doc.: ieee 802.15-03/267r6 submission september 2003 a. batra, texas instruments et al.slide 1...
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September 2003
A. Batra, Texas Instruments et al.Slide 1
doc.: IEEE 802.15-03/267r6
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: [Multi-band OFDM Physical Layer Proposal]Date Submitted: [17 September, 2003]Source: [Presenter: Anuj Batra] Company [Texas Instruments] [see page 2,3 for the complete list of company names and authors]
Address [12500 TI Blvd, MS 8649, Dallas, TX 75243]Voice:[214-480-4220], FAX: [972-761-6966], E-Mail:[[email protected]]
Re: [This submission is in response to the IEEE P802.15 Alternate PHY Call for Proposal (doc. 02/372r8) that was issued on January 17, 2003.]
Abstract: [This document describes the Multi-band OFDM proposal for IEEE 802.15 TG3a.]
Purpose: [For discussion by IEEE 802.15 TG3a.]
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.
September 2003
A. Batra, Texas Instruments et al.Slide 2
doc.: IEEE 802.15-03/267r6
Submission
This contribution is a technical merger between*:Texas Instrument [03/141]: Batra
\
andfemto Devices [03/101]: CheahFOCUS Enhancements [03/103]: BoehlkeGeneral Atomics [03/105]: EllisInstitute for Infocomm Research [03/107]: ChinIntel [03/109]: BrabenacMitsubishi Electric [03/111]: MolischPanasonic [03/121]: MoPhilips [03/125]: KerrySamsung Advanced Institute of Technology [03/135]: KwonSamsung Electronics [03/133]: ParkSONY [03/137]: FujitaStaccato Communications [03/099]: AielloSTMicroelectronics [03/139]: RobertsTime Domain [03/143]: KellyUniversity of Minnesota [03/147]: TewfikWisair [03/151]: Shor
* For a complete list of authors, please see page 3.
September 2003
A. Batra, Texas Instruments et al.Slide 3
doc.: IEEE 802.15-03/267r6
Submission
Authorsfemto Devices: J. CheahFOCUS Enhancements: K. Boehlke General Atomics: J. Ellis, N. Askar, S. Lin, D. Furuno, D. Peters, G. Rogerson, M. WalkerInstitute for Infocomm Research: F. Chin, Madhukumar, X. Peng, SivanandIntel: J. Foerster, V. Somayazulu, S. Roy, E. Green, K. Tinsley, C. Brabenac, D. Leeper, M. HoMitsubishi Electric: A. F. Molisch, Y.-P. Nakache, P. Orlik, J. ZhangPanasonic: S. MoPhilips: C. Razzell, D. Birru, B. Redman-White, S. KerrySamsung Advanced Institute of Technology: D. H. Kwon, Y. S. KimSamsung Electronics: M. ParkSONY: E. Fujita, K. Watanabe, K. Tanaka, M. Suzuki, S. Saito, J. Iwasaki, B. HuangStaccato Communications: R. Aiello, T. Larsson, D. Meacham, L. Mucke, N. Kumar STMicroelectronics: D. Hélal, P. Rouzet, R. Cattenoz, C. Cattaneo, L. Rouault, N. Rinaldi,, L.
Blazevic, C. Devaucelle, L. Smaïni, S. Chaillou Texas Instruments: A. Batra, J. Balakrishnan, A. Dabak, R. Gharpurey, J. Lin, P. Fontaine,
J.-M. Ho, S. Lee, M. Frechette, S. March, H. YamaguchiTime Domain: J. Kelly, M. PendergrassUniversity of Minnesota: A. H. Tewfik, E. SaberiniaWisair: G. Shor, Y. Knobel, D. Yaish, S. Goldenberg, A. Krause, E. Wineberger, R. Zack, B.
Blumer, Z. Rubin, D. Meshulam, A. Freund
September 2003
A. Batra, Texas Instruments et al.Slide 4
doc.: IEEE 802.15-03/267r6
Submission
In addition, the following individuals/companies support this proposal:
Fujitsu Microelectronics America, Inc: A. Agrawal Hewlett Packard: M. FidlerInfineon: Y. RashiNEC Electronics: T. SaitoSVC Wireless: A. YangTDK: P. CarsonTRDA: M. TanahashiUWB Wireless: R. Caiming QuiWisme: N. Y. LeeMicrosoft: A. HassanJaalaa: A. AnandakumarTzero: O. Unsal
September 2003
A. Batra, Texas Instruments et al.Slide 5
doc.: IEEE 802.15-03/267r6
Submission
Overview of OFDM
OFDM was invented more than 40 years ago.
OFDM has been adopted for several technologies: Asymmetric Digital Subscriber Line (ADSL) services. IEEE 802.11a/g. IEEE 802.16a. Digital Audio Broadcast (DAB). Digital Terrestrial Television Broadcast: DVD in Europe, ISDB in Japan
OFDM is also being considered for 4G, IEEE 802.11n, IEEE 802.16, and IEEE 802.20.
