IEEE 802.15 <subject>

1
Project IEEE P802.15 Working Group for Wireless
Personal Area Networks (WPANs) Submission Title
TG3a-Wisair-CFP-Presentation Date Submitted
3 March, 2003 Source Gadi Shor Company
Wisair Address 24 Raoul Wallenberg st. Ramat
Hachayal, Tel-Aviv, ISRAEL Voice
972-3-7676605 FAX [phone], E-Mail
gadi.shor_at_wisair.com Re 802.15.3a Call for
proposal Abstract Wisairs presentation for
the P802.15.3a PHY standard Purpose Response
to WPAN-802.15.3a Call for Proposals 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
Wisairs Variable-Pulse-Rate Multi-BandPHY layer
Proposal for TG3a

• Gadi Shor, Yaron Knobel, David Yaish,
• Sorin Goldenberg, Amir Krause, Erez Wineberger,
  Rafi Zack,
• Benny Blumer, Zeev Rubin, David Meshulam, Amir
  Freund
• Wisair

3
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

4
Targets

• Proposal for high bit-rate Multi-Band PHY layer
  for 802.15.3 MAC
• Support applications with wireless transmission
  of Audio/Video and High-Rate data communication
• Allow cost effective, low power implementation on
  chip

5
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

6
Main Features

• Variable-Pulse-Rate Multi-band PHY
• Flexible (use 1-gt14 sub-bands out of 30)
• World-wide regulation
• Co-existence with current and future systems
• Interference mitigation
• Scalable (Variable pulse repetition frequency)
• 20 to 1000 Mbps
• Reduced ADC sampling rate at lower Bit-rate
• Power consumption vs. Bit-rate trade off
• Support 802.15.3 MAC without modifications, only
  enhancements
• Support all selection criteria

7
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

8
Variable-Pulse-Rate Multi-Band PHY layer

• Sub-bands frequency plan
• Pulse shape
• Operation modes
• Variable-Pulse-Rate time-frequency interleaving
  sequences

9
Frequency Plan Consideration Points

• Consideration points
• FCC mask
• In band mask 3.1-10.6 GHz
• Indoor FCC mask require 10db attenuation at
  3.1GHz rejection
• Outdoor FCC mask require 20db attenuation at
  3.1GHz rejection
• 802.11a Frequency range
• US Canada 5.15 - 5.350GHz 5.725 - 5.825GHz
• Japan 4.9-5GHz ,5.15 - 5.25GHz
• Europe 5.15 - 5.35GHz 5.47 - 5.725GHz

10
Multi-Band Frequency-Plan

• Sub-bands are spaced 470 MHz apart
• For flexible co-existence and simple
  implementation
• Each sub band is generated by a pulse with 10 dB
  bandwidth of 520 MHz
• Supports FCC requirements

11
Two overlapping frequency groups (A, B)

• A Second group overlap the first group 235 MHz
  aside
• enhance system flexibility with respect to
  co-existence, interference mitigation and
  multiple access

12
Upper and Lower Sub-Band Sets

• Each group is divided into lower (sub-bands 1-8)
  and upper (sub-bands 9-15) sets
• Only 7 sub-bands are used in the lower set
• One sub-band can be avoided for co-existence
• The upper set is used in parallel to the lower
  set to increase the bit-rate
• First generation support lower set
• Next generation devices has backward compatibility

13
Signal spectrum Group A - Lower Set(ADS
Simulation)

• The sub-bands are divided into a lower set
  (lower 8 sub-bands) and an upper set (higher 7
  sub-bands)

14
Co-existence

• Center frequencies selected to allow elimination
  of one sub-band per region
• Only 7 sub-bands are used in the lower set
  according to the region

15
Co-existence

• Only 7 sub-bands out of 8 are used in the lower
  set according to the region

16
Co-existence (US)

• US Co existence with 802.11a
• avoid one of the Sub Channels 4a,5a,5b,6b

17
Co-existence (US)

• Example Avoid sub band 6b

18
Co-existence (Europe)

• Europe Co existence with 802.11a
• avoid one of the Sub Channels 4a,5a,5b,6b

19
Co-existence (Europe)

• Example Avoid sub band 5a

20
Co-existence (Japan)

• Japan Co existence with 802.11a
• avoid one of the Sub Channels 4a,4b

21
Co-existence (Japan)

• Example Avoid sub band 4a

22
Variable-Pulse-Rate Multi-BandModulation and
Coding Scheme

• The waveform is generated by time interleaving of
  pulses from different frequency sub-bands
• Modulation schemes QPSK and BPSK
• Coding Schemes Viterbi K7, Rate ½, ¾
• Three pulse repetition intervals supported to
  allow
• Reduced ADC sampling rate for improved power
  consumption
• Improved multiple access
• Improved ISI mitigation
• Energy collection

