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Transcript of Doc.: IEEE 802.15-03/139r4 Submission July 2003 Didier Helal and Philippe Rouzet, STMSlide 1...
July 2003
Didier Helal and Philippe Rouzet, STMSlide 1
doc.: IEEE 802.15-03/139r4
Submission
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: [STMicroelectronics proposal for IEEE 802.15.3a Alt PHY]Date Submitted: [14 July, 2003]Source: [Didier Helal (Primary) Philippe Rouzet (Secondary)] Company [STMicroelectronics]Address [STMicroelectronics, 39 Chemin du Champ des Filles 1228 Geneve Plan-les-Ouates, Switzerland]Voice [+41 22 929 58 72 or +41 22 929 58 66 ], Fax [+41 22 929 29 70], E-Mail :[[email protected], philippe [email protected]]
Re:
[This is a response to IEEE P802.15 Alternate PHY Call For Proposals dated 17 January 2003 under number IEEE P802.15-02/372r8 ]
Abstract: [This document contents the proposal submitted by ST for an IEEE P802.15 Alternate PHY based on UWB technique.]
Purpose: [Presentation to be made during July IEEE TG3a session in San Francisco, California]
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.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 2
doc.: IEEE 802.15-03/139r4
Submission
July 2003, San Francisco, California
STMicroelectronics Proposal for
IEEE 802.15.3a Alternate PHY
Didier Hélal, Philippe Rouzet
R. Cattenoz, C. Cattaneo, L. Rouault, N. Rinaldi,
L. Blazevic, C. Devaucelle, L. Smaïni, S. Chaillou
July 2003
Didier Helal and Philippe Rouzet, STMSlide 3
doc.: IEEE 802.15-03/139r4
Submission
Contents
• Introduction to Pulse Position Modulation
• UWB PHY Proposal
• Performances results
July 2003
Didier Helal and Philippe Rouzet, STMSlide 4
doc.: IEEE 802.15-03/139r4
Submission
Pulse Position Modulation (1)
Time
PRP = Pulse Repetition Period = 1/PRF
A system with a PRF of 250MHz transmits 250 million pulses per second
Time
PRF = Pulse Repetition Frequency
A system with a PRF of 250MHz transmits one pulse every 4 nanosecond
July 2003
Didier Helal and Philippe Rouzet, STMSlide 5
doc.: IEEE 802.15-03/139r4
Submission
Pulse Position Modulation (2)
Time
A system with a PRF of 250MHz using a 4-PPM transmits 500 million bits per second
Position 1
Time
A system with a PRF of 250MHz using a 4-PPM + Polarity transmits 750 million bits
per second
Position 2Position 3Position 4
July 2003
Didier Helal and Philippe Rouzet, STMSlide 6
doc.: IEEE 802.15-03/139r4
Submission
1 2
Tp = 300ps
1 bit / pulse
2 bits / pulse
3 bits / pulse
t
3 4Equally spaced Positions
Polarity
2-PPM +
Polarity
4-PPM +
Polarity
July 2003
Didier Helal and Philippe Rouzet, STMSlide 7
doc.: IEEE 802.15-03/139r4
Submission
BIT MAPPING
• Gray-invert mapping: takes advantage from the bi-orthogonal modulation PPM+Polarity.
000 001 011 010
101100110111
PPMerror
antipodalerror PP
July 2003
Didier Helal and Philippe Rouzet, STMSlide 8
doc.: IEEE 802.15-03/139r4
Submission
MODULATION
PAYLOAD Bit Rate Target
PAYLOAD Bit Rate Effective
Modulation Code-rate
PRP
55 Mbps 62.5 Mbps BPSK 1/2 8 ns
110 Mbps 125 Mbps BPSK +
2-PPM
1/2 8 ns
200 Mbps 250 Mbps BPSK +
4-PPM
2/3 8 ns
480 Mbps 500 Mbps BPSK + 4PPM
2/3 4 ns
July 2003
Didier Helal and Philippe Rouzet, STMSlide 9
doc.: IEEE 802.15-03/139r4
Submission
PPM Modulation capacity
• Increasing the number of pulse positions brings better efficiency
-2 0 2 4 6 8 10 120
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Eb/No (dB)
Cap
acity
/Max
imum
ach
eiva
ble
capa
city
2-PPM 4-PPM 8-PPM16-PPM32-PPM
July 2003
Didier Helal and Philippe Rouzet, STMSlide 10
doc.: IEEE 802.15-03/139r4
Submission
Channel coding options (1)
• Convolutional code
– Code rate ½, constraint length K=7, [133,171]:
– Puncture table for code rate = 2/3: [1 1 0 1 1 1 1 0]
z-1InputData
Coded bit 1
Coded bit 2
z-1 z-1 z-1 z-1 z-1
July 2003
Didier Helal and Philippe Rouzet, STMSlide 11
doc.: IEEE 802.15-03/139r4
Submission
Channel coding options (2)
• Turbo codes PCCC (Parallel Concatenation of Convolutional Codes)
– Code rate 1/3. With puncturing:1/2, 2/3,7/8.
– RSC (recursive systematic convolutional) 13,15(octal def.).
– Block size: 512.
– Low latency : 5 s
July 2003
Didier Helal and Philippe Rouzet, STMSlide 12
doc.: IEEE 802.15-03/139r4
Submission
Adaptive band Pulse shape
• Pulse shape should be adapted to any regulation, provided the pulse power spectral density fits emission mask.
• Flexibility on pulse shape enables compatibility with more stringent regulations worldwide.
• See ref. IEEE 802.15-03/211r0.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 13
doc.: IEEE 802.15-03/139r4
Submission
Backward and Forward compatibility
• First generation systems will use the lower part of the band due to technology limitations, e.g. 3-7GHz
• Next generation will extend this bandwidth e.g. to 3-10GHz, older systems using the energy in 3-7GHz band.
