1 ijaems nov-2015-1-a comparative performance analysis of 4x4 mimo-ofdm system using spatial multiplexing under various wireless channels

International Journal of Advanced Engineering, Management and Science (IJAEMS) [Vol-1, Issue-8, Nov- 2015]
ISSN : 2454-1311
www.ijaems.com Page | 1
A comparative Performance Analysis of 4x4
MIMO-OFDM system using Spatial
Multiplexing under various Wireless Channels
Kishore Kumar Mali
M.Tech. Scholar, Department of ECE, College of Technology and Engineering, Udaipur, Rajasthan, India
Abstract— Multiple Input Multiple Output (MIMO)
technology refers to wireless communication systems
employing multiple antennas at either the transmitter end
or the receiver end or both. In recent times, use of
multiple transmit and receive antenna for enhancing
spectral efficiency in a wireless system has established
much interest in research field. The solution to obtain
superior data rates and better range performance at the
same time is OFDM integrated with MIMO technique
which is based on IEEE 802.11n standard. The main
trouble in front of the wireless multipath propagation is
the interference between information symbols transmitted
through neighbouring channels also called as Inter
Symbol Interference (ISI). This could be avoided if we use
OFDM technology. Thus MIMO combined with OFDM
has got significant importance in future wireless
communication system. The major properties of MIMO
system involve Spatial Diversity and Spatial Multiplexing
which are the main factors to discuss and matter of
concern to achieve reliability and high speed data rate. In
this paper, we study the performance gain of MIMO-
OFDM systems. The main investigation carried out in the
following paper is to deal with various Wireless channel
models in Spatial Multiplexing (SM) mode. The paper
deals with MIMO-OFDM system analysis in various
Wireless channel models (Rayleigh, Rician, Nakagami
and 3GPP channel Environment) focusing on error rate
performance, throughput and Spectral gain in 4x4 MIMO
scheme under OFDM system. Evaluation of Bit Error
Rate and throughput with respect to varying Eb/No for
4x4 MIMO-OFDM in Spatial Multiplexing mode,
employing 16 QAM modulation with N=128 OFDM
subcarriers employing MMSE detection, is the baseline of
this paper.
Keywords— 3GPP, MIMO, MMSE, OFDM, QAM, SM,
Eb/No
I. INTRODUCTION
Next generation wireless communication system will
demand purely high speed communication links, high
quality multimedia and data services with high efficiency
and reliability. In order to achieve high bit data rate
services such as online gaming, video conferencing or
web browsing, the next generation wireless
communication systems would have to improve their
range, quality of service (QoS), bandwidth, throughput
and power efficiency [1]. MIMO has been standardized
for 3G, 4G wireless LANs and is now in far flung
commercial use. Multiple Input Multiple Output
technology has achieved widespread attention in recent
years as a promising wireless technology. Such systems
offer the dual benefits of wireless channel fading
mitigation through diversity reception and link throughput
enhancement through Spatial Multiplexing [2]. The SM is
typically well suited to users with good channel
conditions that is, to users near the cell centre with a high
signal-to-noise ratio [3]. One of the most key feature of
wireless channels is Multipath propagation. The faster the
data rate, the higher the probability that multipath
propagation will cause Inter Symbol Interference (ISI)
[2]. Due to the multipath propagation, signal suffers rapid
and severe fluctuations in amplitude and phase. The
solution to obtain noteworthy superior data rates and
enhanced range performance at the same time is MIMO-
OFDM which is based on 802.11n standard. This
increases the link capacity by concurrently transmitting
multiple data streams using multiple transmit and receive
antennas. OFDM is the technique which is used to
mitigate the multipath propagation problem and MIMO is
useful for the efficient usage of spectral bandwidth thus
combining these techniques results in wireless system that
has best spectral coverage, reliable transmission in highly
obstructive wireless environment. By multiplying spectral
efficiency, MIMO-OFDM opens the door to a range of
new applications and enables more cost-effective
implementation for existing applications [4].
For our simulation MATLAB simulation tool is utilized
which played a significant role to achieve required results.
In this paper MATLAB R2015a version is used for
simulation of Bit Error Rate and throughput for different
channel environment.

