sim report

Mid Sweden UniversityThe Department of Information Technology and Media (ITM)Author: Muhammad Ashfaq MalikE-mail address: mama0926, mius0902, [email protected] programme: Simulation of Communication System, 7.5 credit pointsExaminer: Dr. Magnus Eriksson, [email protected]: Dr. Magnus Eriksson, [email protected]: 0 words inclusive of appendicesDate: 2011-02-08

M.Sc. project reportwithin Computer Engineering D, course, 7.5 points

WiMAX MISO & MIMO SIMULINK Model

Muhammad Ashfaq MalikMuhammad Islam

Mudassir Iqbal

mailto:[email protected]



WiMAX - MISO & MIMO SIMULINK Model Muhammad Ashfaq Malik

Acknowledgements / Foreword

2011-02-08

AbstractThe 4G track at among the technologies for mobility, broadband wireless access, and QoS (Quality of Service) is becoming the preferred technology for reliable, flexible, standardized, low cost, very efficient and convenience. The WiMAX (Worldwide interoperability for Microware Access) is an IP based (support to mobility), BWA (Broadband Wireless Access) technology which provide the performance, flexibility, reliability, standardization and Internet access by the cellular technology with long coverage and QoS. The WiMAX is a standard of IEEE 802.16, which is a wireless digital communication system. It is intended for WMAN (Wireless Metropolitan Area Network), which can provide BWA up to 30 miles for fixed station and 3 to 10 for mobile station. WiMAX in LoS (Line of Sight), it have to the air directly from transceiver, operating frequency at weather / atmospheric parameters that can reach longer distance with better signal strength and higher throughput and Non-LoS (Non-Line of Sight) is proportionally converse. The OFDM (Orthogonal Frequency Division Multiplexing) is pillar of WiMAX that multicarrier modulation, ISI (Inter-symbol Interference).

WiMAX vs LTE will play the important role of LTE in the future of wireless cellular network technology that will be providing and ideal backhaul technology for 4G standards. In the eye of WiMAX vs LTE, which will be promising to deliver the internet your cell phone at the speed of your at home broadband internet.

We have calculate the technical point that WiMAX implementation which use the MIMO and MISO transceiver technology improve the reception and allows the data rate as well as transmission power. The WiMAX is almost here the competing technologies, such as HSPA (High-Speed Downlink Packet Access), LTE, IEEE 802.20, IEEE 802.22 are also trying to catch up fast and the next generation WiMAX is already being designed.

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2011-02-08

The most precious goal of the project, we have compared the performance of WiMAX-MISO & MIMO by different SIMULINK models at the various parameters. In both type of transceiver technique, which we have implemented the OFDM with the various value of QPSK (Quadrate Phase Shift Keying), BPSK (Binary Phase Shift Keying) and APSK (Amplitude Phase Shift Keying). After that we have modification of the standard WiMAX-MISO & MIMO SIMULINK model, blocks which as AWGN (Additive white Gaussian noise) fading (Rician & Rayliegh) channels, Modulation and Demodulation. For the purpose of better perfection of the WiMAX-MISO & MIMO SIMULINK model, which we have got the result of the physical media transceiver. The antennas RF (Radio Frequency) has been used the STBC (Space Time Block Code) technique to transceiver the data. Our analytical report will show to us, which types of WiMAX have effective and reliable result at the low BER at the SNR series.

Keywords: WiMAX (Worldwide interoperability for Microware Access), BWA (Broadband Wireless Access), WMAN (Wireless Metropolitan Area Network), OFDM (Orthogonal Frequency Division Multiplexing), ISI (Inter-symbol Interference), WiMAX-MISO & MIMO Simulink model and STBC (Space Time Block Code) technique.

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2011-02-08

Acknowledgements / ForewordAll praises to ALLAH, the most compassionate most merciful.

We wish to express my deepest gratitude Prof. Dr. Magnus

Erikson for his interest and encouragement for this work. We

would like to thank my supervisor Prof. Dr. Magnus Erikson

for his supervisor, support, and invaluable help for this project

and report.

Muhammad Ashfaq Malik

Muhammad Islam

Mudaissir Iqbal

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Table of Contents2011-02-08

Table of ContentsAbstract.............................................................................ii

Acknowledgements / Foreword........................................iii

Terminology / Notation......................................................v

1 Introduction...............................................................11.1 Background and problem motivation.......................11.2 Overall aim / High-level problem statement............21.3 Scope.......................................................................31.4 Concrete and verifiable goals / (Low-level) Problem

statement................................................................31.5 Outline.....................................................................41.6 Contributions...........................................................4

2 Theory / Related work................................................52.1 Definition of terms and abbreviations.....................52.1.1 Example of level 3 heading.............................62.2 To review or to quote...............................................62.3 References and source references..........................62.4 Automatically numbered source references............82.5 Illustrations.............................................................92.6 Mathematical formulas..........................................10

3 Methodology / Model...............................................12

4 Design / Implementation.........................................14

5 Results.....................................................................16

6 Conclusions / Discussion.........................................17

References.......................................................................19

Appendix A: Documentation of own developed program code..........................................................................20

Example of Appendix subheading...........................................20

Appendix B: Mathematical deductions...........................21

Appendix C: User manual................................................22

Appendix D: Result of questionnaire survey...........................23

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Terminology / Acronyms2011-02-08

Terminology / AcronymsSTBC Space-Time Block Coding4G fourth Generation3GPP Third-Generation Partnership ProjectTDD Time Division DuplexingLOS Line Of SightTDM Time Division MultiplexingTDMA Time Division Multiple AccessWAN Wide Area NetworkWAP Wireless Access ProtocolWCDMA

Wideband Code Division Multiple Access

Wi-Fi wireless fidelityWiMAX Worldwide interoperability for Microwave

AccessWLAN Wireless Local Area NetworkWMAN Wireless Metropolitan Area NetworkNLOS Non–Line-Of-SightOFDM Orthogonal Frequency Division MultiplexingOFDMA Orthogonal Frequency Division Multiple

AccessQoS Quality of ServiceIEEE Institute of Electrical and Electronics

EngineersMAC Medium Access Control layerQAM Quadrature Amplitude ModulationBWA Broadband Wireless AccessMISO Multiple-input and Single-output MIMO Multiple-Input and Multiple-OutputGSM Global System for Mobile CommunicationsWMAN Wireless Metropolitan Area NetworkFDD Frequency-Division DuplexingAM Agile Modeling FDM Frequency Division MultiplexingDSL Digital Subscriber LineSISO Single Input, Single OutputSIMO Single Input, Multiple OutputBER Bit Error Rate AWGN Additive White Gaussian NoiseBPSK Binary Phase Shift KeyingSNR Signal-to-Noise RatioQPSK Quadrature Phase Shift KeyingQAM Quadrature Amplitude Modulation