3 4 5 76 98 10 11
Frequency (GHz)
UNII
July 2003
Didier Helal and Philippe Rouzet, STMSlide 14
doc.: IEEE 802.15-03/139r4
Submission
Example of a full band pulse shape
BW-10dB = 7.26 GHzAverage TX power = 0.3 mW
Peak emission power in 50MHz = -10 dBm
July 2003
Didier Helal and Philippe Rouzet, STMSlide 15
doc.: IEEE 802.15-03/139r4
Submission
Example of a low band pulse shape
BW-10dB = 4 GHzAverage TX power = TBD mW
Peak emission power in 50MHz = TBD dBm
July 2003
Didier Helal and Philippe Rouzet, STMSlide 16
doc.: IEEE 802.15-03/139r4
Submission
FRAME: Known Training Sequencefor Frame Synchronization and Channel Estimation
Example of a simplified emitted pulse train
Pulse shape not shown (use rectangle for clarity)
Preamble Modulated user data
Time Hopping + Polarity
2-PPM + Polarity (Time Hopping optional)
PRP
Frame
Frame Preamble
July 2003
Didier Helal and Philippe Rouzet, STMSlide 17
doc.: IEEE 802.15-03/139r4
Submission
BEACON is a regular frame with appended preamble for Coarse Synchronization
Piconet Information
Time Hopping + Polarity
2-PPM + Polarity (Time Hopping optional)
PRP
Time Hopping + Polarity
Coarse Sync. Frame Sync.+ Ch. Est
Beacon
Beacon Preamble
July 2003
Didier Helal and Philippe Rouzet, STMSlide 18
doc.: IEEE 802.15-03/139r4
Submission
Cell synchronization (1)
PNC
DEV-A
DEV-B
Scenario
Cell s
ynch Cell synch
Dev-dev synch
A device which enters the piconet has to
1) Detect the piconet code
2) Find approximate beginning of beacon data
3) Estimate its clock drift with PNC
4) Channel estimation and fine synchronization to allow best energy capture
5) Compensate for residual clock drift
July 2003
Didier Helal and Philippe Rouzet, STMSlide 19
doc.: IEEE 802.15-03/139r4
Submission
Cell synchronization (2)1. Coarse synchronization
1.1 Detection of the piconet code among 20 possible.
1.2 Alignment: find the end of the superframe beacon preamble. Goal is also to find the beginning of the channel impulse response. This is done by detecting the first path above a fixed threshold. May lead to some uncertainties (thus operation is called ‘coarse’).
2. Coarse clock drift correction, based on information given in 1.2. Is made based on several superframe beacon preambles. Use of basic interpolation or adaptive filtering (like Kalman, should the oscillator spec require it) to predict clock drift.
3. Fine synchronization: can take place now, with better accuracy, since some of the clock drift between PNC and DEV has been removed in 2. Via channel estimation and processing, can align to the beginning of the channel impulse response with much more accuracy than after 1.2.
4. Fine clock drift correction, based on information given in 3.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 20
doc.: IEEE 802.15-03/139r4
Submission
Coarse Synchronization (1)
Preamble coding :
TIME HOPPING + POLARITY
Preamble codes :
Sequences of length Lc = 79
TH = Quadratic-Congruence (QC) sequences
Cn = time-hopping offset (multiple of time-hopping resolution)
POL = Derived from row of a Hadamard matrix of size 80 x 80
79mod)*( 2)( nic in • i = 1,2,…,78: sequence number
• n = 0,1,…,78: TH offset index
July 2003
Didier Helal and Philippe Rouzet, STMSlide 21
doc.: IEEE 802.15-03/139r4
Submission
Coarse Synchronisation (2)
• Preamble construction•PRP = 8 ns. TH offset resolution: 50ps.
•Sequence is repeated R = 120 + 3 times.
•Duration of coarse sync beacon preamble: DC = R*LC *PRP = 77.7 s.
…..
120 repetitions
End of Beacon Preamble (EOBP) signature
Beacon preamble duration: DC = 77.7 s
One sequence: LC*PRP
+
--
++
July 2003
Didier Helal and Philippe Rouzet, STMSlide 22
doc.: IEEE 802.15-03/139r4
Submission
Coarse Synchronisation (3)
Contention Free Period
MC
TA
1
CT
A
1
MC
TA
n
C
TA
2
CT
A
m
pre
amb
le
hea
der
bo
dy
Beacon
CT
A
x
Contention
Access
Period
Superframe N
pre
amb
le
Detection : Find one sequence among 20
Alignement : Find end of coarse synchronization beacon preamble with a precision of ~10 ns.
Superframe N+1
… … … …
pre
amb
le
July 2003
Didier Helal and Philippe Rouzet, STMSlide 23
doc.: IEEE 802.15-03/139r4
Submission
Coarse Clock Synchronization (1)
Contention Free Period
MC
TA
1
CT
A
1
MC
TA
n
C
TA
2
CT
A
m
pre
amb
le
hea
der
bo
dy
Beacon
CT
A
x
Contention
Access
Period
Superframe N
pre
amb
le
Superframe N+1
… … … …
pre
amb
le
correct clock drift between TX DEV and RX DEV
pre
amb
le
TSF: average superframe period (e.g. 10 ms)
slope of clock drift = ((ti+1 – ti) – TSF)/TSF
ti+1 ti
July 2003
Didier Helal and Philippe Rouzet, STMSlide 24
doc.: IEEE 802.15-03/139r4
Submission
Coarse Clock Synchronization (2)
Coarse Drift estimation and tracking
• Clock tracking algorithm uses coarse synchronization ouptuts to predict clock drift over next superframe, by basic interpolation or implementing an adaptive filter (like Kalman, should the oscillator spec require it).
• Drift correction down to ~1 ppm. Enough for fine synchronization & channel estimation, done over 6 s.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 25
doc.: IEEE 802.15-03/139r4
Submission
Fine Synchronization
Contention Free Period
MC
TA
1
CT
A
1
MC
TA
n
C
TA
2
CT
A
m
pre
amb
le
hea
der
bo
dy
Beacon
CT
A
x
Contention
Access
Period
Superframe N
pre
amb
le
Superframe N+1
… … … …
pre
amb
le
DEV-A synchronized to PNC’s clock
DEV-A demodulates beacon Fine Synchronisation is made jointly with channel
estimation and optimizes energy capture
Fine synchronization algorithm gives end of beacon preamble (blue) with good accuracy
July 2003
Didier Helal and Philippe Rouzet, STMSlide 26
doc.: IEEE 802.15-03/139r4
Submission
Fine Clock Synchronization
Fine clock drift estimation and tracking
• Clock tracking algorithm uses fine synchronization ouptuts to refine clock drift prediction down to 0.1ppm. Enough for demodulation over 100 s
Contention Free Period
MC
TA
1
CT
A
1
MC
TA
n
C
TA
2
CT
A
m
pre
amb
le
hea
der
bo
dy
Beacon
CT
A
x
Contention
Access
Period
Superframe N
pre
amb
le
Superframe N+1
… … … …
pre
amb
le
pre
amb
le
July 2003
Didier Helal and Philippe Rouzet, STMSlide 27
doc.: IEEE 802.15-03/139r4
Submission
DEV-to-DEV Synchronization (1)
Contention Free Period
MC
TA
1
CT
A
1
MC
TA
n
C
TA
2
CT
A
m
pre
amb
le
hea
der
bo
dy
Beacon
CT
A
x
Contention
Access
Period
Superframe N
Body
Frame sent to DEV-A by DEV-B
Hea
de
r
Pre
am
ble
pre
amb
le
Superframe N+1
… … … …
pre
amb
le
DEV-A wakes up, and needs to synchronize to DEV-B’s clock.
DEV-A’s clock is synchronized to DEV-B’s clock, and can start to demodulate the data contained in the frame sent by DEV-B.