International Journal of Advanced Engineering, Management and Science (IJAEMS) [Vol
www.ijaems.com
II. OVERVIEW OF SPATIAL
MULTIPLEXING MODE (SM)
Spatial multiplexing obeys space-time diversity technique
whose foundation design is to transmit independent
information links from each transmit antenna. Spatial
multiplexing can offer an increase in the transmission rate
and spectral efficiency, because each spatial channel
carries independent data, thereby escalating the data rate
of the system. To achieve this goal, we may opt to place
different portions of the information on different spatial
paths, providing improved data rate of the system.
spatial multiplexing, if the scattering by the environment
is well enough, multiple independent spatial links are
formed in the same allocated bandwidth. Thus the
multiplexing gain, also referred as number of deg
freedom, comes at no extra cost on bandwidth or power.
Multiplexing gain or degrees of freedom in a MIMO
configuration is equal to min (m,n) where m is the
number of transmit antennas and n is the number of
receive antennas [5].
Fig. 2 displays a simple spatial multiplexing system using
a 2x2 MIMO system. In this study, the first information
symbol, s0, is transmitted from the transmit antenna Tx0,
and the second information symbol, s1, is transmitted
from transmit antenna, Tx1. During the first symb
the propagation of these two data symbols occurs
concurrently. The data symbols s2 and s3 are concurrently
transmitted during the next symbol time. In this action,
alternate symbols are sent from each antenna and each
symbol is only transmitted once, providing doubled data
rate. Compared to STC, this technique is entirely different
as no information symbols are repeated over two symbol
times across the two antennas. Here, it is assumed that
antennas are properly placed so that fading coefficients
are different. A complex wireless fading coefficient h00
exist between Tx0 to Rx0. A complex wireless fading
coefficient h10 exist between Tx0 to Rx1
analogous relationship between Tx1 and the remaining
two receive antennas resulting four non-identical complex
fading coefficients h00, h01, h10 and h11 [6].
After transmitting all the data symbols through the
channel using spatial multiplexing, the receiver receive
the signal r0, at antenna Rx0, as an addition of the s
s1 information symbols, corrupted with complex fading
coefficients H00 and H01 respectively. Concurrently, the
Rx1 receives s0 and s1 affected with complex fading
coefficients, H10 and H11 respectively. Here, we are
neglecting the effect of noise. Therefore received signal at
each received antenna can be modeled as
… 1
… 2
OVERVIEW OF SPATIAL
MULTIPLEXING MODE (SM)
time diversity technique
whose foundation design is to transmit independent
information links from each transmit antenna. Spatial
ransmission rate
each spatial channel
, thereby escalating the data rate
of the system. To achieve this goal, we may opt to place
on different spatial
viding improved data rate of the system. In
spatial multiplexing, if the scattering by the environment
is well enough, multiple independent spatial links are
formed in the same allocated bandwidth. Thus the
multiplexing gain, also referred as number of degree of
freedom, comes at no extra cost on bandwidth or power.
Multiplexing gain or degrees of freedom in a MIMO
configuration is equal to min (m,n) where m is the
number of transmit antennas and n is the number of
mple spatial multiplexing system using
a 2x2 MIMO system. In this study, the first information
symbol, s0, is transmitted from the transmit antenna Tx0,
and the second information symbol, s1, is transmitted
from transmit antenna, Tx1. During the first symbol time
the propagation of these two data symbols occurs
concurrently. The data symbols s2 and s3 are concurrently
transmitted during the next symbol time. In this action,
alternate symbols are sent from each antenna and each
e, providing doubled data
Compared to STC, this technique is entirely different