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Terminology / Acronyms2011-02-08

OSTBO Orthogonal Space Time Block CodingFEC Forward Error CorrectionRS Reed-SolomonCC Convolution CodeIFFTFFT Fast Fourier TransformHDL High Density LipidsOSTBC Orthogonal Space Time Block CombinerLTE Long Term Evolution

Mathematical notationSymbol Description

G(x) CRC generator polynomial

kISI Degree of Inter-symbol-interference

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References2011-02-08

1 IntroductionDuring the 1998, the IEEE 802.16 group was developed an air interface standard for wireless broadband. The group was report that the development of a LOS-based point-to-multipoint wireless broadband system operate on the 10 GHz to 66GHz mm wave band. The wireless network standards-based interoperable solution is emerging for wireless broadband which the WiMAX (Worldwide Interoperability for Microwave Access) and compliance with a standard. The WMAN (Wireless Metropolitan Area Network) is the development of WiMAX standards which provide the guaranty of quality of service, security, and mobility. The OFDM (Orthogonal Frequency Division Multiplexing)-based physical layer is used for Non-LoS application with data rate 2 GHz to 11 GHz.

The WiMAX solution as IEEE 802.16-2004 OFDM physical layer SIMULINK model, which is replace all prior WiMAX basics of the fixed application. When the mobile WiMAX, define to it as the IEEE 802.16e-2005 physical SIMULINK model which amendment to the IEEE 802.16-2004 standards of the characteristics add the nomadic and mobility support.

We have studied the multiple collections of IEEE 802.16 standards; there are multiple physical-layer choices and multiple MAC architecture choices. In the order, we have Wireless MAN (Metropolitan Aria Network)-OFDM which based on OFDM-based physical layer and Wireless-OFDMA which based on OFDMA physical layer. Further more over, the WiMAX expand MAC architecture, duplexing and frequency band.

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Table 1. The IEEE 802.16 standards

1.1 Background and problem motivationThe motivation of the project is that to design the smart cellular device that embed the characteristics of power full wireless network qualities. If, we survey the public market there are need to be reduced, and a smaller set of design choices for implementation need to be defined. This requirement it may be by the WiMAX defining a limited number of system profiles and certification profiles which has IEEE 802.16-2004 or IEEE 802.16e-2005 standard to IEEE 802.16-2009, OFDM PHY based. Currently, the WiMAX Forum has two different system profiles: one based on IEEE 802.16-2004, OFDM PHY, called the fixed system profile; the other one based on IEEE 802.16e-2005 scalable OFDMA PHY, called the mobility system profile. More over the, the IEEE 802.16-2009 standard is Vs the prior WiMAX standards. It has to cover the air interference for fixed and mobile broadband wireless access system.

Motivation of the report which has the WiMAX focus on the mobility, broadband wireless access, and QoS (Quality of Ser-vice) is becoming the preferred technology for reliability, flex-ibility, standardized, low cost, and very efficient and conveni-ence. The WiMAX is an IP based (support to mobility), BWA (Broadband Wireless Access) technology which provide the performance, flexibility, reliability, standardization and Inter-net access by the cellular technology with long coverage and QoS. The WiMAX is a standard of IEEE 802.16, which is a wireless digital communication system. It is intended for

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WMAN (Wireless Metropolitan Area Network), which can provide BWA up to 30 miles for fixed station and 3 to 10 for mobile station. WiMAX in LoS (Line of Sight), it have to the air directly from transreceiver, operating frequency at weather / atmospheric parameters that can reach longer distance with better signal strength and higher throughput and Non-LoS (Non-Line of Sight) is proportionally converse. The OFDM (Or-thogonal Frequency Division Multiplexing) is pillar of WiMAX that multicarrier modulation, ISI (Inter-symbol Interference).

1.2 Overall aim / High-level problem statementThe obligation of the project “WiMax (Evolution and Simulator Development)” is Development in MATLAB/ SIMULINK with using the SIMULINK IEEE 802.16-2004 OFDM PHY SIMULINK standard model. After long analytical study, we have to be Implemented of “WiMax (Evolution and Simulator Development) MISO & MIMO” based on OFDM PHY layer, SIMULINK model using the some MATLAB/SIMULIN methods and block functions, which WiMax mode land to find the result that is the more suited for our aim which one we want to develop.

1.3 ScopeThis is the research oriented implementation of the WiMax (MISO & MIMO)-OFDM PHY SIMULINK Model. The IEEE 802.16 group subsequently produced 802.16a, 802.16d and 802.16e, enhancement to the standard, to include Non-LOS and LOS applications in the 2GHz–11GHz band, using an orthogonal frequency division multiplexing (OFDM)-based physical layer. Additions to the MAC layer, such as support for orthogonal frequency division multiple access (OFDMA). All of the research in the field of Wireless network is a backbone of the 4G. It will be more effective, reliable, and perfect for the growth of human beings.

1.4 OutlineChapter 2 will explore to the properties and Implementation of “WiMax (Evolution and Simulator Development)-MISO & MIMO”.Chapter 3 will explain the methodology of the project Chapter 4 will describe the methods of simulink model the project implementation Chapter 5 has the result of the projectFinally, we have the list of reference, where we get the ideas.

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1.5 ContributionsIn this project, we equally participate to complete the whole project as well as its documentation and also do the group study that support to resolve the many problems those we have faced. The strategy of our study, we read the research papers and get idea from web media and also study the books than we get “WiMax (MISO & MIMO)-OFDM PHY Simulink Model”.

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2 Theory / Related workIn the report's theory study, sometimes called Related work, there may be additional facts required for the reader's under-standing of the report. At this point a summary of background material in the area should be provided, i.e. standards, sci-entific articles, books, magazines, documents on the web, technical reports and user manuals. Explain pedagogically with clear examples and many illustrations.

It should be demonstrated that you have an awareness of the context and the background of your work in addition to that carried out by you within the project. Explain the aim of the technology that you describe, and not only how the technology works. For D-level you should display an awareness of the key research within the area, in order to ensure that your work has certain news worthiness. However it is vital that you do not deviate too much from your research problem.