1) Clock drift is known and can be corrected
2) Fine Synchronisation and channel estimation
3) Demodulation
July 2003
Didier Helal and Philippe Rouzet, STMSlide 28
doc.: IEEE 802.15-03/139r4
Submission
DEV-to-DEV Synchronization (2)
f1 and f2 are estimated during cell synchronization phase, by DEV-1 and DEV-2 respectively
f12 is known by PNC and must be corrected by DEVs
PNC
DEV-1TX
DEV-2RX
f1f2
f12
July 2003
Didier Helal and Philippe Rouzet, STMSlide 29
doc.: IEEE 802.15-03/139r4
Submission
DEV-to-DEV Synchronization (2)Two solutions
1. RX DEV corrects for both f1 and f2.
+ Better precision
- MAC needs to provide f values to all piconet devices.
2. TX DEV correct f1 by adjusting pulse position transmission
+ RX DEV does not need to know f1
- Less precise
July 2003
Didier Helal and Philippe Rouzet, STMSlide 30
doc.: IEEE 802.15-03/139r4
Submission
PHY-SAP Data Throughput close to Payload Bit Rate
PHY Header, MAC Header (802.15.3 format), HCS use 62.5Mb/s mode
Optimized Packet Overhead Times
Payload Bit Rate (Mb/s)
PHY-SAP Throughput (Mb/s) 5 frames
PHY-SAP Throughput (Mb/s) 1 frame
T_DATA
(1020 Bytes MPDU)
62.5(mandatory) 58.26 56.9 132.68 s
125 (mandatory) 109.49 106.27 66.34 s
250 (optional) 195.4 188.25 33.04 s
500 (optional) 321.56 301.8 16.79 s
T_PA_
INITIAL
T_PHYHDR
T_MACHDR
T_HCS T_MIFS T_SIFS T_PA_
CONT
T_RIFS
6 s 0.26s 1.3 s 0.26s 1s 2 s 6 s 4 s
July 2003
Didier Helal and Philippe Rouzet, STMSlide 31
doc.: IEEE 802.15-03/139r4
Submission
MAC enhancements
Proposed MAC is compliant with existing MAC IEEE 802.15.3
• Introduction of optional minor MAC adaptations to optimize– Receiver power consumption– Complexity (synchronization)– Performance (ARQ)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 32
doc.: IEEE 802.15-03/139r4
Submission
Frame reception (1)• Approximate frames Times Of Arrival (TOAs) used
in CTA slots
TOA information announced by source DEV at the begining of CTA
– Used for channel estimation & synchronization
– Several ways of TOA signaling possible (i.e. one example presented after)
– Benefits :
• ARQ scheme can be improved (One ACK per CTA to lower overhead)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 33
doc.: IEEE 802.15-03/139r4
Submission
Proposed TOA used by MAC for Frame synchronization
•Use of approximate frame TOAs to manage different lengths of frames and facilitate frame synchronization
CTA slot in superframe
Frame 1 MIF
SFrame 2 M
IFS
MIF
S
MIF
S
3 Frame 4 Frame 5
MIF
S
6
MIF
S
TO
A 1
TO
A 2
TO
A 3
TO
A 4
TO
A 5
TO
A 6
TOA 1 TOA 2 TOA 3 TOA 4 TOA 5 TOA 6
MIF
S
CTA Header announcing TOAs
July 2003
Didier Helal and Philippe Rouzet, STMSlide 34
doc.: IEEE 802.15-03/139r4
Submission
Frame reception (2)
• Randomized access without CAP
Use MCTA slots and Slotted Aloha instead of CAPVERY LOW POWER CONSUMPTION
• Randomized access within CAP without CSMA/CA
Use CAP with a new Slotted mechanismLOW POWER CONSUMPTION
• Randomized access within CAP with CSMA/CA
Use CAP as defined in 802.15.3: CSMA/CA with CCA
July 2003
Didier Helal and Philippe Rouzet, STMSlide 35
doc.: IEEE 802.15-03/139r4
Submission
Randomize access within CAP• CSMA/CA in CAP is possible by CCA through preamble
detection but not efficient– CCA consumes a lot of energy (due to UWB environment, true for
all PHY layer proposals and not only STM one)– Not suitable for time-bounded consumer applications (audio/video
streaming)
• Better solution is to do CCA by Slotted CAP mechanism
20ns 20ns 20ns 20ns 20ns
10μs 10μs 10μs 10μs
…
CAP
July 2003
Didier Helal and Philippe Rouzet, STMSlide 36
doc.: IEEE 802.15-03/139r4
Submission
Proposed Alternate PHY enables
Single Chip FULL CMOS solution
Through
DIRECT SAMPLING on 1 BITand
DIGITAL MATCHED FILTERINGLearn pulse signature after channel propagation
July 2003
Didier Helal and Philippe Rouzet, STMSlide 37
doc.: IEEE 802.15-03/139r4
Submission
Demodulation is performed by Match-Filtering
The match-filter is the estimate of the pulse signature through channel propagation
No pulse shape is assumed by receiver !
Take advantage of multi-path (complete immunity)
Match-filtering
Compound Channel Response
Average
Demodulation
Channel Estimation
Tx signalRx signal
Channel+ Noise
July 2003
Didier Helal and Philippe Rouzet, STMSlide 38
doc.: IEEE 802.15-03/139r4
Submission
Channel estimation chain• Picture shows E/No = 6dB• Time window is 50ns and 1ns 1 bit ADC
Noise injection
Average of 750 pulses (1-bit
sampled)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 39
doc.: IEEE 802.15-03/139r4
Submission
Channel estimation
• The channel estimated is compared with the actual channel response
• Averaging 1 bit data remove noise and gets accurate estimation
July 2003
Didier Helal and Philippe Rouzet, STMSlide 40
doc.: IEEE 802.15-03/139r4
Submission
Channel estimation easy to implement• Each point of the channel estimation can be seen as one finger of a rake
receiver64 ns = 1280 fingers of 50 ps width
• Channel estimation consists in coherent integration of received pulses.
One bit ADC makes the operation a simple increment/decrementNo multiplication or complex operator !
