charles msc defence
TRANSCRIPT
-
8/2/2019 Charles Msc Defence
1/33
IEEE 802.11p Vehicle to Vehicle
(V2V) Communication
Charles Joseph OGALACIU Research Group
Cyprus International UniversityJanuary 12, 2012
-
8/2/2019 Charles Msc Defence
2/33
Agenda
1. Introduction2. Evolution of 802.11p Technology
3. Vehicular communication at a Glance and
Wireless Access in Vehicular Environments(WAVE)4. Modeling Agilents Advanced Design Systems (ADS)
According to IEEE 802.11p for the vehicular environment.
5.
What Well Cover Today!!!
Simulated Results for Fading Channel
-
8/2/2019 Charles Msc Defence
3/33
Executive Summary
The Concept
TheOpportunity
Motivation
vehicle-to-vehicle (V2V).
Smart Cars
Safer roads Less traffic Fading
-
8/2/2019 Charles Msc Defence
4/33
Introduction
In 2009 the American Federal communicationcommission (FCC) dedicated 75 MHz band widthof 5.850-5.925 GHz for V2V wireless
communication. The vehicular band is locatedright above Unlicensed National InformationInfrastructure (U-NII) radio band. In 2004 a taskgroup under IEEE and OSI committee developed
an initiative that will enhance common Physical(PHY) for Vehicle to Vehicle (V2V) and Vehicle toInfrastructure (V2I) communication at 5.9 GHz.
-
8/2/2019 Charles Msc Defence
5/33
Summaries of the IEEE 802.11 Standard
Years Standards Speed Frequency Band
1997 802.11 -97 1Mbps 2 Mbps 2.4 GHz band
1999 802.11a Up to 54 mbps 5 GHz band
1999 802.11b 5.5Mbps 11Mbps 2.4 GHz band
2003 802.11g 54Mbps 108Mbps 2.4 GHz band
2007 802.11n 100 Mbps 2.4 GHz band
-
8/2/2019 Charles Msc Defence
6/33
Figure1: WLAN block diagram for IEEE 802.11p scenarios
-
8/2/2019 Charles Msc Defence
7/33
In single carrier the information are
represented inform of a bits called
symbol. It has a disadvantage of
transmitting tiny symbol with large
amount of bandwidth making it an
inefficient frequency carrier. symbol are
also venerable to signal reflection,impulse noise and other impairments
In Frequency Division
multiplexing (FDM), the wholedata rate sent is divided betweenthe various subcarriers. However,in this case interference onlyaffects one of the frequency sub-bands, while the others are
unaffected.
Why Orthogonal Frequency division
Multiplexing (OFDM)
-
8/2/2019 Charles Msc Defence
8/33
IEEE 802.11p OFDM block diagram
-
8/2/2019 Charles Msc Defence
9/33
Physical layer Implementation Comparison of
IEEE 802.11a and IEEE 802.11p.
-
8/2/2019 Charles Msc Defence
10/33
WAVE (Wireless Access in VehicularEnvironments)
The standard consists of four sub standards which arestated below
IEEE 1609.1
IEEE 1609.2
IEEE 1609.3
IEEE 1609.4
-
8/2/2019 Charles Msc Defence
11/33
DSRC ChannelAllocation
-
8/2/2019 Charles Msc Defence
12/33
Vehicular Propagation Channels
Path loss
Signal Fading
Rician Fading DistributionRayleigh Fading Distribution
-
8/2/2019 Charles Msc Defence
13/33
-
8/2/2019 Charles Msc Defence
14/33
Simulation model of IEEE 802.11p base AgilentsAdvanced Design Systems (ADS)
-
8/2/2019 Charles Msc Defence
15/33
ADS Transmitter block diagram model
-
8/2/2019 Charles Msc Defence
16/33
Transmitter Component
WLAN Data
The PPDU is generated at the WLAN Data; the frame format
consists of 16 bits. The first 6 bits (0 to 6) is set to zero, these bits
are used for synchronizing the descrambler at the receiver. Theremaining bits (7 to 15) reserved for future use. The PPDU tail
bit field comprises of 6 bits of 0, which is used to return the
convolutional encoder to the zero state.
Scrambler
-
8/2/2019 Charles Msc Defence
17/33
EncoderScrambled data is transferred to the convolutional encoder byusing linear shift registers. Some redundancy bit stream is
introduced in a controlled way. Its main aim is to correct errors in
coding which enables the receiver to combat the impairments ofthe channel and, hence, achieve reliable communication.
Data interleaving
-
8/2/2019 Charles Msc Defence
18/33
Modulation & mapping
PreambleIEEE 802.11p PLCP field is composed of four parts: short preamble,
long preamble, signal and data fields.
