In this paper, an adaptive circular array antenna is applied to DS/SS (Direct Sequence / Spread Spectrum) IVC (Inter-Vehicle Communication) under shadowing environment. The DS/SS scheme is an attractive technique for ...
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ISBN:
(纸本)9781457721977
In this paper, an adaptive circular array antenna is applied to DS/SS (Direct Sequence / Spread Spectrum) IVC (Inter-Vehicle Communication) under shadowing environment. The DS/SS scheme is an attractive technique for the IVC system because it has advantages for CDMA (Code Division Multiple Access) capability and so on. However, the near-far problem is occurred in the DS/SS scheme. Shadowing the radio paths by large vehicles is also significant problem for the IVC system. To solve those problems, a lms (Least Mean Square) adaptive circular array antenna is proposed. The array antenna can be controlled its directivity when the receiving vehicle knows the information of the target vehicle. The PER (Packet Error Rate) and the throughput performances are evaluated. And the performances are compared with the ordinary system by using omini-directional antenna. From the simulation results, the adaptive circular array antenna is effective for the near-far problem and influence of shadowing in the DS/SS IVC system.
This study presents a technique for separation of Heart Sound Signal (HSS) from Lung Sound Signal (LSS) using Adaptive Line Enhancer (ALE) with Least Mean Square (lms) algorithm with real time recorded sound signal. W...
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Recently, many adaptive filtering proposals that discuss the sparsity of the system have been appeared These proposals are, mainly, based on the least-mean-square (lms) algorithm. In this paper we propose two algorith...
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ISBN:
(纸本)9781479948741
Recently, many adaptive filtering proposals that discuss the sparsity of the system have been appeared These proposals are, mainly, based on the least-mean-square (lms) algorithm. In this paper we propose two algorithms that exploit the sparsity of the system and based on the mixed norm lms (MN-lms) algorithm. The first algorithm is proposed by adding I-1-norm penalty to the cost function of the MN-lms algorithms. This term enables us to attract the near-to-zero filter coefficients into zero very fast However, when the system is highly non sparse, the algorithm almost fails. Because of that, we propose another algorithm that uses an approximation of thel(0)-norm penalty term in the cost function of the MN-lms algorithm. This provides high performance even if the system is highly non sparse system. The performances of the proposed algorithms are compared to those of the lms and MN-lms algorithms in an acoustic sparse system identification setting. The proposed algorithms provide significant performances compared to the others.
A novel nonlinear foreground calibration of pipeline AID converters based on lms algorithm has been proposed and verified by macro-based simulation as well as measurement of test chip. The prototype 23-mW 50-MS/s 10-b...
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ISBN:
(纸本)9781424438273
A novel nonlinear foreground calibration of pipeline AID converters based on lms algorithm has been proposed and verified by macro-based simulation as well as measurement of test chip. The prototype 23-mW 50-MS/s 10-bit pipeline ADC in 0.13-mu m CMOS has confirmed that the proposed calibration can accurately and rapidly correct the inaccuracy caused both by heavy nonlinearity of low-gain op-amps and by their incomplete settling without requiring any dedicated voltage references, complicated structures or timing sequence and hence can be used for various applications.
In this paper, lms (Least Mean Square) adaptive array antenna is applied to IVC(Inter-Vehicle Communication) in order to reduce interference which is caused by surrounding vehicles. The lms adaptive array antenna has ...
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ISBN:
(纸本)9781424478668
In this paper, lms (Least Mean Square) adaptive array antenna is applied to IVC(Inter-Vehicle Communication) in order to reduce interference which is caused by surrounding vehicles. The lms adaptive array antenna has a characteristic that the control of directivity is possible according to surrounding radio wave condition, if the receiving vehicle knows the information of the target vehicle. Under the case where the adaptive array antenna is used in IVC systems, packet error rate characteristic, throughput performance and improvement in near-far problem are evaluated by comparing with the performance of the IVC system using omni-directional antenna.
This paper studies the statistical behavior of an affine combination of the outputs of two lms adaptive filters that simultaneously adapt using the same white Gaussian input. The purpose of the combination is to obtai...
