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doc.: IEEE 802.15-<199r2>
Submission
Slide 1 Anand Dabak, Texas Instruments
November 2000
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: TI PHY Submission to TG3Date Submitted: November 6, 2000Source: Anand Dabak Company Texas InstrumentsAddress 12500 TI Blvd, MS 8632, Dallas, TX 75243, USAVoice:214.480.4389, FAX: 972.761.6967, E-Mail:[email protected]
Re: original document.
Abstract: Submission to Task Group 3 for consideration as the High Rate PHY for 802.15.3
Purpose: Evaluation of Proposal.
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.
November 2000
Anand Dabak, Texas InstrumentsSlide 2
doc.: IEEE 802.15-<199r2>
Submission
Physical Layer Submission to Task Group 3
Anand Dabak
Texas Instruments
November 2000
Anand Dabak, Texas InstrumentsSlide 3
doc.: IEEE 802.15-<199r2>
Submission
High Speed WPAN• Criteria document specifies the following data rates :
– Audio: 128, 448, 896, 1280, 1450, 1536 kbps
– Video: 2.5, 7.3, 9.8, 18 Mbps
– Computer graphics: 15, 38 Mbps
• Propose a 2.4 GHz ISM band high speed WPAN consisting of three modes
– Mode 1: Bluetooth 1.0
– Mode 2: Maximum data rate up to 3.9 Mbps
– Mode 3: Maximum data rate up to 44 Mbps
November 2000
Anand Dabak, Texas InstrumentsSlide 4
doc.: IEEE 802.15-<199r2>
Submission
Salient Features
• Interoperability with Bluetooth
• High throughput: Up to 41 Mbps throughput
• Coexistence with Bluetooth and 802.11b.
• Resistance to microwave, Bluetooth, 802.11b jamming
• Low cost: cost < 1.5 x Bluetooth
• Low sensitivity level: -86 dBm
• Low power consumption
• Designed for FCC compliance
• Compatibility with Bluetooth MAC
• Low risk approach
• 99 percentile coverage in a 10 m radius, same as Bluetooth 1.0
November 2000
Anand Dabak, Texas InstrumentsSlide 5
doc.: IEEE 802.15-<199r2>
Submission
Mode 3 System SpecificationsParameters 1 2 3 4 5
Filter spectrum 802.11b 802.11b 802.11b 802.11b 802.11b
Modulation QPSK QPSK 16 QAM 16 QAM 16 QAM
Scrambling codelength
256 (DSSS) 256 (DSSS) 256 (DSSS) 256 (DSSS) 256 (DSSS)
Symbol rate 11 Msps 11 Msps 11 Msps 11 Msps 11 Msps
Coding Rate ½,Turbo
None Rate ½,Turbo
Rate ¾,Turbo
None
ARQ Optional Optional Optional Optional Optional
Data rate 11 Mbps 22 Mbps 22 Mbps 33 Mbps 44 Mbps
Transmit power -4 dBm 8 dBm 1 dBm 5 dBm 6 dBm
Distance 10 m 10 m 10 m 10 m 5 m
Bit error rate 1e-8 1e-8 1e-8 1e-8 1e-8
Packet error rate 1e-4 1e-4 1e-4 1e-4 1e-4
Receiversensitivity
-91 dBm -79 dBm -86 dBm -82 dBm -72 dBm
Fading margin 17 dB 17 dB 17 dB 17 dB 17 dB
Noise figure 10 dB 10 dB 10 dB 10 dB 10 dB
November 2000
Anand Dabak, Texas InstrumentsSlide 6
doc.: IEEE 802.15-<199r2>
Submission
Link Margin
802.15.1 802.15.3Transmit power
0dBm 1 dBm
Propagation loss (10 m)
70 dB 70 dB
Received power (10 m)
-70 dBm -69 dBm
Fading margin 17 dB 17 dBRequired signal power
-87 dBm -86 dBm
Noise figure 10 dB 10 dBRequired C/N 17 dB 8 dBNoise floor - 114 dBm - 104 dBm
November 2000
Anand Dabak, Texas InstrumentsSlide 7
doc.: IEEE 802.15-<199r2>
Submission
Fading Margin
Points where required frame error rate is not met
10 m
November 2000
Anand Dabak, Texas InstrumentsSlide 8
doc.: IEEE 802.15-<199r2>
Submission
Fading Margin
• Fading margin of 17 dB offers 99 % coverage in 10 m radius
Fading margin (dB) Outage probability0 30 %10 4 %14 1.6 %17 0.8 %20 0.4 %
-70 dBm-80 dBm -60 dBm-90 dBm -50 dBmPower received
Pro
babi
lity
November 2000
Anand Dabak, Texas InstrumentsSlide 9
doc.: IEEE 802.15-<199r2>
Submission
Slot Format
Syncfield
ARQfield
Packet
50 s 50 s
Preamble Header ARQinformation CRC Frame 1 Frame 2 ... Frame N
November 2000
Anand Dabak, Texas InstrumentsSlide 10
doc.: IEEE 802.15-<199r2>
Submission
ARQ Format
• ARQ is performed on all of the frames inside the payload. Each bit in the ARQ payload corresponds to the corresponding frame.