as no information symbols are repeated over two symbol
Here, it is assumed that
antennas are properly placed so that fading coefficients
are different. A complex wireless fading coefficient h00
A complex wireless fading
coefficient h10 exist between Tx0 to Rx1. There is an
relationship between Tx1 and the remaining
identical complex
fading coefficients h00, h01, h10 and h11 [6].
After transmitting all the data symbols through the
channel using spatial multiplexing, the receiver receives
the signal r0, at antenna Rx0, as an addition of the s0 and
information symbols, corrupted with complex fading
respectively. Concurrently, the
affected with complex fading
respectively. Here, we are
Therefore received signal at
The spatial signatures of the two signals, r0 and r1 are
separated under favourable
section, having knowledge of the channel state, can easily
recover symbols s0 and s1by further signal processing. If
there are m transmit antenna a
equation can be rewritten in the following matrix form,
....
…
....
....
…
In order to recover the information from the received
signals, the channel coefficient matrix [H] needs to be
inverted. The matrix inversion becomes difficult if the
channel coefficients in [H] are highly correlated [6].
Fig. 1: 2x2 MIMO systems employing Spatial
Multiplexing
III. MIMO WITH ORTHOGONAL
FREQUENCY DIVISION
The motivation behind the MIMO system is to achieve
higher throughput and the motivation behind the OFDM
system is to convert frequency selective into set of
parallel flat fading channels. OFDM compensates for
Inter symbol Interference (ISI),
for its diversity/multiplexing benefits. So we couple the
ability of both the system to achieve high throughput as
well as simplified processing at the receiver that is
converting the frequency selective channel into the set of
parallel flat fading channels. Hence, MIMO
combination MIMO communication with OFDM. Similar
to OFDM, MIMO-OFDM converts a frequency selective
MIMO channel into multiple parallel flat fading channels.
From the theory of OFDM, in a MIMO
IDFT and IFFT operation has to be performed at each
transmit antenna. Multiple Transmit antennas are used to
transmit data modulated by OFDM in a MIMO
system. At the receiver, after OFDM demodulation, the
signal are detected back by decoding every sub
from all the transmit antennas [7].
ISSN : 2454-1311
Page | 2
The spatial signatures of the two signals, r0 and r1 are
favourable conditions. The receiver
section, having knowledge of the channel state, can easily
recover symbols s0 and s1by further signal processing. If
there are m transmit antenna and n receive antenna then
equation can be rewritten in the following matrix form,
....
....
....
… 3
In order to recover the information from the received
e channel coefficient matrix [H] needs to be
inverted. The matrix inversion becomes difficult if the
channel coefficients in [H] are highly correlated [6].
Fig. 1: 2x2 MIMO systems employing Spatial
Multiplexing
MIMO WITH ORTHOGONAL
FREQUENCY DIVISION MULTIPLEXING
The motivation behind the MIMO system is to achieve
higher throughput and the motivation behind the OFDM
system is to convert frequency selective into set of
parallel flat fading channels. OFDM compensates for
Inter symbol Interference (ISI), while MIMO is employed
for its diversity/multiplexing benefits. So we couple the
ability of both the system to achieve high throughput as
well as simplified processing at the receiver that is
converting the frequency selective channel into the set of
lel flat fading channels. Hence, MIMO-OFDM is a
combination MIMO communication with OFDM. Similar
OFDM converts a frequency selective
MIMO channel into multiple parallel flat fading channels.
From the theory of OFDM, in a MIMO-OFDM system,
FT and IFFT operation has to be performed at each
transmit antenna. Multiple Transmit antennas are used to
transmit data modulated by OFDM in a MIMO-OFDM
system. At the receiver, after OFDM demodulation, the
signal are detected back by decoding every sub-channels
from all the transmit antennas [7].

