An Optimized Combination of Frequency Domain Adaptive Equalizers

2014 ◽  
Vol 548-549 ◽  
pp. 766-770
Author(s):  
Ke Cheng Leng ◽  
Cheng Bie ◽  
Xi Gong ◽  
Ran Xu ◽  
Ye Cai Guo
Keyword(s):  
Frequency Domain ◽  
Mean Square Error ◽  
Time Domain ◽  
Blind Equalization ◽  
Mean Square ◽  
Constant Modulus ◽  
Equalization Algorithm ◽  
Adaptive Equalizers ◽  
Simulation Results ◽  
The Time Domain

In order to overcome the defects of the high computational loads and selecting the threshold of mean square error (MSE) for time domain decision-directed constant modulus blind equalization algorithm (DD+CMA), a frequency domain parallel decision multi-modulus blind equalization algorithm based on frequency domain MMA(FMMA) and frequency domain LMS (FLMS) algorithm is proposed. The proposed algorithm is composed of the FMMA and FLMS, and the FMMA and FLMS run automatically in soft switching parallel manner. In running process, it is not necessary to selecting the threshold of the MSE. Moreover, the computational loads can be reduced by circular convolution in the frequency domain signals instead of linear one of the time domain signals. Simulation results show that performance of the proposed algorithm outperforms the FLMS and the FMMA algorithm.

New Concurrent Fractionally-Spaced Blind Equalization

2010 ◽  
Vol 108-111 ◽  
pp. 363-368 ◽  
Author(s):  
Wei Rao ◽  
Ye Cai Guo ◽  
Min Chen ◽  
Wen Qun Tan ◽  
Jian Bing Liu ◽  
...  
Keyword(s):  
Steady State ◽  
Convergence Rate ◽  
Mean Square Error ◽  
Blind Equalization ◽  
Mean Square ◽  
Constant Modulus ◽  
Constant Modulus Algorithm ◽  
Underwater Acoustic ◽  
Underwater Acoustic Channels ◽  
Simulation Results

The paper proposes a concurrent constant modulus algorithm (CMA) and decision-directed (DD) scheme for fractionally-spaced blind equalization. The proposed algorithm makes full use of the advantages of CMA and DD algorithm. A novel rule to control the adjustment of DD’s tap weights vector is proposed which avoids the hard switch between CMA and DD in practice. Simulations with underwater acoustic channels are used to compare the proposed algorithm with the famous CMA. And the simulation results show that the proposed algorithm has faster convergence rate and lower steady state mean square error.

Improved Blind Equalization Algorithm and Simulation

2013 ◽  
Vol 325-326 ◽  
pp. 1645-1648
Author(s):  
Wei Ju Cai
Keyword(s):  
Mean Square Error ◽  
Blind Equalization ◽  
Convergence Speed ◽  
Algorithm Analysis ◽  
Mean Square ◽  
Constant Modulus ◽  
Step Size ◽  
Equalization Algorithm ◽  
Convergence Performance ◽  
The Mean

This paper focuses on the constant modulus Busgang blind equalization algorithm (CMA blind equalization algorithm in Constant, The Modulus Algorithm). Analysis of the convergence performance of the traditional CMA blind equalization algorithm, the fixed step size, convergence speed and convergence of mutual constraint between the precision of its application under great restrictions is demonstrated in the paper. In order to solve this contradiction, this paper presents a CMA blind equalization algorithm based on the mean square error (MSE Mean Square Error).

scholarly journals Adaptive modulation based on steady-state mean square error for underwater acoustic communication

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Zhiyong Liu ◽  
Zhoumei Tan ◽  
Fan Bai
Keyword(s):  
Steady State ◽  
Mean Square Error ◽  
Adaptive Modulation ◽  
Blind Equalization ◽  
Training Sequence ◽  
Transmission Efficiency ◽  
Underwater Acoustic Communication ◽  
Mean Square ◽  
Modulation Mode ◽  
Simulation Results

