334r1

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Project IEEE P802.15 Working Group for Wireless
Personal Area Networks (WPANs) Submission Title
Direct Sequence UWB Impulse Radio System Date
Submitted September 13th, 2004 Source
(1)Akira Maeki, Masaru Kokubo, Masayuki
Miyazaki, Kenichi Mizugaki, Ryosuke Fujiwara,
(2)Yasuyuki Okuma, Miki Hayakawa,
Shinsuke Kobayashi, Noboru Koshizuka, Ken
Sakamura Company (1) Hitachi, Ltd., Central
Research Laboratory and Advanced Research
Laboratory, (2) YRP
Ubiquitous Networking Laboratory Address (1)
1-280 Higashi Koigakubo Kokubunji-shi, Tokyo
185-8601 JAPAN (2)28th KOWA
Bldg., 2-20-1, Nishi-Gotanda Shinagawa-ku, Tokyo
141-0031 JAPAN Voice81 42.323.1111, FAX
81 42.327.7849, E-Maila-maeki_at_crl.hitachi.co.
jp Re Response to Call for Proposals Abstrac
t This document proposes Hitachi, Ltd.s PHY
proposal for the IEEE 802.15.4 alternate PHY
standard Purpose Preliminary Proposal for the
IEEE802.15.4a standard. 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.
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Hitachi, Ltd. Preliminary Proposal for IEEE
802.15.4a Alternate PHY
DS- UWB Impulse Radio

• Akira Maeki
• Hitachi, Ltd.

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Contents

• DS-UWB IR Proposal
• Location Awareness
• Summary

4
Direct Sequence UWB Impulse Radio System (DS-UWB
IR)
Impulse Radio
DBPSK
Transmitter
t
PRFTens of MHz
PRF Pulse Repetition Frequency
Receiver
RF
BB
5
UWB Pulse and Spectrum
Initial Target Arbitrary Pulse in Low Band
(3.1-5.1GHz)
-40
-50
-60

• Example
• 2.5ns Gaussian Pulse
• Center Frequency4.1GHz
• 3dB BW660MHz
• TxPower (ave.) - 9.8dBm

EIRP (dBm/MHz)
-70
Low Band (3.1-5.1GHz)
High Band (6-10GHz)
-80
-90
0
1
2
3
4
5
6
7
8
9
10
11
Frequency (GHz)
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Why DS-UWB IR?

• Low Power Consumption
• -Very Simple Architecture
• -Low Rate Sampling ADC Tens of Msps,
  2-4bits
• Low Cost
• -CMOS Implementation is Feasible (Peak Power
  lt10dBm)
• -Low Band (3.1-5.1GHz)
• High Location Accuracy 30cm in 30m range
  (AWGN)
• Best Fit to 4a Applications (Sensor Network etc.)

Low Cost, Low Power, High Location Accuracy!
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Scalability with spread factor
Data Rate Modulation Spread Factor Number of Pulses / Bit
32.0 Mbps DBPSK 1 1
10.7 Mbps DBPSK 3 3
4.57 Mbps DBPSK 7 7
2.13 Mbps DBPSK 15 15
1.03 Mbps DBPSK 31 31
258 kbps DBPSK 124 124
129 kbps DBPSK 248 248
PRF32MHz
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Link Budget
Parameters Value 0.129Mbps 30m Value 1.03Mbps 10m Units
Center Frequency 4096 4096 MHz
Transmit Power (2.5ns Gaussian Pulse) -9.8 -9.8 dBm
PRF 32 32 MHz
Spread Factor 248 31
Data Rate 0.129 1.03 Mbps
Path Loss at 1m 44.7 44.7 dB
Distance 30 10 m
Decay coefficient 2.0 2.0 -
Additional Path Loss at 30m,10m 29.5 20.0 dB
Implementation Loss 3.0 3.0 dB
Antenna gain -3.0 -3.0 dBi
Required Eb/N0 _at_PER1, 32B 14.0 9.8 dB
Noise Power Density -174 -174 dBm
Receiver Total NF 7.0 7.0 dB
Margin 11.9 16.5 dB
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Implementation Feasibility
Example
Transmitter
PA
Data
Spreading
Pulse Generator
Digital PHY
ANT. Switch
Analog RF
MAC
BPF
I
LPF
ADC
Digital Block
LNA
Data

• Matched Filter
• Signal Acquisition
• Tracking
• etc.

0/90
PLL
4.1GHz
Receiver
ADC
LPF
lt150kgate
Q

• Ranging

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Location Awareness

• Trilateration for Location Awareness
• - 3 Known-location Nodes
• - TDOA (Time Difference Of Arrival)
• High Location Accuracy 30cm in 30m range
  (AWGN)

Wireless/Wired Network
Monitor Terminal
Reference Node 2
Server Data Base
Reference Node 3
For Sync.
Node
System Configuration for 2D location
measurements (Synchronization by a node)
Reference Node 1
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Summary
DS-UWB IR is very Simple and Best Fit! -Low
Power -Low Cost CMOS implementation
-High Location Accuracy 30cm in 30m
range at AWGN channel Proposed DS-UWB IR
-fc4.1GHz, BW660MHz at Low Band (3.1-5.1GHz)
-2.5ns Gaussian Pulse with PRF of 32MHz -DBPSK
Modulation