protocol standerds for all devices

1. Introduction to
IEEE 802.11 Protocols
.
By
Narender reddy
13W91A0421
TECHNICAL SEMINAR

2. Outline:
 Introduction
 IEEE 802.11 Protocol Layers
 IEEE 802.11 standards
 Summary
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3. Introduction:
 Access anytime, anywhere internet.
 IEEE 802.11 is a set of standards for wireless Local Area Networks
(WLANs) computer communication, developed by the IEEE
LAN/MAN Standards Committee.
 1997 working group approved IEEE 802.11 as the world’s first
wireless LAN standard.
 IEEE 802.11 is a subset of IEEE 802 LAN standard.
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4. IEEE 802.11 Protocol:
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Covers physical and data link layer acc. to OSI
 Physical layer:
 Data Link layer
Spread Spectrum
FHSS
DSSS
Logic Link Control (LLC)
Media Access Control (MAC)

5. IEEE 802.11 standards :
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6. 802.11 is a set of IEEE standards that govern wireless
networking transmission methods. They are commonly used
today in their 802.11a, 802.11b, 802.11g, 802.11n and
802.11ac ,802.11ad versions to provide wireless connectivity
in the home, office and some commercial establishments.
USAGE:

7. IEEE 802.11 standards :
IEEE 802.11 b(1999)
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Frequency = 2.4 GHz (ISM band)
Maximum Speed =11 Mbps
Range = about 38meters(Varies)
Encoding Scheme = DSSS
Modulation Technique= BPSK(1 Mbps),
DQPSK(2 Mbps), CCK(5.5 Mbps,11Mbps)
Released in the year 1999

8. IEEE 802.11 standards :
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9. IEEE 802.11 standards :
IEEE 802.11 a
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Frequency = 5 GHz
Maximum Speed = 54 Mbps
Range = about 35 meters(Varies)
Encoding Scheme = OFDM
Released in the year 1999

10. IEEE 802.11 standards :
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IEEE 802.11 a
Multipath Effect(Multipath Fading)
is simply a term used to describe the multiple
Paths the radio wave may follow between
transmitter and receiver

11. IEEE 802.11 standards :
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IEEE 802.11 a
Orthogonal Frequency Division Multiplexing(OFDM)
OFDM a digital multi-carrier modulation method. A large
number of closely-spaced orthogonal sub-carriers are used to
carry data.
Although the principles and some of the benefits have
been known since the 1960s, OFDM is popular for
wideband communications today by way of low-cost digital
signal processing components that can efficiently calculate
the FFT.

12. IEEE 802.11 standards :
IEEE 802.11 a
A simple idealized OFDM system
(Implementation using FFT Algorithm)
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Receiver :

13. IEEE 802.11 standards :
IEEE 802.11 a
OFDM Pros &Cons
Robust against narrow-band co-channel interference.
Robust against intersymbol interference (ISI) and fading caused by multipath
propagation.
High spectral efficiency as compared to conventional modulation schemes, spread
spectrum, etc.
Efficient implementation using Fast Fourier Transform (FFT).
Sensitive to Doppler shift.
Sensitive to frequency synchronization problems.
High peak-to-average-power ratio (PAPR), requiring linear transmitter circuitry, which
suffers from poor power efficiency. 13

14. IEEE 802.11 standards :
14 [5]

15. IEEE 802.11 standards :
IEEE 802.11 g
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 Frequency= 2.4 GHz
 Maximum Speed = 54 Mbps
 Range = about 38 meters(Varies)
 Encoding Scheme = OFDM
 Bandwidth =20mhz
 Released in the year 2003

16. IEEE 802.11 standards :
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17. IEEE 802.11 standards :
IEEE 802.11n
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 Frequency = 5 GHz,2.4 GHz
 Modulation = OFDM
 Addition of Mimo
 Maximum Speed = 150 Mbps
 Range = about 70 meters(Varies)
 Encoding Scheme = OFDM
 Released in the year =2009

18. IEEE 802.11 standards :
IEEE 802.11 n
Multiple Input Multiple Output(MIMO)
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In radio, Multiple-input and
Multiple-output is used of
multiple antennas at both the
transmitter and receiver to
improve communication
performance. It is one of
several forms of smart antenna
technology.

19. IEEE 802.11 standard :
IEEE 802.11ad
Frequency band=60GHz
Modulation=SC,OFDM
Maximum speed=6.7Gbs/sec
Range about=1-10m
Bandwidth=2160mhz
Released in the year =2012
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20. ASUS Product :
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24. IEEE 802.11ay:
 Frequency band=60mhz
 Bandwidth =8000
 Maximum speed=100Gb/s
 Released date= 2017
 Modulation= OFDM, single carrier

25. Summary:
IEEE 802.11ad standard Significantly improves throughput and
range compared with older 802.11 standards.
 802.11ad is the only 802.11standard that operates in either the
60GHz and 2.4GHz frequency bands.
It is the first to standardize the use of multiple input, multiple output
(MIMO) antenna design.
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