Filters








1,598 Hits in 7.7 sec

Bit error rate analysis of different digital modulation schemes in orthogonal frequency division multiplexing systems

S. O. Ajose, A. L. Imoize, O. M. Obiukwu
2018 Nigerian Journal of Technology  
In addition, it was observed that the system performed better over AWGN channel than Rayleigh fading channel for all modulation schemes used.  ...  This study presents the design of an orthogonal frequency division multiplexing (OFDM) system and analyses the performance of the different digital modulation techniques employed in the system.  ...  The BER against Eb/No for OFDM with different sub-carriers scenarios under Rayleigh fading channel are as shown in Figures 7-9.  ... 
doi:10.4314/njt.v37i3.23 fatcat:6y3eu4zz5jfyjgyfz2t765kkou

Analysis of MIMO-OFDM using different Modulation Techniques

Nidhi Kishor, Suresh R.
2016 International Journal of Computer Applications  
In this paper we demonstrated the BER performance of the OFDM system with two different equalizers (ZF and MMSE).  ...  Proposed OFDM system is demonstrated using various modulation techniques that is BPSK, QPSK, 16-QAM and 64-QAM using multipath fading channels that is AWGN (Additive White Gaussian Noise) and Rayleigh  ...  To simulate OFDM system Matrix interleaves are used, the cyclic prefix code of length is said to the channel maximum delay, it will prove channel capacity.  ... 
doi:10.5120/ijca2016912083 fatcat:gzpwrt3gmfcibntiwniigxpjx4

Characterization of Orthogonal Frequency Division Multiplexing (OFDM) Communication Links

Rahmon Kamorudeen Adewale, Ogunti Erastus Olarewaju, Apena Waliu Olalekan
2020 American Journal of Electrical and Electronic Engineering  
(AWGN), Rayleigh and Rician multipath fading channels in OFDM system.  ...  In addition, it was observed that the system performed better in AWGN channel than Rayleigh and Rician fading channels for all the modulation schemes used.  ...  Guard Type Cyclic Prefix Cyclic Prefix Length 25% of NumSC Channel Type AWGN, Rayleigh, Rician Doppler Shift 10hertz  ... 
doi:10.12691/ajeee-8-3-4 fatcat:5fnqbdonozcaloolm6vfxtapoi

Performance analysis of IEEE 802.11n under different STBC rates using 64-QAM

Anastasios Gravalos, Marios Hadjinicolaou, Qiang Ni
2007 2007 2nd International Symposium on Wireless Pervasive Computing  
The design criteria is based on a 4x4 MIMO-OFDM scheme using 64-QAM (Quadrature Amplitude Modulation) technique under Rayleigh frequency-selective fading and flat fading channels.  ...  The main focus of current research and development for the next-generation wireless local area network (WLAN) communication systems is to enhance the link throughput and channel capacity.  ...  Simulation results were carried out using Rayleigh frequency-selective fading and flat fading channel with 64-QAM modulation technique under different STBC code rates.  ... 
doi:10.1109/iswpc.2007.342594 fatcat:vrldwgv65zfrvemi7tgifca3ve

BER Analysis Of BPSK, QPSK, 16-QAM & 64-QAM Based OFDM System Over Rayleigh Fading Channel

Pavan Kumar, Amita Kumari
2016 IOSR Journal of Electronics and Communication Engineering  
In this paper the OFDM system for a number of subcarriers is simulated and sent over Rayleigh fading channel.  ...  The performance of OFDM along with various modulation schemes in the Rayleigh Fading Channel environment is observed and presented in this paper.  ...  This graph shows the bandwidth performance of OFDM under Rayleigh channel for various modulation techniques.  ... 
doi:10.9790/2834-1104036674 fatcat:b6v7zqtnqbh43jgi34c5iyaaba

Performance Analysis of WRAN at Physical Layer of IEEE 802.22 standardization

Emad A., A.I.A. Jabbar, Khalid K.
2016 International Journal of Computer Applications  
In this paper, BER performance of WRAN based on IEEE 802.22 standard is introduced, the performance of physical layer of IEEE 802.22 network is analyzed and simulated over different communication channels  ...  AWGN and multipath fading channels are assumed. BER performance is applied to different types of users and areas.  ...  PHY layer of IEEE 802.22 is modeled and evaluation of BER for different code rates and modulation scheme with noisy channel is presented in [7] . a performance metrics based data channel allocation scheme  ... 
doi:10.5120/ijca2016908086 fatcat:ysekuz7grbbablsat7fslt23hm

Performances Concatenated LDPC based STBC-OFDM System and MRC Receivers

Nejwa El Maammar, Seddik Bri, Jaouad Foshi
2018 International Journal of Electrical and Computer Engineering (IJECE)  
The OFDM wireless communication system incorporates 3/4-rated convolutional encoder under various digital modulations (BPSK, QPSK and QAM) over an additative white gaussian noise (AWGN) and fading (Raleigh  ...  This paper presents the bit error rate performance of the low density parity check (LDPC) with the concatenation of convolutional channel coding based orthogonal frequency-division-multiplexing (OFDM)  ...  LDPC +3/4-rated convolutional encoded OFDM system under different modulation chemes in AWGN and Rayleigh channels 623 applied in conjunction with OFDM systems.  ... 
doi:10.11591/ijece.v8i1.pp622-630 fatcat:ovzkoqpf6bgrrlim6mljlqppb4