www.ijaems.com
3.1 MIMO-OFDM Operations
3.1.1 Transmitter Section
S/P Demux for Transmit Antennas: Serial to parallel
Demultiplexing of the data bits for the transmit
antennas.
16-QAM Modulator: It converts the data into a
sequence of modulated symbols in complex format.
S/P Demux: On each transmit antenna, symbols are
again demultiplexed for further IFFT operation.
N pt IFFT: On Each block of symbol, N point IFFT is
performed. IFFT operation is used to shift the signal
from time domain to frequency domain. It takes N
input symbols at one time where N is the number of
subcarriers in the system.
P/S: After N point IFFT, symbols are multiplexed by
parallel to serial convertor.
CP: The symbols are added with cyclic prefix.
Fig. 2: OFDM signal with cyclic prefix
By this manner, each symbol is processed and transmitted
to tth
antennas.
3.1.2 Receiver Section
In the similar fashion corresponding receiver operations
are performed in MIMO-OFDM.
CP: Added Cyclic prefix are removed from the
symbols.
Fig. 3: Removal of cyclic prefix from OFDM signal
16-QAM Demodulator: It converts modulated data
into a sequence of demodulated symbols.
S/P Demux: On each receive antenna, symbols are
demultiplexed for further FFT operation.
N pt FFT: On Each block of symbol, N point FFT is
performed. FFT block is employed to shift the
received time-domain signal into frequency
MIMO Detection: On each OFDM sub
MIMO detection is performed. Appropriate
technique is employed on each OFDM subcarriers.
P/S Mux: After MIMO detection, symbols are
multiplexed by parallel to serial convertor.
Corresponding symbol blocks are decoded at P/S
Demultiplexer.
S/P Demux for Transmit Antennas: Serial to parallel
Demultiplexing of the data bits for the transmit
QAM Modulator: It converts the data into a
ence of modulated symbols in complex format.
S/P Demux: On each transmit antenna, symbols are
again demultiplexed for further IFFT operation.
N pt IFFT: On Each block of symbol, N point IFFT is
performed. IFFT operation is used to shift the signal
e domain to frequency domain. It takes N
input symbols at one time where N is the number of
P/S: After N point IFFT, symbols are multiplexed by
CP: The symbols are added with cyclic prefix.
OFDM signal with cyclic prefix
By this manner, each symbol is processed and transmitted
In the similar fashion corresponding receiver operations
CP: Added Cyclic prefix are removed from the
cyclic prefix from OFDM signal
QAM Demodulator: It converts modulated data
into a sequence of demodulated symbols.
S/P Demux: On each receive antenna, symbols are
for further FFT operation.
N pt FFT: On Each block of symbol, N point FFT is
performed. FFT block is employed to shift the
domain signal into frequency-domain.
MIMO Detection: On each OFDM sub-channel
MIMO detection is performed. Appropriate detection
technique is employed on each OFDM subcarriers.
P/S Mux: After MIMO detection, symbols are
multiplexed by parallel to serial convertor.
Corresponding symbol blocks are decoded at P/S
IV. FLOW CHART OF THE PROPOSED
Fig. 4: Algorithm flowchart
Transmitter
Section
OFDM symbols corrupted by channel H
and AWGN noise
Generate channel coefficients
Append cyclic prefix
IFFT operation
Generate Transmit signal vectors for
Transmit Antennas
Create Modulation Object
Generate Random Stream for channel
Define QAM Modulation order
Specify Bit Energy to Noise Ratio
Specify Number of Subcarriers
Input the Number of Transmit and Receive
Antennas
Receiver
Section
BER and Throughput Calculation
MIMO-MMSE Detection
FFT operation
Create Demodulation Object
Remove cyclic prefix
ISSN : 2454-1311
Page | 3
FLOW CHART OF THE PROPOSED
WORK
Algorithm flowchart
Transmitter
Section
OFDM symbols corrupted by channel H
and AWGN noise
Generate channel coefficients
Append cyclic prefix
IFFT operation
Generate Transmit signal vectors for
Transmit Antennas
Create Modulation Object
Generate Random Stream for channel
Define QAM Modulation order
Specify Bit Energy to Noise Ratio
Specify Number of Subcarriers
Input the Number of Transmit and Receive
Antennas
Receiver
Section
BER and Throughput Calculation
MMSE Detection
FFT operation
Create Demodulation Object
Remove cyclic prefix