Your assignment is not to write a textbook. It is important to find an appropriate balance between related work and your own results. The theory study should only constitute a minor portion of a thesis.

Instead of “Theory” or “Related work”, the heading may very well be a specific topic, for example “The GSM standard” or ”A survey on the research field of X".

If the theoretical study section is rather brief then it is pos-sible to include it within the Introduction chapter.

2.1 Overview of WiMAXThe overview of WiMAX is a standard-based wireless techno-logy that makes available high throughput broadband connec-tions over long distance. The WiMAX can be used for a num-ber of several distributed or central applications, as well as in-cluding the mile to mile broadband connections, hotspots and high-speed connectivity for business customers. It has to provide WMAN (wireless metropolitan area network) con-nectivity at the data rate up to 70 Mbps and on the average can cover between 5-to-10 km.

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Example of level 3 headingAvoid too many heading levels.

2.2 Standard of WiMAX WiMAX technology is based on the IEEE 802.16 standard, its 2nd name is WMAN (Wireless Metropolitan Area Network). The basic data on IEEE 802.16 Standard is shown below

S.No. Properties 802.16 802.16-2004 802.16e-20051 Status Completed dec,

2001Completed june, 2004

Completed dec, 2005

2 Frequency band

10Gz-66GHz2GHz-11GHz

2GHz-11GHz for fixed

2GHz-6GHz for mobile app.

3 Application Fixed LOS Fixed Non-LOS Fixed and Mobile Non-LoS

4 MAC architecture

Point to Multipoint mesh



5 Transmission Scheme

Singel carrier only Singel carrier256 OFDMor 2,048OFDM

Single carrier, 256 OFDM or scalable OFDM with128, 512, 1,024 or 2,048 sub carrier

6 Gross data rate 32Mbps-134.4Mbps

1Mbps-75Mbps 1Mbps-75Mbps

7 Multiplexing Duplexing

Burst TDM/TDMA Burst TDM/TDMA/ OFDM

Burst TDM/TDMA/ OFDMA

8 Channel bandwidths

TDD and FDD TDD and FDD TDD and FDD

9 Air-Interface designation

WirelessMAN-SC WirelessMAN-SCaWirelessMAN-OFDMWirelessMAN-OFDMA

WirelessMAN-SCaWirelessMAN-OFDMWirelessMAN-OFDMA

10 WiMAX implementation

None 256 – OFDM as Fixed WiMAX

Scable OFDMA as Mobile WiMAX

Table 2.1: WiMAX Standard

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2.3 Orthogonal Frequency Division MultiplexingOFDM (Orthogonal frequency division multiplexing) is a FDM (frequency division multiplexing) modulations technique for transmitting the large amounts of digital data over a radio wave, which is divided into several parallel lower bit rates into high bit rate data stream flew, and operation in different modulation stream and sub carriers. Therefore, high data rate system of small symbol duration is inversely proportional to data rate, which is split into many parallel streams which increases the flow of data symbols for each data. More over OFDM works by splitting the system into multiple smaller sub-signals on a different frequency that are transmitted to the receiver while receiving the signal continuously. OFDM reduces the large amount of crosstalk in signal broadcast 802.11a, 802.16 and WiMAX technologies which used in OFDM.

Fig.2.1 Orthogonal Frequency Division Multiplexing

Principles of OFDMOFDM is also a block transmission method. In this technique the complex-valued data symbols adjust a large number of strongly grouped carrier waveforms. The major benefit of this concept in a radio environment is that each of the data streams experiences an almost flat fading channel.

Signal characteristics OFDM with a cyclic prefix Channel noise and Doppler spread Design of OFDM signals Coding

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2.4 Orthogonal Frequency Division Multiple AccessOFDM is a modulation technique but a signal access approach and created many independent users can be used by different data streams. The earlier OFDM systems such as DSL, 802.11 / G and 802.16/WiMAX earlier versions, use the single-user OFDM. In this scheme all the sub carriers are used by a single user at a time. For example, in 802.11a/g, collocate many users which are dividing the 20MHz bandwidth by transmitting at different times after contending for the channel. WiMAX (802.16e-2005) obtain a different approach, known as OFDMA (orthogonal frequency division multiple access), in which users distribute sub carriers and time slots. OFDMA technique is more costly as compare to OFDM, such as overhead in both directions: First transmitter which needs the channel information for its users, and the second one is receiver which needs to know sub carriers it has been assigned.

Figure 2.2: orthogonal frequency division multiple accesses.

Advantages of OFDMAAfter the large study, we have observed there are following advantage of OFDMA.

OFDMA basically the mixture of FDMA and TDMA. OFDMA is a flexible multiple-access technique. Using the same power the OFDMA approve the same

data rate to be sent. In OFDMA Users are dynamically collected sub carriers

(FDMA) in different time slots (TDMA). It is possible to minimize interface from neighbouring

cell by using different carrier in a cellular system. Major advantage of OFDMA is reduce the transmit

power and to solve the problem of peak-to-average-power ratio.

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Fig. 2.3: In OFDMA, the base station allocates to each user

Fig. 2.4: OFDM with 256 and OFDMA with only 64 of the 256 sub carriers

OFDMA ProtocolsThe main basic protocols of OFDMA are described in the following Mainer as

Sub-channelization Mapping messages Ranging

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The difference and the benefit of OFDM & OFDMAThe main benefits and differences have been described as following

One of the main differences is that IEEE 802.16d uses OFDM.

And IEEE 802.16e (mobile) uses OFDMA. OFDM is better suited to fixed application and less

complex than OFDMA. OFDMA is more flexible due to managing different user

device. The operator is easier to managing the bandwidth and

transmits power.

Fig. 2.5: OFDM AND OFDMA

2.5 Line Of SightLine of sight (LOS) is a fixed dish antenna point’s which is straight at the WiMax tower from a root top. Its frequency rang normally 66 GHz and radius is 30-mile.

2.6 Non-Line of Sight

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Non-line of sight (Non-LOS) is a small antenna on computer which is connects to the tower and it is used to explain the radio transmission which across partially obstructed a path between the location of the signal transreceiver. Many kinds of radio transmission which is depend to unstable degrees, on line of sight between the transreceiver. Normally the common conditions which are include buildings, tress, hill, mountain and other natural object. NLOS is normally less refereed to as loose line of sight. Its frequency range is normally 2 GHz to 11 GHz and radius is 4 to 6 mile

2.7 MIMO (Multiple-Input and Multiple-Output)We can improve and make strong communication from end to end wireless communication by using the multiple power antennas mechanism. We have make logical design, which are 1 to 1, 1 to many, many to 1 and many to many. In this, we have discussed about the use of antennas MIMO. In addition of radio frequency, multiple-input and multiple-output, is used to improve the communication performance between multiple antennas at both the transceiver. MIMO can be divided into three main categories which is point out in given below.

