doc IEEE 802 15 04 0525 00 004

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Project: IEEE P 802. 15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Proposed Code Sequences for IEEE 802. 15. 4 a Alt-PHY] Date Submitted: [13 Sept, 2004] Source: [Francois Chin, Sam Kwok, Xiaoming Peng, Kannan, Yong- Huat Chew, Chin-Choy Chai, Hongyi Fu, Manjeet, Tung-Chong Wong, T. T. Tjhung, Zhongding Lei, Rahim] Company: [Institute for Infocomm Research, Singapore] Address: [21 Heng Mui Keng Terrace, Singapore 119613] Voice: [65 -68745684] FAX: [65 -67768109] E-Mail: [chinfrancois@i 2 r. a-star. edu. sg] Re: [Response to the call for proposal of IEEE 802. 15. 4 b, Doc Number: 15 -04 -0239 -00 -004 b] Abstract: [This presentation compares all proposals for the IEEE 802. 15. 4 b PHY standard. ] Purpose: [Proposal to IEEE 802. 15. 4 b Task Group] Notice: This document has been prepared to assist the IEEE P 802. 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 P 802. 15. Submission 1 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Proposed Code Sequences for IEEE 802. 15. 4 a Alt-PHY Francois Chin Institute for Infocomm Research Singapore Submission 2 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Proposed System Parameters Chip rate 16 Mcps Pulse Rep. Freq. 16 MHz Symbol Rate 0. 5 MHz Min. info. bit / sym. 4 bit / symbol Max bit rate 4 x 0. 5 = 2. 0 Mbps # Chip / symbol (Code length) 32 #Code Sequences/ piconet 16 (4 bit/symbol) Code position modulation (CPM) Lower bit rate 250 kbps (2 -layer CPM) 31. 25 kbps (3 -layer CPM) 3. 90625 kbps (4 -layer CPM) Modulation BPSK or On-Off Keying (OOK) Total # simultaneous piconets supported 6 Multple access for piconets Fixed band sequence for each piconet Submission 3 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Code Sequence Set Seq 1 111000110101000010010110011 Seq 2 1011100010101101000011001001111 Seq 3 110111110100101011000011100 Seq 4 010110001111100110100100001 Seq 5 1111001001100001011010100011101 Seq 6 001110000110101001011111011 • 31 -chip M-Sequence set • Only one sequence and one fixed band (no hopping) will be used by all devices in a piconet • Logical channels for support of multiple piconets • 6 sequences = 6 logical channels (e. g. overlapping piconets) Submission 4 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Gray Coded Code Position Modulation (CPM) Symbol Cyclic shift to right by n chips, n= 32 -Chip value To obtain 32 -chip per symbol, cyclic shift first, then extend 1 -chip 0000 0 111000110101000010010110011 1 0001 2 111110001101010000100101100 0 0011 4 001111100011010100001001011 0 0010 6 110011111000110101000010010 1 0110 8 101100111110001101010000100 1 0111 10 001011001111100011010100001 0 0101 12 010010110011111000110101000 0 0100 14 000100101100111110001101010 0 1100 16 100001001011001111100011010 1 1101 18 1010000100101100111110001101110 1 1111 20 1010100001001011001111100011011 1 1110 22 1110101000010010110011111000110 1 1010 24 1011101010000100101100111110001 1 1011 26 011010100001001011001111100 0 1001 28 000110101000010010110011111 0 1000 30 000110101000010010110011111 0 Submission 5 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 N-layer CPM • The output of the symbol-to-chip mapper is fed into the same symbol-tochip mapper for N times • With N = 2, 4 bits is mapper to 32/4*32 = 256 chips • With N = 3, 4 bits is mapper to 32/4*32 /4 * 32 = 2048 chips Example of 3 -layer CPM (for 31. 25 kbps) 0001 31. 25 kbps …. 1 1 1 0 0 0 1 1 1 0 1 0 0 1 1 0 0 0 …. 250 kcps 1 0 1 0 0 1 1 0 0 1 1 1 0 0 0 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 …. 2 Mcps 1 0 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 0 0 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 …. 16 Mcps Submission 6 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Synchronisation Preamble Correlator output for synchronisation • Code sequence has excellent autocorrelation properties • Preamble is constructed by repeating base Code Sequence • Unique – no symbol & spreading combination can construct this preamble • Unlike 15. 4, where preamble is constructed by 8 x ‘ 0000’ symbols Submission 7 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Coding Gain of M-Sequence Codes • ~2. 5 d. B @ BER=10 -5 in AWGN Submission 8 Francois Chin, Institute for Infocomm Research (I 2 R)

doc. : IEEE 802. 15 -04 -0525 -00 -004 b Sept 2004 Summary Advantages of M-Sequence Codes • Low auto-correlation • One sequence for the entire piconet for • Synchronisation; • Symbol-to-chip mapping; • Further symbol spreading to achieve reduced rate at longer range Submission 9 Francois Chin, Institute for Infocomm Research (I 2 R)