23
Variable-Pulse-Rate Multi-Band

• Pulse repetition interval per sub-band is longer
  than channel response
• 28 nSec 7 pulses 3.9 nSec each with 250 Mpps
• 56 nSec 7 pulses 3.9 nSec each with 125 Mpps
• 84 nSec 7 pulses 3.9 nSec each with 83.3 Mpps
• Reduce sampling rate for reduced bit rates

24
125 Mpps signal example(ADS simulation)

• Any number of sub-bands (Nlt7) can be used
• Unused sub-bands are not transmitted
• Example shows 4 sub-bands in use

25
Multi-band signal generation

• Above 500 Mbps the upper band optional section
  (Gray section) may be used to allow up to 1000
  Mbps

26
Pulse Shape
Pulse shape defines the envelope of the pulse
27
Operation Modes (7 bands example)
Mode Modulation Coding Rate Pulse Rate Mpulse/sec Sub- Band PRI nsec Data Rate Mbs -7 bands example
1 QPSK 1 250 28 500
2 QPSK ¾ 250 28 375
3 QPSK ½ 250 28 250
4 QPSK ¾ 125 56 187.5
5 QPSK ½ 125 56 125
6 QPSK ½ 83.33 84 83.3
7 BPSK ¾ 83.33 84 62.5
8 BPSK Repetition code x bands 125 56 17.86
28
Bit rates vs. Number of sub-bands

• In each operation mode different number of
  sub-bands can be used
• The table shows Bit-Rates for different number
  of sub-bands under different operation modes
• Mode 5 with 7 sub-bands supports 125Mbps (Meets
  IEEE 110Mpbs requirement)
• Mode 3 with 7 sub-bands supports 250Mbps (Meets
  IEEE 200Mpbs requirement)
• Mode 1 with 7 sub-bands supports 500Mbps for
  scalability
• Mode 8 is used for the beacon, same information
  is transmitted over all sub-bands

29
Time-Frequency interleaving sequences

• Each piconet uses a different time-frequency
  interleaving sequence of length 7
• The same sequence is used for the upper
  frequency set (in parallel to the lower set )
• The set is used according to the sequence, the
  mode of operation and the number of sub-bands to
  be used

30
Collision Example S1 and S2

• Only one collision for every possible time offset

31
Variable-rate Time-Frequency interleaving
sequences

• Example for 7 sub-bands using S2 in the different
  operation modes 250, 125 and 83.3 Mpps

• Preserve time-frequency sequences collision
  properties for all modes
• Reduce multi-path effect on collision between
  Piconets
• Improve multi-path mitigation and enable energy
  collection

32
Variable Rate Time Frequency interleaving
sequences

• Example for 4 sub-bands using S2 in the different
  operation modes 250, 125 and 83.3 Mpps

• For lower number of sub-bands only relevant
  sub-bands are used
• Preserve the collision properties for any number
  of sub-bands

33
Multiple-Access

• Use of different time-frequency interleaving
  sequences in different Piconets to reduce
  collisions
• Reduce number of channels in use, to reduce
  collisions (FDM alternative when link budget good
  enough)
• Reduce pulse repetition frequency to reduce
  multi-path effects on Multiple access

34
Preamble

• Use CAZAC sequences over all sub-bands in use
  (Similar to mode 8)
• Approximately 10 Micro Seconds
• Achieve False-Alarm and Miss-Detect requirements
  under multi-path and multiple access interference
• Use color code to improve Piconet identification

35
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

36
Block Diagram Analog Section
37
Block Diagram Digital Section
Coded bits are being spread over the different
sub-bands
38
Technical Feasibility

• Establish wireless link using prototype
• 15Mbps _at_ 30 meters
• 30Mbps _at_ 25 meters
• 60Mbps _at_ 18 meters

