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.

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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.

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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.

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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.

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IrDA applications

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

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IrDA applications

• Mobile phones e.g. Nokia 6820, SonyEricsson Z600

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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.

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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