September 2003
A. Batra, Texas Instruments et al.Slide 6
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Submission
Strengths of OFDM
OFDM is spectrally efficient. IFFT/FFT operation ensures that sub-carriers do not interfere with each
other.
OFDM has an inherent robustness against narrowband interference. Narrowband interference will affect at most a couple of tones. Information from the affected tones can be erased and recovered via the
forward error correction (FEC) codes.
OFDM has excellent robustness in multi-path environments. Cyclic prefix preserves orthogonality between sub-carriers. Cyclic prefix allows the receiver to capture multi-path energy more
efficiently.
September 2003
A. Batra, Texas Instruments et al.Slide 7
doc.: IEEE 802.15-03/267r6
Submission
Details of the Multi-band OFDM System
*More details about the Multi-band OFDM system can be found in the latest version of 03/268.
September 2003
A. Batra, Texas Instruments et al.Slide 8
doc.: IEEE 802.15-03/267r6
Submission
Overview of Multi-band OFDM
Basic idea: divide spectrum into several 528 MHz bands.
Information is transmitted using OFDM modulation on each band. OFDM carriers are efficiently generated using an 128-point IFFT/FFT. Internal precision is reduced by limiting the constellation size to QPSK.
Information bits are interleaved across all bands to exploit frequency diversity and provide robustness against multi-path and interference.
60.6 ns prefix provides robustness against multi-path even in the worst channel environments.
9.5 ns guard interval provides sufficient time for switching between bands.
September 2003
A. Batra, Texas Instruments et al.Slide 9
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDM: TX Architecture
Block diagram of an example TX architecture:
Architecture is similar to that of a conventional and proven OFDM system. Can leverage existing OFDM solutions for the development of the Multi-band OFDM physical layer.
DACScramblerConvolutional
EncoderPuncturer
BitInterleaver
ConstellationMapping
IFFTInsert Pilots
Add Prefix/GI
Time-Frequency Code
exp(j2fct)
InputData
September 2003
A. Batra, Texas Instruments et al.Slide 10
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDM System Parameters
System parameters for mandatory and optional data rates:
Info. Data Rate 55 Mbps* 80 Mbps** 110 Mbps* 160 Mbps** 200 Mbps* 320 Mbps** 480 Mbps**
Modulation/Constellation OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK OFDM/QPSK
FFT Size 128 128 128 128 128 128 128
Coding Rate (K=7) R = 11/32 R = 1/2 R = 11/32 R = 1/2 R = 5/8 R = 1/2 R = 3/4
Frequency-domain Spreading Yes Yes No No No No No
Time-domain Spreading Yes Yes Yes Yes Yes No No
Data Tones 100 100 100 100 100 100 100
Zero-padded Prefix 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns
Guard Interval 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns 9.5 ns
Symbol Length 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns 312.5 ns
Channel Bit Rate 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps 640 Mbps
Multi-path Tolerance 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns 60.6 ns
* Mandatory information data rate, ** Optional information data rate
September 2003
A. Batra, Texas Instruments et al.Slide 11
doc.: IEEE 802.15-03/267r6
Submission
Frequency-Domain and Time-Domain Spreading
Frequency-domain spreading: Spreading is achieved by choosing conjugate symmetric inputs for
the input to the IFFT. Exploits frequency diversity and helps reduce the transmitter
complexity/power consumption.
Time-domain spreading: Spreading is achieved in the time-domain by repeating the same
information in an OFDM symbol on two different sub-bands. Exploits frequency diversity as well as enhances SOP performance.
September 2003
A. Batra, Texas Instruments et al.Slide 12
doc.: IEEE 802.15-03/267r6
Submission
Simplified TX Analog Section
For rates up to 80 Mb/s, the input to the IFFT is forced to be conjugate symmetric (for spreading gains 2). Output of the IFFT is REAL.
The analog section of TX can be simplified when the input is real: Need to only implement the “I” portion of DAC and mixer. Only requires half the analog die size of a complete “I/Q” transmitter.
For rates > 80 Mb/s, need to implement full “I/Q” transmitter.
DACScramblerConvolutional
EncoderPuncturer
BitInterleaver
ConstellationMapping
IFFTInsert Pilots
Add CP & GI
Time Frequency Code
cos(2fct)
InputData
September 2003
A. Batra, Texas Instruments et al.Slide 13
doc.: IEEE 802.15-03/267r6
Submission
More Details on the OFDM Parameters
128 total tones: 100 data tones used to transmit information (constellation: QPSK) 12 pilots tones used for carrier and phase tracking 10 guard tones (used to be known as dummy tones) 6 NULL tones
Exact use of guard tones is left to implementer – adds a level of flexibility in the standard.
Advantages of using guard tones: Can relax the analog transmit and receive filters. Helps to relax filter specifications for adjacent channel rejection. Can be used to help reduce peak-to-average power ratio (PARP). Could be used to transmit proprietary information (data/signaling).
