Ofdm Used with Matlab

The WiMAX technology, based on the IEEE 802.16-2004 Air Interface Standard is rapidly proving itself as a technology that will play a key role in fixed broadband wireless metropolitan area networks. The first certification lab, established at Cetecom Labs in Malaga, Spain is fully operational and more than 150 WiMAX trials are underway in Europe, Asia, Africa and North and South America. Unquestionably, Fixed WiMAX, based on the IEEE 802.16-2004 [1] Air Interface Standard, has proven to be a cost-effective fixed wireless alternative to cable and DSL services. In December, 2005 the IEEE ratified the 802.16e amendment [2] to the 802.16 standard. This amendment adds the features and attributes to the standard necessary to support mobility. The WiMAX Forum is now defining system performance and certification profiles based on the IEEE802.16e Mobile Amendment and, going beyond the air interface, the WiMAX Forum is defining the network architecture necessary for implementing an end-to-end...

This paper details on the employment of modern, computer-based development tools for the achievement of full real-life experimental frameworks for educational or research purposes. This is achieved through the study, design, implementation and presentation of some initial results, of an OFDM (Orthogonal Frequency Division Multiplexing) transceiver. The design and implementation is done using the TMS320C6713 DSK development kit from "Texas Instruments Inc", in conjunction with Matlab-Simulink from "Mathworks Inc.". This procedure can easily be adopted for the development of several other systems at the domain of communications and signal processing.

The high data transmission rates in the communication channel is a recent growing demand which is achieved by using the multiple input multiple output systems because of their unique properties.. The OFDM systems that adopt the cyclic require only one inverse discrete Fourier transform (IDFT) operation at the low-complexity by means of increasing the transmission diversity in MIMO pilot sequences which minimize the mean square error (MSE) of the channel estimate in traditional MIMO systems are inapplicable to CDD minimum MSE of both the least square (LS) channel estimate and the MMSE channel estimate in CDD systems. The derived criteria are then used to develop a general methodology for determining the sequence. Significantly, the proposed design methodology enables the status of the channel to be estimated using single OFDM symbol. We have compared the performances of channel estimation algorithm by measuring bit error rate vs. SNR with BPSK, QPSK 16

The assignment – selection problem used to find one-to-one match of given " Users " to " Laptops " , the main objective is to minimize the cost as per user requirement. This paper presents satisfactory solution for real assignment – Laptop selection problem using MATLAB coding. KEYWORD Assignment problem, linear integer programming, Revised Ones Assignment Method (ROA), MATLAB programming 2010 Mathematics Subject Classification: 90-02,

This paper presents an efficient architecture for various image filtering algorithms and tumor characterization using Xilinx System Generator (XSG). This architecture offers an alternative through a graphical user interface that combines MATLAB, Simulink and XSG and explores important aspects concerned to hardware implementation. Performance of this architecture implemented in SPARTAN-3E Starter kit (XC3S500E-FG320) exceeds those of similar or greater resources architectures. The proposed architecture reduces the resources available on target device by 50%.

The objective of this paper is to provide safe landing of an UAV on any demanding conditions and can be very useful during the period of floods, rescuing the affected people. It can be also be useful in military operations. This system provides stable method for landing of an aircraft. Image processing technique is used to capture the image and find the angle of inclinations. MATLAB produces four types of image through Image processing technique. They are Gray image, Edge Detection image, Histogram image, object detection image. MATLAB sends the histogram signal to microcontroller using UART. It is used to convert the received parallel data into serial data for transmitting the data to longer distance. Relay drives the DC motor. Angle of inclinations is measured according to the detected image of the surface. MATLAB produces the total inclination value of the surface. DC motor automatically adjusts the landing gear according to the obtained input inclination value of the surface. An UAV is programmed to adjust the landing gear according to angle of inclination. When the landing surface is detected for landing the aircraft, it automatically adjusts the landing gear and lands the aircraft according to the inclined surface of the landing area. I. INTRODUCTION Presently a-days, late progressions in handling capacities have empowered the likelihood of utilizing new computationally immoderate control systems like the Model Predictive Control (MPC) on continuous applications. On this paper, a structure is proposed for the configuration of a managing MPC to be actualized more than an easier, more solid inside circle PID Autopilot without making any changes to its structure. The proposed framework had the capacity add new capacities to the inner circle by making little remedies to its control requests, guaranteeing the agreeability with limitations. UAVs are basically air ship without a human pilot inside. The heaviness of these vehicles can run from a couple of grams to 12 tons having 35 meters of wingspan. We depict the utilization of model predictive control (MPC) utilizing state mapping to the programmed arriving arrangement of a space plane. The controller must be intended to empower the vehicle to take after reference signals as for direction and speed, which are communicated as capacities of the downrange. To track the reference flags, a control data is by and large outlined so one or more perfect transient reactions are figured it out. We additionally have added to a flight control framework in light of this idea. Nonetheless, it was not tasteful for utilization as the controller of a genuine vehicle because of the absence of thought of the data and state requirements. A controller that considers these requirements can be composed by applying MPC. Then again, it is hard to predefine the transient reactions important to track the reference signals, which shift with the current downrange. In this paper, another methodology utilizing state mapping and criticism linearization is proposed to enhance the control execution of following the reference signals. State mapping is inferred to portray a framework in which the reference signs can be taken care of as a steady set point, and the portrayed framework is changed utilizing state input. An unmanned elevated vehicle (UAV) is a flying machine furnished with an on-load up flight controller, information preparing units, sensors, and correspondence framework, which make it fit for performing self-sufficient flight missions in view of a prearranged flight information or driven remotely from a ground control station. This class of vehicles offers more prominent profits over kept an eye on airplane when utilized for high-danger errands or in missions obliging high secrecy. Quick advancement saw in the innovative work of UAVs can be credited to various components, for example, mechanical progressions, political and financial elements among others. UAVs can be characterized into settled-wing and rotorcraft.

