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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: GFSK PHY proposal for Smart Utility Networks Date Submitted: May 10, 2009 Source: Henk de Ruijter, Ping Xiong and P é ter Onódy Silicon Laboratories Inc.
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Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: GFSK PHY proposal for Smart Utility Networks Date Submitted: May 10, 2009 Source: Henk de Ruijter, Ping Xiong and Péter Onódy Silicon Laboratories Inc. Contact: Henk de Ruijter, Silicon Laboratories Inc. Voice: +1 650 623 9155 , E-Mail: hendricus.deruijter@silabs.com Re: TG4g Call for proposals Abstract: PHY proposal towards TG4g Purpose: PHY proposal for the TG4g PHY amendment 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. Slide 1 Henk de Ruijter
Overview Main PHY parameters Why GFSK? USA specifics EU specifics Japan specifics China specifics Frequency tolerance Slide 2 Henk de Ruijter
Main PHY parameters • Modulation type: GFSK • Modulation index: 0.75 • BT factor: 0.5 • Data rate: 40 and 100 kbps depending on local regulations (single data rate per region) • Data whitening: PN9 according to 802.15.4d • 64 bit preamble supporting Antenna Diversity • 16 and 32 bit CRC depending on payload length Slide 3 Henk de Ruijter
Why GFSK? Lower adjacent channel emission than FSK complying to local regulations No linear amplifier needed as appose to BPSK/OQPSK Low complexity in the modem serving low cost endpoints. Proven technology for FHSS regulations Proven technology for Meter reading Slide 4 Henk de Ruijter
Data whitening and Modulation • Same as 15.4d[5] : Slide 5 Henk de Ruijter
Data whitening same as 15.4d[5] • Seed = “111111111” • For details see [5] Slide 6 Henk de Ruijter
PHY Packet Preamble 64 bit SFD 16 bit PHR 8/16 bit PSDU max: 32767 octets • 64 bit preamble to support Antenna Diversity = 16 x Ah • 16 bit SFD to reduce false synchronization = 2DD4h • PHR = 8 or 16 bit to support long payloads • LSB of PHR controls PHR length: “0” = 8bit length, “1” = 16bit length • CRC = 32 bits to support long payloads • LSB of PHR controls CRC type: “0” = CRC16, “1” = CRC32 • When channel hoping is used: one PHY Packet per hop (slow channel hopping. Slide 7 Henk de Ruijter
CRC • CRC depends on PSDU length • Derived from Frame Length field (PHR) • 16 bits CRC up to 127 Octets (802.15.4) • 32 bits CRC for more than 127 Octets (max: 32767 Octets) • Supporting long packets • CRC16 (ITU-T) = 802.15.4b • CRC32 (IEEE 802.3-2005 section1) polynomial: • x32+x26+x23+x22+x16+x12+x11+x10+x8+x7+x5+x4+x2+x+1 • Seed: FFFFFFFF Slide 8 Henk de Ruijter
PSD at 100kbps BW20dB = 112 kHz Slide 9 Henk de Ruijter
PSD at 40kbps BW20dB = 44.8 kHz Slide 10 Henk de Ruijter
Per Region: Slide 11 Henk de Ruijter
Adjacent Channel Power Slide 12 Henk de Ruijter
FCC part 15.247[4] • For frequency hopping systems operating in the 902-928 MHz band: if the 20 dB bandwidth of the hopping channel is less than 250 kHz, the system shall use at least 50 hopping frequencies and the average time of occupancy on any frequency shall not be greater than 0.4 seconds within a 20 second period; • Max peak conducted output power for frequency hopping systems operating in the 902-928 MHz band is 1 Watt for systems employing at least 50 hopping channels. Slide 13 Henk de Ruijter
EU 868MHz Band (non-specific SRD)[1,2] Slide 14 Henk de Ruijter
Constrains FHSS in “g” Band • Sub-bands for alarms are excluded: • Max channel spacing = 100kHz • Minimum number of channels = 47 • Maximum emission at sub-band edges is -36dBm in 100kHz • Max duty cycle = 0.1% • NOTE: The duty cycle applies to the entire transmission (not at each hopping channel). • Max dwell time per channel = 400 ms • The maximum return time to a hopping channel shall be equal or less than the product of 4 x dwell and the number of hopping channels and must not exceed 20 s. • Each channel of the hopping sequence shall be occupied at least once during a period not exceeding the product of 4 x dwell time and the number of hopping channels. • In case of LBT being used for FHSS, this function shall be used at each hop channel. Slide 15 Henk de Ruijter
Channel plan for EU: Note: Sub-bands for Alarm are excluded (gray frequencies) Slide 16 Henk de Ruijter
China (470-510MHz)[6]: • When TX on time is no more than 5 sec then this band can be used for civilian meter reading. • ERP max = 50mW • Max frequency tolerance 100ppm • Spurious limit: -54dBm in 100kHz @ +/-2.5 CHBW - Needs confirmation Slide 17 Henk de Ruijter
References • [1] ERC/REC 70-03 - Version of February 28, 2009 • [2] ETSI 300 220 - V2.2.1 (2008 04) • [3] ARIB STD T96 - v1.0 June 6, 2008 • [4] FCC Part 15 - July 10, 2008 • [5] IEEE Std 802.15.4d™-2009(April 17, 2009) • [6] Chinese technical requirements for low power (short distance) radio equipment (July 26, 2007) Slide 18 Henk de Ruijter