A new approach, based on the waveform relaxation technique and fast Walsh trans-form, is presented to analyze the coupled loosy transmission lines (CLTL) with arbitrary terminalnetworks. The simulation accuracy of the...A new approach, based on the waveform relaxation technique and fast Walsh trans-form, is presented to analyze the coupled loosy transmission lines (CLTL) with arbitrary terminalnetworks. The simulation accuracy of the new method can be greatly improved, the disadvantagewhich always exists in previous methods can be avoided and a considerable saving in time andmemory of CPU is obtained.展开更多
Spectrum sensing is a key technology to improve spectrum efficiency. In this paper, we propose a novel signal detection method based on Walsh transform for spectrum sensing. The main idea behind is that the received s...Spectrum sensing is a key technology to improve spectrum efficiency. In this paper, we propose a novel signal detection method based on Walsh transform for spectrum sensing. The main idea behind is that the received signal is transformed into another domain by Walsh transform and the test statistic is obtained by exploiting the feature of the useful signal in the new domain. The new method can perform well at low signal-to-noise rate (SNR). Simulation results show that the proposed method has better performance than the spectral feature detection based on power spectrum.展开更多
The Walsh transform is an important tool to investigate cryptographic properties of Boolean functions.This paper is devoted to study the Walsh transform of a class of Boolean functions defined as g(x)=f(x)Tr^(n)_(1)(x...The Walsh transform is an important tool to investigate cryptographic properties of Boolean functions.This paper is devoted to study the Walsh transform of a class of Boolean functions defined as g(x)=f(x)Tr^(n)_(1)(x)+h(x)Tr^(n)_(1)(δx),by making use of the known conclusions of Walsh transform and the properties of trace function,and the conclusion is obtained by generalizing an existing result.展开更多
Walsh-Hadamard transform （WriT） can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enorm...Walsh-Hadamard transform （WriT） can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enormous computer memory which limits the application of WriT. In order to solve this problem, a method based on segmented WriT is proposed in this paper. The coefficient vector of high dimension is reshaped and two vectors of lower dimension are obtained. Then the WriT is operated and the requirement for computer memory is much reduced. The code rate and the constraint length of convolutional code are detected from the Walsh spectrum. And the check vector is recovered from the peak position. The validity of the method is verified by the simulation result, and the performance is proved to be optimal.展开更多
This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency ...This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency division multiple access(OFDMA)with extra advantage of low Peak to Average Power Ratio(PAPR). Moreover,this article also suggests the application of Walsh Hadamard transform(WHT)for linear precoding(LP)to improve the PAPR performance of the system. Supremacy of the proposed transceiver over conventional Fast Fourier transform(FFT)based SCFDMA is shown through simulated results in terms of PAPR,spectral efficiency(SE)and bit error rate(BER).展开更多
文摘A new approach, based on the waveform relaxation technique and fast Walsh trans-form, is presented to analyze the coupled loosy transmission lines (CLTL) with arbitrary terminalnetworks. The simulation accuracy of the new method can be greatly improved, the disadvantagewhich always exists in previous methods can be avoided and a considerable saving in time andmemory of CPU is obtained.
文摘Spectrum sensing is a key technology to improve spectrum efficiency. In this paper, we propose a novel signal detection method based on Walsh transform for spectrum sensing. The main idea behind is that the received signal is transformed into another domain by Walsh transform and the test statistic is obtained by exploiting the feature of the useful signal in the new domain. The new method can perform well at low signal-to-noise rate (SNR). Simulation results show that the proposed method has better performance than the spectral feature detection based on power spectrum.
基金Supported by the Natural Science Foundation of Anhui Higher Education Institutions of China(KJ2020ZD008)Key Research and Development Projects in Anhui Province(202004a05020043)the Graduate Innovation Fund of Huaibei Normal University(yx2021022)。
文摘The Walsh transform is an important tool to investigate cryptographic properties of Boolean functions.This paper is devoted to study the Walsh transform of a class of Boolean functions defined as g(x)=f(x)Tr^(n)_(1)(x)+h(x)Tr^(n)_(1)(δx),by making use of the known conclusions of Walsh transform and the properties of trace function,and the conclusion is obtained by generalizing an existing result.
基金supported by the National Natural Science Foundation of China(61072120)
文摘Walsh-Hadamard transform （WriT） can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enormous computer memory which limits the application of WriT. In order to solve this problem, a method based on segmented WriT is proposed in this paper. The coefficient vector of high dimension is reshaped and two vectors of lower dimension are obtained. Then the WriT is operated and the requirement for computer memory is much reduced. The code rate and the constraint length of convolutional code are detected from the Walsh spectrum. And the check vector is recovered from the peak position. The validity of the method is verified by the simulation result, and the performance is proved to be optimal.
文摘This article proposes a new transceiver design for Single carrier frequency division multiple access(SCFDMA)system based on discrete wavelet transform(DWT). SCFDMA offers almost same structure as Orthogonal frequency division multiple access(OFDMA)with extra advantage of low Peak to Average Power Ratio(PAPR). Moreover,this article also suggests the application of Walsh Hadamard transform(WHT)for linear precoding(LP)to improve the PAPR performance of the system. Supremacy of the proposed transceiver over conventional Fast Fourier transform(FFT)based SCFDMA is shown through simulated results in terms of PAPR,spectral efficiency(SE)and bit error rate(BER).
