Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1

• 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 [phone]
• E-Mail (1) hsulee_at_etri.re.kr, (2)
  syjung_at_kaist.ac.kr, (3) joonlee_at_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
  committees 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.

2
CFP Presentation for IEEE 802.15.4aAlternative
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
3
Contents

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

4
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

High band
5
Chaotic Pulse

• Large base signal base2bandwidthduration
• Flexible bandwidth and signal duration
• Low cost implementation

6
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
• Low cost implementation
• No dynamic threshold problem

7
Multi-Coded PPM (MC-PPM)

• Operation example (L3, Ns4)
• Ref 15-04-0485-04-004a-multi-coded-bi-orthogon
  al-ppm-mc-bppm-based-impulse-radio-technology

Modulation
MC-PPM Signal
1
-3
1
1
8
Data Frame Structure

• Frame structure of PPDU
• 1 data block (L data) interval of PSDU

Preamble
SFD
PHR
PSDU
4
1
1
32
9
Transceiver Architecture

• Transmitter
• Receiver

10
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
20ns 200ns 3 16 1 0ns 228 kbps
20ns 200ns 3 8 1 0ns 457 kbps
20ns 200ns 1 1 1 0ns 2.44 Mbps
11
Data Throughput

• Transmission time (ttx) Data throughput (Rth)
• For L3, Ns8, Nr1,Tg0ns
• ttx tlong_frame tACK tACK_frame LIFS
• 614.4 u 25.6 u 187.7 u 85.3 u 913 u
• Rth 328 / 913u 280.3 kbps
• ( Nominal throughput based on 32 bytes payload
  )
• For L3, Ns16, Nr1,Tg0ns
• ttx tlong_frame tACK tACK_frame LIFS
• 1228.8 u 51.2 u 375.5 u 170.7 u
  1826.2 u
• Rth 328 / 1826.2 u 140.2 kbps
• ( Nominal throughput based on 32 bytes payload
  )

12
Comments on 1kbps PHY-SAP Data Rate

• Burst Transmission Scheme
• ltlt Example gtgt
• L3, Ns8, Nr1,Tg0ns
• (457kbps)
• L3, Ns16, Nr1,Tg0ns
• (228kbps)

13
Signal Acquisition

• Energy detection based acquisition
• Acquisition is performed before synchronization
• If the maximum square-integrator output (used for
  synchronization) exceeds the threshold level, we
  think that the signal is acquired.

14
Synchronization

• Non-coherent Synchronization Procedure
• Assume N_int square-law integrator
• Divide T_m time into total N_int time slots
• (each time slot contains T_m/N_int time)

t_s sync. starting point t_sync exact sync.
point
15
Synchronization

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

16
MC-PPM Performance AWGN

• BER PER
• L3, Ns8,Nr1

17
MC-PPM Performance 4a Channel Models

• BER PER
• L3, Ns8,Nr1

18
Acquisition Synchronization Parameters

• System Parameters
• Chaotic Pulse BW1.8GHz(3.1G-4.9GHz), Tp20ns
• Preamble Length
• 4 bytes (32 preamble symbols)
• Tm200ns, Ts100ns (TsNsTp -gt Ns5)
• Preamble Time Duration 32 symbols200ns6.4us
• Num. of Integrator (Nint) 10
• In HW Implementation, Only 5 Integrator are used
• Actual Preamble Length 32 Symbols/(Nint/5)16
  Symbols
• Sync. Resolution Range -10ns, 10ns
• Threshold level for acquisition
• Related to false alarm probability
• Determined relative to noise level

19
Acquisition Performance AWGN

• Comments
• Acquisition performance is dependent on Threshold
  level

Env. Dist. Miss Detection Probability ()
10m 0
30m 0.1
20
Synchronization Performance

• Comments
• Signal acquisition is assumed
• Performance depends on Sync. Resolution Channel

Env. Dist. AWGN Industrial NLOS (CM8) Residential LOS (CM1) Outdoor LOS (CM5)
10m 99 74 74 74
30m 99 72 73 73
21
SOPs

• Time Division
• Operating bandwidth
• 3.1-4.9 GHz can be fully used (Chaotic pulse)
• Configuration of SOPs
• Self configuration of SOPs is possible

22
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)

23
Link Budget Sensitivity
Parameter (mandatory) Value at d30m (mandatory) Value at d10m
peak payload bit rate (457kb/s) L3,Ns8,Nr1 (457kb/s) L3,Ns8,Nr1
Average Tx power -8.75 (dBm) -8.75 (dBm)
Tx antenna gain 0 (dBi) 0 (dBi)
geometric center frequency of waveform 3.90 (GHz) 3.90 (GHz)
Path loss at 1 meter 44.5dB 44.5dB
Path loss at d m 29.54 dB at d 30m 20 dB at d 10m
Rx antenna gain 0 (dBi) 0 (dBi)
Rx power -82.55 (dBm) -73.01 (dBm)
Average noise power per bit -117.4 (dBm) -117.4 (dBm)
Rx Noise Figure 7 (dB) 7 (dB)
Average noise power per bit -110.4(dBm) -110.4(dBm)
Minimum Eb/N0 (S) Ep/N0 20 (dB) 20 (dB)
Implementation Loss (I) 5 (dB) 5 (dB)
Link Margin 2.85(dB) 12.39(dB)
Proposed Min. Rx Sensitivity Level -85.4(dBm) -85.4(dBm)
24
Ranging Scheme

• TOA/TWR (Two Way Ranging)
• Measurement of Tround_trip

25
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

26
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