scholarly journals PERBANDINGAN POWER SPECTRAL DENSITY SISTEM OWDM DAN OFDM PADA KANAL RAYLEIGH

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Yuyun Siti Rohmah ◽  
Ali Muayyadi ◽  
Rina Pudji Astuti
Keyword(s):  
Wavelet Transform ◽  
Spectral Density ◽  
Discrete Wavelet Transform ◽  
Power Spectral Density ◽  
Orthogonal Frequency Division Multiplexing ◽  
Discrete Wavelet ◽  
Frequency Division Multiplexing ◽  
Frequency Division ◽  
Orthogonal Wavelet ◽  
Power Spectral

OFDM (Orthogonal Frequency Division Multiplexing) merupakan teknik modulasi multicarrier untuk mengatasi permasalahan kanal multipath seperti frekuensi selektif fading. Orthogonalitas pada sistem OFDM menghasilkan banyak sub-carrier yang dapat ditransmisikan secara bersamaan pada spektrum frekuensi yang terbatas tanpa saling berinterferensi. Efesiensi bandwidth didapat karena masing-masing sub-carrier saling orthogonal sehingga antara sub-carrier yang berdekatan dapat dibuat overlapping. OWDM (Orthogonal wavelet division multiplex) merupakan suatu sistem multicarrier alternatif dariOFDM dan telah diteliti sebagai kandidat yang dapat diaplikasikan pada wirelesscommunication. Sistem OWDM menggunakan Inverse Discrete wavelet transform (IDWT) sebagai pembangkit subcarrier-subcarrier yang saling orthogonal dan berfungsi sebagai modulator. Sedangkan DWT (Discrete Wavelet Transform) digunakan sebagai demodulator. Penelitian ini membandingkan power spectral density dari sistem OWDM dan OFDM. Dari hasil simulasi perbandingan power spectral density (PSD) didapatkan bahwa PSD darimasing-masing sistem sama. Pada OWDM, pembagian band frekuensi untuk setiap sub-band berbeda kecuali sub-band pada level yang sama. Semakin tinggi level sub-band maka semakin lebar band frekuensinya.

scholarly journals Study of the Discrete Wavelet Transform Based Designed System Under Different Simulation Conditions

2020 ◽  
Vol 14 ◽  
Keyword(s):  
Signal Processing ◽  
Wavelet Transform ◽  
Discrete Wavelet Transform ◽  
Amplitude Modulation ◽  
Orthogonal Frequency Division Multiplexing ◽  
Pulse Amplitude ◽  
Discrete Wavelet ◽  
Pulse Amplitude Modulation ◽  
Frequency Division Multiplexing ◽  
Frequency Division

Wavelet Transforms is an Important Part of, Systems Theory and Signal Processing and finds numerous important applications in Science and Engineering. In this paper, we investigated the performance of proposed scheme coded Discrete wavelet transform based Orthogonal frequency division multiplexing scheme over Additive white Gaussian noise channel using Pulse Amplitude Modulation in terms of Energy bits per noise ratio values. The simulation has been done using MATLAB software and results are compared with ½ rate convolution coded Discrete wavelet transform based Orthogonal frequency division multiplexing system. It is found by MATLAB simulations that the performance of proposed scheme coded Discrete wavelet transform based Orthogonal frequency division multiplexing outperforms than that of ½ rate convolution encoded Discrete wavelet transform based Orthogonal frequency division multiplexing with 16-Pulse Amplitude Modulation. Along with this, different orders of reverse biorthogonal and biorthogonal wavelets are implemented to simulate the proposed system with 16-Pulse Amplitude Modulation scheme. The performance of proposed system is compared and it is found that proposed system performs better than conventional system under all different simulation conditions. This study finds important applications in Signal Processing.

scholarly journals Performance investigation of WOFDM for 5G wireless networks

2019 ◽  
Vol 9 (4) ◽  
pp. 3153
Author(s):  
M. F. Ghanim
Keyword(s):  
Wireless Networks ◽  
Wavelet Transform ◽  
Discrete Wavelet Transform ◽  
Orthogonal Frequency Division Multiplexing ◽  
Original System ◽  
Discrete Wavelet ◽  
Frequency Division Multiplexing ◽  
Frequency Division ◽  
Ofdm System

<p>Nowadays, emerging wireless networks scenarios such as the proposed systems for 5G is discussed widely with diverse requirements. Orthogonal Frequency Division Multiplexing (OFDM) is a conservative proposal which is used to build 5G WOFDM system (Wavelet OFDM system). The simulation of the system is initialized with BPSK then with QAM and 64-QAM the system is improved by increasing the number of levels of Discrete Wavelet Transform to five levels and finally compared with original system to prove that the it is convenient for 5G Wireless networks.</p>

scholarly journals 5G Multi-Carrier Modulation Techniques: Prototype Filters, Power Spectral Density, and Bit Error Rate Performance