Adaptive modulation for OFDM system using fuzzy logic interface

K. Seshadri Sastry, M. S. Prasad Babu
2010 2010 IEEE International Conference on Software Engineering and Service Sciences  
They studied the optimum design of an adaptive modulation scheme based on uncoded M-QAM modulation assisted by channel prediction for the flat Rayleigh fading channel.  ...  The results of computer simulation show the improvement of system capacity in Rayleigh fading channel.  ... 
doi:10.1109/icsess.2010.5552368 fatcat:du6xaubearbdzmh7duu2kusgja

Performance Evaluation of OFDM system with FEC in Rayleigh,Rician and AWGN channel

Smita Jolania, Amol Kumbhare, Sandeep Toshniwal
2014 World Academics Journal of Engineering Sciences  
This paper deals with the analysis of OFDM System with 16-QAM modulation technique over Rayleigh, Rician and Additive White Gaussian Noise (AWGN) fading environ ments with the channel coding and finally  ...  In OFDM the data is modulated using multip le number of sub-carriers that are orthogonal to each other because of which the problems associated with other modulation schemes such as Inter Symbol Interference  ...  OFDM system and cyclic prefix OFDM modulation d ivides the entire frequency selective fading channel into many narrow band flat fading subchannelsl in which high-bit-rate data are transmitted in parallel  ... 
doi:10.15449/wjes.2014.2006 fatcat:c2q6yq7a7zhirguc6xvwtcb5ye

Performance Evaluation of IEEE STD 802.16d Transceiver

Mrunal P. Pathak Mrunal P. Pathak
2013 IOSR Journal of Electronics and Communication Engineering  
System performance evaluated using BER vs SNR for different modulation technique such as 4 QAM, 16 QAM, 64 QAM under different channel condition.  ...  The proposed work is to evaluate performance of IEEE Std 802.16d transceiver in MATLAB R2009b simulink environment.  ...  Shirsat who offered me valuable and constructive tips for my work.  ... 
doi:10.9790/2834-0622126 fatcat:xqcvumkx6fd6nn4j5zjyunjiyy

Frame synchronization, channel estimation scheme and signal compensation using regression method in OFDM systems

Jyh-Horng Wen, Gwo-Ruey Lee, Jia-Wei Liu, Te-Lung Kung
2008 Computer Communications  
The simulation results show the missing probability of frame start with the proposed algorithm performs better than that with the moving average scheme and Beek's scheme under the Rayleigh channel.  ...  Based on an OFDM frame format with adding the pseudo-noise code, the frame timing and the channel impulse response could be obtained by the proposed scheme.  ...  Simulations for the proposed frame synchronization scheme are performed under a two-ray Rayleigh channel.  ... 
doi:10.1016/j.comcom.2008.01.057 fatcat:gqxecpthcrdcrjnvpdme6vjh3i

A Transmit Diversity Technique for OFDM System
IJIREEICE - Electrical, Electronics, Instrumentation and Control

Hema Thota, Ch.Santhi Rani, Kiranmayee Kagitha, Anusha Balagam, Anusha Goriparthi, Naga Lakshmi Devarapalli
2015 IJIREEICE  
This paper presents the performance evaluation of OFDM system, in which fading is reduced by using diversity techniques along with coding methods under various fading channels such as Rician and Rayleigh  ...  Whereas, over Rayleigh channel the BER for OFDM system without including STBC is 1.834x10 -5 and including STBC, it is reduced to 6.345x10 -6 for the same SNR of 14dB.  ...  The number of these cyclic prefix samples, should be bigger than the length of the channel impulse response.  ... 
doi:10.17148/ijireeice.2015.3315 fatcat:gherhlobovdp3h5fxcvvqqehpa

Performance Analysis of a Concatenated LDPC Coded Alamouti-Based STBC-OFDM System on Text Message Transmission

M Mesbahul Alam, A.Z.M Touhidul Islam, S Enayet Ullah
2011 International Journal of Computer Science Engineering and Applications  
modulation schemes and the system is highly effective to combat inherent interferences under AWGN, Rayleigh and Rician fading channels.  ...  The concatenated channel encoded OFDM system deploys various digital modulations (BPSK, QPSK and QAM) over an additative white gaussian noise (AWGN) and other fading (Raleigh and Rician) channels.  ...  Figure 4 . 4 BER of the 1/2-rated convolution and LDPC encoded OFDM system under different modulation schemes and Rayleigh fading channel. 1.0 dB (where the BER values for BPSK and QPSK are 0.002 and  ... 
doi:10.5121/ijcsea.2011.1301 fatcat:rq4lxu6vs5bxrl4yhfvaf5fkeu

Adaptive Modulation for OFDM System Using Fuzzy Logic Interface [chapter]

Seshadri K.
2012 Digital Communication  
This accounts for the clarity of digitally-encoded telephone connections, compact audio disks, and much of the enthusiasm in the engineering community for digital communications technology.  ...  The purpose of this book is to extend and update the knowledge of the reader in the dynamically changing field of digital communication.  ...  They studied the optimum design of an adaptive modulation scheme based on uncoded M-QAM modulation assisted by channel prediction for the flat Rayleigh fading channel.  ... 
doi:10.5772/35901 fatcat:tnk6naaarfgalk2izknn2t66w4

BER Evaluation in LTE SC-FDMA under Multipath Channels

2019 International journal of recent technology and engineering  
Moreover, analysis of BER and SNR for SCFDMA systems are obtained under several channel models and two different sub-mapping.  ...  This evaluation is performed for SCFDMA in uplink by aid of adaptive modulation techniques like QPSK.  ...  Every path has a different power (dB). The cyclic prefix length (CP) is 20 samples.  ... 
doi:10.35940/ijrte.d7767.118419 fatcat:sm7fb6ub2rharapt3x4zb5zjcu
« Previous Showing results 1 — 15 out of 1,598 results