25 sec turn around time
Sync. field Payload (up to 128 bits) CRC 25 sec turn around time
100 s ARQ Frame Length
November 2000
Anand Dabak, Texas InstrumentsSlide 11
doc.: IEEE 802.15-<199r2>
Submission
TDD Scheme
• Slave responds with ARQ packet only in case of a unidirectional link
•Master does not send an ARQ packet in case of a unidirectional link
Master -> Slave Slave -> Master
Sync.field
Payload …
100 s
ARQ
Turn-around
25 s50 s 50 s
Sync.field
Payload …
100 s
ARQ
Turn-around
50 s 50 s 25 s
November 2000
Anand Dabak, Texas InstrumentsSlide 12
doc.: IEEE 802.15-<199r2>
Submission
Throughput
• Assume we use 16 QAM with rate 1/2 coding• Assume we have 100 segments in each packet• Therefore each packet takes 200+100*100=10.2 ms• Each segment has a payload of 2088 bits• Assume we perform PLS every 50 of these packets
• Therefore throughput is 2088*50*100/(10.2*50+7.5) = 20.17 Mbps
• A similar calculation shows that we meet the high end throughput of 40 Mbps using uncoded 16 QAM.Throughput = 4240*50*100/(10.2*50+7.5) = 40.97 Mbps
November 2000
Anand Dabak, Texas InstrumentsSlide 13
doc.: IEEE 802.15-<199r2>
Submission
Mode 3• Begin transmission in mode 1 and identify good 22 MHz bands. • Negotiate to enter mode 3.
• After spending a time T2 in mode 3 come back to mode 1 for time T1.
• Identify good 22 MHz bands.• Again negotiate to enter mode 3, this time possibly on a different 22
MHz band.• Regulatory issues similar to 802.11
• Time allocation T1 and T2 negotiated between the Master and Slave in the beginning depending upon data rate requirements of the Slave.
• Master maintains synchronization of all other Mode 1 devices in the piconet
• Sniff, Beacon, Paging, for other mode 1 devices.
November 2000
Anand Dabak, Texas InstrumentsSlide 14
doc.: IEEE 802.15-<199r2>
Submission
Mode 3 (Example)
Master
Slave 1 Slave 2
Slave 3
Mode 1 Mode 3
Mode 1
Mode 1 Mode 3 Mode 1 Mode 3 Mode 1 Mode 3
November 2000
Anand Dabak, Texas InstrumentsSlide 15
doc.: IEEE 802.15-<199r2>
Submission
Exponential 802.15.3 Channelmagnitude
time10Ts9Ts8Ts7Ts6Ts5Ts4Ts3Ts2TsTs0
RMSs
RMSs
TT
TkTk
kki
e
e
jNNh
/20
/20
2
2212
21
1
),0(),0(
TRMS = 10, 25 ns
November 2000
Anand Dabak, Texas InstrumentsSlide 16
doc.: IEEE 802.15-<199r2>
Submission
Probe, Listen and Select (PLS)
• Intelligently avoids microwave ovens, 802.11b, etc.
• Frequency diversity
Microwave802.11(b) interference
2402 MHz 2480 MHz
PLS selects this bandfor mode 3
November 2000
Anand Dabak, Texas InstrumentsSlide 17
doc.: IEEE 802.15-<199r2>
Submission
Turbo Codes• Serial concatenated convolutional code (SCCC):
– No error floor
– Choose low complexity code. Complexity less than 802.11 (b) convolutional code. Offers better performance compared to 802.11 (b) convolutional code.
