Based on the iterative bit-filling procedure, a computationally efficient bit and power allocation algorithm is presented. The algorithm improves the conventional bit-filling algorithms by maintaining only a subset of...Based on the iterative bit-filling procedure, a computationally efficient bit and power allocation algorithm is presented. The algorithm improves the conventional bit-filling algorithms by maintaining only a subset of subcarriers for computation in each iteration, which reduces the complexity without any performance degradation. Moreover, a modified algorithm with even lower complexity is developed, and equal power allocation is introduced as an initial allocation to accelerate its convergence. Simulation results show that the modified algorithm achieves a considerable complexity reduction while causing only a minor drop in performance.展开更多
A computationally efficient soft-output detector with lattice-reduction （LR） for the multiple-input multiple-output （MIMO） systems is proposed. In the proposed scheme, the sorted QR de- composition is applied on t...A computationally efficient soft-output detector with lattice-reduction （LR） for the multiple-input multiple-output （MIMO） systems is proposed. In the proposed scheme, the sorted QR de- composition is applied on the lattice-reduced equivalent channel to obtain the tree structure. With the aid of the boundary control, the stack algorithm searches a small part of the whole search tree to generate a handful of candidate lists in the reduced lattice. The proposed soft-output algorithm achieves near-optimal perfor- mance in a coded MIMO system and the associated computational complexity is substantially lower than that of previously proposed methods.展开更多
This paper proposes an electronic image stabilization algorithm based on efficient block matching on the plane. This algorithm uses a hexagonal search algorithm, and uses the bit-planes to estimate and compensate for ...This paper proposes an electronic image stabilization algorithm based on efficient block matching on the plane. This algorithm uses a hexagonal search algorithm, and uses the bit-planes to estimate and compensate for the translational motion between video sequences at the same time;As for the rotary motion vector generated in the video sequences, in order to highlight the intensity change of the image sequence, the algorithm firstly conducts Laplace transform for the reference frame, then select a number of characteristics at the image edge to make block matching with the current frame, calculate and compensate for the rotational movement that may exist finally. Through theoretical analysis and simula-tion, we prove that, as for a mixed translational and rotational motion video sequences, the proposed algorithm can reduce required time for block matching computation ,while improving the accuracy of the electronic image stabilization.展开更多
This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength （ACW（n）） algorithm. Th...This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength （ACW（n）） algorithm. The proposed scheme enhances the compression ratio of the ACW（n） algorithm by dividing the binary sequence into a number of subsequences （s）, each of them satisfying the condition that the number of decimal values （d） of the n-bit length characters is equal to or less than 256. Therefore, the new scheme is referred to as ACW（n, s）, where n is the adaptive character wordlength and s is the number of subsequences. The new scheme was used to compress a number of text files from standard corpora. The obtained results demonstrate that the ACW（n, s） scheme achieves higher compression ratio than many widely used compression algorithms and it achieves a competitive performance compared to state-of-the-art compression tools.展开更多
