scholarly journals BER Analysis of SWT Based OFDM ON LTE

2020 ◽  
Vol 5 (2) ◽  
pp. 82-87
Author(s):  
T. Nagarjuna ◽  
K. Nehru ◽  
G. Nagendra Prasad ◽  
Hema Chowdary
Keyword(s):  
Wavelet Transform ◽  
Bit Error Rate ◽  
Real World ◽  
Channel Model ◽  
Error Rates ◽  
Cyclic Prefix ◽  
Spectrum Efficiency ◽  
Rate Performance ◽  
Awgn Channel ◽  
Modulation Techniques

We proposed to use singular wavelet transform (SWT) in OFDM based LTE because the SWT based system does not require a cyclic prefix, so spectrum efficiency is increased. SWT is used to analyze signals by the coefficients of SWT in both time and frequency domain. In order to investigate the bit error rate performance a practical channel model is required.  Many channel models are proposed to mimic a real world scenario. Out of which Stanford university interim (SUI) channel provides best results so we replaced AWGN channel with SUI channel. We investigated the performance of bit error rates of SWT based OFDM in LTE for different modulation techniques such as QPSK, 64 QAM, 128 QAM under SUI 3 Channel model using SWT based haar and db2 transform. BER is reduced by 2 times when compared to the existing system.

scholarly journals Design and Analysis of MIMO F-OFDM Systems for 5G and Beyond Wireless Communications

2021 ◽  
Vol 10 (2) ◽  
pp. 203-210
Author(s):  
Sohag Sarker ◽  
◽  
Laila Arzuman Ara ◽  
Tahsin Alam ◽  
Tarun Debnath ◽  
...  
Keyword(s):  
Bit Error Rate ◽  
Error Rate ◽  
Channel Coding ◽  
Spectrum Efficiency ◽  
Fir Filters ◽  
Rate Performance ◽  
Ofdm Systems ◽  
Spectrum Utilization ◽  
Modulation Techniques ◽  
Simulation Results

F-OFDM (Filtered-OFDM) is a flexible waveform that has been considered suitable for 5G and beyond systems for its improved spectrum utilization, moderates PAPR, low OOB emission, multiple asynchronous sub-band transmission, and high robustness to frequency selectivity. It can attain a desirable balance between frequency and time localizations for narrow bandwidths. It is also MIMO friendly. In this paper, a comprehensive design and analysis have been made to evaluate the performance of MIMO (4×4) CP-OFDM and F-OFDM systems for message bits transmission using several digital modulation techniques (16-QAM, 16-PSK, 16-DPSK, 64-QAM, 64-PSK, and 64-DPSK), RA channel coding, different windowed (Hanning, Hamming, Blackman, Blackman-Harris, RRC) sinc FIR filters for length N = 513, and MMSE signal detection technique. From MATLAB based simulation results, it is observed that F-OFDM reduces spectrum leakage thus enhances spectrum efficiency than conventional CP-OFDM. F-OFDM based system offers lower BER (Bit Error Rate) performance than CP-OFDM based system.

scholarly journals IMPLEMENTATION AND COMPARISON OF WAVELET TRANSFORM AND FOURIER TRANSFORM IN WI-MAX OFDM SYSTEM

2014 ◽  
pp. 280-283
Author(s):  
P. MAHESH KUMAR ◽  
K. SARADA
Keyword(s):  
Wavelet Transform ◽  
Error Rates ◽  
Cyclic Prefix ◽  
Spectrum Efficiency ◽  
Discrete Wavelet ◽  
Noise Power ◽  
Time Varying ◽  
Ofdm System ◽  
Guard Interval ◽  
International Telecommunications

WIMAX wireless communication is based on ofdm technology which enables going towards 4G Based on IEEE 802.16d-2004. But the reliability of ofdm is limited with the problems of time varying nature of the channel. This can reduced by adding cyclic prefix or guard interval between each block of data symbols. This guard interval minimizes the spectral efficiency in ofdm system. Recently, it was proved that discrete wavelet transform in ofdm system will reduce the isi Inter carrier interference, which is produced by loss of ortho-gonality between carriers and also provides more spectrum efficiency. It is found that proposed wavelet design achieves much lower bit error rates, Increases signal to noise power ratio (SNR), and can be used as an alternative to the Conventional OFDM WIMAX. The proposed OFDM system was modeled tested, and its Performance was found under different International Telecommunications Union (ITU Channel models.

scholarly journals Comparison of Bit Error Rate Performance of Various Digital Modulation Schemes over AWGN and Rayleigh Fading Channels using Simulink