-
8/2/2019 Charles Msc Defence
19/33
IFFT and FFT
Multiplexing process of OFDM Frames
The logical subcarrier numbers are then mapped into
frequency offset index -26 to 26, while skipping
subcarriers -21, -7, 0, 7 and 21. After that, theassembler block enables the pilot subcarriers to be
inserted into the positions of -21, -7, 7 and 21
Error Vector Magnitude
-
8/2/2019 Charles Msc Defence
20/33
Channel Model
Environment & Power Classes 802.11p
-
8/2/2019 Charles Msc Defence
21/33
Vehicular Antenna & Properties
-
8/2/2019 Charles Msc Defence
22/33
Base Station AntennaIn this research, a base station antennas
of EIA/TIA-329-B, specification is used
Vehicular AntennaA mobile antenna of "EIA/TIA-329-B-1
specification is used in this vehicular
research.
-
8/2/2019 Charles Msc Defence
23/33
Receiver Side
-
8/2/2019 Charles Msc Defence
24/33
Frequency Domain Equalizer
When receiver realizes a distortion, an equalizer combats the
distortion introduced by the channel.
OFDM symbol de-multiplexer
This section enables the OFDM symbol to be de-multiplexed(e.g. BPSK, QPSK, and 16-QAM modulation) into data andpilot forms. The complex signal is converted to data andpilots .
-
8/2/2019 Charles Msc Defence
25/33
Demodulator Bank (De-mapping)
Evaluation of the reliability modules
-
8/2/2019 Charles Msc Defence
26/33
Performance on a Typical Urban Fading
Channel
-
8/2/2019 Charles Msc Defence
27/33
Above is a simulated result BER against SNR for LOS in a typical urban area BPSK has
a BER of 2.954E-5 at 4.750. QPSK has a low BER of 4.844E-4 at 4.750 and while 16 QAM
has BER of 0.004 at 4.750. From the above result BPSK has the lowest BER against SNR
802 11p BER In A Typical Urban Area For NLOS Fading Channel
-
8/2/2019 Charles Msc Defence
28/33
-1 0 1 2 3 4 5 6 7-2 8
1E-5
1E-4
1E-3
1E-2
1E-1
1E-6
6E-1
Eb/No (dB)
BER
802.11p BER In A Typical Urban Area For NLOS Fading Channel
BPSK 3/4
QPSK 3/4
16 QAM 1/2
In the case of NLOS the result indicated that BPSK has a low BER of 1.018E-4 at 4.429.QPSK has a BER of 0.001 at 4.429. And for the 16 QAM it has a low BER of 0.006 at 4.429.
The performance of Figure 13 result is observed to degrade as a result of multipath component and non line of sight between the transmitter and the receiver. Inaddition the result indicates that the environment is associated with a lot building and
Doppler spread that hinder the effective transmission of signal along the channel
-
8/2/2019 Charles Msc Defence
29/33
Performance on Free space
802 11p BER In A Free Space For LOS Fading Channel
-
8/2/2019 Charles Msc Defence
30/33
-1 0 1 2 3 4 5 6 7 8 9-2 10
1E-5
1E-3
1E-1
1E-7
5E-1
Eb/No(dB)
BER
802.11p BER In A Free Space For LOS Fading Channel
BPSK 3/4
QPSK 3/4
16 QAM 1/2
The figure 5.7 is a representation of LOS result for BER against SNR indicate 0.492 at -2.000
for BPSK and 9.766E-7 at 7.000, the QPSK the result indicate 0.488 at -2.000 for the starting
point and 1.733E-5 at 7.000 for the ending point. And for the 16 QAM it has a starting point of
0.480 at -2.000 with an ending point of 1.074E-5 at 10.000.
-
8/2/2019 Charles Msc Defence
31/33
-1 0 1 2 3 4 5 6 7 8 9-2 10
1E-5
1E-4
1E-3
1E-2
1E-1
1E-6
5E-1
Eb/No(dB)
BER
802.11p BER In A Free Space For NLOS Fading Channel
BPSK 3/4QPSK 3/416QAM 1/2
The result above states that BPSK has a BER of 1.416E-5 at 6.250 but it is also
glaring that QPSK and 16 QAM are almost the same indicating that it not a good
choice to use QPSK . However, the result indicates the Figure 5.7 result has the
lowest BER compare to figure 5.8. Due to LOS that exist between the two car
antennas
-
8/2/2019 Charles Msc Defence
32/33
-
8/2/2019 Charles Msc Defence
33/33
THANK YOU !
Questions