www.ijaems.com
V. SIMULATION PARAMETERS AND
RESULTS
In the following analysis, a 4x4 configuration for MIMO
OFDM is incorporated i.e. m=4 transmit antennas and
n=4 receive antennas. This simulation analysis integrates
baseband transmission with MIMO-OFDM using 40MHz
bandwidth. The Eb/No assessments are divided into three
categories i.e. low Eb/No (1-5) dB, medium Eb/No (5
dB and high Eb/No (>10) dB. Table 1 enlists the
simulation parameters and their corresponding
specifications.
Table 1: Simulation parameters
Parameters Specifications
Model MIMO-OFDM
Transmission Mode Spatial Multiplexing (SM)
Number of Transmit
Antennas (m)
4
Number of Receive
Antennas (n)
4
Number of Subcarriers
(N)
128
Modulation 16 QAM
Detection Scheme MMSE
Bandwidth 40 MHz
Channel type Rayleigh, Rician,
Nakagami, 3GPP channel
Models
5.1 Comparative analysis of BER vs Eb/No under
various Wireless channels in a MIMO-
with m=n=4 in SM Mode with N=128 Subcarriers
Fig. 5: Comparative analysis of BER vs Eb/No for
MIMO-OFDM-SM system under various Wireless
channel Environment
In the following observation, the comparative analysis of
BER vs Eb/No for various Wireless channels for a
SIMULATION PARAMETERS AND
In the following analysis, a 4x4 configuration for MIMO-
OFDM is incorporated i.e. m=4 transmit antennas and
analysis integrates
OFDM using 40MHz
bandwidth. The Eb/No assessments are divided into three
5) dB, medium Eb/No (5-10)
dB and high Eb/No (>10) dB. Table 1 enlists the
heir corresponding
Table 1: Simulation parameters
Specifications
OFDM
Spatial Multiplexing (SM)
Rayleigh, Rician,
Nakagami, 3GPP channel
5.1 Comparative analysis of BER vs Eb/No under
-OFDM system
Subcarriers
Fig. 5: Comparative analysis of BER vs Eb/No for
SM system under various Wireless
In the following observation, the comparative analysis of
BER vs Eb/No for various Wireless channels for a
MIMO-OFDM system with
carried out with N=128 subcarriers.
An alluring observation in this fig. 5 is that
simulation result with respect to BER in Rician
fading channel is better than Rayleigh, Nakagami,
Sub-Urban Macrocell, Urban Macrocell and Urban
Microcell channel Environment respectively.
A very significant amount of performance
improvement in terms of BER is observed in
Rayleigh and Rician fading channels, when the
system embedded with N=128 subcarriers is utilized
in low Eb/No region (1
conditions deteriorates or in a scenario where the
signal component is bound to experience distortion
and deep fading.
It is noteworthy to observe that in Nakagami, Sub
Urban Macrocell, Urban Macrocell and Urban
Microcell channel Environment, system e
N=128 subcarriers provides significant reduction in
BER in medium Eb/No region (5
It is observed that Rician fading Environment
achieved BER of 10-4
Rayleigh fading Environment achieved BER of 10
at 4.5 dB. For Nakagami, Sub
Urban Macrocell and Urban Microcell channel
Environment BER of 10
dB, 7.2 dB and 9 dB respectively.
Another appealing observation in this fig. 5 is that in
Rician fading channel BER of 10
dB which provides best result. In Nakagami fading
channel BER of 10-4
is achieved at 6.5 dB which
provides moderate result and Urban Microcell
channel Environment achieved BER of 10
which provides poorest result among all channel
environments. Table 2 enlists the required Eb/No to
reach a target BER of 10
Table 2: Comparative analysis of required Eb/No to
reach a target BER of 10
channel
Channel
Environment
EB/No (dB)
Rician 3.3
Nakagami 6.5
Urban Microcell 9
5.2 Comparative analysis of Throughput vs Eb/No
under various Wireless channels in a MIMO
system with m=n=4 in SM mode with N=128
Subcarriers
The following observation illustrates the comparative
analysis of Throughput vs Eb/No for various Wireless
ISSN : 2454-1311
Page | 4
OFDM system with m=n=4 in SM Mode is
carried out with N=128 subcarriers.
An alluring observation in this fig. 5 is that
simulation result with respect to BER in Rician
fading channel is better than Rayleigh, Nakagami,
ll channel Environment respectively.
A very significant amount of performance
improvement in terms of BER is observed in
Rayleigh and Rician fading channels, when the
system embedded with N=128 subcarriers is utilized
in low Eb/No region (1-5) dB where channel
conditions deteriorates or in a scenario where the
signal component is bound to experience distortion
It is noteworthy to observe that in Nakagami, Sub-
Microcell channel Environment, system enabled with
N=128 subcarriers provides significant reduction in
BER in medium Eb/No region (5-10) dB.
It is observed that Rician fading Environment
at nearly 3.3 dB whereas
Rayleigh fading Environment achieved BER of 10-4
r Nakagami, Sub-Urban Macrocell,
Urban Macrocell and Urban Microcell channel
Environment BER of 10-4
is achieved at 6.5 dB, 7
dB, 7.2 dB and 9 dB respectively.
Another appealing observation in this fig. 5 is that in
Rician fading channel BER of 10-4
is achieved at 3.3
dB which provides best result. In Nakagami fading
is achieved at 6.5 dB which
provides moderate result and Urban Microcell
channel Environment achieved BER of 10-4
at 9 dB
which provides poorest result among all channel
ironments. Table 2 enlists the required Eb/No to
reach a target BER of 10-4
among all channels.
Table 2: Comparative analysis of required Eb/No to
reach a target BER of 10-4
under different Wireless
channel
EB/No (dB) Performance
Best
Moderate
Worst
5.2 Comparative analysis of Throughput vs Eb/No
under various Wireless channels in a MIMO-OFDM
system with m=n=4 in SM mode with N=128
The following observation illustrates the comparative
analysis of Throughput vs Eb/No for various Wireless