• Estimated gate count of the whole channel estimation block
bit slice number of gates * number of bit of the counter * number of channel point(20*7*1280 = 179200 gates)
• Power consumption
Parallel hardware implementation of all fingersFrequency of operations is low (1/PRP)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 41
doc.: IEEE 802.15-03/139r4
Submission
RF block
Antenna
BPFilter
Pulse
Generator
Clock
Synthesizer
1-bit
ADC
TDD
Switch
ABR
ABR
Optional
LNA
PTC
UWB System-on-ChipBlock Diagram
Channel estimation
Synchronization
DemodulationChannel
Decoding
Channel
Coding
Modulation &
coding
Baseband block
TX
Data
RX
Data
TX
Preparation
Frag-mentation
TX
Control
RX
Control
Defrag-
mentation
MAC block (Bottom part)
PTC
ABR = Adaptive Band RejectionPTC = Piconet Time Control
MAC+BB+RF on same silicon except BP filter and Antenna
July 2003
Didier Helal and Philippe Rouzet, STMSlide 42
doc.: IEEE 802.15-03/139r4
Submission
Link Budget
Noise figure for all RX chain referred at the antenna output
Implementation loss = jitter effect <2dB (varies with pulse shape) + 2dB margin in order to enable simplest demodulation
Antenna
BPFilter
Pulse
Generator
Clock
Synthesizer
1-bit
ADC
TDDSwitch
ABR
ABR
Optional
LNA
2dBloss
0.5dBloss
NF = 3dB2dB
G = 16dB
NF = 9dB
Clock Jitter : 10ps rms (maximum from 0.13m silicon measurements)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 43
doc.: IEEE 802.15-03/139r4
Submission
Performances Summary
• The following results are voluntary based on- 3-7GHz pulse instead of 3-10GHz- Convolutional coding instead of Turbo Coding
July 2003
Didier Helal and Philippe Rouzet, STMSlide 44
doc.: IEEE 802.15-03/139r4
Submission
110Mbps @ 10m, AWGNThroughput Rb (Mb/s) 125Distance (m) 10.0Average TX power Pt (dBm) -5.58Tx antenna gain Gt (dBi) 0.0Fc (Hz) 4.9E+09Path loss 1 meter L1 (dB) 46.2Path loss at d meter L2 (dB) 20.0Rx antenna gain Gr (dBi) 0.0Rx power Pr (dBm) -71.7N = -174 + 10*LOG10(Rb) (dBm) -93.0Noise Figure (dB) 6.1Average noise power per bit Pn (dBm) -86.9Eb/No min (dB) TBDImplementation Loss (dB) 4.0Link Margin (dB) #######Proposed Min Rx sensitivity Level (dBm) #######
MAXIMUM RANGE
TBD m
EFFECTIVE THROUGHPUT
125 Mbps
RESULTS INCLUDE SHADOWING
July 2003
Didier Helal and Philippe Rouzet, STMSlide 45
doc.: IEEE 802.15-03/139r4
Submission
200Mbps @ 4m, AWGN
MAXIMUM RANGE
TBD m
EFFECTIVE THROUGHPUT
250 Mbps
Throughput Rb (Mb/s) 250Distance (m) 4.0Average TX power Pt (dBm) -5.58Tx antenna gain Gt (dBi) 0.0Fc (Hz) 4.9E+09Path loss 1 meter L1 (dB) 46.2Path loss at d meter L2 (dB) 12.0Rx antenna gain Gr (dBi) 0.0Rx power Pr (dBm) -63.8N = -174 + 10*LOG10(Rb) (dBm) -90.0Noise Figure (dB) 7.0Average noise power per bit Pn (dBm) -83.0Eb/No min (dB) TBDImplementation Loss (dB) 4.0Link Margin (dB) #######Proposed Min Rx sensitivity Level (dBm) #######
RESULTS INCLUDE SHADOWING
July 2003
Didier Helal and Philippe Rouzet, STMSlide 46
doc.: IEEE 802.15-03/139r4
Submission
480Mbps @ 1m , AWGN
MAXIMUM RANGE
TBD m
EFFECTIVE THROUGHPUT
500 Mbps
Throughput Rb (Mb/s) 500Distance (m) 1.0Average TX power Pt (dBm) -5.58Tx antenna gain Gt (dBi) 0.0Fc (Hz) 4.9E+09Path loss 1 meter L1 (dB) 46.2Path loss at d meter L2 (dB) 0.0Rx antenna gain Gr (dBi) 0.0Rx power Pr (dBm) -51.7N = -174 + 10*LOG10(Rb) (dBm) -87.0Noise Figure (dB) 6.1Average noise power per bit Pn (dBm) -80.9Eb/No min (dB) TBDImplementation Loss (dB) 4.0Link Margin (dB) #######Proposed Min Rx sensitivity Level (dBm) #######
RESULTS INCLUDE SHADOWING
July 2003
Didier Helal and Philippe Rouzet, STMSlide 47
doc.: IEEE 802.15-03/139r4
Submission
55Mbps @ 10m, AWGNThroughput Rb (Mb/s) 62.5Distance (m) 10.0Average TX power Pt (dBm) -5.58Tx antenna gain Gt (dBi) 0.0Fc (Hz) 4.9E+09Path loss 1 meter L1 (dB) 46.2Path loss at d meter L2 (dB) 20.0Rx antenna gain Gr (dBi) 0.0Rx power Pr (dBm) -71.7N = -174 + 10*LOG10(Rb) (dBm) -96.0Noise Figure (dB) 6.1Average noise power per bit Pn (dBm) -89.9Eb/No min (dB) TBDImplementation Loss (dB) 4.0Link Margin (dB) #######Proposed Min Rx sensitivity Level (dBm) #######
MAXIMUM RANGE
TBD m
EFFECTIVE THROUGHPUT
62.5 Mbps
RESULTS INCLUDE SHADOWING
July 2003
Didier Helal and Philippe Rouzet, STMSlide 48
doc.: IEEE 802.15-03/139r4
Submission
Coding Performances in CM4 channelcoding PRP #PPM Code rate Data rate # operations Eb/No
TC - RSC [13,15] 8ns 4 1/3 125Mbps equivalent dB
CC - [133,171] 8ns 2 1/2 125Mbps equivalent dB
For similar complexity
Using a convolutionnal coding
instead of a Turbo coding results in a
1.4dB loss in performances
July 2003
Didier Helal and Philippe Rouzet, STMSlide 49
doc.: IEEE 802.15-03/139r4
Submission
• Coexistence with in-band systems ensured by TX pulse shaping or filtering
– System is independent from pulse shape
• Transmit power control reduces interferences
– Helped by location awareness capability (distance can be estimated with 3cm resolution)
• No impact on current regulation
– FCC’s Part 15 rules followed
– Additional spectrum protection
can be supported
• 802.15.3 Power Management modes are supported
(DSPS, PSPS, APS)
Coexistence and regulatory impact
July 2003
Didier Helal and Philippe Rouzet, STMSlide 50
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsSingle Interferer
TX DEV
RX DEV
Interferer
dint
CM1, CM2, CM3 or CM4multipath channel
dref
CM1, CM2, CM3 or CM4
multipath channel
Rx level = (limit PER=8%) + 6dB
Modulation : 2-PPM, Prp = 8 ns,CR 1/2, 125 MbpsContinuous overlapping interferer transmission (worst condition)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 51
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsSingle piconet interferer
• Dref/Dint is better than TBD (for 125 Mbps modulation)– CM3, CM4 supports interferer @ ~TBD meters for a Ref source
@ 10 meters– Interfering channel slightly impacts performance (better for low
density channel such as CM1 and CM2, instead of CM3,CM4) -> meters instead of meters
– Pulse BW impact performances Dref/Dint ~ (BW)– PRP or Datarate impact performances Dref/Dint ~ (PRP) using the
same modulation scheme, just changing PRP (and along the datarate)• Gracefull degradation of performance in case of strong UWB
interferer by adjusting PRP
July 2003
Didier Helal and Philippe Rouzet, STMSlide 52
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsEffect of TH
• Effect of Time hopping in modulated data on interferer immunity– Small effect, equivalent of ~0.1 dB
– Effect is marginal on average but smooth some worst case
• Marginal improvement for a marginal added complexity– TH may be kept as on option in standard (TBD)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 53
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsMultiple Piconet interferers
TX DEV
RX DEV
dint
CM3 or CM4multipath channel
dref
Free space channel
Rx level = (limit PER=8%) + 6dB
3 Interferers
Modulation : 2-PPM, Prp =8 ns,CR 1/2, 125 MbpsContinuous overlapping interferer transmission (worst condition)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 54
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsMultiple piconet interferer
• Multiple Interferer use free space channel
– Low width of pulse means small effect on receiver
– Infinite rake architecture and 1 bit sampling gives strong performance here
• 2 Interferers : Dref/Dint is better than TBD (for 125 Mbps modulation)
– CM1, CM2, CM3, CM4 supports 2 interferers @ ~TBD meters for a Ref source @ 10 meters
• 3 Interferers : Dref/Dint is better than TBD (for 125 Mbps modulation)
– CM3, CM4 supports 3 interferers @ ~TBD meters for a Ref source @ 10 meters
July 2003
Didier Helal and Philippe Rouzet, STMSlide 55
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsMultiple piconet interferer
July 2003
Didier Helal and Philippe Rouzet, STMSlide 56
doc.: IEEE 802.15-03/139r4
Submission
Interference and Susceptibility
• Performances in a simple configuration : fixed UNII notch filter that can be bypassed.
