IEEE 802'15 PHY Proposal

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Project IEEE P802.15 Working Group for Wireless
Personal Area Networks (WPANs) Submission Title
PHY Proposal Date Submitted July
2003 Source Ed Callaway Company
Motorola Address 8000 W. Sunrise Blvd,
Plantation, Florida, 33322, USA Voice1 954
723 8341, FAX [phone],
E-Mailed.callaway_at_motorola.com Re IEEE
802.15.4 Abstract This contribution proposes
an alternate PHY for TG4. Purpose To encourage
discussion. Notice This document has been
prepared to assist the IEEE P802.15. It is
offered as a basis for discussion and is not
binding on the contributing individual(s) or
organization(s). The material in this document is
subject to change in form and content after
further study. The contributor(s) reserve(s) the
right to add, amend or withdraw material
contained herein. Release The contributor
acknowledges and accepts that this contribution
becomes the property of IEEE and may be made
publicly available by P802.15.
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Forces on TG4 since the 11/00 PAR-1

• European expansion of 868 MHz band in process
• The Banding Branding Problem Potential market
  confusion between the two existing PHYs difficult
  to overcome may affect investment in the
  industry
• 1 duty cycle of present 868 MHz band limits
  throughput and sleep time with present low data
  rate PHY

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Forces on TG4 since the 11/00 PAR-2

• Additional WPAN applications (consumer remote
  control displaying channel, audio or low
  resolution video capture security systems
  displaying low quality still image capture, 16
  kbps encoded audio for voice recognition remotes,
  PC peripherals, toys, games, and automation and
  control systems) have been identified by ZigBee,
  that cannot be served by the existing 20/40 kb/s
  data rate.
• Chip vendors have informally proposed nonstandard
  dual band chips, using 2.4 GHz modulation
  scheme at 915 MHz, to get higher data rates there.

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Proposal

• Create a new PHY for 802.15.4 that employs the
  2.4 GHz modulation scheme on the 865-868.6 MHz
  and 902-928 MHz bands, but at half the chip rate
• A single 125 kb/s channel centered at 866.8 MHz
  (Channel k 27).
• Ten 125 kb/s channels at 906 2 (k 28) MHz
  (k 28 37, overlaying the existing channels).

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Spectral Plot of 0 dBm 125 kb/s Signal
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Adjacent Channel Spectra
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Features of Our Proposal-1

• A multiband TG4 transceiver becomes much easier
  to build. Such a device could eliminate
  interoperability problems and resulting market
  confusion.
• Users of the 902-928 MHz band get a 3x increase
  in data rate, without a reduction in the number
  of available channels.

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Features of Our Proposal-2

• Advantage is taken of the expanded 868 MHz band,
  giving European users a 6x increase in data rate.
• Economy of scale, greater purchasing leverage via
  reduced sourcing costs, and faster design cycle
  benefits are gained by the OEM.