AbstractTo improve the transmission efficiency and facilitate the realization of the scheme, an adaptive modulation (AM) scheme based on the steady-state mean square error (SMSE) of blind equalization is proposed. In this scheme, the blind equalization is adopted and no training sequence is required. The adaptive modulation is implemented based on the SMSE of blind equalization. The channel state information doesn’t need to be assumed to know. To better realize the adjustment of modulation mode, the polynomial fitting is used to revise the estimated SNR based on the SMSE. In addition, we also adopted the adjustable tap-length blind equalization detector to obtain the SMSE, which can adaptively adjust the tap-length according to the specific underwater channel profile, and thus achieve better SMSE performance. Simulation results validate the feasibility of the proposed approaches. Simulation results also show the advantages of the proposed scheme against existing counterparts.

scholarly journals Enhanced CORDIC Based Rotator Design for Sinusoidal Transforms

2020 ◽  
Vol 9 (3) ◽  
pp. 1001-1004
Keyword(s):  
Fourier Transform ◽  
Frequency Domain ◽  
Discrete Fourier Transform ◽  
Mean Square Error ◽  
Time Domain ◽  
Basis Function ◽  
The Other ◽  
Mean Square ◽  
Circular Rotation ◽  
The Mean

Transforms play an important role in conversion of information from one domain to the other. To be more specific transforms like Discrete Fourier transform (DFT) and Discrete Cosine transform (DCT) helps us to migrate from one time domain to frequency domain based on the basis function selected. The basis function of the every sinusoidal transform carries out a circular rotation to convert information from one domain to the other. There are applications related to communication which requires this rotation into the hyperbolic trajectory as well. Multiplierless algorithm like CORDIC improves the latency of the transforms by eliminating the number of multipliers in the basis function. In this paper we have designed and implemented enhanced version of CORDIC based Rotator design. The Enhanced version is simulated for order 1 to order 36 to emphasize on the results of the proposed algorithm. Results shows that the enhanced CORDIC rotator design surpasses the Mean square error after the order 18 compared to standard CORDIC. Unified CORDIC also can be implemented using the said algorithm to implement different three trajectories.

Induction Motor Fault Diagnosis Using Voltage Spectrum of Auxiliary Winding and Lissajous Curve of its Park Components

2013 ◽  
Vol 805-806 ◽  
pp. 963-979 ◽  
Author(s):  
Lamiaâ El Menzhi ◽  
Abdallah Saad
Keyword(s):  
Fourier Transform ◽  
Fault Diagnosis ◽  
Frequency Domain ◽  
Induction Motor ◽  
Discrete Fourier Transform ◽  
Time Domain ◽  
New Method ◽  
Spectrum Simulation ◽  
Simulation Results ◽  
The Time Domain

In this paper, a new method for induction motor fault diagnosis is presented. It is based on the so-called an auxiliary winding voltage and its Park components. The auxiliary winding is a small coil inserted between two of the stator phases. Expressions of the inserted winding voltage and its Park components are presented. After that, discrete Fourier transform analyzer is required for converting the signals from the time domain to the frequency domain. A Lissajous curve formed of the two Park components is associated to the spectrum. Simulation results curried out for non defected and defected motor show the effectiveness of the proposed method.

Circuit Models of Lossy Multic onductor Transmission Lines: Incident Plane Wave Effect

2016 ◽  
Vol 6 (5) ◽  
pp. 2369
Author(s):  
Saih Mohamed ◽  
Rouijaa Hicham ◽  
Ghammaz Abdelilah
Keyword(s):  
Plane Wave ◽  
Frequency Domain ◽  
Transmission Lines ◽  
Time Domain ◽  
Method Of Characteristics ◽  
Incident Plane Wave ◽  
Wave Effect ◽  
Incident Plane ◽  
Simulation Results ◽  
The Time Domain

<p>In this paper, we concentrate on the variety impacts of incident plane wave on multiconductor transmission lines, utilizing Branin’s method, which is alluded to as the method of characteristics. The model can be directly used for the time-domain and frequency-domain analyses, Moreover,  it had the advantage of being used without the need of setting the  preconditions of  the  charges  applied  to  its  ends; this permits it to be effortlessly embedded in circuit simulators, for example Spice, Saber, and Esacap. This model validity is affirmed by contrasting our simulation results under ESACAP and different results, and we will talk about variety impacts of incident plane wave.</p>

Wavelet Frequency Domain Constant Modulus Blind Equalization Algorithm Based on Fractional Lower Order Statistics

