Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Chaotic Pulse Based Communication System Proposal] Date Submitted: [4 January, 2005] Source: [Hyung Soo Lee (1), Cheol Hyo Lee (1), Dong Jo Park (2), Dan Keun Sung (2), Sung Yoon Jung (2), Chang Yong Jung (2), Joon Yong Lee (3)] Company [(1) Electronics and Telecommunications Research Institute (ETRI) (2) Korea Advanced Institute of Science and Technologies (KAIST) (3) Handong Global University (HGU)] Address [(1) 161 Gajeong-dong, Yuseong-gu, Daejeon, Republic of Korea (2) 373-1 Guseong-dong, Yuseong-gu, Daejeon, Republic of Korea (3) Heunghae-eup, Buk-gu, Pohang, Republic of Korea] Voice:[(1) +82 42 860 5625, (2) +82 42 869 5438, (3) +82 54 260 1931], FAX: [(2) +82 42 869 8038] E-Mail: [(1) hsulee@etri.re.kr, (2) syjung@kaist.ac.kr, (3) joonlee@handong.edu] Abstract: [The Chaotic Communication System is proposed for the alternative PHY for 802.15.4a] Purpose: [This submission is in response to the committee’s request to submit the proposal enabled by an alternate 802.15 TG4a PHY] 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.

CFP Presentation for IEEE 802.15.4a Alternative PHY Chaotic Pulse Based Communication System Proposal Electronics and Telecommunications Research Institute (ETRI) Korea Advanced Institute of Science and Technologies (KAIST) Handong Global University (HGU) Republic of Korea

Contents Band Plan Chaotic Pulse PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOPs) Link Budget & Sensitivity Ranging

Band Plan Bandwidth : Two bands - Low band (3.1 to 4.9 GHz) : Mandatory band - High band (5.825 to 10.6 GHz) : for future use Low band 3 4 5 6 7 8 9 10 11 High band 3 4 5 6 7 8 9 10 11

Chaotic Pulse Large base signal [base=2*bandwidth*duration] Flexible bandwidth and signal duration Low cost implementation

Modulation Scheme Multi-coded Pulse Position Modulation (MC- PPM) It is power efficient scheme It has inherent coding gain due to orthogonal multi- codes It can support wide pulse spacing in same data rate condition Less multipath interference between pulses Good for non-coherent energy detection No dynamic threshold problem Disadvantage in On-Off Keying (OOK) based on non-coherent energy detection

Multi-Coded PPM (MC-PPM) Operation example (L=3, Ns=4) * Ref : 15-04-0485-04-004a-multi-coded-bi-orthogonal-ppm-mc-bppm-based-impulse-radio-technology Data block ( L bits ) Ex. L=3 Orthogonal code set ( Code Length : Ns ) Ex. Ns=4 Multi-coded symbol ( Code rate : L/Ns ) Ex. Code rate = 3/4 1 -1 -3 Modulation MC-PPM Signal : 1 -3 1 1

Data Frame Structure Frame structure of PPDU 1 data block (L data) interval of PSDU : : # of Repetitions : Orthogonal Code length : Position number for MC-PPM ... Preamble SFD PHR PSDU 4 1 1 32 : # of bits per data block : Orthogonal code length : # of repetitions : Pulse bin width (duration) : Total transmit time duration of a data block : Guard time for processing delay : Multi-coded chip duration : Multi-coded symbol duration

Transceiver Architecture Transmitter Receiver Data Modulator MC-PPM Channel Data Encoder Orthogonal Multi-code Data Pulse Generator Data Decoder Orthogonal Multi-code Data DeModulator MC-PPM Energy Detector Location

PHY-SAP Data Rates Flexible data rates can be supported according to several design parameter (Tm, L, Ns, Nr, Tg) Tp Tm L Ns Nr Tg Data Rate 20ns 200ns 1 16 128 0ns 1.190 kbps 3 228 kbps 8 457 kbps 2.44 Mbps

Data Throughput ∙∙∙∙ Transmission time (ttx) & Data throughput (Rth) LIFS tACK tlong_frame tACK_frame ∙∙∙∙ ttx Transmission time (ttx) & Data throughput (Rth) For L=3, Ns=8, Nr=1,Tg=0ns (457kbps) ttx = tlong_frame + tACK + tACK_frame + LIFS = 614.4 u + 25.6 u + 187.7 u + 85.3 u = 913 u Rth = 32×8 / 913u ≈ 280.3 kbps ( Nominal throughput based on 32 bytes payload ) For L=3, Ns=16, Nr=1,Tg=0ns (228kbps) = 1228.8 u + 51.2 u + 375.5 u + 170.7 u = 1826.2 u Rth = 32×8 / 1826.2 u ≈ 140.2 kbps

