IEEE802.15.4a: Ultra Low Power Transceiver for Wireless ...
Transcript of IEEE802.15.4a: Ultra Low Power Transceiver for Wireless ...
IEEE802.15.4a: Ultra Low Power Transceiver for
Wireless Sensors Enabling Precision Location
Mr Ciaran Connell (CEO) & Mr Michael McLaughlin (President & CTO)
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DecaWave
Wireless Factory Workshop
15 -16 December 2008 – ETSI, Sophia Antipolis, France
“The Internet of Things”A World where anybody or anything can locate and communicate with any other body or thing, made possible by pervasive, extremely low power, low cost, high data rate wireless transceivers.
Our Vision
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UWB for Precision Locating
Time
Direct path through partition
(Time of flight for this 1st path gives distance)
Reflection off ceiling
Reflection off wall then ceiling
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Reflection off wall
(Receive Signal Strength is dominated by this path which has been attenuated by long flight path)
ceiling
Resolving Multipath Components, given that• Resolution α 1/BW• d = c.tthus• 802.15.11: 20MHz 1/BW = 0.05µs = 15m =>=>=>=> low resolution• 802.15.4a: 1300MHz 1/BW = 0.8ns = 24cm =>=>=>=> very high resolution
Wireless Personal Area NetworkIEEE802.15.1
(Bluetooth)RFID IEEE802.15.4
(ZigBee)IEEE802.15.3a IEEE802.15.4a IEEE802.15.3c IEEE802.15.6
Utility Cordless Identification ControlFile Transfer
(Wireless USB)Location plus
ControlVideo Link
(Wireless MM)Body Area Networks
Freq Range 2.40-2.48 GHz1 band in kHz
8 bands in MHz3 bands in GHz
868 MHz902-928 MHz2.40-2.48 GHz
3-10 GHz (USA)6-8.5 GHz (Europe)
7-9 GHz (Japan)
3-10 GHz (USA)6-8.5 GHz (Europe)
3 bands in 60GHz Band
(2 bands similar US & Japan, 1 different)
ModulationGFSK, π/4 DQPSK,
8PSKFSK, ASK, PSK,
BPSK,FM, AM
BPSK(868/915MHz)OQPSK(MSK)
(2.4GHz)
QPSK(MB-OFDM)BPSK/QPSK(DS-UWB)
PPM with BPSK In standards discussion
Multiple Access
FHSS TDMA/FDMA CSMA/CATFI-OFDM
(MB-OFDM)Ternary CDMA
(DS-UWB)
FDM / CDMA / Time Hop
Duplex
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Source: IEEE & DecaWave
Duplex (Uplink/Downlink)
TDD TDD, TDM TDD TDD TDD
Channel Bandwidth
1 MHz Typically200kHz/500kHz 2 MHz
528 MHz(MBOFDM)1.368GHz, 2.736GHz (DS-UWB)
500MHz, 1.3GHz
# Channels 79As required by local
radioregulations
1 (868MHz)10 (915MHz)16 (2.4GHz)
13 (MB-OFDM)
2 (DS-UWB)
30 (USA)16 (Europe)12 (Japan)
Peak Data Rate3Mbps 848 kbps
20 kbps (868MHz)40 kbps (915MHz)250 kbps (2.4GHz)
480 Mbps typical1 Gbps planned
850 kb/s mandatory110kb/s, 6.81Mb/s
& 27.24 Mb/s optional
1.4Gbps, 2.8Gbps4.2Gbps
• "An international standard for an ultra-low complexity, ultra-low cost, ultra-low power consumption alternate PHY for IEEE Std 802.15.4.”
Standards IEEE 802.15.4a
802.15.4aRatified Q1 ‘07
Location,Communication,
Control
27 Mbps, 500m range,
with location & mobility
802.15.4aBaseline: Q1 ’05Completed: Q4 ’06Ratified: Q1 ‘07
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• Decawave’s IP (patents and trade secrets) allows us to have an ultra-low complexity coherent receiver, thereby giving the benefits of superior range at ultra-low power and ultra-low cost
IEEE Standard UtilityCapability
mobilityRatified: Q1 ‘07
ScenSor (Seek, Control, Enable, Network / Sense, Obey, Respond)
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5Price
Location PrecisionIntegration
( € 2 in volume )
( +/- 10 cm )( 7mm2 90nm RFCMOS )
Precision Location: The Future
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0
1
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Range
Tag Density
Standards BasedPower Consumption
Data Rate
Availability
( 25m NLOS, 70m LOS and �500m LOS @ 110kbps )
( > 11,000 tagsIn 20m radius )
( IEEE802.15.4a )
( Prototypes Jan ‘09Silicon Aug ‘09 )
( 6.8Mbps )
( runs off a single watch Battery for 10 years )
TP TG RG TP TG RG
Non Line Of Sight (NLOS) Range
• is the range when operating in the presence of obstructions, such as walls and objects • ScenSor’s performance is better than WiFi• allows RTLS to be deployed in WLAN APs with current density profile of WLAN APs.
ScenSor’s Range
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Line Of Sight (NLOS) Range
• is the range when operating without obstructions, such as walls and objects • ScenSor’s performance is significant• allows RTLS to be deployed in very large factories.
4a Receive Signal Buried In Thermal Noise
4a Receive Signal @ 110kps and noise at -29dB SNR. This corresponds to a distance of 500 meters outdoors, 40 meters indoors
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4a Receive Signal @ 6.8Mbps and noise at -11dB SNR. This corresponds to a distance of 100meters outdoors, 22 meters indoors
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15C
hann
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Bandplan Facilitating WorldWide Deployment
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0 1000 2000 3000 4000 5000 6000 7000 8000 9000 100000
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2
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Frequency, MHz
Japan @ >50MbpsJapan with DAAKoreaKorea with DAA or LDC
USAUSA indoors and outEuropeEurope with DAA or LDC
4a 500MHz4a >1GHz802.11 / Zigbee
DecaWave’s 4a Channel Model
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0.8
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1
p E(E
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20Mhz
500Mhz
25
30
35
40
45
50
Pat
h Lo
ss (dB
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Attenuation of worst 10% ofchannels at 10 meters
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-15 -10 -5 0 5 100
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E (dB)
p E
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102
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10
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20
distance (meters)
Pat
h Lo
ss (dB
s)
UWB Path Loss
Worst 10% of UWB Path LossNarrowband Path Loss
Worst 10% of Narrowband Path Loss
802.15.4a FEC and Symbol Structure
IEEE 802.15.4a was designed to be used by either a coherent or non−coherent receiver
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IEEE 802.15.4a Ranging Options
Two way ranging option
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4a4a
IEEE 802.15.4a also has the option of being transmit only
AP0 AP1
d14
Wireless 4a AP Clock Synchronisation
AP3
d01
d03
AP4
AP2d12
d
d24
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AP3 d34
Central Location Engine
Precise distances between nearby APs are known to the Central Location Engine
Development Plan & Prototype
• Prototypes in-house• 7 customers ordered set of
5 prototypes delivery Jan’09• First Silicon Aug’09• Production Ready Silicon
Q1 ‘10.
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Q1 ‘10.