If data is mapped onto the guard tones, then this scheme is analogous to the concept of Excess Bandwidth as used in Single-carrier Systems. Received signal in guard tones can be combined appropriately with the remaining
information data tones to improve performance.
September 2003
A. Batra, Texas Instruments et al.Slide 14
doc.: IEEE 802.15-03/267r6
Submission
Zero-padded Prefix (1)
Ripple in the transmitted spectrum can be eliminated by using a zero-padded prefix.
Using a zero-padded (ZP) prefix instead of a cyclic prefix is a well-known and well-analyzed technique.
Almost no ripple in PSD.
September 2003
A. Batra, Texas Instruments et al.Slide 15
doc.: IEEE 802.15-03/267r6
Submission
Zero-Padded Prefix (2) A Zero-Padded Multi-band OFDM has the same multi-path robustness as a system
that uses a cyclic prefix (60.6 ns of protection).
The receiver architecture for a zero-padded multi-band OFDM system requires ONLY a minor modification (less than < 200 gates).
Added flexibility to implementer: multi-path robustness can be dynamically controlled at the receiver, from 1.9 ns up to 60.6 ns.
Channel+
OFDM Signal
IFFTOutput
CP
`
+
FFT Input
Same
WithCP
Channel `
+
FFT Input
Copy
WithZP +
OFDM Signal
IFFTOutput
ZP
September 2003
A. Batra, Texas Instruments et al.Slide 16
doc.: IEEE 802.15-03/267r6
Submission
Band Plan (1)
Group the 528 MHz bands into 4 distinct groups.
Group A: Intended for 1st generation devices (3.1 – 4.9 GHz). Group B: Reserved for future use (4.9 – 6.0 GHz). Group C: Intended for devices with improved SOP performance (6.0 – 8.1 GHz). Group D: Reserved for future use (8.1 – 10.6 GHz).
f3432MHz
3960MHz
4488MHz
5016MHz
5808MHz
6336MHz
6864MHz
7392MHz
7920MHz
8448MHz
8976MHz
9504MHz
10032MHz
Band#1
Band#2
Band#3
Band#4
Band#5
Band#6
Band#7
Band#8
Band#9
Band#10
Band#11
Band#12
Band#13
GROUP A GROUP B GROUP C GROUP D
September 2003
A. Batra, Texas Instruments et al.Slide 17
doc.: IEEE 802.15-03/267r6
Submission
Band Plan (2)
The relationship between the center frequency fc and the band number nb is:
BAND_ID (nb) LowerFrequency
(fl)
CenterFrequency
(fc)
HigherFrequency
(fh)
BAND_ID (nb) LowerFrequency
(fl)
Center
Frequency(fc)
HigherFrequency
(fh)
1 3168 MHz 3432 MHz 3696 MHz 8 7128 MHz 7392 MHz 7656 MHz
2 3696 MHz 3960 MHz 4224 MHz 9 7656 MHz 7920 MHz 8184 MHz
3 4224 MHz 4488 MHz 4752 MHz 10 8184 MHz 8448 MHz 8712 MHz
4 4752 MHz 5016 MHz 5280 MHz 11 8712 MHz 8976 MHz 9240 MHz
5 5544 MHz 5808 MHz 6072 MHz 12 9240 MHz 9504 MHz 9768 MHz
6 6072 MHz 6336 MHz 6600 MHz 13 9768 MHz 10032 MHz 10296 MHz
7 6600 MHz 6864 MHz 7128 MHz
13,,55283168
4,,15282904)(
bb
bbbc nn
nnnf
September 2003
A. Batra, Texas Instruments et al.Slide 18
doc.: IEEE 802.15-03/267r6
Submission
Multi-mode Multi-band OFDM Devices (1)
Having multiple groups of bands enables multiple modes of operations for multi-band OFDM devices.
Different modes for multi-band OFDM devices are:
Future expansion into groups B and D will enable an increase in the number of modes.
Mode Frequency of Operation Number of Bands Mandatory / Optional
1 Bands 1–3 (A) 3 Mandatory
2 Bands 1–3, 6–9 (A,C) 7 Optional
September 2003
A. Batra, Texas Instruments et al.Slide 19
doc.: IEEE 802.15-03/267r6
Submission
Multi-mode Multi-band OFDM Devices (2)
Frequency of operation for a Mode 1 device:
Frequency of operation for a Mode 2 device:
f3432MHz
3960MHz
4488MHz
Band#1
Band#2
Band#3
f3432MHz
3960MHz
4488MHz
6336MHz
6864MHz
7392MHz
7920MHz
Band#1
Band#2
Band#3
Band#6
Band#7
Band#8
Band#9
September 2003
A. Batra, Texas Instruments et al.Slide 20
doc.: IEEE 802.15-03/267r6
Submission
Frequency Synthesis (1)
Example: frequency synthesis for Mode 1 (3-band) device:
A single PLL can also be used to generate the center frequencies for a Mode 2 (7-band) device.