Preceding Spatial multiplexing Diversity coding

Further more, we have explain of MIMO channel (many to many) by using the mathematical terms as, in a 2×2 MIMO channel, probable usage of the available 2 transmit antennas can be as follows

Consider that we have a transmission sequence, for ex-ample

In normal transmission, we will be sending in the first time slot, in the second time slot, and so on.

However, as we now have 2 transmit antennas, we may group the symbols into groups of two. In the first time slot, send and from the first and second antenna. In second time slot, send and from the first and second antenna, send and in the third time slot and so on.

Notice that as we are grouping two symbols and sending

them in one time slot, we need only time slots to com-plete the transmission – data rate will be doubled.

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This forms the simple explanation of a probable MIMO transmission scheme with 2 transmit antennas and 2 re-ceive antennas.AWGN & Receiver Diversity

WiMAX with SISO, MISO, SIMO and MIMO is a series of in-crease the Antennas with the method Xi=x1+x2+………….+xn. Where Xi is the antennas i=1,2,3,……..n. this design strategy is to make a strong multiple antenna’s at the transceiver improves the bit error rate (BER) performance. In this technique, let us describe to understand the BER improvement with (mathematical way to) receive diver-sity. We are just getting started, let us limit ourselves to additive white Gaussian noise (AWGN) channel (i.e assume that the channel gains are unity).

Single receive antenna case Let us start with the mathematical prove that there is one

transmit antenna, sending signals with energy and one receive antenna.

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Since, we are taking only BPSK modulation, and the sig-nals which are sent out are either or .

Let assume that there will be a single receive antenna hav-ing a thermal noise (either Rician or Rayliegh fading)

AWGN with MEAN and VARIANCE

The probability for the density function of noise is,

The received signal equation is, , where

is the received symbol, Is the transmitted symbol (taking values ’s and

’s) and is the Additive White Gaussian Noise (AWGN).

In the scenario, BER for BPSK modulation in AWGN, that

probability of bit error is,

Receive diversity with two antennas

Now, we consider with the two transceiver anten-nas each one have thermal noise (AWGN) with

MEAN and VARIANCE and the noise on each antenna is independent from each other, and trans-mitter is sending symbols with energy

The received signal is, , where , are the received symbols from receive antenna 1, 2 respectively,

is the transmitted symbol (taking values ’s and’s) and , is the Additive White Gaussian Noise

(AWGN) on receive antenna 1, 2 respectively

For simplicity, let us assume that the signal was

transmitted. At the receiver, we now have

and

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To decode, the simplistic is to take the mean of , and

perform hard decision decoding, and if

implies the transmitted bit is 1 and implies trans-mitted bit is 0.

Now, let us find out if there is any receive diversity gain by performing this averaging. Splitting into signal term

and noise term

In the discussion perspective, we have sum of Gaussian random variables, if is a Gaussian random variable

with mean , variance and is another indepen-dent Gaussian random variable with mean , vari-

ance , then is another Gaussian random variable

with mean , variance Furher, from the dis-cussion on functions of Gaussian random variables, if is a Gaussian random variable with mean , vari-

ance , then is another Gaussian random vari-

able with mean , variance

Using the above two equations, the noise term is an-other Gaussian random variable with mean and v ri-

ance

When compared with the single antenna case, we can see the variance of the noise term is scaled by a factor of 2. This implies that the effective bit energy to noise ratio in a two receive antenna case is twice the bit energy to noise

ratio for single antenna So, the bit error

probability for two receive antenna is, . Expressing in decibels, with two receive antennas, we need

only lower bit energy .

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Receive diversity with N receive antenna

With a general N transceiver antenna, the received symbol is,

, where , ,… are the received symbols from receive antenna 1, 2 respectively, is the transmitted sym-bol (taking values ’s and ’s) and

, ,… is the Additive White Gaussian Noise (AWGN) on receive antenna 1, 2,… N respectively.

For demodulation, we compute which is the mean of all the N

received symbols, and if implies the transmitted bit is 1

and implies transmitted bit is 0.

The variance of the noise term is .

Effective bit energy to noise ratio in an N receive antenna case is N times the bit energy to noise ratio for single an-tenna.

.

So the bit error probability for N receive antenna is,

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3 Methodology / ModelWiMAX is the technology brand name for the implementation of the standard IEEE 802.16, which specifies the air inter-face at the PHY (Physical layer) and at the MAC (Medium Ac-cess Control layer). As we specifying the support of various channels, bandwidths, adaptive modulation and MATLAB cod-ing is a pillar of our project goal. It is specifies the support for MISO & MIMO antennas to provide good Non-line-of-sight (NLOS) characteristics. The WiMAX MISO model use the standard parameter, on the other side for WiMAX MIMO we have write a code, which can take the dynamic parameter of the MIMO model that dynamic parameter automatically select the some our required parameter values, which are written in the following code as Channel Bandwidth, delay spread spec-trum, Channel SNR, Modulation Scheme.//code.m file

%simulate the model for different SNR values%close the model if it is openclearclcBW=input('Required channel bandwidth in MHz(max 20 MHz)=');disp('choose cyclic prefix to overcome delays spreads')disp(',1/4 for longest delay spread ,1/8 for long delay spreads ,')disp('1/16 for short delays spreads ,1/32 for very small delay spread channels')G=input('= ');channels=[1.75 1.5 1.25 2.75 2.0];oversampling=[8/7 86/75 144/125 316/275 57/50 8/7];for i=1:5 y(i)=rem(BW,channels(i)); if y(i)==0 n=oversampling(i); endendy=(y(1))*(y(2))*(y(3))*(y(4))*(y(5));if y~=0 n=8/7;endif ((G~=1/4)&(G~=1/8)&(G~=1/16)&(G~=1/32)) error('you have choosed a guard period thats not valid in the ieee 802.16')endNused=200; Nfft=256;fs=(floor((n*BW*1e6)/8000))*8000; %sampling freqencyfreqspacing= fs/Nfft; %freqency spacingTb= 1/freqspacing; %usfel symbol timeTg= G*Tb ;%Guard timeTs=Tb+Tg ;%symbol time samplingttime= Tb/Nfft; %adaptive encoding and decoding depending on the channel SNR