• All out-of-band interferers supported (according to IEEE 802.15-3a proposed criteria).
July 2003
Didier Helal and Philippe Rouzet, STMSlide 57
doc.: IEEE 802.15-03/139r4
Submission
PAYLOAD Bit Rate Target
PAYLOAD Bit Rate Effective
Modulation Code-rate PRP Power Consumption
55 Mbps 62.5 Mbps Pol 1/2 8 ns TBD mW
110 Mbps 125 Mbps Pol+2ppm 1/2 8 ns TBD mW
200 Mbps 250 Mbps Pol+4ppm 2/3 8 ns TBD mW
480 Mbps 500 Mbps Pol+4ppm 2/3 4 ns TBD mW
Power Consumption estimates
Hypothesis : convolutional coding, channel estimation operating during 10% of time
July 2003
Didier Helal and Philippe Rouzet, STMSlide 58
doc.: IEEE 802.15-03/139r4
Submission
Gate count & Consumption calcul (1/2)Example with the Channel Estimation
• Each point of the channel estimation can be seen as one finger of a rake receiver.(I.e. 64 ns = 1280 fingers of 50 ps width)
• The channel estimation consists to integrate coherently pulses. As the front-end is a one bit ADC, for each point of the channel, the operation is simply an increment/decrement.(I.e 1280 Inc/Dec for each pulse in TS, 1000 pulses -> 1.2 M Inc/Dec, No multiplication or complex operator !)
• Estimated gate count : – We need about 20 gates for each bit slice of an up-down counter : on flip-flop, and add-
sub and a few more for count gating.– So the gate count of the whole channel estimation block is : 20 * number of bit of the
counter * number of point of the channel(Using parallel hardware implementation of each finger, to keep low clock rate of 1/PRP)
• Consumption : – As the increment/decrement operation needs to be done only at each pulse the frequency
is 1/PRP.– The estimation of the consumption in 0.13 m is 6 nW/Gate/MHz
July 2003
Didier Helal and Philippe Rouzet, STMSlide 59
doc.: IEEE 802.15-03/139r4
Submission
Gate count & Consumption calcul (2/2)Data Rate (Convolutional Code)Channel Length (ns) 1
Number of Coherent Integration 2
PPM Number 3
Minimum PRP (ns) 4
Bit Rate (Mbits/sec)
Area/Gates Consumption Area/Gates Consumption
RF Transmitter (mm 2 - mW) 1.5 40 1.5 40Digital Transmitter (gates - mW) 20000 15 20000 15
Total Transmitter (mm2 - mW) 1.6 55 1.6 55
RF Receiver (mm 2 - mW) 1.5 70 1.5 70Digital RX Time Hopping Processing (gates - mW) 17920 13.44 17920 13.44Digital RX Channel Estimation (gates - mW) 174080 130.56 174080 130.56Digital RX Demodulation (gates - mW) 35840 26.88 71680 53.76Digital RX Channel Decoding (gates - mW) 50000 37.5 50000 37.5
Total Receiver 5 (mm2 - mW) 2.9 158.2 3.1 182.4
5 : The total consumption supposed that the channel estimation is in operation during 10% of active time and the demodulation and channel decoding 90% of active time
1 : The Channel Length parameter correspond to the windows on which the channel estimation and demodulation is performed.2 : NCI is the number of coherent integration done for the demodulation.3 : PPM number is the number of position for the pulse modulation. There is as many metric block as PPM4 : The minimum PRP (Pulse Repeating Period) indicate directly the max frequency of the chip.
8 8250 375
128 128
2 4
125 Mbits/sec 250 Mbits/sec64 64
July 2003
Didier Helal and Philippe Rouzet, STMSlide 60
doc.: IEEE 802.15-03/139r4
Submission
Power saving optimization
• Simulations show that doing a channel estimation on 30 ns for CM1 and CM2 is sufficient (ie. no impact on performance). For a 4 PPM system, the consumption of the baseband part would then be of 72 mW instead of 112 mW.
• For CM3 and CM4, simulations shows that 50 ns is sufficient. For a 4 PPM system, the consumption would be 90mW instead of 112 mW.