528 MHz
PLL
/ 8 / 2
SSB
4224 MHz
264 MHz
SSB
Select
DesiredCenter
Frequency
SamplingClock
792 MHz
September 2003
A. Batra, Texas Instruments et al.Slide 21
doc.: IEEE 802.15-03/267r6
Submission
Frequency Synthesis (2) Circuit-level simulation of frequency synthesis:
Nominal switching time = ~2 ns.
Need to use a slightly larger switching time to allow for process and temperature variations.
Switching Time = ~2 nsSwitching Time = ~2 ns
September 2003
A. Batra, Texas Instruments et al.Slide 22
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDM: PLCP Frame Format
PLCP frame format:
Rates supported: 55, 80, 110, 160, 200, 320, 480 Mb/s. Support for 55, 110, and 200 Mb/s is mandatory.
Mode 1 (3-band): Preamble + Header = 11.875 s. Burst preamble + Header = 7.1875 s.
Mode 2 (7-band): Preamble + Header + Band Extension = 15.625 s. Burst preamble + Header + Band Extension = 10.9375 s.
Header is sent at an information data rate of 55 Mb/s using Mode 1. Maximum frame payload supported is 4095 bytes.
PLCP PreamblePHY
HeaderMAC
HeaderHCS
TailBits
TailBits
PadBits
Frame PayloadVariable Length: 0 4095 bytes
PadBits
TailBits
FCSOptional
BandExtension
55 Mb/sPLCP Header 55, 80, 110, 160, 200, 320, 480 Mb/s
RATE4 bits
LENGTH12 bits
Scrambler Init2 bits
Reserved1 bit
Band Extension3 bits
Reserved1 bit
Reserved1 bit
Reserved1 bit
Reserved3 bit
September 2003
A. Batra, Texas Instruments et al.Slide 23
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Submission
More Details on the PHY Header
PHY Header:
Band Extension (3 bit field): Indicates the mode of transmission for the payload (Mode 1 or Mode 2).
Rate (4 bit field): Indicates the rate of transmission for the payload. Rate field also specifies the coding rate, puncturing pattern, and spreading
technique.
Length (12 bit field): Indicates the number of bytes in the payload (excludes the FEC).
Scrambler (2 bit field): Conveys information about the scrambler state.
RATE4 bits
LENGTH12 bits
Scrambler Init2 bits
Reserved1 bit
Band Extension3 bits
Reserved1 bit
Reserved1 bit
Reserved1 bit
Reserved3 bit
September 2003
A. Batra, Texas Instruments et al.Slide 24
doc.: IEEE 802.15-03/267r6
Submission
Multiple Access
Multiple piconet performance is governed by the bandwidth expansion factor.
Bandwidth expansion can be achieved using any of the following techniques or combination of techniques: Spreading, Time-frequency interleaving, Coding Ex: Multi-band OFDM obtains its BW expansion by using all 3 techniques.
Time Frequency Codes:
Channel Number
PreamblePattern
Mode 1 DEV: 3-band
Length 6 TFC
Mode 1 DEV: 7-band
Length 7 TFC
1 1 1 2 3 1 2 3 1 2 3 4 5 6 7
2 2 1 3 2 1 3 2 1 7 6 5 4 3 2
3 3 1 1 2 2 3 3 1 4 7 3 6 2 5
4 4 1 1 3 3 2 2 1 3 5 7 2 4 6
September 2003
A. Batra, Texas Instruments et al.Slide 25
doc.: IEEE 802.15-03/267r6
Submission
PLCP Preamble (1)
Multi-band OFDM preamble is composed of 3 sections: Packet sync sequence: used for packet detection. Frame sync sequence: used for boundary detection. Channel estimation sequence: used for channel estimation.
Packet and frame sync sequences are constructed from the same hierarchical sequence.
Correlators for hierarchical sequences can be implemented efficiently: Low gate count. Extremely low power consumption.
Preamble sequences are designed to be extremely robust.
September 2003
A. Batra, Texas Instruments et al.Slide 26
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Submission
PLCP Preamble (2)
In the multiple overlapping piconet case, it is desirable to use different hierarchical preambles for each of the piconets.
Basic idea: define 4 hierarchical preambles, with low cross-correlation values.
Preambles are generated by spreading a length 16 sequence by a length 8 sequence.
Sequence A(length 16)
Sequence B(length 8)
SpreaderSequence C(length 128)
Preamble Pattern Sequence A
1 1 1 1 1 -1 -1 1 1 -1 -1 1 -1 1 -1 1 1
2 1 -1 -1 -1 -1 -1 1 -1 1 -1 -1 1 1 -1 -1 1
3 1 1 -1 -1 -1 1 -1 -1 -1 1 -1 -1 1 -1 1 1
4 1 -1 -1 1 -1 1 -1 -1 1 1 -1 -1 -1 -1 -1 1
Preamble Pattern Sequence B
1 1 -1 -1 -1 1 1 -1 1
2 1 -1 1 1 -1 -1 -1 1
3 1 1 -1 1 1 -1 -1 -1
4 1 1 1 -1 -1 1 -1 -1
September 2003
A. Batra, Texas Instruments et al.Slide 27
doc.: IEEE 802.15-03/267r6
Submission
Link Budget and Receiver Sensitivity
Assumption: Mode 1 DEV (3-band), AWGN, and 0 dBi gain at TX/RX antennas.