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genpoly=gf(1,8);for idx=0:15 genpoly=conv(genpoly,[1 gf(2,8)^idx]);endprimepoly=[1 0 0 0 1 1 1 0 1];convvec=poly2trellis(7,[171,133]);cSNR=input('Enter the channel SNR in dB(it should be above 6.4 dB)=');if cSNR<6.4 error('not a valid channel for transmission ,use another channel with better SNR')end%BPSK 1/2if (6.4<=cSNR&cSNR<9.4) inputsize=88; seqafterrand=inputsize+8; shortening=[1:12]; shorteningRx=[1:11]; punvec=reshape([1 , 1],2,1);%convolutional of rate 1/2 Ncbps=192;%selctor of RS 12*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=[+1 -1]; Iy=[0 0]; qamconst=complex(Ry,Iy); qamconst=qamconst(:); bitspersymbol=1; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate=1/2; disp('Modulation scheme of BPSK with Coding rate 1/2 is chosen');elseif (9.4<=cSNR&cSNR<11.2) inputsize=184; seqafterrand=inputsize+8; shortening=[1:32]; shorteningRx=[1:23]; punvec=reshape([1 0 , 1 1],4,1);%convolutional of rate 2/3 Ncbps=384; %selctor of RS 48*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(2,1)*[+1 -1]; Iy=([+1 -1]')*ones(1,2); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(2); bitspersymbol=2; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate=1/2; disp('Modulation scheme of QPSK with Coding rate 1/2 is chosen');elseif (11.2<=cSNR&cSNR<16.4) inputsize=280; seqafterrand=inputsize+8; shortening=[1:40]; shorteningRx=[1:35]; punvec=reshape([1 0 1 0 1, 1 1 0 1 0],10,1);%convolutional of rate 5/6 Ncbps=384; %selctor of RS 48*8

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k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(2,1)*[+1 -1]; Iy=([+1 -1]')*ones(1,2); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(2); bitspersymbol=2; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate=3/4; disp('Modulation scheme of QPSK with Coding rate 3/4 is chosen');elseif (16.4<=cSNR&cSNR<18.2) inputsize=376; seqafterrand=inputsize+8; shortening=[1:64]; shorteningRx=[1:47]; punvec=reshape([1 0 , 1 1],4,1);%convolutional of rate 2/3 Ncbps=768; %selctor of RS 96*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(4,1)*[+1 +3 -1 -3]; Iy=([+1 +3 -3 -1]')*ones(1,4); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(10); bitspersymbol=4; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate= 1/2; disp('Modulation scheme of 16-QAM with Coding rate 1/2 is chosen');elseif (18.2<=cSNR&cSNR<22.7) inputsize=568; seqafterrand=inputsize+8; shortening=[1:80]; shorteningRx=[1:71]; punvec=reshape([1 0 1 0 1, 1 1 0 1 0],10,1);%convolutional of rate 5/6 Ncbps=768; %selctor of RS 96*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(4,1)*[+1 +3 -1 -3]; Iy=([+1 +3 -3 -1]')*ones(1,4); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(10); bitspersymbol=4; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate= 3/4; disp('Modulation scheme of 16-QAM with Coding rate 3/4 is chosen');elseif (22.7<=cSNR&cSNR<24.4) inputsize=760; seqafterrand=inputsize+8; shortening=[1:108];

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shorteningRx=[1:95]; punvec=reshape([1 0 1 , 1 1 0 ],6,1);%convolutional of rate3/4 Ncbps=1152; %selctor of RS 144*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(8,1)*[+3 +1 +5 +7 -3 -1 -5 -7 ]; Iy=([+3 +1 +5 +7 -3 -1 -5 -7 ]')*ones(1,8); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(42); bitspersymbol=6; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate= 2/3; disp('Modulation scheme of 64-QAM with Coding rate 2/3 is chosen');elseif 24.4<=cSNR inputsize=856; seqafterrand=inputsize+8; shortening=[1:120]; shorteningRx=[1:107]; punvec=reshape([1 0 1 0 1, 1 1 0 1 0],10,1);%convolutional of rate 5/6 Ncbps=1152; %selctor of RS 144*8 k=0:Ncbps-1; mk=(Ncbps/12 )*mod(k,12)+floor(k/12); s=ceil(Ncbps/2); jk=s*floor(mk/s)+mod(mk+Ncbps-floor(12*mk/Ncbps),s); [x,int_idx]=sort(jk); Ry=ones(8,1)*[+3 +1 +5 +7 -3 -1 -5 -7 ]; Iy=([+3 +1 +5 +7 -3 -1 -5 -7 ]')*ones(1,8); qamconst=complex(Ry,Iy); qamconst=qamconst(:)/sqrt(42); bitspersymbol=6; CPsel=[(256-G*256+1):256 1:256]; CPremove=[(256*G+1):(256+G*256)]; coderate= 3/4; disp('Modulation scheme of 64-QAM with Coding rate 3/4 is chosen');endchoice=input('Enter 1 for inculding mimo in the system and 0 otherwise');if choice==1 MimoOFDM=-10; Pulse=2; delayswitch=2; delayBER=2*inputsize;else MimoOFDM=10; Pulse=1; delayswitch=0; delayBER=0;end

Further In this, we have implement and analysis with different angles, which are describe in this chapter. In this, we go be-hind the strategy is, Bit Error Rates are compared against the Signal to Noise Ratio values. So, the analytic view of the MISO & MIMO on the several changing the Signal to Noise Ratio of the AWGN fading channels (Rician & Rayleigh) of the models

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and recording the BER values by sending the values to the workspace instead of port. A small script is written to set the SNR value each time and simulate the model for the specified SNR values.//matlabcode1.m file

// in this code we call the code.m file and wimac_ashfaqq.mdl file%bdclose('wimax_Ashfaq.mdl');clear all;clc;run code;open wimax_Ashfaq1.mdl; cSNR = 1:1:30;BitErrorRate = zeros(length(cSNR));ber = zeros(length(cSNR)); %set the model parametersfor i = 1:1:length(cSNR) set_param('wimax_Ashfaq1/AWGN Channel3','SNRdB', num2str(i)); set_param('wimax_Ashfaq1/AWGN Channel1','SNRdB', num2str(i)); %run the simulation simout = sim('wimax_Ashfaq1'); meanber = BER.signals.values(end, 1); ber(i) = meanber(1);end %save the output in *.mat filesave ashfaq1.mat;

