculates response from random
    number and auth. key
  • 3. The base station calculates expected response
    and compares it to received response.

23
DECT applications
  • Example application Siemens Gigaset.
  • Extra long talk time up to 15 hours
  • Perfect timing with countdown timer
  • SMS with up to 640 characters
  • Polyphonic ringer melodies
  • Comfortable handsfree function
  • CLIP function displays callers name
  • Phonebook for up to 100 entries

24
DECT applications
  • Plantronics CS60 wireless headset
  • range 100m in free space, 50m in office
  • DECT used between an USB base station and
    headset.
  • Can be used with normal and VoIP calls.

25
DECT markets
  • DECT handsets and Base Stations have been on the
    market since 1993.
  • GAP compliant DECT equipment became available
    1996.

26
DECT future
  • Work is ongoing to further improve the data
    capabilities of DECT and to increase the quality
    of high bit rate transmissions (20Mbit/s).
  • Development of dual mode terminals supporting
    both DECT and GSM.
  • The future of DECT seems very bright.

27
IrDA
  • IrDA (Infrared Data Association) is a standard
    defined by IrDA consortium.
  • Specification includes standards defined for both
    physical and upper layers.
  • IrDA devices communicate using infrared LEDs
    with a wavelength 875 30 nm.

28
IrDA v.1.0
  • Speed range from 2400 to 115200 bps.
  • Data format similar to serial port transaction
    (UART frame).
  • Working distance 1,0 m with BER 10-9.
  • Pulse modulation with 3/16 of the length of the
    original duration of a bit is used.

29
IrDA v.1.1
  • Speed range from 0,576 to 1,152 Mbps.
  • Addressing and CRC-16 checksum are added to data
    frame.
  • Pulse modulation with 1/4 of the length of the
    original duration of a bit is used.

30
Other IrDA standards
  • 4 Mbps version (4PPM modulation, ¼ mark to space
    ratio, more advanced CRC-32 checksum).
  • IrDA v.1.2 (low power), max speed 115 kbps,
    working distance 20 cm.
  • IrDA Control (for controlling devices), max speed
    75 kbps, working distance 5 m.
  • IrTran-P (Infrared Transfer Picture) is used in
    digital cameras.

31
IrDA applications
  • HP 200LX Palmtop
  • Year model 1995 (one of the first applications).
  • IrDa used in printing software.

32
IrDA applications
  • Mobile phones e.g. Nokia 6820, SonyEricsson Z600

33
IrDA markets future
  • There was over 64 million IrDA compliant devices
    in 2003.
  • IrDA is still very active technology, it works
    fine when there is no need for long working
    distance and fast transfer speed.
  • Its cheap to implement.

34
Comparison
35
Comparison results
  • DECT delivers good performance, but its mainly
    suitable for voice transmission.
  • HomeRF delivers good figures, but its a dying
    technique.
  • Bluetooths ability to form ad hoc networks
    without infrastructure, with power management and
    voice capabilities makes it ideal for WPAN.

36
Conclusion
  • HomeRF is technically advanced, but not supported
    by manufacturers anymore.
  • DECT is used in many recent applications.
  • IrDA is still widely used despite of its age.
  • Bluetooth is the leading technology for common
    data transfer in WPANs. It continues to conquer
    markets from IrDA.

37
References
  • Aurangzaib Kaleem Wireless Personal Area
    Networking Systems A Comparison of Bluetooth,
    IrDA Data and HomeRF
  • DECT Forum DECT The Standard explained
  • http//www.broadcastpapers.com/data/IBCMotorolaHom
    eNetwork03.htm
  • http//www.informit.com/articles/
  • http//www.hw.cz/english/docs/irda/irda.html
  • http//www.palowireless.com
  • http//www.nokia.fi
  • http//www.sonyericsson.fi
  • http//www.extremetech.com/article2/0,1558,1157779
    ,00.asp
  • http//www.erifon.fi/cs60/CS60_ProducSheet.pdf
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