Joint DSSS Proposal for 802.15.4g Merged proposal : 09-471, 09-283, 09-307 1Michael Schmidt, 2Y X Fu, 2J Shen, 2X Wang, 2Haituo Liu, 2L Li, 2Z Zhao, 2Z.F Zhao, 3Ted Myers, 3David Howard 1Atmel, 2Huawei/SIMIT/VINNO, 3On-Ramp Wireless

Bands included No bandwidth limitation in bands 780MHz (China) 868MHz (EU) 863 – 870 MHz 915MHz (US) 902 – 928 MHz 2450MHz (Intl) 2400 – 2483.5 MHz

DSSS benefits Better sensitivity increases range for hard to reach meters and challenging environments, especially in-building Good complement to Merge FSK Proposal Trade-off between processing gain and data rate with fixed bandwidth – long range for reduced data rate and short range for high data rate Different data rates can be obtained by simply changing the spreading gain, with same RF design

Merged proposal Atmel/Huawei/OnRamp/SIMIT/VINNO Summary parameters   Merged proposal Atmel/Huawei/OnRamp/SIMIT/VINNO Frequency 863-870MHz 779-787MHz 900MHz/ 2.4GHz PSDU Format 8 octets SFD SFD: 8 bits PHR Date rate: 2 bits Frame Length: 11 bits Reserved: 2bits Parity Check: 1bit PSDU: 4-2047 octets SFD Content 0xE5 Spreading factor 1/2/4/8 8/16/32/128 PSDU Date Rate(kbps) 200/100/50/25 500/250/125/62.5 125/62.5/31.2/7.8 Modulation OQPSK/precoded GMSK (p/2 BPSK) Channel Code 1/2 rate Convolutional code Shape Raised Cosine (OQPSK)/ Gaussian Pulse (GMSK) Chip rate 200kchip/s 500kchip/s 1Mchip/s Channel Spacing 400kHz 1MHz 200/400kHz Sprading Factor (Code) 128 (128,1) 64 32 (32,1) 16 (16,1) 8 (32,4) (32,4) 15.4 (8,1)? 4 (16,4) 2 (8,4) 1 (4,4) CRC CRC-32

Modulation O-QPSK GMSK Raised cosine shape r=0.8 Pre-coded Equivalent to p/2 – BPSK (*) (*) for example see: Draft P802.15.3c/DF3, page 45: "a) The standard supports the use of MSK/GMSK modulations with appropriate filtering and pre-coding as an alternative way of generating π/2 BPSK waveform signals for the SC PHY mode."

Channel Code ½ rate convolution code Benefits Interleaver Complexity Supports long frame requirements in PAR Provides larger gain compared to spreading as decrease data rate by ½ Used in IS-95 and other systems Consider interleave to improve resistance to burst interference Interleaver Max depth of 32 information octets Complexity Constraint length k=7

779 – 787 MHz PHY Chip rate = 500kcps Channel center frequency (MHz) 779.5, 780.5, 781.5, 782.5, 783.5, 784.5, 785.5, 786.5 Spreading code (4,4), (8,4), (16,4), (32,4) PSDU Data rate (bps) 500k,250k, 125.5k, 62.5k Preamble spreading (32,1) 7

863 – 870 MHz PHY Chip rate = 200kcps Channel center frequency (MHz) 863.4, 873.8, 864.2, 865, 865.4, 866, 866.6, 867,2, 867.8, 868.3, 868.95 Spreading code (4,4), (8,4), (16,4), (32,4) PSDU data rate (bps) 200k, 100k, 50k, 25k Preamble spreading (32,1) 8

902 – 928 MHz PHY Chip rate = 1Mcps Channelization Spreading code 400kHz channels, like Merged FSK Proposal, but not all used Spreading code (128,1), (32,1), (16,1), (32,4) PSDU data rate 125k, 62.5k, 31.25k, 7.8k Preamble spreading (32,1) 9

2400 – 2483.5 MHz PHY Chip rate = 1Mcps Channelization Spreading code 400kHz channels, like Merged FSK Proposal, but not all used Spreading code (128,1), (32,1), (16,1), (32,4) Data rate (bps) 125k, 62.5k, 31.25k, 7.8k Preamble spreading (32,1) 10

(N,1) - FEC Concatenation 11

(N,4) - FEC Concatenation 12

PPDU Format PHR Field 2 octets Frame Length(11 bits) 4~2047 Bits: 64 8 11 Preamble SFD Data Rate Mode Frame Length Reserved Parity Check PSDU Includes FCS PHR Field 2 octets Frame Length(11 bits) Indicate the frame length from 0 – 2047 bytes Compatible with PPDU Format of 802.15.4 -2006 Date Rate Field (2 bits) Indicate the spreading sequence to binary data of PSDU, RX adjust receive PN sequence according to this field Parity Check Field (1 bit) Check the PHR field