//matlabcode0.m file

//in this code we call the code.m file and wimac_ashfaqq.mdl file%bdclose('wimax_Ashfaq.mdl');clear all;clc;run code;open wimax_Ashfaq0.mdl; cSNR = 1:1:30;BitErrorRate = zeros(length(cSNR));ber = zeros(length(cSNR)); %set the model parametersfor i = 1:1:length(cSNR) set_param('wimax_Ashfaq0/AWGN Channel3','SNRdB', num2str(i)); %run the simulation simout = sim('wimax_Ashfaq0'); meanber = BER.signals.values(end, 1);

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ber(i) = meanber(1);end %save the output in *.mat filesave ashfaq0.mat;

//Plot the single graph%plot the graph by loading the *.mat fileclear all;clc;load ashfaq1.matNR = 1:1:30;figure(1); semilogy(NR,ber,'g');axis([1 30 .11 1])hold on;% for y=1:1:length(NR)% %semilogy(SNR(y),ber(y),'b*');% semilogy(NR(y),ber(y),'g*');% hold on;% endxlabel('SNR');ylabel('BER');grid on;

//Plot the combine graph

%plot the graph by loading the *.mat fileload ashfaq0.matNR = 1:1:30;figure(2);semilogy(NR,ber,'b');axis([1 30 .0001 1])hold on; xlabel('SNR');ylabel('BER');grid on; load ashfaq1.matNR = 1:1:30;semilogy(NR,ber,'g');xlabel('SNR');ylabel('BER');grid on;

The Multipath Rician & Rayleigh Fading Channel block implements a base-band simulation model of a multipath Rician & Rayleigh fading propagation channel. We have use “Rician & Rayleigh Fading Channel block” to WiMAX simulink MISO & MIMO model. This block accepts a scalar value or column vector input signal. The block inherits sample time from the input sig-nal. The input signal must have a discrete sample time greater than 0. Relative motion between the transmitter and receiver causes Doppler shifts in the signal frequency. In this scenario, we are specifying the Doppler spectrum of the Ri-

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cian & Rayleigh process using the Doppler spectrum type parameter, each of which may have differing lengths and associated time delays.

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4 Design / Implementation

4.1 WiMAX with MISO & MIMOWe have implement WiMAX with MISO (Multiple-input and Single-output) and MIMO (Multiple-input and Multiple-output). The both MATLAB/simulink model are shown below simultaneously. In first part, we have design and implement the WiMAX-MISO after that WiMAX (MIMO) as following

4.1.1 IEEE 802.16-2004 OFDM PHY link, including Space-Time Block Coding (WiMAX-MISO)This model shows the main components of the WMAN 802.16-2004 OFDM physical layer using with STBC. We have ex-plained the main parts of the model, which have discussed in later. Some of MISO and MIMO have the common model block that block we have explain together. In both model we have use the OSTBO (Orthogonal Space Time Block Coding) techno-logy. The WiMAX-MISO, we have taken the standard model from MATLAB/ Simulink model and modify it, as shown in the following.

Fig.4.1: IEEE 802.16-2004 OFDM PHY link

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We have the common part of the both model, which tasks per-formed in the communication system models included as

Both models are beginning with the generation of random bit data that models a downlink burst consisting of an integer number of OFDM symbols. After that we have use the Forward Error Correction (FEC), consisting of a Reed-Solomon (RS) outer code con-catenated with a rate-compatible inner convolution code (CC). Data interleaving. Modulation, using one of the BPSK, QPSK, 16-QAM or 64-QAM constellations specified. Orthogonal Frequency Division Multiplexed (OFDM) transmission using 192 sub-carriers, 8 pilots, 256-point FFTs, and a variable cyclic prefix length. In the STBC (Space-Time Block Coding) using an Alamouti code. This implementation uses the OSTBC En-coder and Combiner blocks in the Communications Block-set™. A single OFDM symbol length preamble that is used as the burst preamble. For the optional STBC model, both antennas transmit the single symbol preamble. An optional memoryless nonlinearity that can be driven at several backoff levels. An optional digital pre-distortion capability that cor-rects for the nonlinearity. A Multiple-Input-Single-Output (MISO) fading chan-nel with AWGN for the STBC model. OFDM receiver that includes channel estimation us-ing the inserted preambles.

4.1.2 IEEE 802.16e-2005 OFDM PHY link, (WiMAX-MIMO) with two fading channelIn the designing of the following model, we have followed the standard model of IEEE 802.16e-2005 OFDM PHY link with OSTBC. We have explained the main parts of the model in previous section and some are additional which use in WiMAX-MIMO model have explained in this portion. We have design two type of model in the scenario of WiMAX-MIMO. In first model, we use two fading channel with each antenna and in second model, we use one fading channel, before it we combine the both transmitted data.

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Fig4.2: IEEE 802.16e-2005 OFDM PHY link, (WiMAX-MIMO) with two fading channel

4.1.3 IEEE 802.16e-2005 OFDM PHY link, (WiMAX-MIMO) with single fading channelIn this model, we have combine the both antenna data and than apply the fading channel, which have shown in the following. In this model, we also use the standard model of IEEE 802.16e-2005 OFDM PHY link with OSTBC.

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Fig.4.3: IEEE 802.16e-2005 OFDM PHY link, (WiMAX-MIMO) with single fading channel

4.2 WiMAX (MISO & MIMO) ComponentsThe models contains the following modules which are used in the IEEE 802.16-2004 and IEEE 802.16e-2005, physical layer MATLAB/simulation model. Each module consists of many sub modules as over in the following etc.

4.2.1 Bernoulli Binary generatorThe model generates the random data using the Bernoulli Binary generator which generates data bits by uniform distribution. The random source generates a continuous waveform which is sampled to convert to frames.

Fig.4.4: Bernoulli Binary Generator

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4.2.2 Forward Error Correction (FEC) and Modulator BankThis module consists of the Forward Error Correction sub module and the other Modulator sub modules as shown below. Forward Error correction is used to correct errors in bits at the receiver side without the need for re-transmission.

Fig.4.5. Modulation Bank and FECAs the model uses a rate adaptive scheme all the modulation schemes are implemented and the used depending on the SNR value. The Forward Error correction code is a Reed Solomon code outer concatenated with the convolution code

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4.2.3 IFFT packagingThis module is used to break the complex waves into multiple simple waves that can be easily transmitted. It converts the input frequency domain signal into Time domain signal as shown in the following diagram.