2012 ◽  
Vol 198-199 ◽  
pp. 1497-1500
Author(s):  
Jun Guo ◽  
Ye Cai Guo ◽  
Qu Chen ◽  
Yi Bo Zhao
Keyword(s):  
Frequency Domain ◽  
Order Statistics ◽  
Lower Order ◽  
Blind Equalization ◽  
Constant Modulus ◽  
Constant Modulus Algorithm ◽  
Equalization Algorithm ◽  
Domain Constant ◽  
Fractional Lower Order Statistics ◽  
Orthogonal Wavelet Transform

In order to improve the performance of constant modulus algorithm(CMA) in the noise which obeys α-stable distribution, wavelet frequency domain constant modulus blind equalization algorithm based on fractional lower order statistics(WT-FLOSFCMA) is proposed. This proposed algorithm uses fractional lower order statistics to restrain α-stable noise, and its computational loads can be greatly reduced by using FFT technique and the overlapping retention law. In the proposed algorithm, according to the minimum dispersion coefficient criterion, the CMA is optimized, orthogonal wavelet transform is used to improve the convergence rate. The computer simulations in underwater acoustic channels show that the proposed algorithm outperforms than CMA, orthogonal wavelet transform constant modulus algorithm(WT-CMA),and frequency domain blind equalization algorithm based on fractional lower order statistics(FLOSFCMA) in suppressing with inter-symbol interfere, improving convergence rate, and reducing mean square error.

scholarly journals Circuit Models of Lossy Multic onductor Transmission Lines: Incident Plane Wave Effect

2016 ◽  
Vol 6 (5) ◽  
pp. 2369
Author(s):  
Saih Mohamed ◽  
Rouijaa Hicham ◽  
Ghammaz Abdelilah
Keyword(s):  
Plane Wave ◽  
Frequency Domain ◽  
Transmission Lines ◽  
Time Domain ◽  
Method Of Characteristics ◽  
Incident Plane Wave ◽  
Wave Effect ◽  
Incident Plane ◽  
Simulation Results ◽  
The Time Domain

<p>In this paper, we concentrate on the variety impacts of incident plane wave on multiconductor transmission lines, utilizing Branin’s method, which is alluded to as the method of characteristics. The model can be directly used for the time-domain and frequency-domain analyses, Moreover,  it had the advantage of being used without the need of setting the  preconditions of  the  charges  applied  to  its  ends; this permits it to be effortlessly embedded in circuit simulators, for example Spice, Saber, and Esacap. This model validity is affirmed by contrasting our simulation results under ESACAP and different results, and we will talk about variety impacts of incident plane wave.</p>

A New Blind Equalization Algorithm Suitable for Sparse Underwater Acoustic Channel

2012 ◽  
Vol 195-196 ◽  
pp. 149-153
Author(s):  
Ting Ting Zhu ◽  
Xiao Tao Jiao
Keyword(s):  
Blind Equalization ◽  
Constant Modulus ◽  
Shallow Sea ◽  
Underwater Acoustic Channel ◽  
Underwater Acoustic ◽  
Acoustic Channel ◽  
Equalization Algorithm ◽  
Long Time ◽  
Simulation Results ◽  
Sparse Underwater Acoustic Channel

The Constant Modulus Algorithms is a mature algorithm for a long time. The researchers are fond of its solidity. But in the area of shallow sea or blue sea, the CMA has poor constringency. In this passage, based on a improved blind equalization algorithm, we proposed a new algorithm which suitable for sparse underwater acoustic channel. The computer simulation results demonstrate fast convergence and fewer accounts.

LMMSE Equalization Algorithm Research Based on 0.5chip Level

2014 ◽  
Vol 701-702 ◽  
pp. 974-978
Author(s):  
Shan Ling Liu
Keyword(s):  
Mean Square Error ◽  
Minimum Mean Square Error ◽  
Mean Square ◽  
Spreading Codes ◽  
Equalization Algorithm ◽  
Simulation Results ◽  
Performance Of Algorithm ◽  
Better Than ◽  
Inter Symbol Interference

The LMMSE equalization filter based on minimum mean square error (MMSE) criterion can effectively suppress the inter-symbol interference caused by multi-path and recover the orthogonality among the spreading codes. In this paper, LMMSE equalizer with 0.5chip level algorithm is studied in the downlink of the UTRA HSPA+ system and the simulation results show that the performance of algorithm with 0.5chip level is better than the algorithm with one chip level.

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