针对机载设备的BIT系统,提出了一种改进的LMS(Least Mean Squares)算法,该算法主要应用于故障检测和定位方面。通过引入自适应学习率控制、加速收敛和稳定性优化技术手段,该算法能够显著提升BIT系统中的信号处理性能,加快故障检测和定...针对机载设备的BIT系统,提出了一种改进的LMS(Least Mean Squares)算法,该算法主要应用于故障检测和定位方面。通过引入自适应学习率控制、加速收敛和稳定性优化技术手段,该算法能够显著提升BIT系统中的信号处理性能,加快故障检测和定位速度,并提高系统的准确性和稳定性。在故障检测方面,改进的LMS算法可以有效地识别故障信号并进行分类和定位。通过对输入信号进行预处理和模型参数的优化,改进LMS算法能够更准确地捕捉异常信号特征,从而实现对故障的快速检测和定位,提高BIT系统的可靠性和故障诊断能力。同时,改进的LMS算法还应用于BIT系统中的自适应滤波模块,用于消除噪声和滤除干扰信号。通过采用自适应学习率控制和加速收敛技术,改进算法能够智能地调整滤波参数,有效抑制噪声和干扰信号,提高BIT系统对故障信号的识别和定位能力。通过实验验证,改进的LMS算法在机载设备的BIT系统中表现出较好的应用潜力。该算法相比传统LMS算法,在故障检测和定位准确性、故障诊断速度以及系统稳定性方面均取得了显著的改善。展开更多
Signal detection plays an essential role in massive Multiple-Input Multiple-Output(MIMO)systems.However,existing detection methods have not yet made a good tradeoff between Bit Error Rate(BER)and computational complex...Signal detection plays an essential role in massive Multiple-Input Multiple-Output(MIMO)systems.However,existing detection methods have not yet made a good tradeoff between Bit Error Rate(BER)and computational complexity,resulting in slow convergence or high complexity.To address this issue,a low-complexity Approximate Message Passing(AMP)detection algorithm with Deep Neural Network(DNN)(denoted as AMP-DNN)is investigated in this paper.Firstly,an efficient AMP detection algorithm is derived by scalarizing the simplification of Belief Propagation(BP)algorithm.Secondly,by unfolding the obtained AMP detection algorithm,a DNN is specifically designed for the optimal performance gain.For the proposed AMP-DNN,the number of trainable parameters is only related to that of layers,regardless of modulation scheme,antenna number and matrix calculation,thus facilitating fast and stable training of the network.In addition,the AMP-DNN can detect different channels under the same distribution with only one training.The superior performance of the AMP-DNN is also verified by theoretical analysis and experiments.It is found that the proposed algorithm enables the reduction of BER without signal prior information,especially in the spatially correlated channel,and has a lower computational complexity compared with existing state-of-the-art methods.展开更多
当前美国国家标准与技术研究院(National Institute of Standards and Technology,NIST)对后量子密码(Post-Quantum Cryptography,PQC)标准化方案的评估已进入第四轮,位翻转密钥封装(Bit Flipping Key Encapsulation,BIKE)协议是目前被...当前美国国家标准与技术研究院(National Institute of Standards and Technology,NIST)对后量子密码(Post-Quantum Cryptography,PQC)标准化方案的评估已进入第四轮,位翻转密钥封装(Bit Flipping Key Encapsulation,BIKE)协议是目前被评估的四个候选方案之一.在BIKE的密钥生成算法中,多项式乘法作为众多密码系统中特别耗时的操作之一,耗费了大量的时间和面积资源.针对此问题,本文设计了一种基于Karatsuba算法(Karatsuba Algorithm,KA)的无交叠多项式乘法器,可高效实现万级比特位宽的多项式乘法,具有低时延、高性能和面积小的特点.同时,本文将该优化乘法器应用于BIKE密钥生成算法中,并基于现场可编程门阵列(Field Programmable Gate Array,FPGA)对其进行硬件架构实现,改进了原有的紧凑多项式乘法和多项式求逆算法.本文提出的乘法器通过采用不同的操作数位宽,可适应对面积和延时的不同需求.与BIKE原本的设计相比,改进的设计使密钥生成模块的延时减小了36.54%,面积延迟积(Area Delay Production,ADP)减小了10.4%.展开更多
基金The National High Technology Research and Devel-opment Program of China (863Program) (No2006AA01Z263)the National Natural Science Foundation of China (No60496311)
文摘Based on the iterative bit-filling procedure, a computationally efficient bit and power allocation algorithm is presented. The algorithm improves the conventional bit-filling algorithms by maintaining only a subset of subcarriers for computation in each iteration, which reduces the complexity without any performance degradation. Moreover, a modified algorithm with even lower complexity is developed, and equal power allocation is introduced as an initial allocation to accelerate its convergence. Simulation results show that the modified algorithm achieves a considerable complexity reduction while causing only a minor drop in performance.