Fig.4.6: IFFT Input Packing

4.2.4 Space Time Diversity EncoderThis module contains the blocks that are used for space time diversity coding which is used to reduce the effect to noise and increase the bandwidth by reducing the Bit Error Rate. The module and its code is shown below

Fig.4.7: Space-Time Block Encoder// code for data divided into two parts (signal per antenna)

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function [ant1, ant2] = stbcenc(u)% STBCENC Space-Time Block Encoder% Outputs the Space-Time block encoded signal per antenna. N = 2;ant1 = complex(zeros(size(u)));ant2 = ant1; % Alamouti Space-Time Block Encoder, G2, full rate% G2 = [s0 s1; -s1* s0*]for i = 1:size(u,2)/2 s0 = u(:, 2*i-1); s1 = u(:, 2*i); ant1(:, [2*i-1 2*i]) = [s0 -conj(s1)]; ant2(:, [2*i-1 2*i]) = [s1 conj(s0)];end

4.2.5 OFDM TransmitterThis model implements a simple OFDM transmitter and re-ceiver. The OFDM receiver part contains a 512-point to con-vert signal back to the frequency domain. There are two FFT implementations in this model: The Simulink SP Blockset FFT block is the FFT block in Signal Processing Block set li-brary. It calculates a 512-point vector input each sample and works at a sample rate of 512.The HDL Streaming FFT block is a serialized, streaming I/O FFT block. This implementation accepts streaming complex input data and generates streaming complex results continuously after the initial pipelining latency.

Fig.4.8: OFDM Transmitter

4.2.6 MISO Fading Channel with AWGN

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The STBC link model uses a MISO fading channel to model a two transmitter, one receiver (2x1) system. The fading parameters are identical for the two links. The Space-Time Diversity Combiner block uses the channel estimates for each link and combines the received signals. The combining operation performs simple linear processing using the orthogonal signaling employed by the encoder.

Fig.4.8: MISO Fading Channel with AWGN

4.2.7 Rician FadingThe Multipath Rician Fading Channel block implements a baseband simulation of a multipath Rician fading propagation channel. You can use this block to model mobile wireless communication systems when the transmitted signal can travel to the receiver along a dominant line-of-sight or direct path.

Fig.4.9: Rician Fading

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4.2.8 AWGN ChannelThe AWGN Channel block adds white Gaussian noise to a real or complex input signal. When the input signal is real, this block is adds real Gaussian noise and produces a real output signal. When the input signal is complex, this block adds complex Gaussian noise and produces a complex output signal. This block inherits its sample time from the input signal.

Fig.4.10: AWGN Channel

4.2.9 AWGN blockThis block uses the Signal Processing Blockset Random Source block to generate the noise. Random numbers are generated using the Ziggurat method. The Initial seed parameter in this block initializes the noise generator. Initial seed can be either a scalar or a vector whose length matches the number of channels in the input signal.

Fig.4.11: AWGN Block

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This block accepts a scalar-valued, vector, or matrix input signal with a data type of type single or double. The output signal inherits port data types from the signals that drive the block.

4.2.10 OFDM ReceiverThe serialize block generates the streaming input data for the FFT block. The original 512-point vector input is converted to one data point per sample by the Unbuffer block. This FFT block implements the Decimation-in-Time FFT algorithm which requires bit reverse-ordered input data. So the natural-ordered input data will pass through the stage Start_BitReverse in the beginning.

Fig.4.12: OFDM Receiver

4.2.11 Space Time Diversity CombinerThe Space-Time Diversity Combiner block uses the channel estimates for each link and combines the received signals

Fig.4.13: Space-Time Diversity Combiner

4.2.12 Orthogonal Space Time Block Combiner (OSTC)The OSTBC Combiner block combines the input signal (from all of the receive antennas) and the channel estimate signal to extract the soft information of the symbols encoded by an OSTBC. The input channel estimate may not be constant during each codeword block transmission and the combining algorithm uses only the estimate for the first symbol period per codeword block. A symbol demodulator or decoder would follow the Combiner block in a MIMO communications system.

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Fig.4.14: AWGN Channel

4.2.13 Extract Data CarrierWe can "split up" the received signal by Separate Data & Pilots block, in this block, terminate the Pilots data and real data forward it, to the next portion.

Fig.4.15: Extract Data Carrier

4.2.14 Demodulator and FCE BankIt is inverse of “Modulation and FCE bank” and shown in the following diagram. The explanation have been explained in the previous parts

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Fig.4.16: Demodulator and FCE Bank

4.2.15 ALAMOUTI Transmitter and ReceiverThis demo introduces Multiple-Input-Multiple-Output (MIMO) systems, which use multiple antennas at the transmitter and receiver ends of a wireless communication system. MIMO systems are increasingly being adopted in communication systems for the potential gains in capacity they realize when using multiple antennas. Multiple antennas use the spatial dimension in addition to the time and frequency ones, without changing the bandwidth requirements of the system.

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This demo introduces Multiple-Input-Multiple-Output (MIMO) systems, which use multiple antennas at the transmitter and receiver ends of a wireless communication system. MIMO systems are increasingly being adopted in communication systems for the potential gains in capacity they realize when using multiple antennas. Multiple antennas use the spatial dimension in addition to the time and frequency ones, without changing the bandwidth requirements of the system.

Fig.4.17: Alamouti Transmitter

Fig.4.18: Alamouti Receiver

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4.2.16 Bit Error Rate CalculationThe Error Rate Calculation block compares input data from a transmitter with input data from a receiver. It calculates the error rate as a running statistic, by dividing the total number of unequal pairs of data elements by the total number of input data elements from one source. Use this block diagram to compute either symbol or bit error rate, because it does not consider the magnitude of the difference between input data elements. If the inputs are bits, then the block computes the bit error rate. If the inputs are symbols, then it computes the symbol error rate.

Fig.4.19: Bit Error Rate Calculation

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5 ResultsThe results of the WiMAX (MISO & MIMO)-OFDM PHY SIM-ULINK Model are plotting with the different perspective and parameter values.