• Note that having a channel of 64 ns allows to shorten the synchronization time.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 61
doc.: IEEE 802.15-03/139r4
Submission
Very Low Cost Architecture : Sampling at 14 GHz
• In our presentation we use a one bit sampler at 20 GHz. But it still possible to use a one bit sampling at a lower frequency : simulations using a sampler at 14 GHz shows a loss on performances of only 0.5 dB
• On the baseband part (without the channel decoding) this allows to reduce the size and the power consumption : with 4 PPM, we have 0.9 mm2 and 53.5 mW instead of 1.3 mm2 and 75 mW.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 62
doc.: IEEE 802.15-03/139r4
Submission
Choice of sampling RATE
• Sampling frequency is defined by implementer– 20 GHz for top
performance– 14 GHz for low end
product (0.5 dB loss from 20 GHz for 3-7 GHz pulse, simulation done with CM1 channel, at 125 Mbps datarate)
– Lower sample frequency possible but larger loss (undersampling of pulse bandwidth)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 63
doc.: IEEE 802.15-03/139r4
Submission
Current Demonstrator Platform
• RF transmitter and receiver : ASIC. – First chipset already in test– Full chipset on September 2003
• Baseband – Today : off-the-shelves board (Nallatech BenNuey) with FPGA
Xilinx Virtex2 6000– End of 2003 : ASIC 0.13 m
• Current progress in demonstrator shows low risk manufacturability (Baseband in FPGA today implies easy migration to ASIC, RF already in test)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 64
doc.: IEEE 802.15-03/139r4
Submission
Lay-out of the clock generation block
CMOS 0.13m
July 2003
Didier Helal and Philippe Rouzet, STMSlide 65
doc.: IEEE 802.15-03/139r4
Submission
FPGA Floorplaning and Routing
Current estimates on gate count
and power consumption are
based on real implementation
Design Information------------------Target Device : x2v6000Target Package : bf957Target Speed : -4Mapper Version : virtex2 -- $Revision: 1.4 $Mapped Date : Fri May 09 11:15:23 2003
Design Summary-------------- Number of errors: 0 Number of warnings: 0
Number of Slices: 25,606 out of 33,792 75% Number of Slices containing unrelated logic: 0 out of 25,606 0% Number of Slice Flip Flops: 6,298 out of 67,584 9% Total Number 4 input LUTs: 36,944 out of 67,584 54% Number used as LUTs: 33,305 Number used as a route-thru: 3,639 Number of bonded IOBs: 93 out of 684 13% IOB Flip Flops: 67 Number of GCLKs: 1 out of 16 6%
July 2003
Didier Helal and Philippe Rouzet, STMSlide 66
doc.: IEEE 802.15-03/139r4
Submission
Easy Manufacturability and attractive form factor
• Full system can be built in CMOS technology– single chip– Die size estimated at less than 5mm2 in 0.13m
• Antenna size : expected 3cm x 3cm (printed PCB)
• Time to Market can be less than 1.5 years !
July 2003
Didier Helal and Philippe Rouzet, STMSlide 67
doc.: IEEE 802.15-03/139r4
Submission
CRITERIA REF LEVEL STM RESPONSE
General Solution Criteria
Unit Manufacturing Complexity 3.1 B + Low - Single chip solution
Signal Robustness
Interference and Susceptibility 3.2.2 A + Out-band and In-band Interferers
rejected at down to TBD m
Coexistence 3.2.3 A + Pulse shaping or filtering
Technical Feasibility
Manufacturability 3.3.1 A + Easy - full CMOS
Time To Market 3.3.2 A + 1.5 year
Regulatory Impact 3.3.3 A + Flexible emitted pulse shape
Scalability 3.4 C + Scalable data rates, ranges and
power consumption
Location awareness 3.5 C + Supported + built in “hooks”
MAC Protocol Enhancement Criteria
MAC Enhancements And Modifications 4.1 C + Compliant
July 2003
Didier Helal and Philippe Rouzet, STMSlide 68
doc.: IEEE 802.15-03/139r4
Submission
CRITERIA REF. LEVEL STM RESPONSE
PHY Protocol Criteria
Size And Form Factor 5.1 B + Single Chip 5mm2
PHY-SAP Payload Bit Rate & Data Throughput
Payload Bit Rate 5.2.1 A + All rates supported up to 0.5Gbps (+Low Data Rates)
PHY-SAP Data Throughput 5.2.2 A + Short preamble and inter-frame space
Simultaneously Operating Piconets 5.3 A + Different preambles for piconets
TH+polarity code division
Signal Acquisition 5.4 A + Short synchronization time
(good sequence/continuous sampling)
Link Budget 5.5 A + Margin is TBD dB at 10m (2dB for lowest complexity)
Sensitivity 5.6 A + TBDdBm (TBD dBm for lowest complexity) @110Mbps
+ TBDdBm (TBDdBm for lowest complexity) @55Mbps
Multi-Path Immunity 5.7 A + Channel Estimation + Matched-Filter
Retrieves all energy
Power Management Modes 5.8 B + All modes supported
Power Consumption 5.9 A + Very Low. ADC already scaled for highest data-rates
Antenna Practically 5.10 B + 3cmx3cm printed
July 2003
Didier Helal and Philippe Rouzet, STMSlide 69
doc.: IEEE 802.15-03/139r4
Submission
Proposal matches all criteria
at
Very Low Cost
and
Very Low Power Consumption
Thank you for your attention
Questions are welcome…
July 2003
Didier Helal and Philippe Rouzet, STMSlide 70
doc.: IEEE 802.15-03/139r4
Submission
BACKUP SLIDES
July 2003
Didier Helal and Philippe Rouzet, STMSlide 71
doc.: IEEE 802.15-03/139r4
Submission
Monopulse Adaptive band PPM assets• Theoretical capacity is linear with BW• Per bit energy maximized (for a given datarate and
spectrum limit) • Simultaneously operating piconets supported
UWB interference rejection varies along with BW.PRP product
Given a modulation scheme, dref/dint ~ sqrt(BW)
• Synchronizationuse of full BW, good energy level available, short sequence possible, fine synch and channel estimation optimized joint process
• Good localization ability thanks to better channel time resolution
• Less fading issues, optimal energy capture (using infinite rake architecture)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 72
doc.: IEEE 802.15-03/139r4
Submission
Monopulse Adaptive band assets
• Pulse shape (so BW) is not hard coded in standard
• Backward compatibility between technology generationsE.g. 3.1-7GHz in 0.13um and 3.1-10.6GHz in 90nm
• Flexible data rate : PRP is easily changed
• Compatibility between High and Low Data Rate devices
• Complexity decreases along with data rate
• Power consumption decreases with data rate
July 2003
Didier Helal and Philippe Rouzet, STMSlide 73
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsSingle piconet interferer : Hypothesis
• Simulation hypothesis– Reference link is a multipath channel in CM3 or CM4 (CM1 and CM2 are
short range and “easy case”, no near far, so not considered for first simulations), several (5) channels of each CM are used
– Rx level is tuned to get 6 dB above the limit of 8% PER (limit level is known from performance simulation as Eb/No for the current simulated channel, 200+ packets simulated to get the reference)
– Interferer level is set from dint simulated (P.d² is constant, and Tx power is same for Ref and for interferer)
– Interferer channel is a multipath channel in CM1,2,3 or 4 (5 channels of each are used)
– Modulation used is 2-PPM, Prp =8 ns, CR 1/2, 125 Mbps
– Simulation operation : dint is tuned to get the reference PER limit of 8% (only the WORST case ratio of distance : dref /dint is kept as result)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 74
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsSingle piconet interferer
• Simulation results P1(3-10GHz) at Eb/No ~ dBWorst case ratio
Dref/dint
(= Near far factor)
Int is CM1 Int is CM2 Int is CM3 Int is CM4
Ref is CM1
(5 channels used)
Ref is CM2
(5 channels used)
Ref is CM3
(5 channels used)
Ref is CM4
(5 channels used)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 75
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsSingle piconet interferer
• Simulation results P2 (3-7GHz) at Eb/No ~ dBWorst case ratio
Dref/dint
(= Near far factor)
Int is CM1 Int is CM2 Int is CM3 Int is CM4
Ref is CM1
Ref is CM2
Ref is CM3
(5 channels used)
Ref is CM4
(5 channels used)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 76
doc.: IEEE 802.15-03/139r4
Submission
Simultaneously operating PiconetsMultiple piconet interferers
• Simulation hypothesis– Reference link is a multipath channel in CM3 or CM4 (CM1 and CM2 are
short range and “easy case”, no near far, so not considered for first simulations), several (5) channels of each CM are used
– Rx level is tuned to get 6 dB above the limit of 8% PER (limit level is known from performance simulation as Eb/No for the current simulated channel, 200+ packets simulated to get the reference)
– Interferer level is set from dint simulated (P.d² is constant, and Tx power is same for Ref and for interferer)
– 2 or 3 independent UWB source interferers– Interferer channel is a free space channel– Modulation used is 2-PPM, Prp =8 ns, CR 1/2, 125 Mbps
– Simulation operation : dint is tuned to get the reference PER limit of 8% (only the WORST case ratio of distance : dref /dint is kept as result)
July 2003
Didier Helal and Philippe Rouzet, STMSlide 77
doc.: IEEE 802.15-03/139r4
Submission
Channel Estimation Algorithm
• The channel response is estimated with the training sequence
• Coherent integrations (on the received pulses) reduces noise and ISI effects.