2021 ◽  
Author(s):  
Shaik Nilofer ◽  
Praveen Kumar Malik
Keyword(s):  
Wireless Communication ◽  
Spectral Density ◽  
Power Spectral Density ◽  
Bit Error Rate ◽  
Error Rate ◽  
Orthogonal Frequency Division Multiplexing ◽  
Frequency Division Multiplexing ◽  
Frequency Division ◽  
Fifth Generation ◽  
Power Spectral

Abstract In recent years for fourth-generation wireless communication systems Orthogonal Frequency Division Multiplexing (OFDM) multi-carrier modulation (MCM) has been an excellent choice. But for the fifth-generation air interface, the choice of multi-carrier modulation remains the biggest challenge. A potential multi-carrier modulation or candidate waveforms are required for the design of the physical layer. This paper highlights the merits and limitations of new candidate waveforms for fifth-generation wireless communication system. This paper mainly reviews Orthogonal frequency division multiplexing, Filtered-OFDM (F-OFDM), Universal Frequency Division Multiplexing (UFMC), Filtered Bank Multi-Carrier Modulation (FBMC), and Generalized Frequency Division Multiplexing (GFDM). This paper mainly reviews some of the comparisons of the parameters as power spectral density and bit error rate.

scholarly journals Lucas Algorithm for Medical Images Encryption and Transmission using Orthogonal Frequency Division Multiplexing for Medical Health Information Systems and its VLSI Realization

2021 ◽  
Vol 17 (06) ◽  
pp. 128
Author(s):  
Gangadhar Ch ◽  
Md Habibulla
Keyword(s):  
Wavelet Transform ◽  
Information Systems ◽  
Health Information ◽  
Image Encryption ◽  
Orthogonal Frequency Division Multiplexing ◽  
Medical Images ◽  
Health Information Systems ◽  
Discrete Wavelet ◽  
Frequency Division Multiplexing ◽  
Frequency Division

<p>Security of medical images is critical for transmission of medical images and relevant patient information through public health information systems networks. Image encryption is an important tool for protecting Medical images by converting them into unrecognisable formats for the transmission and receiption of medical images.  This paper proposes an algorithm for medical image encryption using Lucas Algorithm, and a discrete wavelet transform based transmission and reception technique, which is known as orthogonal frequency division multiplexing(OFDM). This paper presents an implementation of Lucas Algorithm for image encryption and combines it with Discrete wavelet transform orthogonal frequency division multiplexing using Field Programmable Gate Array.</p>

Extraction Feature of Spindle Unbalance of Machine Tool Based on the Wavelet Transform

2011 ◽  
Vol 279 ◽  
pp. 313-317
Author(s):  
Dong Ju Chen ◽  
Jin Wei Fan ◽  
Fei Hu Zhang
Keyword(s):  
Wavelet Transform ◽  
Spectral Density ◽  
Machine Tool ◽  
Power Spectral Density ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Power Spectral ◽  
Density Analysis ◽  
Power Spectral Density Analysis ◽  
Flatness Error

A new method for extracting spectrum feature of spindle unbalance of machine tool is proposed. The flatness error of workpiece surface includes much errors information, and the information contains high frequency signal and low frequency signal. For these errors information, a new identification method of turning errors of workpiece based on the wavelet transform and power spectral density analysis is proposed. According to the focal variation character of wavelet and the energy value of power spectral density analysis, the feature of spindle unbalance from the measured flatness error of workpiece is extracted and identified.

A New Method for MIMO-OFDM Channel Estimation Based on Discrete Wavelet Transform

2012 ◽  
Vol 182-183 ◽  
pp. 2066-2070
Author(s):  
Hui Shi ◽  
Ren Wang Song ◽  
Gang Fei Wang
Keyword(s):  
Wavelet Transform ◽  
Channel Estimation ◽  
Discrete Wavelet Transform ◽  
Orthogonal Frequency Division Multiplexing ◽  
Multiple Input Multiple Output ◽  
Mimo Channel ◽  
Discrete Wavelet ◽  
Input Multiple Output ◽  
Estimation Scheme ◽  
Mimo Ofdm

This paper puts forward a suitable channel estimation scheme for multiple input multiple output and orthogonal frequency division multiplexing system (MIMO-OFDM) based on discrete wavelet transform. According to the least-squares standard (LS), this plan uses pilot to estimate the unit impulse response of MIMO channel firstly, then does wavelet denoising in changing domain, in order to reduce the frequency spectrum leakage and improve the estimation precision. At the same time, this method does not need to know channel information in advance, and can follow up the changes of channel on time with good error rate performance.

Sign in / Sign up

Export Citation Format

Share Document