Parameter Value Value Value
Information Data Rate 110 Mb/s 200 Mb/s 480 Mb/s
Average TX Power -10.3 dBm -10.3 dBm -10.3 dBm
Total Path Loss 64.2 dB
(@ 10 meters)
56.2 dB
(@ 4 meters)
50.2 dB
(@ 2 meters)
Average RX Power -74.5 dBm -66.5 dBm -60.5 dBm
Noise Power Per Bit -93.6 dBm -91.0 dBm -87.2 dBm
CMOS RX Noise Figure 6.6 dB 6.6 dB 6.6 dB
Total Noise Power -87.0 dBm -84.4 dBm -80.6 dBm
Required Eb/N0 4.0 dB 4.7 dB 4.9 dB
Implementation Loss 2.5 dB 2.5 dB 3.0 dB
Link Margin 6.0 dB 10.7 dB 12.2 dB
RX Sensitivity Level -80.5 dBm -77.2 dBm -72.7 dB
September 2003
A. Batra, Texas Instruments et al.Slide 28
doc.: IEEE 802.15-03/267r6
Submission
Link Budget and Receiver Sensitivity
Assumption: Mode 2 DEV (7-band), AWGN, and 0 dBi gain at TX/RX antennas.
Parameter Value Value Value
Information Data Rate 110 Mb/s 200 Mb/s 480 Mb/s
Average TX Power -6.6 dBm -6.6 dBm -6.6 dBm
Total Path Loss 66.6 dB
(@ 10 meters)
58.6 dB
(@ 4 meters)
52.6 dB
(@ 2 meters)
Average RX Power -73.2 dBm -65.2 dBm -59.2 dBm
Noise Power Per Bit -93.6 dBm -91.0 dBm -87.2 dBm
CMOS RX Noise Figure 8.6 dB 8.6 dB 8.6 dB
Total Noise Power -85.0 dBm -82.4 dBm -78.6 dBm
Required Eb/N0 4.0 dB 4.7 dB 4.9 dB
Implementation Loss 2.5 dB 2.5 dB 3.0 dB
Link Margin 5.3 dB 10.0 dB 11.5 dB
RX Sensitivity Level -78.5 dBm -75.2 dBm -70.7 dB
September 2003
A. Batra, Texas Instruments et al.Slide 29
doc.: IEEE 802.15-03/267r6
Submission
System Performance (Mode 1: 3-band)
The distance at which the Multi-band OFDM system can achieve a PER of 8% for a 90% link success probability is tabulated below:
* Includes losses due to front-end filtering, clipping at the DAC, ADC degradation, multi-path degradation, channel estimation, carrier tracking, packet acquisition, etc.
Range* AWGN CM1 CM2 CM3 CM4
110 Mbps 20.5 m 11.4 m 10.7 m 11.5 m 10.9 m
200 Mbps 14.1 m 6.9 m 6.3 m 6.8 m 4.7 m
480 Mbps 7.8 m 2.9 m 2.6 m N/A N/A
September 2003
A. Batra, Texas Instruments et al.Slide 30
doc.: IEEE 802.15-03/267r6
Submission
System Performance (Mode 2: 7-band)
The distance at which the Multi-band OFDM system can achieve a PER of 8% for a 90% link success probability is tabulated below:
* Includes losses due to front-end filtering, clipping at the DAC, ADC degradation, multi-path degradation, channel estimation, carrier tracking, packet acquisition, etc.
Range* AWGN CM1 CM2 CM3 CM4
110 Mbps 18.9 m 10.0 m 9.0 m 9.9 m 9.7 m
200 Mbps 13.0 m 6.4 m 5.7 m 6.4 m 4.2 m
480 Mbps 7.2 m 2.4 m 2.2 m N/A N/A
September 2003
A. Batra, Texas Instruments et al.Slide 31
doc.: IEEE 802.15-03/267r6
Submission
Simultaneously Operating Piconets (1)
Assumptions: Mode 1 DEV (3-band) operating at a data rate of 110 Mbps.
Simultaneously operating piconet performance as a function of the multipath channel environments:
Results incorporate SIR and erasure estimation at the receiver.
Channel Environment 1 piconet* 2 piconets** 3 piconets**
CM1 (dint/dref) 0.40 1.18 1.45
CM2 (dint/dref) 0.40 1.24 1.47
CM3 (dint/dref) 0.40 1.21 1.46
CM4 (dint/dref) 0.40 1.53 1.85
* Acquisition limited. ** Numbers based on July results. Currently running simulations to obtain updated numbers.
