Jul 12, 2010 07/12/10 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: Extension of the 802.15.4 OFDM PHY for utility applications Date Submitted: Sept 2017 Source: Benjamin A. Rolfe (Blind Creek Associates), Matthew Gillmore (Itron), Tim Godfrey (EPRI), Clint Powell (PWC/Utilities) Contact: Voice: +1 408 395 7207, E-Mail: ben.rolfe@ieee.org Re: Wireless Next Generation, Suggested enhancements to 802.15.4 Abstract: Presents requirements derived from utility networking experience which suggest modestly higher data rates for certain applications, and suggests simple enhancement to the existing standard to address these requirements. Purpose: Stimulate thought and identify potential enhancements. 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. Page 1

Introduction Requirements derived from utility use cases Input from multiple utilities Input from experienced vendors Focus on enhancing/extending technologies and topologies which have been successful

Repeating Themes Utilities are asking for higher data rates Require lower latency in mesh networks to support latency sensitive applications <10ms per hop required in some applications Applications with higher data volumes e.g. OTA updates. Higher capacity of nodes in mesh networks Expanding trade-off space for balancing bandwidth, interference footprint, delivery reliability. Performance: Higher Rates & Adaptive RF link optimization Mix of performance needs Minimize Latency, effective use of spectrum, backward compatibility Ability to adjust to changing RF conditions

Points to increases in data rates Modest increases – still low Mb/sec Modest bandwidth usage/channel width Flexible channelization Just Right balancing point OFDM 800 kbps, 1.2 Mbps, 2.4 Mbps Compliment to lower rate (bandwidth) OFDM and FSK Builds on what is working now

Current OFDM options and MCS Parameter OFDM Option 1 OFDM Option 2 OFDM Option 3 OFDM Option 4 Nominal bandwidth (kHz) 1094 552 281 156 Channel spacing (kHz) 1200 800 400 200 DFT size 128 64 32 16 Active tones 104 52 26 14 # Pilot tones 8 4 2 # Data tones 96 48 24 12 MCS0 (kb/s) (BPSK rate 1/2 with 4x frequency repetition) 100 50 — MCS1 (kb/s) (BPSK rate 1/2 with 2x frequency repetition) MCS2 (kb/s) (QPSK rate 1/2 and 2x frequency repetition) MCS3 (kb/s) (QPSK rate 1/2) MCS4 (kb/s) (QPSK rate 3/4) 600 300 150 MCS5 (kb/s) (16-QAM rate 1/2) MCS6 (kb/s) (16-QAM rate 3/4)

Example of obvious extension Parameter OFDM Option 1 OFDM Option 2 OFDM Option 3 OFDM Option 4 Nominal bandwidth (kHz) 1094 552 281 156 Channel spacing (kHz) 1200 800 400 200 DFT size 128 64 32 16 Active tones 104 52 26 14 # Pilot tones 8 4 2 # Data tones 96 48 24 12 MCS0 (kb/s) (BPSK rate 1/2 with 4x frequency repetition) 100 50 — MCS1 (kb/s) (BPSK rate 1/2 with 2x frequency repetition) MCS2 (kb/s) (QPSK rate 1/2 and 2x frequency repetition) MCS3 (kb/s) (QPSK rate 1/2) MCS4 (kb/s) (QPSK rate 3/4) 600 300 150 MCS5 (kb/s) (16-QAM rate 1/2) 1600 MCS6 (kb/s) (16-QAM rate 3/4) 2400 —

Example: Obvious extensions Multiple OFDM implementations commercially available Existing implementations support MCS5 and MCS6 for all options already Using modulation, coding, channelization already defined.

What next? We ask the Working Group to consider minor extension of the OFDM as suggested in our examples.