www.ijaems.com
channels in a MIMO-OFDM system with m=n=4 in SM
mode with N=128 subcarriers.
It can be clearly seen from the fig. 6 that the
simulation result of throughput in Rician fading
channel is better than Rayleigh, Nakagami, Sub
As it can be observed that in Rician fading channel,
maximum throughput is achieved at 4 dB wher
Rayleigh fading channel maximum throughput is
achieved at 6 dB. For Nakagami, Sub
Macrocell, Urban Macrocell and Urban Microcell
channel Environment maximum throughput is
achieved at 8 dB, 8 dB, 9 dB and 10 dB respectively.
Fig. 6: Comparative analysis of Throughput vs Eb/No for
MIMO-OFDM-SM system under various Wireless
channel
An enthralling observation in this fig. 6 is that Rician
fading channel achieves maximum throughput at
lowest Eb/No of 4 dB, providing best result. In
Nakagami and Sub-Urban Macrocell Environment,
maximum throughput is achieved at 8 dB. Urban
Microcell channel Environment achieves maximum
throughput at Eb/No of 10 dB which is greatest from
all channels, providing worst result.
Table 3: Comparative analysis of variation of minimum
throughput among different channel Environment
Channel
Environment
Throughput
(Mbps)
Performance
Rician 637 Best
Nakagami 621 Moderate
Urban Microcell 604 Worst
OFDM system with m=n=4 in SM
It can be clearly seen from the fig. 6 that the
oughput in Rician fading
channel is better than Rayleigh, Nakagami, Sub-
As it can be observed that in Rician fading channel,
maximum throughput is achieved at 4 dB whereas in
Rayleigh fading channel maximum throughput is
achieved at 6 dB. For Nakagami, Sub-Urban
Macrocell, Urban Macrocell and Urban Microcell
channel Environment maximum throughput is
achieved at 8 dB, 8 dB, 9 dB and 10 dB respectively.
ive analysis of Throughput vs Eb/No for
SM system under various Wireless
An enthralling observation in this fig. 6 is that Rician
fading channel achieves maximum throughput at
lowest Eb/No of 4 dB, providing best result. In
Urban Macrocell Environment,
maximum throughput is achieved at 8 dB. Urban
Microcell channel Environment achieves maximum
throughput at Eb/No of 10 dB which is greatest from
tion of minimum
throughput among different channel Environment
Performance
Best
Moderate
Worst
VI. CONCLUSION
In this paper, the Performance analysis in terms of BER
and Throughput in MIMO Spatial Multiplexing integrated
with OFDM system for various Wireless channel models
has been addressed. In SM mode, when number of
subcarriers (N=128) was employed then Rician fading
Environment achieved BER of 10
provides best result. In Nakagami fading Environment
BER of 10-4
is achieved at 6.5 dB which provides
moderate result and Urban Microcell channel
Environment achieved BER of 10
provides poorest result among all channel environments.
A very significant amount of performance improvement
in terms of BER is observed in Rayleigh and Rician
fading channels, when the system embedded with N=128
subcarriers is utilized in low Eb/No region (1
channel conditions deteriorates or in a scenario wh
signal component is bound to experience distortion and
deep fading. In Nakagami, Sub
Macrocell and Urban Microcell channel Environment,
system enabled with N=128 subcarriers provides
significant reduction in BER in medium Eb/
10) dB. It was also found that the minimum throughput
offered by the system changes with variation in the
channel environment in SM mode. It was observed that
by increasing the number of subcarriers (N), Eb/No
decreases at the same Bit Error
REFERENCES
[1] K. Volker. “Wireless Communications over MIMO
Channels Application to CDMA and Multiple
Antenna Systems”, Rostock University, Germany,
John Wiley and Sons Ltd.
[2] E. Biglieri, R. Calderbank, A. Constantinides, A.
Goldsmith, A. Paulraj and H
