1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Narrow Band PHY Proposal for g]
Date Submitted: [27 February 2009]
Source:
[Cristina Seibert] Company [Silver Spring Networks]
[Benjamin A. Rolfe] Company [Blind Creek Associates]
[George Flammer] Company [Silver Spring Networks]
Address [] Voice:[]
silverspringnet.com] blindcreek.com] silverspringnet.com]
Re: []
Abstract: Preliminary Proposal for a Narrow Band PHY for g
Purpose: Technical Proposal
Notice: This document has been prepared to assist the IEEE P 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 P

2. Narrow-band PHY Proposal for 802.15.4g
<month year>
doc.: IEEE <doc#>
January 1, 2019
Smart Utility Networks
(SUN)
Narrow-band PHY Proposal for g
Preliminary Technical Features Summary
<author>, <company>

3. PHY Overview Contents Key Characteristics of SUN General PHY Features
January 1, 2019
PHY Overview Contents
Key Characteristics of SUN
General PHY Features
Key PHY Techniques
Hopping and Modulation
Data Whitening
PHY Processing Aspects
Data Transfer
PHY Frame (PPDU)
PHY Channel Plan
MAC Support

4. Key Characteristics of SUN
January 1, 2019
Key Characteristics of SUN
Some of the characteristics of the W-SUN include:
Low data rate: over the air data rates of 40kb/s up to 1 Mb/s
High resilience and adaptability in the presence of interference and good coexistence properties with both like systems and non SUN systems.
Enhanced IP support (> 1500 octet payload)
Ubiquity
Very high reliability and availability
Dynamic scaling to very large aggregate networks
Peer to Peer, minimal infrastructure-dependent operation
PHY
MAC

5. General PHY Features Frequency Hopping Spread Spectrum:
January 1, 2019
General PHY Features
Frequency Hopping Spread Spectrum:
Individual channels at nominal < 250 KHz, 20 dB down from peak
300 KHz channel spacing
Channel plan across multiple bands
Simple PHY frame
Support for 2047 octet payload (802.1 MTU)
w/32-bit CRC on PHY payload (802 standard generator)
Nominal (base)100kbps data rate, alternate rates possible
Simple FSK modulation
Data whitening of payload bits

6. Hopping and Modulation
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Hopping and Modulation
FHSS:
A method of transmitting radio signals
Carrier tunes to various channels
Channel pseudorandom sequence known to both transmitter and receiver.
FSK:
A frequency modulation scheme
Digital information is transmitted through discrete frequency changes of a carrier wave.
MFSK is a spectrally efficient form of FSK.

7. January 1, 2019
Data whitening
Whitens payload data (PSDU/MPDU) to avoid long series of 1’s and 0’s.
8-bit scrambler (255 bit sequence)
taps at bits [8,4,3,2]
Scrambler re-seeded periodically

8. PHY Processing Aspects
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PHY Processing Aspects
The physical layer (PHY) provides the on-air interface between communicating nodes. Its header is sent “in the clear” and its payload (the MAC/DLL data) is scrambled by the PHY Layer.
The major functions of the PHY layer is the recovery of bit timing, determination of start-of-frame, recovery of the scrambling seed, and length of the PHY frame, and performing a 32-bit cyclic-redundancy-check against the unscrambled MAC/DLL data field.
The PHY layer then processes the incoming stream for length bytes, calculating the CRC-32. If the CRC-32 matches that received, the PHY layer passes the frame to the MAC/DLL for subsequent processing.

9. January 1, 2019
Data Transfer

10. PHY Frame (PPDU) Support for 2047 octet payload (802.1 MTU)
January 1, 2019
PHY Frame (PPDU)
Support for 2047 octet payload (802.1 MTU)
IEEE CRC-32 on PHY frame
Octets: 7 2 1
variable 4
Bits: 56 16 8 11 32
Preamble
SFD
Scrambler Seed R F U E X T
Length
(PSDU)
CRC-32
SHR
PHR
PHY Payload
FCS
Structure of PPDU

11. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
January 1, 2019
PHY Channel Plan
Large number of narrow band channels across multiple bands
Hop-able across all bands implemented
At least one band from:
MHz (China)
840 to 956 MHz
868–868.6 MHz (e.g. Europe, China, others)
902–928 MHz (e.g., Americas, China, others)
MHz (Japan) ,
2400– MHz (worldwide)
Other bands available?
<author>, <company>

12. PHY Channel Plan Band # Chans 902–928 MHz 85 2400–2483.5 MHz 277
January 1, 2019
PHY Channel Plan
Increase channels per page to support more channels
Band
# Chans
902–928 MHz 85
2400– MHz
277
MHz 19 12 5 1

13. PHY Channel Plan . Example: 902–928 MHz
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PHY Channel Plan
Example: 902–928 MHz
Chan n: (n*0.3) where n=0 to 84 0: 1: 2: 3: 4: 5: 6: 7: 8: 9:
10:
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19: .
63:
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67:
68:
69:
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76:
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83:
84:

14. MAC Support Meet regulatory requirements for channel occupancy
January 1, 2019
MAC Support
Meet regulatory requirements for channel occupancy
E.g. max on channel 0.4 seconds
Visit each channel in sequence before re-visiting
OK to skip channel (black-listing)
Reliability support
Packet acknowledgment
Packet retransmission