Performance of pilot-aided channel estimation
techniques such as the Least Squares (LS) method depends on
not only on the signal-to-noise ratio (SNR), channel conditions
and pilot ratio, but also on the choice of interpolation method
for deriving channel estimates at non-pilot subcarriers. This
paper investigates the bit-error-rate (BER) performance of
linear, spline and Piecewise Cubic Hermite Interpolating
Polynomial (PCHIP) interpolation methods in LS channel
estimation over the three extended ITU channel profiles defined
for Long Term Evolution (LTE) testing. Simulation results
show that applying the linear interpolation method produces
the best BER performance over the fading channel with the
smallest multipath delay spread. It is also shown that the choice
of best interpolation method actually depends on the SNR in
some of the fading channel profiles.

The assignment – selection problem used to find one-to-one match of given " Users " to " Laptops " , the main objective is to minimize the cost as per user requirement. This paper presents satisfactory solution for real assignment – Laptop selection problem using MATLAB coding. KEYWORD Assignment problem, linear integer programming, Revised Ones Assignment Method (ROA), MATLAB programming 2010 Mathematics Subject Classification: 90-02,

The use of aeronautical vehicles and consequently their communication traffic are growing rapidly, and soon there will be demands for channels with larger bandwidths. The L-band digital aeronautical communication system (L-DACS1) was proposed by EUROCONTROL as an OFDM based multicarrier communication system candidate, with channels " inlayed " between distance measuring equipment (DME) channels. We previously proposed a similar communication system based on the Filter Bank Multicarrier (FBMC) technique, which has some significant advantages over L-DACS1. In this paper several diversity and multiple antenna techniques for L-DACS1 and FBMC AG communication systems are investigated. The correlation coefficient between realistic receiver aircraft antenna channels is computed, and using these realistic channels—based upon NASA channel measurements—link performance is simulated to generate BER results. Simulation results show the advantages of using multiple antennas at the receiver, and the antenna separations required (as a function of link distance) to attain nearly uncorrelated channels for two suburban areas. MIMO performance gains are quantified and show significant improvement over single-antenna systems, especially for higher order modulations.

OFDM has come to stay in communication system design due to its ability to mitigate frequency selective fading
in a multipath channel. Intersymbol interference is a major constraint to transmitted bits after conversion of data to be
transmitted from frequency domain to time domain before transmission through the multipath fading channel. To
overcome this, a cyclic prefix is inserted in between the OFDM symbols to prevent (intersymbol interference) ISI, making
the Symbol period longer. In this paper, the effect of cyclic prefix in an OFDM system over idea channel AWGN is
presented.

Growth in technology has led to unprecedented demand for high speed architectures for complex signal processing applications. In 4G wireless communication systems, bandwidth is a precious commodity, and service providers are continuously met with the challenge of accommodating more users with in a limited allocated bandwidth. To increase data rate of wireless medium with higher performance, OFDM (orthogonal frequency division multiplexing) is used. Recently DWT (Discrete wavelet transforms) is adopted in place of FFT (Fast Fourier transform) for frequency translation. Modulation schemes such as 16-QAM, 32-QAM, 64-QAM and 128-QAM (Quadrature amplitude modulation) have been used in the developed OFDM system for both DWT and FFT based model. In this paper we propose a DWT-IDWT based OFDM transmitter and receiver that achieve better performance in terms SNR and BER for AWGN channel. It proves all the wavelet families better over the IFFT-FFT implementation. The OFDM model is developed using Simulink, various test cases have been considered to verify its performance. The DWT-OFDM using Lifting Scheme architecture is implemented on FPGA optimizing hardware, speed & cost. The wavelet filter used for this is Daubechies (9, 7) with N=2. The RTL code is written in Verilog-HDL and simulated in Modelsim. The design is then synthesized in Xilinx and implemented on Virtex5 FPGA board and the results were validated using ChipScope.