5.1 The standard WiMAX MISO with BER vs. SNRThe plots that are generated from the recorded BER for vari-ous SNR values for model with MISO channel with OSTBC are shown below

Fig.5.1: The standard WiMAX MISO with BER vs. SNR The more description of the shown plotted graph as BER de-creases with the increase in SNR values. The BER is inversely proportional to the SNR with a constant factor and a constant Doppler shift. The BER is decreasing with the increase in SNR values as the modulation scheme changes with the increase in SNR from BPSK to 64-QAM. The BER is plotted in a logarith-mic scale. The unit of SNR is in DeciBels.

5.2 WiMAX MISO BER of QPSK Modulation with Rayliegh fading

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We have took the following graph after the changing in the WiMAX MISO in the block of modulation and AWGN then the performance measurement of high data rate modulation schemes at those channels which are subjected to Multipath Rayleigh Fading and Additive White Gaussian Noise (AWGN) with the 64QAM & QPSK, which are shown bellow

5.3 WiMAX MISO BER of QPSK Modulation with Ri-cian fading

We have took the following graph after the changing in the WiMAX MISO in the block of modulation and AWGN then the performance measurement of high data rate modulation schemes at those channels which are subjected to Multipath Rician Fading and Additive White Gaussian Noise (AWGN) with the 64QAM & QPSK, which are shown bellow

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5.4 WiMAX MIMO BER of QPSK Modulation with Rayliegh fading

In the WiMAX MIMO SIMULINK Model, we have plots that are generated from the recorded BER for various SNR values for model with Alamouti transceiver MIMO channel with OSTBC and Rayliegh fading and AWGN are shown below

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Fig.5.6: WiMAX MIMO BER of QPSK Modulation with Rayliegh fading

5.5 WiMAX MIMO BER of QPSK Modulation with Ri-cian fading

In the WiMAX MIMO SIMULINK Model, we have plots that are generated from the recorded BER for various SNR values for model with Alamouti transceiver MIMO channel with OSTBC and Rician fading and AWGN are shown below

Fig.5.6: WiMAX MIMO BER of QPSK Modulation with Rician fading

5.6 WiMAX MIMO BER of QPSK Modulation with Ri-cian & Rayliegh fading

In the WiMAX MIMO SIMULINK Model, we have plots that are generated from the recorded BER for various SNR values for model with Alamouti transceiver MIMO channel with OSTBC, Rayliegh & Rician fading and AWGN are shown below

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Fig.5.6: WiMAX MIMO BER of QPSK Modulation with Rayliegh & Rician fading

The above plotted graph shows the comparison of WiMAX MIMO with Rayliegh and Rician fading with the different value of SNR. The blue lines indicate the MIMO with Rician fading for the model with the AWGN channels. The red line indicates the Rayliegh for the model with the AWGN channels. As, the models implement an adaptive rate scheme of BER decreases with increases in SNR at the QPSK of the 64QAM.

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6 Conclusions / DiscussionThe Wireless Communication System WiMAX is a top level MATRLAB/SIMULINK model with all Wireless Communication system details has been implemented for analysis purpose, which one scenario is perform the perfection. There are a lot of developments going on in this area and it is still in nascent stages. With enhancements and improved physical layer and MAC layer model design the IEEE could bring a new standard which possibly could meet all the specification of LTE. The model used for study was IEEE802.16-2004 and IEEE802.16e-2005 which are much older and contains the basic details for the Air Interface for Fixed/mobile Wireless Metropolitan Area Networks (WMAN). This research report has focused on channel estimation MISO & MIMO with different interpolation approaches for fixed/mobile OFDM system with parameters from WiMAX standards. The AWGN fading channel (Rician & Rayliegh), which has the Doppler shift, had a greater impact on the relative performance between the different channel estimators and interpolation approaches. There are two main tasks: One of them is analyze to compare the performance on the 64-QAM of MISO & MIMO on the SNR db values then we get the BER db values. In the result chapter, there are shows the graph, MIMO performance perfact then MISO on the different BPSK. The second part, we have test the MIMO SIMULINK model by using the different AWGN fading channel (Rician & Rayliegh) at the most interesting properties that were discovered is the big impact shown in the result chapter, there is Our results indicate that a performance degradation can be expected in such an environment relative to Rayleigh/Rician fading, however, the degradation is significant only at very low values average SNR. At average SNR levels that provide 10 percent outage or better the simpler analytic model for Rayleigh fading may be used if the mean value of the desired signal is high relative to the required minimum signal level at the receiver.

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Finally, the SIMULINK models with MISO & MIMO channel has been studied and simulated for varying Signal to Noise Ratio. The different modulation schemes that were used in the models contribute to a better throughput. The models have been compared with the models of different properties with the multiple transmit antennas. The SIMULINK model with multiple transmit antennas is found to be less prone to interference and noise than the model without MIMO channel. So further is that the Doppler shift effect has been reduced by adding multiple antennas. The model has been modified and improved for the next specification of IEEE802.16e for mobile Wireless Broadband by using the MIMO.

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References[1] www.wikipedia.org

[2] www.google.com

[3] http://dspace.bracu.ac.bd/bitstream/ 10361/192/1/Study%20of%20WiMAX%20Simulation.pdf

[4] http://www.conniq.com

[5] http://www.wimax.com

[6] http://www.tutorialspoint.com

[7] http://www.dsplog.com/2008/08/19/ receive-diversity-in-awgn/

[8] http://www.dsplog.com/2007/08/05/bit- error-probability-for-bpsk-modulation/

[9] http://d.yimg.com/kq/groups/ 21439157/797502892/name/WIMAX.pdf

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http://d.yimg.com/kq/groups/21439157/797502892/name/WIMAX.pdf

http://d.yimg.com/kq/groups/21439157/797502892/name/WIMAX.pdf

http://www.dsplog.com/2007/08/05/bit-error-probability-for-bpsk-modulation/

http://www.dsplog.com/2007/08/05/bit-error-probability-for-bpsk-modulation/

http://www.dsplog.com/2008/08/19/receive-diversity-in-awgn/

http://www.dsplog.com/2008/08/19/receive-diversity-in-awgn/

http://www.tutorialspoint.com/

http://www.wimax.com/

http://www.conniq.com/

http://dspace.bracu.ac.bd/bitstream/10361/192/1/Study%20of%20WiMAX%20Simulation.pdf

http://dspace.bracu.ac.bd/bitstream/10361/192/1/Study%20of%20WiMAX%20Simulation.pdf

http://www.google.com/

http://www.wikipedia.org/


Appendix D: Result of questionnaire survey

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Appendix A: Documentation of own developed program codeExample of Appendix subheading

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Appendix B: Mathematical deductions

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Appendix C: User manual

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sim report

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