September 2003
A. Batra, Texas Instruments et al.Slide 32
doc.: IEEE 802.15-03/267r6
Submission
Simultaneously Operating Piconets (2)
Assumptions: Mode 2 DEV (7-band) operating at a data rate of 110 Mbps.
Simultaneously operating piconet performance as a function of the multipath channel environments:
Results incorporate SIR estimation at the receiver.
Channel Environment 1 piconet* 2 piconets** 3 piconets**
CM1 (dint/dref) 0.30 0.65 0.86
CM2 (dint/dref) 0.30 0.64 0.80
CM3 (dint/dref) 0.30 0.66 0.81
CM4 (dint/dref) 0.30 0.84 1.01
* Acquisition limited. ** Numbers based on July results. Currently running simulations to obtain updated numbers.
September 2003
A. Batra, Texas Instruments et al.Slide 33
doc.: IEEE 802.15-03/267r6
Submission
Simultaneously Operating Piconets (3)
Assumptions: Mode 2 DEV (7-band) operating at a data rate of 200 Mbps.
Simultaneously operating piconet performance as a function of the multipath channel environments:
Results incorporate SIR estimation at the receiver.
Channel Environment 1 piconet* 2 piconets** 3 piconets**
CM1 (dint/dref) 0.30 1.25 1.60
CM2 (dint/dref) 0.30 1.15 1.45
CM3 (dint/dref) 0.30 1.13 1.39
CM4 (dint/dref) 0.30 1.62 1.97
* Acquisition limited. ** Numbers based on July results. Currently running simulations to obtain updated numbers.
September 2003
A. Batra, Texas Instruments et al.Slide 34
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Submission
Signal Robustness/Coexistence
Assumption: Received signal is 6 dB above sensitivity.
Value listed below are the required distance or power level needed to obtain a PER 8% for a 1024 byte packet at 110 Mb/s and a Mode 1 DEV (3-band).
Coexistence with 802.11a/b and Bluetooth is straightforward because these bands can be completely avoided.
Interferer Value
IEEE 802.11b @ 2.4 GHz dint 0.2 meter
IEEE 802.11a @ 5.3 GHz dint 0.2 meter
Modulated interferer SIR -9.0 dB
Tone interferer SIR -7.9 dB
September 2003
A. Batra, Texas Instruments et al.Slide 35
doc.: IEEE 802.15-03/267r6
Submission
PHY-SAP Throughput
Assumptions: MPDU (MAC frame body + FCS) length is 1024 bytes. SIFS = 10 s. MIFS = 2 s.
Assumptions: MPDU (MAC frame body + FCS) length is 4024 bytes.
Number of frames Throughput @ 110 Mb/s Throughput @ 200 Mb/s Throughput @ 480 Mb/s
1 Mode 1: 84.8 Mb/sMode 2: 81.3 Mb/s
Mode 1: 129.8 Mb/sMode 2: 122.0 Mb/s
Mode 1: 209.7 Mb/sMode 2: 190.6 Mb/s
5 Mode 1: 94.8 Mb/sMode 2: 90.5 Mb/s
Mode 1: 155.6 Mb/s
Mode 2: 143.9 Mb/s
Mode 1: 286.4 Mb/s
Mode 2: 249.8 Mb/s
Number of frames Throughput @ 110 Mb/s Throughput @ 200 Mb/s Throughput @ 480 Mb/s
1 Mode 1: 102.2 Mb/s Mode 2: 101.0 Mb/s
Mode 1: 175.6 Mb/sMode 2: 172.1 Mb/s
Mode 1: 361.1 Mb/sMode 2: 346.5 Mb/s
5 Mode 1: 105.6 Mb/sMode 2: 104.3 Mb/s
Mode 1: 185.9 Mb/sMode 2: 182.0 Mb/s
Mode 1: 407.6 Mb/sMode 2: 389.1 Mb/s
September 2003
A. Batra, Texas Instruments et al.Slide 36
doc.: IEEE 802.15-03/267r6
Submission
Complexity (1)
Unit manufacturing cost (selected information): Process: CMOS 90 nm technology node in 2005. CMOS 90 nm production will be available from all major SC foundries by early
2004.
Die size for Mode 1 (3-band) device:
Die size for Mode 2 (7-band) device:
Complete Analog* Complete Digital
90 nm 3.0 mm2 1.9 mm2
130 nm 3.3 mm2 3.8 mm2
* Component area.
Complete Analog* Complete Digital
90 nm 3.2 mm2 1.9 mm2
130 nm 3.5 mm2 3.8 mm2
* Component area.