• Most of channel energy is recovered by so.
• SNR at RX is good enough to reduce PRP and to increase data rate.
• System is independent from transmitted pulse shape – No need for Pulse Template
July 2003
Didier Helal and Philippe Rouzet, STMSlide 78
doc.: IEEE 802.15-03/139r4
Submission
NPPM Correlations
APP calculations
N-PPM (number of Pulse positions) soft values corresponding to each PPM position at Pulse Repetition Frequency.
Channel estimation
RF DeinterleavingBL=BTC/C
depuncturechannel decoder
(Turbo decoder or Viterbi decoder)
channel decoding architecture
descrambling
Uncorrelates bit errors at the input of the decoder :C=code rateBTC=Turbo code block length.
Adds scalability
demapping and soft A priori per bit Probability calculations.
July 2003
Didier Helal and Philippe Rouzet, STMSlide 79
doc.: IEEE 802.15-03/139r4
Submission
Turbo code
• Latency is mainly due to the storage of one block into the channel de-interleaver.
@110Mbps: 512/110e6~5us.@ 55Mbps: 512/55e6=10us.
• Complexity: – RAM: 50 000 bits.– ~500 kGates
July 2003
Didier Helal and Philippe Rouzet, STMSlide 80
doc.: IEEE 802.15-03/139r4
Submission
Performance Indicators
• False Alarm probability (PFA): a preamble is detected where there is none
A target PFA ~ 10-4 is assumed
• Missed Detection probability (PMD): the preamble is not detected
A target PMD ~ 10-4 is assumed
• Beacon training sequence length ~ overhead percentage ~ synchronization time
Hypotheses
• No clock jitter present
• No clock drift present
• Send at max power allowed by FCC
• PRP = 10.8 ns
• Superframe ~= 10 ms
• CM3 channels utilised
• Most proposed pulse shapes will do
• Dimension preamble sequence for worst conditions: 110 Mbps @ 10m
Coarse synchronization
July 2003
Didier Helal and Philippe Rouzet, STMSlide 81
doc.: IEEE 802.15-03/139r4
Submission
• First step: Preamble Detection
- Goal: search sequentially one sequence among 20 possible.
- Done over the first 120 repetitions of the QCH sequence.
- If piconet present and SNR >~ -7dB: Integration over 3 repetitions of the QCH sequence is enough. Sequence will be detected within 10 ms (at most 2 superframe beacons necessary).
- If piconet present but bad radio conditions: need to combine 4 or more QCH sequences to achieve detection.
• Second step: Alignment
- Goal: find end of beacon preamble.
- Done with aid of EOBP signature. Try to correlate with last 5 replicas of the beacon preamble: [+1 +1 –1 –1 +1].
Coarse Sync: Timeline
July 2003
Didier Helal and Philippe Rouzet, STMSlide 82
doc.: IEEE 802.15-03/139r4
Submission
Coarse sync: pulse comparison
SNR [dB]
PRP = 5.4 ns, L = 237, THR = 111 CM3
-10 -9.5 -9 -8.5 -8 -7.5 -7 -6.5 -6 -5.5 -5
10-4
10-3
10-2
10-1
100
10-5
PM
D
P3.1-10.6, no jitterP3.1-10.6, 10ps jitterP3.1-7, no jitterP3.1-7, 10ps jitter
P3.1-7 - 45, 10ps jitterP3.1-5, no jitterP3.1-5, 10ps jitter
P3.1-7 - 45, no jitter
July 2003
Didier Helal and Philippe Rouzet, STMSlide 83
doc.: IEEE 802.15-03/139r4
Submission
Channel estimation Simulation Results
• Loss due to reduction of training sequence length from 6s to 3s equals 1dB
0 2 4 6 8 10
10-2
10-1
Eb/No
Ser
Cm3 PRP=6ns
NCI=500NCI=1000NCI=750NCI=600
0 2 4 6 8 10 12 14
10-2
10-1
Cm4 PRP=6ns
Eb/No
Ser
NCI=1000NCI=500NCI=600NCI=750
Eb/No
July 2003
Didier Helal and Philippe Rouzet, STMSlide 84
doc.: IEEE 802.15-03/139r4
Submission
Pulse Repetition Period at 110Mb/s
Nbit/Pulse 1 2 3 4 5Modulation POL 2PPM
POL4PPM POL
8PPM POL
16PPM POLCR = 1/3 3 6.05 9.05 12.1 15.15
CR = 1/2 4.5 9.05 13.6 18.15 22.7CR = 2/3 6.05 12.1 18.15 24.2 30.3CR = 3/4 6.8 13.6 20.45 27.25 34.05CR = 7/8 7.95 15.9 23.85 31.8 39.75CR = 1 9.05 18.15 27.25 36.35 45.45CR = Code Rate All PRP values in nanosecond
Low order modulation preferred to minimize gate count/costfor low data-rate devices
July 2003
Didier Helal and Philippe Rouzet, STMSlide 85
doc.: IEEE 802.15-03/139r4
Submission
Pulse Repetition Period at 200Mb/s
Nbit/Pulse 1 2 3 4 5Modulation POL 2PPM
POL4PPM POL
8PPM POL
16PPM POL
CR = 1/3 1.65 3.3 5 6.65 8.3
CR = 1/2 2.5 5 7.45 10 12.45
CR = 2/3 3.3 6.65 10 13.3 16.65
CR = 3/4 3.7 7.45 11.25 14.95 18.7
CR = 7/8 4.35 8.75 13.1 17.5 21.85
CR = 1 5 10 15 20 24.95
CR = Code Rate All PRP values in nanosecond
Low order modulation preferred to enableintermediate data-rate devices
July 2003
Didier Helal and Philippe Rouzet, STMSlide 86
doc.: IEEE 802.15-03/139r4
Submission
Pulse Repetition Period at 480Mb/s
CR = Code Rate All PRP values in nanosecond
Nbit/Pulse 1 2 3 4 5Modulation POL 2PPM
POL4PPM POL
8PPM POL
16PPM POL
CR = 1/3 0.65 1.35 2.05 2.75 3.45
CR = 1/2 1 2.05 3.1 4.15 5.2
CR = 2/3 1.35 2.75 4.15 5.55 6.9
CR = 3/4 1.55 3.1 4.65 6.2 7.8
CR = 7/8 1.8 3.6 5.45 7.25 9.1
CR = 1 2.05 4.15 6.2 8.3 10.4
Larger PRP preferred to avoid too small inter-position delay !