– Implemented and tested the Turbo codes.
– 4 state outer and 2 state inner code
D D D
November 2000
Anand Dabak, Texas InstrumentsSlide 18
doc.: IEEE 802.15-<199r2>
Submission
Simulations (AWGN)
November 2000
Anand Dabak, Texas InstrumentsSlide 19
doc.: IEEE 802.15-<199r2>
Submission
Delay Spread Tolerance
• A MMSE-DFE is employed to combat multipath spread– 6 taps ( half-symbol spaced ) feedforward and up to 3 taps
feedback filters are used
– Taps are calculated from channel estimate performed during sync word
– Taps can be adapted using LMS • Combats interference
Feedforward Filter -
Feedback Filter
Output from square root raised cosine filter
To turbo decoder
November 2000
Anand Dabak, Texas InstrumentsSlide 20
doc.: IEEE 802.15-<199r2>
Submission
Delay Spread Results
November 2000
Anand Dabak, Texas InstrumentsSlide 21
doc.: IEEE 802.15-<199r2>
Submission
Dual Mode Radio, RF Cost Estimation• 802.15.1 and 802.15.3 share
– Antenna
– Antenna filter
– Tx/Rx Switch
– LNA
– Transmit modulator
– Power amplifier
• Additional blocks needed– RF/baseband conversion mixers for 802.15.3
– Low pass filters
– AGC amplifier (+/- 20 dB)
• The total RF chip area is less than 20 mm2 in RFBiCMOS
November 2000
Anand Dabak, Texas InstrumentsSlide 22
doc.: IEEE 802.15-<199r2>
Submission
Digital Technology • Digital technology allows integration and hence cost,
power reduction– Adding new features onto an existing chip leads to a small
increase in cost.
Baseband
Silicon area increase
Cost increase
November 2000
Anand Dabak, Texas InstrumentsSlide 23
doc.: IEEE 802.15-<199r2>
Submission
Baseband Blocks
• Baseband blocks– 2, 8 bit A/D’s at 22 MHz each.
– 2, 6 bits D/A’s at a speed of 44 MHz.
– A 16 tap half symbol spaced square root raised cosine filter.
– A 6 tap half symbol spaced feed forward and up to 3 tap symbol spaced feed back equalizer.
– The Turbo decoder size is a total of 50 K gates and 13 Kbytes of RAM.
November 2000
Anand Dabak, Texas InstrumentsSlide 24
doc.: IEEE 802.15-<199r2>
Submission
Baseband (Continued)
• Gate count and silicon area in 0.13 technology.
• 0.13 technology– Highly integrated solution takes advantage of Moore’s Law that
the cost of digital solutions decreases by a factor of 2 every 18 months. Moore’s Law does not apply to analog solutions, which decrease in cost much more slowly.
Baseband block Gate count Chip area (0.13 )A/D size N/A 1.2 mm2
D/A size N/A 0.32 mm2
Digital filter 22.4K 0.14 mm2
Equalizer 14K 0.09 mm2
Turbo Decoder 50K 0.32 mm2
Decoder RAM 13Kbytes 0.23 mm2
MAC 150K 0.94 mm2
November 2000
Anand Dabak, Texas InstrumentsSlide 25
doc.: IEEE 802.15-<199r2>
Submission
Power Consumption (Receive)
Function Power consumption forreceive (mW)
RF (receive) 65 mWA/D 10 mW
Digital filters 5 mWEqualizer 2 mW
Turbo decoder 16 mWTotal PHY power consumption 98 mW
MAC power consumption(estimated)
50 mW
Total PHY + MAC powerconsumption
148 mW
November 2000
Anand Dabak, Texas InstrumentsSlide 26
doc.: IEEE 802.15-<199r2>
Submission
Power Consumption (Transmit)
Function Power consumption fortransmit (mW)
PA 25 mWRF transmit (excluding PA) 65 mW
D/A 6 mWDigital filters 4 mW
Total PHY power consumption 100 mWMAC power consumption
(estimated)50 mW
Total PHY + MAC powerconsumption
150 mW
November 2000
Anand Dabak, Texas InstrumentsSlide 27
doc.: IEEE 802.15-<199r2>
Submission
Cost Comparison
• Estimated cost increase for (802.15.3 + 802.15.1) solution over 802.15.1 only solution:– RF cost increase is 25 %
– Baseband cost increase is 60 %
• Overall cost of (802.15.3 + 802.15.1) < 1.5Xcost of 802.15.1.