39
Size
The size was calculated using SiGe process with
fT60GHz for the analog blocks and 0.13 CMOS
process for the digital blocks. The size includes
pads overhead.
40
Main Modes Bit Rates versus Power Consumption
and Link Margin
Mode Bit Rate with 7 sub-bands Link Budget Margin RF- Tx Power mW PHY Tx Power mW (0.13u) Total PHY Tx Power mw RF- Rx Power mW PHY Rx Power mW (0.13u) Total PHY Rx Power mW
5 125 4.84 dB _at_10m 65 20 85 100 30 130
3 250 9.79 dB _at_4m 95 30 125 140 40 180
Less than 1 mWatt per 1 Mbps
41
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

42
PHY Mapping on current 802.15.3 MAC

• The proposed PHY can be used with the current MAC
  without modifications
• Piconet channel is represented by a
  TimeFrequency interleaving seed sequence
• Each Piconet choose a different seed sequence
  (channel)
• Devices in the same piconet use the same seed
  sequence (channel)
• Channel Sequence
• The Piconet beacon frames are transmitted over
  all sub-bands
• This is done transparently to the MAC (using PHY
  mode 8)

43
Location Awareness

• Special command frame that support Time Advanced
  measurement between two Piconet devices
• Two devices exchange two messages
• Dev A to Dev B Send time A
• Dev B to Dev A Time Diff A(Receive Time A - Send
  Time A ) and Send Time B
• Dev A calculates
• Time Diff B (Receive Time B - Send Time B )
• Time between Dev A to Dev B ½ (Diff A Diff B)

44
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

45
Link Budget (7 sub-bands)
Positive link margins for main modes
46
Performance under multi-path conditionWithout
Equalizer

• Bit rate 125 Mbps (Mode 5)
• Number of bands 7
• Simulating 400 channel realizations
• For each point either 250 packets or 21 packet
  errors were used
• Results represent statistics of 5 Gbits
• Note Shadow parameter in channel model is very
  dominant

47
125 Mbps LOS 0-4 (CM1)(with Shadow)
48
125 Mbps LOS 0-4 (CM1)(No Shadow)
49
125 Mbps LOS 0-4 (CM1) Statistics(With Shadow)
50
125 Mbps CM1-4 Statistics(90 Average PER with
Shadow)
51
Performance under multi-path condition(Distance
for 8 Average PER Best 90)

• Modulation scheme copes with multi-path condition
  without any equalization

52
Co-Existence with 802.11A and 802.11B Required
attenuation below FCC limits
802.11a requires attenuation above FCC limits
53
Co-Existence (ADS simulation)

• System co-exist with 802.11a and 802.11b

54
Interference
55
802.11a Interference 100 cm(ADS Simulation)
Wanted signal bit energy _at_RED
Intereferer signal bit energy _at_Blue
EBIT_INT
C/I dB _at_Interefer 5.15GHz, -30dBm

• Seven sub-bands with C/I better than 10 dB after
  eliminating one sub-band (F4A)

56
802.11a Interference 30 cm(ADS Simulation)
Wanted signal bit energy _at_RED
Intereferer signal bit energy _at_Blue
EBIT_INT
C/I dB _at_Interefer 5.15GHz, -20dBm

• Five sub-bands with C/I better than 10 dB after
  eliminating one sub-band (F4A)

57
Performance with 802.11a under AWGN

• ISR55 dB in AWGN (including F.E. rejection)
• Allows 30 cm separation

58
Performance with 802.11a under CM1

• ISR50 dB in CM1 (including F.E. rejection)
• Allows 50 cm separation

59
Performance Under Multiple-Access

• Desired piconet
• LOS 0-4 (CM149)
• Interfering piconet
• LOS 0-4 (CM11)
• Worst case shift between piconets

• ISR12.3 dB for 8 per
• Allows R(Ref)/R(Int) 4
• Example R(Ref)10 meters allows R(Int)2.5
  meters
• ISR can be improved by reducing number of
  sub-bands or increasing PRI

60
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

61
Self Evaluation General Solution Criteria
CRITERIA Evaluation
Unit Manufacturing Cost (UMC)
Signal Robustness Interference And Susceptibility
Coexistence
Technical Feasibility Manufacturability
Time To Market
Regulatory Impact
Scalability
Location Awareness 0
62
Self Evaluation PHY Protocol Criteria
CRITERIA Evaluation
Size and Form Factor
Payload Bit Rate
Packet Overhead
PHY-SAP Throughput
Simultaneously Operation Piconets
Signal Acquisition
System Performance
Link Budget
Sensitivity
Power Management Modes
Power Consumption
Antenna Practicality
63
Self Evaluation MAC Protocol Enhancement
Criteria
CRITERIA Evaluation
MAC Enhancement and Modifications
Meets all selection criteria
64
Contents