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ISBN:
(纸本)9781424414833
This paper studies the statistical behavior of an affine combination of the outputs of two lms adaptive filters that simultaneously adapt using the same white Gaussian input. The purpose of the combination is to obtain an lms adaptive filter with fast convergence and small steady-state mean-square error (MSE). The linear combination studied is a generalization of the convex combination, in which the combination factor is restricted to the interval (0, 1). The viewpoint is taken that each of the two filters produces dependent estimates of the unknown channel. Thus, there exists a sequence of optimal affine combining coefficients which minimizes the MSE. The optimal unrealizable affine combiner is studied and provides the best possible performance for this class. Then, a new scheme is proposed for practical applications. It is shown that the practical scheme yields close-to-optimal performance when properly designed (as suggested by the theoretical optimal).
Software radio technology makes possible the implementation Of highly flexible receivers architectures that employ sophisticated signal processing algorithms such as those required for equalization. The implementation...
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ISBN:
(纸本)0780386566
Software radio technology makes possible the implementation Of highly flexible receivers architectures that employ sophisticated signal processing algorithms such as those required for equalization. The implementation of advanced DS-CDMA receivers based on adaptive filter principles is becoming an area of considerable interest. The focus of the paper is the introduction of a dynamically reconfigurable architecture and an adaptive linear receiver for CDMA systems in mobile communication. This paper, presents a flexible single-user receiver that can support a variety of applications and analyses the convergence behaviour of the least mean square (lms) filter when used in an adaptive code division multiple access (CDMA) detector consisting of a tapped delay line with adjustable tap weights.
The tracking performances of the lms and Nlms algorithms are compared when the input of the adaptive filter is nonstationary. The analysis is done in the context of tracking a Markov plant. A periodic scenario of the ...
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ISBN:
(纸本)9781424497218
The tracking performances of the lms and Nlms algorithms are compared when the input of the adaptive filter is nonstationary. The analysis is done in the context of tracking a Markov plant. A periodic scenario of the variation of the input power is considered. The steady-state peak mean square deviation is used as the tracking performance measure. It is found that one algorithm outperforms the other depending on the values of the rate of variation of the input power, the minimum input power, the noise variance, and the mean square plant parameter increments.
Least Mean Square (lms) filters are the most used adaptive filters with applications ranging from channel equalization to system identification and noise cancellation. An lms adaptive filter includes two main parts: a...
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ISBN:
(纸本)9781728160443
Least Mean Square (lms) filters are the most used adaptive filters with applications ranging from channel equalization to system identification and noise cancellation. An lms adaptive filter includes two main parts: a FIR filter and a block for coefficients updating that exploits the lms algorithm. The hardware implementation of lms filter requires a significant number of multipliers, adders and registers, resulting in power consumption issues. In this paper we propose a novel approximate, low-power implementation of the coefficients update block. In the proposed approach, the signal precision is dynamically scaled by using a time-variable rounding. The circuit can select between three levels of precision: no rounding, light rounding and strong rounding. An observation block decides at runtime the rounding level, based on the magnitude of the lms error signal. In this way, it is possible to minimize the convergence error while significantly reducing the switching activity when the algorithm is close to the convergence. VLSI implementation in TSMC 28nm CMOS technology shows that proposed approach results in a maximum power saving of 27% with respect to a standard lms, with negligible degradation of error performances and limited area overhead.
Musical transcription requires much burden even for specialists in the musical field therefore, many trials of automatie transcription have been being done actively. As musical signals are substantially time varying, ...
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ISBN:
(纸本)9781509025978
Musical transcription requires much burden even for specialists in the musical field therefore, many trials of automatie transcription have been being done actively. As musical signals are substantially time varying, we have investigated an lms-based Fourier analyzer to accommodate time varying characteristics. In this article, frequency response of the above adaptive algorithm is briefl reviewed in order to provide insight of the adaptive algorithm. And then, the analyzing system of Kagura Japanese folk music musical signals, which converts analyzed results to the MIDI format, is described. Finally, results in MIDI format are converted to musical scores by using commercially available software in order to verify the validity of the system.
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