November 2000
Anand Dabak, Texas InstrumentsSlide 28
doc.: IEEE 802.15-<199r2>
Submission
Time to Market
• Shares most blocks with other wireless systems– Reuse 802.15.1 and 802.11(b) RF solutions
– Turbo decoder employed in 3G WCDMA systems
– Equalizer similar in design to 802.11(b), but simpler due to much smaller delay spreads.
– Other blocks including A/D converters, D/A converters are readily available.
• Hence can leverage off of other closely related existing wireless systems.
• Hence short time to market.
November 2000
Anand Dabak, Texas InstrumentsSlide 29
doc.: IEEE 802.15-<199r2>
Submission
Conclusions
• Our solution – Satisfies minimum throughput of 20 Mbps
– Can go up to 40 Mbps for high bandwidth applications
– Maintains same link margin as Bluetooth 1.0 hence has 99 % coverage in a 10 m radius
• Same indoor operation range for Bluetooth 1.0 and 802.15.3.
• User will not have communication signal fade in and out.
– Allows high level of integration allowing cost to fall exponentially following Moore’s Law.
– Low cost solution (< 1.5 X Bluetooth 1.0)
– Low power consumption of less than 150 mW on transmit and receive
– Rapid time to market by leveraging off of existing wireless systems
November 2000
Anand Dabak, Texas InstrumentsSlide 30
doc.: IEEE 802.15-<199r2>
Submission
General Solution Criteria Comparison Values
CRITERIA Comparison Values- Same +
Unit ManufacturingCost ($)
> 2 x equivalent Bluetooth 1 1.5-2 x equivalent Bluetooth1
< 1.5 x equivalent Bluetooth1
Interference andSusceptibility
Out of the proposed band:Worse performance thansame criteria
In band: -: Interferenceprotection is less than 25 dB
Out of the proposed band:based on Bluetooth 1.0b
In band: Interferenceprotection is less than 30 dB
Out of the proposed band:Better performance thansame criteria
In band: Interferenceprotection is greater than 35dB
IntermodulationResistance
< -45 dBm -35 dBm to - 45 dBm > -35 dBm
Jamming Resistance Any 3 sources jam Any 2 sources jam. No more than 1 sourceMultiple Access No Scenarios work Handles Scenario 2 One or more of the other 2
scenarios workCoexistence Individual Sources: 0%
Total: < 3Individual Sources: 50%Total: 3
Individual Sources: 100%Total: > 3 (Total=7)
Interoperability False True N/AManufactureability Expert opinion, models Experiments Pre-existence examples,
demoTime to Market Available after 1Q2002 Available in 1Q2002 Available earlier than
1Q2002Regulatory Impact False True N/AMaturity of Solution Expert opinion, models Experiments Pre-existence examples,
demo
Scalability Scalability in 1 or less than ofthe 5 areas listed
Scalability in 2 areas of the 5listed
Scalability in 3 or more ofthe 5 areas listed
November 2000
Anand Dabak, Texas InstrumentsSlide 31
doc.: IEEE 802.15-<199r2>
Submission
PHY Criteria Comparison Values
CRITERIA Comparison Values- Same +
Size and FormFactor
Larger Compact Flash Type 1card
Smaller
MinimumMAC/PHYThroughput
< 20 Mbps (without MACoverhead)
20 Mbps + MACoverhead
> 20 Mbps + MACoverhead
High EndMAC/PHY
Throughput (Mbps)
N/A 40 Mbps + MACoverhead
40 Mbps + MACoverhead
Frequency Band N/A (not supported byPAR)
Unlicensed N/A (not supported byPAR)
Number ofSimultaneouslyOperating Full-
Throughput PANs
< 4 4 >4
Signal AcquisitionMethod
N/A N/A N/A
Range < 10 meters > 10 meters N/ASensitivity N/A N/A N/A
Delay SpreadTolerance
< 25 ns > 25 ns
PowerConsumption
> 1.5 watts Between .5 watt and 1.5watts
< .5 watt