Comments on 1kbps PHY-SAP Data Rate Burst Transmission Scheme << Example >> L=3, Ns=8, Nr=1,Tg=0ns (457kbps) L=3, Ns=16, Nr=1,Tg=0ns (228kbps) 32*8/3 Data Blocks 1 Packet Time Duration

Signal Acquisition Energy detection based acquisition Acquisition should be performed in order to make synchronization and demodulate data Procedure If the output of energy detector exceeds the threshold level, we think that the signal is acquired. Threshold level for acquisition Determined relative to estimated noise level

Synchronization Non-coherent Synchronization Procedure Assume Nint square-law integrator Divide Tm time into total Nint time slots (each time slot contains Tm / Nint time) preamble preamble t_s : sync. starting point t_sync : exact sync. point

Synchronization Non-coherent Synchronization Procedure The output value of n-th square-law integrator Estimated synchronization point

MC-PPM Performance : AWGN BER & PER L=3, Ns=8,Nr=1 (457kbps PHY-SAP data rate)

MC-PPM Performance : 4a Channel Models BER & PER L=3, Ns=8,Nr=1

Acquisition & Synchronization Parameters System Parameters Chaotic Pulse [BW=1.8GHz(3.1G-4.9GHz), Tp=20ns] Preamble Length 4 bytes (32 preamble symbols) Tm=200ns, Ts=100ns (5 chaotic pulses of duration 20ns) Preamble Time Duration = 32 symbols*200ns=6.4us Num. of Integrator (Nint) = 10 Assume that only 5 Integrator are implemented in HW Actual Preamble Length = 32 Symbols/(Nint/5)=16 Symbols Sync. Resolution Range = [-10ns, 10ns] Threshold level for acquisition Determined relative to the estimated noise level

Acquisition Performance : AWGN Comments Acquisition performance is dependent on threshold level Env. Dist. Miss Detection Probability (%) 10m ≈0% 30m 0.1%

Synchronization Performance Comments Signal acquisition is assumed Performance depends on Sync. Resolution Range Env. Dist. AWGN Industrial NLOS (CM8) Residential LOS (CM1) Outdoor LOS (CM5) 10m 99% 74% 30m 72% 73%

SOPs Time Division Operating bandwidth Configuration of SOPs 3.1-4.9 GHz can be fully used (Chaotic pulse) Configuration of SOPs Self configuration of SOPs is possible Piconet #1 Active Inactive Piconet #2 Piconet #3

Self Configuration of SOP Passive Scan Repeat scaning one channel (3.1-4.9 GHz) Usage Starting a new piconet (FFD) Association (FFD or RFD)

Link Budget & Sensitivity Parameter (mandatory) Value at d=30m Value at d=10m peak payload bit rate (457kb/s) [ L=3,Ns=8,Nr=1] Average Tx power -8.75 (dBm) Tx antenna gain 0 (dBi) geometric center frequency of waveform 3.90 (GHz) Path loss at 1 meter 44.5dB Path loss at d m 29.54 dB at d =30m 20 dB at d =10m Rx antenna gain Rx power -82.55 (dBm) -73.01 (dBm) Average noise power per bit -117.4 (dBm) Rx Noise Figure 7 (dB) -110.4(dBm) Minimum Eb/N0 (S) [Ep/N0] 20 (dB) Implementation Loss (I) 5 (dB) Link Margin 2.85(dB) 12.39(dB) Proposed Min. Rx Sensitivity Level -85.4(dBm)

Ranging Scheme TOA/TWR (Two Way Ranging) Measurement of Tround_trip Packet 1 Node 1 Node 2 t1 t0 t2 t3 Tprocessing time Tpropagation2 Packet 2 Tpropagation1 Tround trip

Ranging Algorithm Procedure (Algorithm) Potential lock point (peak) length of search region signal leading edge threshold level envelope detector output search for the 1st level-crossing point time (ns) Search for the 1st level-crossing point at the threshold level in negative direction from the initial lock point References: Joon-Yong Lee and Robert A. Scholtz, "Ranging in a dense multipath environment using an UWB radio link" , IEEE Journal on Selected Areas in Communications, vol.20, no.9, pp.1677 - 1683, Dec. 2002 Robert A. Scholtz and Joon-Yong Lee, "Problems in modeling UWB channels", 36'th Asilomar Conference on Signals, Systems & Computers, Nov. 2002

Ranging Performance Performance 802.15.4a channel (cm4) Single user No narrowband interference Pulse width = 2ns Considering one 2ns pulse integrator Pulse repetition period = 200ns Length of search region = 40ns Threshold level was determined relative to noise floor