July 2003
Didier Helal and Philippe Rouzet, STMSlide 87
doc.: IEEE 802.15-03/139r4
Submission
Pulse Repetition Period at 1Gb/s
CR = Code Rate All PRP values in nanosecond
Nbit/Pulse 1 2 3 4 5Modulation POL 2PPM
POL4PPM POL
8PPM POL
16PPM POL
CR = 1/3 0.3 0.65 1 1.3 1.65
CR = 1/2 0.5 1 1.5 2 2.5
CR = 2/3 0.65 1.3 2 2.65 3.3
CR = 3/4 0.75 1.5 2.2 3 3.7
CR = 7/8 0.8 1.75 2.6 3.5 4.35
CR = 1 1 2 3 4 5
Larger PRP preferred to avoid too small inter-position delay in PPM
July 2003
Didier Helal and Philippe Rouzet, STMSlide 88
doc.: IEEE 802.15-03/139r4
Submission
Manufacturability• Architecture matches full CMOS implementation
– Low cost, single chip product– Using today’s silicon technology
• Simulation proven hardware architecture– SystemC model used (synthesized model available)– Performance and gate complexity estimated from chipset and
FPGA implementation
• Demonstrator in development– 0.13 m CMOS technology
• Size and form factor– Single chip silicon allows small size like PC card, memory stick,
…, and would be usable in portable devices
July 2003
Didier Helal and Philippe Rouzet, STMSlide 89
doc.: IEEE 802.15-03/139r4
Submission
Power consumption
• Low power Architecture– Minimum RF front end (low power with respect to
alternative architecture)– Demodulation processed in digital– Channel estimation gates (~2/3 of demodulation count)
used only during frame preamble (<10% of time) – Typical clock frequency is PRP (only RF front end is
high speed)– Digital power consumption will scale as Moore’s law
in future technology
July 2003
Didier Helal and Philippe Rouzet, STMSlide 90
doc.: IEEE 802.15-03/139r4
Submission
Scalability
• Low data rate (LDR) permits lower power, lower complexity– Channel estimation power cost can be reduced for low
data rate (need less path, and shorter sequence)
– Simple modulation (polarity) compatible with HDR devices
• High data rate scalable easily– ST expect data rate of up to 750 Mbps shortly
– 1 Gbps theoretically possible for high-end products
July 2003
Didier Helal and Philippe Rouzet, STMSlide 91
doc.: IEEE 802.15-03/139r4
Submission
Location awareness
• Relative location (distance between stations) available at almost no cost– Thanks to channel estimation principle
• 2 performance levels possible (implementor choice)– A few decimeters accuracy (simple processing)– A few centimeters accuracy (signal processing of
estimated channel)– Minimal additional hooks in 802.15.3 MAC
July 2003
Didier Helal and Philippe Rouzet, STMSlide 92
doc.: IEEE 802.15-03/139r4
Submission
Multipath immunity
• Channel estimation principle allows capture of most received energy – Equivalent to infinite rake architecture
• Excellent performance in worst multipath environment
• Pulse shape/spectrum independent– The receiver architecture don’t need a-priori knowledge
on pulse shape (this is why it is so easy to match specific regulation)
– Dense multipath channel with overlapping pulses don’t degrade performance
July 2003
Didier Helal and Philippe Rouzet, STMSlide 93
doc.: IEEE 802.15-03/139r4
Submission
Slotted CAP• CAP period is divided into slots with well-defined slot beginning
– beacon defines CAP duration as well as each slot duration (e.g 10μs)
• Transmitter (Tx) sends frame at the beginning of the slot • Devices consume power to perform CCA (6μs preamble detection) only at the beginning of the
slot – 20ns is uncertainty of frame arrival (thus insured less power consumption than in the case
when the frame can arrive anywhere in 10μs slot assuming STM implementation choices)• Tx receives feedback about frame transmission by means of Imm-ACK• If frame is to be retransmitted, Tx sends frame in randomly selected slot (using a backoff
mechanism)
20ns 20ns 20ns 20ns 20ns
10μs 10μs 10μs 10μs
…
Slotted CAP
July 2003
Didier Helal and Philippe Rouzet, STMSlide 94
doc.: IEEE 802.15-03/139r4
Submission
CCA by preamble detection (optional)
• No assumption on frame start• Frame preamble tuning needed for CCA
– Preamble still periodic but shorter (allows continuous correlation without additional H/W for coarse synch.)
– Preamble includes both coarse and fine synchronization (~10μs)
• Power consumption : same as channel estimation phase (during all CCA period of activity) : mW
July 2003
Didier Helal and Philippe Rouzet, STMSlide 95
doc.: IEEE 802.15-03/139r4
Submission
Out-of-band rejection filter
• Proposed: use elliptic filter with poles placed at known out-of-band interferers.
e.g. BP 3rd order with pole at 2.45GHz
July 2003
Didier Helal and Philippe Rouzet, STMSlide 96
doc.: IEEE 802.15-03/139r4
Submission
Comparison on different pulse shapes
0 2 4 6 8 10 12-190
-180
-170
-160
-150
-140
-130
-120
-110
-1003-7GHz 7 sub-bands
0 2 4 6 8 10 12-190
-180
-170
-160
-150
-140
-130
-120
-110
-100
3-7GHz 7 sub-bands3-7GHz gap@5GHz 5 sub-bands
Pulse P2 BW = 3.3-7.2GHz
At 110Mbps, CM4 or CM3, Link budget margin is TBD dB
BW = 3.3-4.9; 6.1-7.2GHz
At 110Mbps, CM4 or CM3, Link budget margin is TBD dB
Monopulse Adaptive band PPM-UWB system easily accommodates regulation impact on pulse shape