Communications”. Published in the United States of
America by Cambridge University Press, New York.
[3] R. Suthar, P.C. Bapna and S. Joshi. “A Comparative
Performance Analysis of Spatial Multiplexing and
Transmit Diversity Approaches for
Correlation based Channel”. In: Proceedings of
International Journal of Computer Applications
(0975 – 8887), 2014.
[4] M. Gulzar, R. Nawaz and D. Thapa.
“Implementation of MIMO
WiMAX”. Master’s Thesis, Linnaus University,
Kalmar, 2011.
[5] L. Zheng and D. Tse. “Diversity and Multiplexing: A
Fundamental Tradeoff in Multiple
Channels”. In: Proceedings of IEEE transactions on
Information Theory, Vol. 49, No. 5, May 2003.
ISSN : 2454-1311
Page | 5
CONCLUSION
In this paper, the Performance analysis in terms of BER
Throughput in MIMO Spatial Multiplexing integrated
with OFDM system for various Wireless channel models
has been addressed. In SM mode, when number of
subcarriers (N=128) was employed then Rician fading
Environment achieved BER of 10-4
at 3.3 dB which
ides best result. In Nakagami fading Environment
is achieved at 6.5 dB which provides
moderate result and Urban Microcell channel
Environment achieved BER of 10-4
at 9 dB which
provides poorest result among all channel environments.
ificant amount of performance improvement
in terms of BER is observed in Rayleigh and Rician
fading channels, when the system embedded with N=128
subcarriers is utilized in low Eb/No region (1-5) dB where
channel conditions deteriorates or in a scenario where the
signal component is bound to experience distortion and
deep fading. In Nakagami, Sub-Urban Macrocell, Urban
Macrocell and Urban Microcell channel Environment,
system enabled with N=128 subcarriers provides
significant reduction in BER in medium Eb/No region (5-
10) dB. It was also found that the minimum throughput
offered by the system changes with variation in the
channel environment in SM mode. It was observed that
by increasing the number of subcarriers (N), Eb/No
decreases at the same Bit Error Rate.
REFERENCES
K. Volker. “Wireless Communications over MIMO
Channels Application to CDMA and Multiple
Antenna Systems”, Rostock University, Germany,
John Wiley and Sons Ltd.
E. Biglieri, R. Calderbank, A. Constantinides, A.
Goldsmith, A. Paulraj and H. Poor. “MIMO Wireless
Communications”. Published in the United States of
America by Cambridge University Press, New York.
R. Suthar, P.C. Bapna and S. Joshi. “A Comparative
Performance Analysis of Spatial Multiplexing and
Transmit Diversity Approaches for 2X2 LTE
Correlation based Channel”. In: Proceedings of
nternational Journal of Computer Applications
M. Gulzar, R. Nawaz and D. Thapa.
“Implementation of MIMO-OFDM System for
WiMAX”. Master’s Thesis, Linnaus University,
Diversity and Multiplexing: A
Fundamental Tradeoff in Multiple-Antenna
Channels”. In: Proceedings of IEEE transactions on
Information Theory, Vol. 49, No. 5, May 2003.

ISSN : 2454-1311
www.ijaems.com Page | 6
[6] Agilent Technologies, Inc. 2010. “Agilent MIMO
Channel Modeling and Emulation Test Challenges”
Printed in USA, January 22, 2010, 5989-8973EN
[7] Y. Cho, J. Kim, W. Yang and C. Kang. MIMO-
OFDM Wireless Communications with MATLAB.
Hoboken, NJ: Wiley Press, 2010.

1 ijaems nov-2015-1-a comparative performance analysis of 4x4 mimo-ofdm system using spatial multiplexing under various wireless channels

More Related Content

What's hot (20)

Viewers also liked (15)

Similar to 1 ijaems nov-2015-1-a comparative performance analysis of 4x4 mimo-ofdm system using spatial multiplexing under various wireless channels (20)

Recently uploaded (20)

1 ijaems nov-2015-1-a comparative performance analysis of 4x4 mimo-ofdm system using spatial multiplexing under various wireless channels