September 2003
A. Batra, Texas Instruments et al.Slide 37
doc.: IEEE 802.15-03/267r6
Submission
Complexity (2)
Active CMOS power consumption for Mode 1 (3-band) and Mode 2 (7-band) devices:
Block90 nm 130 nm
Mode1 Mode 2 Mode 1 Mode 2
TX (55 Mb/s) 85 mW 151 mW 104 mW 173 mW
TX (110, 200 Mb/s) 128 mW 212 mW 156 mW 240 mW
RX (55 Mb/s) 147 mW 201 mW 192 mW 258 mW
RX (110 Mb/s) 155 mW 209 mW 205 mW 271 mW
RX (200 Mb/s) 169 mW 223 mW 227 mW 293 mW
September 2003
A. Batra, Texas Instruments et al.Slide 38
doc.: IEEE 802.15-03/267r6
Submission
Complexity (3)
Manufacturability: Leveraging standard CMOS technology results in a straightforward
development effort. OFDM solutions are mature and have been demonstrated in ADSL and
802.11a/g solutions.
Scalability with process: Digital section complexity/power scales with improvements in technology
nodes (Moore’s Law). Analog section complexity/power scales slowly with technology node.
Time to market: 1H 2005.
Size: Solutions for PC card, compact flash, memory stick, SD memory in 2005.
September 2003
A. Batra, Texas Instruments et al.Slide 39
doc.: IEEE 802.15-03/267r6
Submission
Scalability of Multi-band OFDM
Data rate scaling: Data rates from 55 Mb/s to 480 Mb/s has been defined in the current
proposal.
Frequency scaling: Mode 1 (3-bands) and optional Mode 2 (7-band) devices. Guaranteed interoperability between different mode devices.
Power scaling: Implementers could always trade-off power consumption for range and
information data rate.
Complexity scaling: Digital section will scale with future CMOS process improvements. Implementers could always trade-off complexity for performance.
September 2003
A. Batra, Texas Instruments et al.Slide 40
doc.: IEEE 802.15-03/267r6
Submission
Comparison of OFDM Technologies Qualitative comparison between Multi-band OFDM and IEEE 802.11a OFDM:
CriteriaMulti-band OFDMStrong Advantage
Multi-band OFDMSlight Advantage
Neutral802.11a
Slight Advantage802.11a
Strong Advantage
PA Power Consumption
ADC Power Consumption
FFT Complexity
Viterbi Decoder Complexity
Band Select FilterPower Consumption
Band Select Filter Area
ADC Precision
Digital Precision
Phase Noise Requirements
Sensitivity to Frequency/Timing Errors
Design of Radio
Power / Mbps1. Assumes a 256-point FFT for IEEE 802.11a device.2. Assumes a 128-point FFT for IEEE 802.11a device.3. Even though the Multi-band OFDM ADC runs faster than the IEEE 802.11a ADC, the bit precision requirements are significantly smaller,
therefore the Multi-OFDM ADC will consume much less power.
1 23
September 2003
A. Batra, Texas Instruments et al.Slide 41
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDMAdvantages (1)
Suitable for CMOS implementation (all components).
Antenna and pre-select filter are easier to design (can possibly use off-the-shelf components).
Early time to market!
Low cost, low power, and CMOS integrated solution leads to:
Early market adoption!
September 2003
A. Batra, Texas Instruments et al.Slide 42
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDMAdvantages (2)
Inherent robustness in all the expected multipath environments.
Excellent robustness to ISM, U-NII, and other generic narrowband interference.
Ability to comply with world-wide regulations: Bands and tones can be dynamically turned on/off to comply with
changing regulations.
Coexistence with current and future systems: Bands and tones can be dynamically turned on/off for enhanced
coexistence with the other devices.
Scalability with process: Digital section complexity/power scales with improvements in technology
nodes (Moore’s Law). Analog section complexity/power scales slowly with technology node.
September 2003
A. Batra, Texas Instruments et al.Slide 43
doc.: IEEE 802.15-03/267r6
Submission
Summary
The proposed system is specifically designed to be a low power, low complexity all CMOS solution.
Expected range for 110 Mb/s (90% link success probability): 20.5 meters in AWGN, and approximately 11 meters for a Mode 1 device and greater than 9 meters for a Mode 2 device in realistic multi-path environments.
Expected power consumption for 110 Mb/s using 130 nm CMOS process: Mode 1 DEV: 117 mW (TX), 205 mW (RX), 18 W (deep sleep). Mode 2 DEV: 186 mW (TX), 271 mW (RX), 18 W (deep sleep).
Multi-band OFDM is coexistence friendly and complies with world-wide regulations.
Multi-band OFDM offers multi-mode devices (scalability).
Multi-band OFDM offers the best trade-off between the various system parameters.
September 2003
A. Batra, Texas Instruments et al.Slide 44
doc.: IEEE 802.15-03/267r6
Submission
Backup slides
September 2003
A. Batra, Texas Instruments et al.Slide 45
doc.: IEEE 802.15-03/267r6
Submission
Self-evaluation Matrix (1) REF.
IMPORTANCE LEVEL
PROPOSER RESPONSE
Unit Manufacturing Complexity (UMC)
3.1 B +
Signal Robustness Interference And Susceptibility 3.2.2
A +
Coexistence 3.2.3 A +
Technical Feasibility
Manufacturability 3.3.1 A +
Time To Market 3.3.2 A +
Regulatory Impact 3.3.3 A +
Scalability (i.e. Payload Bit Rate/Data Throughput, Channelization – physical or coded, Complexity, Range, Frequencies of Operation, Bandwidth of Operation, Power Consumption)
3.4 A
+
Location Awareness 3.5 C +
CRITERIA REF.
