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Evolution of IEEE 802.11
Original 802.11
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Evolution of IEEE 802.11 PPDU format
Agenda
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IEEE 802.11 working group formed in 1990 First release of IEEE 802.11 standard in June 1997 First release had two transmission modes
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
1GPP-St | 09/01 | 4
u 802.3
Ethernet u 802.4 Token Bus u 802.5 Token Ring
1GPP-St | 09/01 | 10
PLCP preamble and header generation
IEEE 802.11b solution with SMIQ
IEEE 802.11b
System overview
Agenda
Physical Layer
Evolution of IEEE 802.11 PPDU format
u
Agenda Evolution of IEEE 802.11 PPDU format
802.11 DSSS had originally two modes
Mbps data rate using DBPSK u 2 Mbps data rate using DQPSK u both had a 11 Mcps chip rate
IEEE 802.11b solution with SMIQ
Evolution of IEEE 802.11
Standard overview
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Agenda Evolution of IEEE 802.11 PPDU format
802.11 defines the Medium Access (MAC) and Physical layer of a LAN/MAN (local/metropolitan)
1GPP-St | 09/01 |
802.11a 6 / 12 / 24 Mbps opt. 9 / 18 / 36 / 54 Mbps
IEEE 802.11b
System parameters
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Agenda Evolution of IEEE 802.11 PPDU format
TDD (time division duplex) system
1GPP-St | 09/01 | 5
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Transmission rates are 1 or 2 Mbps
Radio
Infrared
FHSS
DSSS
IEEE 802.11b solution with SMIQ
Evolution of IEEE 802.11
Additions to the 802.11 standard
1GPP-St | 09/01 | 8 IEEE 802.11b solution with SMIQ
PLCP = Physical Layer Convergence Protocol
IEEE 802.11b
System overview
Agenda
Physical Layer
Evolution of IEEE 802.11 PPDU format
u1
Radio
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Further development
u 802.11a
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
u Faster
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PPDU format
Reasons for the sudden change
data rates u Aggressive marketing by vendors u Intel decided to switch from HomeRF to 802.11b
u Sales
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
Data Data
Packet Packet Builder Builder
Scrambling Scrambling
Spreading Spreading & & Modulation Modulation
I Q
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™
Data Data
Packet Packet Builder Builder
Scrambling Scrambling
Spreading Spreading & & Modulation Modulation
I Q
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
IEEE 802.11b solution with SMIQ
1GPP-St | 09/01 | 1
IEEE 802.11b solution with SMIQ
Agenda
u u
Evolution of IEEE 802.11 PPDU format
Agenda
u u u u u
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
1GPP-St | 09/01 | 2
Evolution of IEEE 802.11 PPDU format System overview Modulation and spreading Special test modes Signal generation with WinIQSIM™ 802.11b SigGen configuration
1GPP-St | 09/01 | 6
(OFDM) at 5 GHz in Spring 1999 u 802.11b at 2.4 GHz in Summer 1999
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DSSS
802.11a
802.11b added two data rates
u 5.5
Mbps data rate using CCK u 11 Mbps data rate using CCK u Chip rate stays at 11 Mcps
1ps 11 Mbps
IEEE 802.11b solution with SMIQ
Evolution of IEEE 802.11
Physical Layer overview
Physical Layer Infrared (IR) Frequency Hopping Spread Spectrum 2.4 GHz (FHSS) Direct Sequence Spread Spectrum 2.4 GHz (DSSS) 802.11 IR 1 / 2 Mbps 802.11 FHSS 1 / 2 Mbps 802.11 DSSS 1 / 2 Mbps 802.11b 1 / 2 / 5.5 / 11 Mbps Orthogonal Frequency Division Multiplexing 5 GHz (OFDM)
ua
device can either send or receive, not both at same time
Packet oriented transmission
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
7 IEEE 802.11b solution with SMIQ
Agenda Evolution of IEEE 802.11 PPDU format
System overview Modulation and spreading Special test modes Signal Generation with WinIQSIM™ 802.11b SigGen configuration
Agenda Evolution of IEEE 802.11
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802.11b is winning the battle against HomeRF
u In
2000: 58% of all wireless nodes sold used HomeRF u In 2001: 71% of all wireless nodes shipped will be 802.11b