2021 ◽  
Vol 9 (2) ◽  
pp. 7-16
Author(s):  
Md. Firoz Ahmed ◽  
Md. Faysal Ahmed ◽  
Abu Zafor Md. Touhidul Islam
Keyword(s):  
Fading Channels ◽  
Bit Error Rate ◽  
Rayleigh Fading ◽  
Rayleigh Fading Channels ◽  
Rate Performance ◽  
Phase Shift Keying ◽  
Digital Modulation ◽  
Modulation Techniques ◽  
Shift Keying ◽  
Modulation Schemes

Digital modulation increases information capacity, data security, and system availability while maintaining high communication quality. As a result, digital modulation techniques are in higher demand than analog modulation techniques due to their ability to transmit larger amounts of data. Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), Phase Shift Keying (PSK), Differential Phase Shift Keying (DPSK), and Quadrature Amplitude Modulation (QAM) are critical components of current communications systems development, particularly for broadband wireless communications. In this paper, the comparison of bit error rate performance of different modulation schemes (BPSK, QPSK, and16-QAM) and various equalization techniques such as constant modulus algorithm (CMA) and maximum likelihood sequence estimate (MLSE) for the AWGN and Rayleigh fading channels is analyzed using Simulink. BPSK outperforms QPSK and 16-QAM when compared to the other two digital modulation schemes. Among the three digital modulation schemes, BPSK is showing better performance as compared to QPSK and 16-QAM.

scholarly journals Comparison of Bit Error Rate Performance of Different Modulation Techniques over Turbulent FSO Link

2015 ◽  
Vol 109 (12) ◽  
pp. 20-24 ◽  
Author(s):  
Harjeevan Singh ◽  
Mohit Arora
Keyword(s):  
Bit Error Rate ◽  
Error Rate ◽  
Rate Performance ◽  
Modulation Techniques

Bit Error Rate Performance Analysis for Various Modulation Techniques using SUI Channel in Multi-Carrier System

2017 ◽  
Vol 7 (7) ◽  
pp. 419
Author(s):  
Ramakrishna .S ◽  
Priyatam Kumar
Keyword(s):  
Orthogonal Frequency Division Multiplexing ◽  
Channel Model ◽  
Signal To Noise Ratio ◽  
Rate Performance ◽  
Frequency Division ◽  
Carrier System ◽  
Power Requirement ◽  
Channel Condition ◽  
Modulation Techniques ◽  
Selection Of

Orthogonal Frequency Division Multiplexing (OFDM) is of the strong prospects as a future wireless communication system. Improved spectral efficiency has been found in OFDM based on DFT, has a good orthogonality but inter symbol interference (ISI) and inter carrier interference (ICI) degrade the performance. ISI and ICI can be improved by using cyclic prefix (CP). About 20% of bandwidth is consumed by CP. For preferable performance DWT based OFDM gives better outlook than DFT based OFDM.. Three advantages of using DWT are desirable signal to noise ratio, desirable data rate and below per power requirement are given by wavelet based OFDM. Comparison of performances of BER using practical channel model known as Stanford University Interim (SUI) is given in this paper. Consideration to QPSK, 4QAM, 8QAM, 16 -QAM, 32QAM, 64-QAM, 128QAM and 256 QAM has been given in modeling. Channel condition and modulation are the pre - cursors given for the selection of particular performance.

Research on Modulations of Wireless Optical Communication System Based on RS Code under Weak Turbulence Atmosphere Channel

2014 ◽  
Vol 556-562 ◽  
pp. 4945-4949
Author(s):  
Yang Liu ◽  
Guoan Zhang
Keyword(s):  
Bit Error Rate ◽  
Error Rate ◽  
Forward Error Correction ◽  
Error Rates ◽  
Pulse Interval ◽  
Pulse Position Modulation ◽  
Weak Turbulence ◽  
Rate Performance ◽  
Free Space Optical ◽  
Digital Pulse

The free space optical (FSO) system model is analyzed based on on-off keying (OOK), pulse position modulation (PPM), differential pulse position modulation (DPPM) and digital pulse interval modulation (DPIM) under the weak turbulence atmosphere. To improve the system performance, one effective way is to use forward error correction (FEC).The bit error rate (BER) calculating formula of uncoded system is derived under all above the modulations firstly, then as a benchmark, under the case of independent with identical distribution, the average bit error rates of RS coded system are derived, respectively. Simulations of the average bit error rate performance of these systems are done. Simulation results show that, PPM has the best bit error rate performance, RS coded is efficient to get the code gain and to improve jamming-rejection capability of system.

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