IMPORTANCE LEVEL
PROPOSER RESPONSE
MAC Enhancements And Modifications
4.1. C +
September 2003
A. Batra, Texas Instruments et al.Slide 46
doc.: IEEE 802.15-03/267r6
Submission
Self-evaluation Matrix (2)CRITERIA REF.
IMPORTANCE LEVEL
PROPOSER RESPONSE
Size And Form Factor 5.1 B
+
PHY-SAP Payload Bit Rate & Data Throughput Payload Bit Rate 5.2.1
A +
Packet Overhead 5.2.2 A +
PHY-SAP Throughput 5.2.3 A +
Simultaneously Operating Piconets
5.3 A +
Signal Acquisition 5.4 A +
System Performance 5.5 A +
Link Budget 5.6 A +
Sensitivity 5.7 A +
Power Management Modes 5.8 B +
Power Consumption 5.9 A +
Antenna Practicality 5.10 B +
September 2003
A. Batra, Texas Instruments et al.Slide 47
doc.: IEEE 802.15-03/267r6
Submission
Convolutional Encoder
Assume a mother convolutional code of R = 1/3, K = 7. Having a single mother code simplifies the implementation.
Generator polynomial: g0 = [1338], g1 = [1458], g2 = [1758].
Higher rate codes are achieved by puncturing the mother code. Puncturing patterns are specified in latest revision of 03/268.
D D D D D DI nputData
Output Data A
Output Data B
Output Data C
September 2003
A. Batra, Texas Instruments et al.Slide 48
doc.: IEEE 802.15-03/267r6
Submission
Bit Interleaver: Mode 1 (3-band)
Bit interleaving is performed across the bits within an OFDM symbol and across at most three OFDM symbols. Exploits frequency diversity. Randomizes any interference interference looks nearly white. Latency is less than 1 s.
Bit interleaving is performed in three stages: First, 3NCBPS coded bits are grouped together. Second, the coded bits are interleaved using a NCBPS3 block symbol
interleaver. Third, the output bits from 2nd stage are interleaved using a (NCBPS/10)10
block tone interleaver. The end results is that the 3NCBPS coded bits are interleaved across 3
symbols and within each symbol.
If there are less than 3NCBPS coded bits, which can happen at the end of the header or near the end of a packet, then the second stage of the interleaving process is skipped.
September 2003
A. Batra, Texas Instruments et al.Slide 49
doc.: IEEE 802.15-03/267r6
Submission
Bit Interleaver: Mode 1 (3-band) Ex: Second stage (symbol interleaver) for a data rate of 110 Mbps
Ex: Third stage (tone interleaver) for a data rate of 110 Mbps
NCBPS 3
Read I n
Read Out
x1 x2 ... x300 x1 x4 ... x298 x2 x5 ... x299 x3 x6 ... x300
600 Coded bits = 6 OFDM symbols 600 Coded bits = 6 OFDM symbols
NCBPS/10 10
Read I n
Read Out
y1 y2 ... y300
y1 y11 ... y91 y2 y12 ... y92 ... y10 y20 ... y100y101 y111 ... y191 y102 y112 ... y192 y110 y120 ... y200y201 y211 ... y291 y202 y212 ... y292 y210 y220 ... y300
600 Coded bits = 6 OFDM symbols 600 Coded bits = 6 OFDM symbols
September 2003
A. Batra, Texas Instruments et al.Slide 50
doc.: IEEE 802.15-03/267r6
Submission
Multi-band OFDM: RX Architecture
Block diagram of an example RX architecture:
Architecture is similar to that of a conventional and proven OFDM system. Can leverage existing OFDM solutions for the development of the Multi-band OFDM physical layer.
Pre-SelectFilter
LNA
sin(2fct)
cos(2fct)
Syn
chro
niza
tion
Rem
ove
CP
FFT
FEQ
Rem
ove
Pilo
ts
Vit
erbi
Dec
oder
De-
scra
mble
r
AGC
CarrierPhaseand
TimeTracking
De-
Inte
rlea
ver
I
Q
LPF
LPF
VGA
VGA
ADC
ADC
OutputData
September 2003
A. Batra, Texas Instruments et al.Slide 51
doc.: IEEE 802.15-03/267r6
Submission
Simulation Parameters
Assumptions: System as defined in 03/268. Clipping at the DAC (PAR = 9 dB). Finite precision ADC (4 bits @ 110/200 Mbps).
Degradations incorporated: Front-end filtering. Multi-path degradation. Clipping at the DAC. Finite precision ADC. Crystal frequency mismatch (20 ppm @ TX, 20 ppm @ RX). Channel estimation. Carrier/timing offset recovery. Carrier tracking. Packet acquisition.