• Targets
• Main Features
• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance
• Self Evaluation
• Conclusions

65
Conclusions

• Multi-Band scheme
• 30 Sub-bands allows flexible system
• meets all selection criteria
• Variable-Pulse-Rate
• Low power for lower bit rates
• Reduces ISI problem without equalizer
• Improves multiple access
• Technology demonstrated on prototype

66
802.15.3a Early Merge Work
Wisair will be cooperating with

• Intel
• Time Domain
• Discrete Time
• General Atomics
• Philips
• FOCUS Enhancements
• Samsung

• Objectives
• Best Technical Solution
• ONE Solution
• Excellent Business Terms
• Fast Time To Market

We encourage participation by any party who can
help us reach our goals.
67
Backup Slides
68
Contents

• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance

69
Contents

• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance

70
Contents

• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance

71
MAC Enhancements (1)

• UWB based WPAN system should support a higher bit
  rate (e.g. 110Mbps, 200Mbps)
• Current MAC Throughput is degraded in high bit
  rate
• Support a bigger packet length
• Bigger packets may be needed for high data rate
  applications
• Improve the throughput
• For both small and large packet sizes
• For retransmission mode
• Support Multiband channel assignment
• Decide on usable sub bands
• Select the time frequency interleaving sequence

72
MAC Enhancements (2) PHY SAP Data Throughput
Calculation
Payload Throughput PHY-SAP N x Payload_bits
/ T_PA_INITIALT_SIFS (N-1) x
(T_PA_CONTT_MIFS) N x (Payload_bits/R_PayT_MA
CHDR T_PHYHDRT_HCST_FCS)
73
MAC Enhancements (3) IEEE802.15.3 PHY-SAP Data
Throughput
N 5 Frames T_PA_INITIAL 15uSec T_PA_CONT
15uSec
MACHDR10 Octets PHYHDR2 Octets
T_SIFS 10uSec T_MIFS 2uSec
HCS2 Octets FCS 4 Octets
74
MAC Enhancements (4) IEEE802.15.3 PHY-SAP Data
Throughput in High Bit Rates
N 5 Frames T_PA_INITIAL 15uSec T_PA_CONT
15uSec
MACHDR10 Octets PHYHDR2 Octets
T_SIFS 10uSec T_MIFS 2uSec
HCS2 Octets FCS 4 Octets
75
MAC Enhancements(5) Proposed MAC Performance
PHY-SAP Data Throughput in High Bit Rates
N 5 Frames T_PA_INITIAL 15uSec T_PA_CONT
15uSec
MACHDR10 Octets PHYHDR2 Octets
T_SIFS 10uSec T_MIFS 2uSec
HCS2 Octets FCS 4 Octets
76
MAC Enhancements (6) Proposed MAC Frame Structure

• Allow larger MAC frame body size (e.g. 4096
  Octets
• Frame body consists of N Sub-frames
• Sub-frame consists of Data block unit and CRC
• Data block unit is limited by a maximum number of
  octets (e.g. 512 octets)

77
MAC Enhancements (7)

• The proposed UWB PHY structure is based on
  multi-band UWB system
• MAC logical channel is mapped to several
  frequency bands
• Some bands might be interfered (useless) by other
  existing systems (I.e IEEE802.11a 5GHz)
• MAC should be able to drive a Bands Quality
  Assessment (BQA) that determines whether a
  specific band is usable or not
• The Piconet Coordinator (PNC) should be able to
  distribute the usable bands to all its associated
  devices

78
MAC Enhancements (8)

• Provide BQA time slot at the Supper-frame
• Useful information is distributed as Information
  Element (IE) over PNC Beacon
• Beacon will transmitted over the whole frequency
  bands

79
MAC Enhancements (9)
80
Contents

• Physical layer
• Implementation and Feasibility
• MAC enhancements
• Performance

81
125 Mbps CM1 channels
82
125 Mbps CM1 (No Shadow)
83
125 Mbps CM1 Statistics
84
125 Mbps CM2 channels
85
125 Mbps CM2 (No Shadow)
86
125 Mbps CM2 Statistics
87
125 Mbps CM3 channels
88
125 Mbps CM3 (No Shadow)
89
125 Mbps CM3 Statistics
90
125 Mbps CM4 channels
91
125 Mbps CM4 (No Shadow)
92
125 Mbps CM4 Statistics