This paper presents a model which is Finite Radon Transform based Orthogonal Frequency Division Multiplexing-Interleaver Division Multiple Access (OFDM-IDMA) system for next generation wireless communication system. FRAT is the underlying fundamental concept used for computerized tomography scanning, as well for a wide range of other disciplines, including radar imaging, Geophysical imaging, nondestructive testing and medical imaging. Recently Finite Radon Transform (FRAT) was proposed as a mapping technique in OFDM system Conventional OFDM/QAM systems are robust for multi-path channels due to the cyclically prefixed guard interval which is inserted between consequent symbols to Remove ISI. An interleaver-based multiple access schemes have also been studied in for high spectral efficiency, improved performance and low receiver complexity. This scheme relies on interleaving as the only means to distinguish the signals from different users, and hence it has been called interleave-division multiple-access (IDMA). From the simulation results the FRAT-OFDM-IDMA system performs better as compared to DFT-OFDM-IDMA and DWT-OFDM-IDMA system in term of BER performance for next generation wireless communication system. OFDM is a digital modulation scheme in which a wideband signal is split into a number of narrowband signals. Because the symbol duration of a narrowband signal will be large than that of a wideband signal, the amount of time dispersion caused by multipath delay spread is reduced.

OFDM (Orthogonal Frequency Division Multiplexing) has been raised a new modulation technique. Due to its advantages in multipath fading channel e.g. robust against ISI, ICI and some other advantages like best QoS for multiple users, efficient usage of bandwidth it is suggested to be the modulation technique for next generation 4G networks e.g. LTE. But along with all its advantages there are some disadvantages also e.g. High PAPR (Peak to Average Power Ratio) at the transmitter end and BER (Bit Error Rate) at the receiving end. Since OFDM is only used in the downlink of 4G networks. To reduce the problems of OFDM some techniques e.g. SLM, PTS, Clipping, Coding, & Pre-coding etc are suggested but none of them is reduce the PAPR and BER to an acceptable value. This Paper will discuss some techniques of PAPR & BER reduction, and their advantages and disadvantages in detail.

Chaotic-Binary (CB) sequences have been successfully
employed in selected mapping (SLM) schemes to reduce peak-toaverage
power ratio (PAPR) in Orthogonal Frequency Division Multiplexing
(OFDM) systems. However, construction and implementation
of CB sequences on a Digital Signal Processor (DSP) require a
significant number of complex computations and therefore put additional
constraints on limited DSP resources. This paper presents and
investigates the PAPR reduction capabilities of Binary-Polynomial
(BP) sequences whose coefficients are selected from numbers in a
Fibonacci series. Simulations compare PAPR reduction performance
and the computational complexity of the proposed sequences over
CB sequences. Results show that the proposed BP sequences offer
comparable PAPR reduction performance to CB sequences but have
the advantage of significantly reduced computational complexity.

Several factors drive the use of visible light communication systems as an alternative communication method besides RF communication, one of which is energy saving because the VLC system uses the same device for room lighting, i.e., LED. This study aims to model the VLC systems based on multi-carrier modulation (DCO-OFDM) by using MATLAB software. In this study, VLC the system is modeled on two parts, namely Digital Signal Processing (DSP) and optical channels. The DSP block consists of FFT, convolutional encoder, modulator-demodulator, interleaver-deinterleaver, and synchronizer. For error control coding (ECC), the Viterbi decoder algorithm is used. The results showed that DCO-OFDM frames had been successfully designed. Based on mathematical calculations through the MATLAB approach, the VLC system can work well in 5m x 5m x 3m rooms size: BER equals to zero for the minimum SNR of 10 dB has been obtained while the highest SNR value that can be achieved is ~ 30 dB.

The WiMAX technology, based on the IEEE 802.16-2004 Air Interface Standard is rapidly proving itself as a technology that will play a key role in fixed broadband wireless metropolitan area networks. The first certification lab, established at Cetecom Labs in Malaga, Spain is fully operational and more than 150 WiMAX trials are underway in Europe, Asia, Africa and North and South America. Unquestionably, Fixed WiMAX, based on the IEEE 802.16-2004 [1] Air Interface Standard, has proven to be a cost-effective fixed wireless alternative to cable and DSL services. In December, 2005 the IEEE ratified the 802.16e amendment [2] to the 802.16 standard. This amendment adds the features and attributes to the standard necessary to support mobility. The WiMAX Forum is now defining system performance and certification profiles based on the IEEE802.16e Mobile Amendment and, going beyond the air interface, the WiMAX Forum is defining the network architecture necessary for implementing an end-to-end MobileWiMAX2 network. Release-1 system profiles will be completed in early 2006.This particular paper focuesses on giving an overview of the mobile Wimax technology and LDPC coding typically used to enhance the performance of OFDM systems.

In OFDM systems, the major obstacle is that the
multiplex signal exhibits a very high peak-to-average power
ratio (PAR) In this paper propose a new novel method to
reduce the PAR.A simple and attractive technique is Active
cancellation extension used. However, we observe it cannot
achieve the minimum PAR when the target clipping level is
set below an initially unknown optimum value. A low
clipping ratio is the problem in OFDM system to overcome
this AEC algorithm with adaptive clipping control.
However the simulation results shows our algorithm can
reach the minimum Peak to Average for several clipping
ratios, and also in AWGN channel we calculate the tradeoff
between PAR and the loss in Eb/N0.