文摘A computationally efficient soft-output detector with lattice-reduction （LR） for the multiple-input multiple-output （MIMO） systems is proposed. In the proposed scheme, the sorted QR de- composition is applied on the lattice-reduced equivalent channel to obtain the tree structure. With the aid of the boundary control, the stack algorithm searches a small part of the whole search tree to generate a handful of candidate lists in the reduced lattice. The proposed soft-output algorithm achieves near-optimal perfor- mance in a coded MIMO system and the associated computational complexity is substantially lower than that of previously proposed methods.
文摘This paper proposes an electronic image stabilization algorithm based on efficient block matching on the plane. This algorithm uses a hexagonal search algorithm, and uses the bit-planes to estimate and compensate for the translational motion between video sequences at the same time;As for the rotary motion vector generated in the video sequences, in order to highlight the intensity change of the image sequence, the algorithm firstly conducts Laplace transform for the reference frame, then select a number of characteristics at the image edge to make block matching with the current frame, calculate and compensate for the rotational movement that may exist finally. Through theoretical analysis and simula-tion, we prove that, as for a mixed translational and rotational motion video sequences, the proposed algorithm can reduce required time for block matching computation ,while improving the accuracy of the electronic image stabilization.
文摘This paper presents a description and performance evaluation of a new bit-level, lossless, adaptive, and asymmetric data compression scheme that is based on the adaptive character wordlength （ACW（n）） algorithm. The proposed scheme enhances the compression ratio of the ACW（n） algorithm by dividing the binary sequence into a number of subsequences （s）, each of them satisfying the condition that the number of decimal values （d） of the n-bit length characters is equal to or less than 256. Therefore, the new scheme is referred to as ACW（n, s）, where n is the adaptive character wordlength and s is the number of subsequences. The new scheme was used to compress a number of text files from standard corpora. The obtained results demonstrate that the ACW（n, s） scheme achieves higher compression ratio than many widely used compression algorithms and it achieves a competitive performance compared to state-of-the-art compression tools.
文摘针对机载设备的BIT系统,提出了一种改进的LMS(Least Mean Squares)算法,该算法主要应用于故障检测和定位方面。通过引入自适应学习率控制、加速收敛和稳定性优化技术手段,该算法能够显著提升BIT系统中的信号处理性能,加快故障检测和定位速度,并提高系统的准确性和稳定性。在故障检测方面,改进的LMS算法可以有效地识别故障信号并进行分类和定位。通过对输入信号进行预处理和模型参数的优化,改进LMS算法能够更准确地捕捉异常信号特征,从而实现对故障的快速检测和定位,提高BIT系统的可靠性和故障诊断能力。同时,改进的LMS算法还应用于BIT系统中的自适应滤波模块,用于消除噪声和滤除干扰信号。通过采用自适应学习率控制和加速收敛技术,改进算法能够智能地调整滤波参数,有效抑制噪声和干扰信号,提高BIT系统对故障信号的识别和定位能力。通过实验验证,改进的LMS算法在机载设备的BIT系统中表现出较好的应用潜力。该算法相比传统LMS算法,在故障检测和定位准确性、故障诊断速度以及系统稳定性方面均取得了显著的改善。
基金supported by Major Project of Science and Technology Research Program of Chongqing Education Commission of China(Grant No.KJZD-M201900601)China Postdoctoral Science Foundation(Grant No.2021MD703932)Project Supported by Engineering Research Center of Mobile Communications,Ministry of Education,China(Grant No.cqupt-mct-202006)。
文摘Signal detection plays an essential role in massive Multiple-Input Multiple-Output(MIMO)systems.However,existing detection methods have not yet made a good tradeoff between Bit Error Rate(BER)and computational complexity,resulting in slow convergence or high complexity.To address this issue,a low-complexity Approximate Message Passing(AMP)detection algorithm with Deep Neural Network(DNN)(denoted as AMP-DNN)is investigated in this paper.Firstly,an efficient AMP detection algorithm is derived by scalarizing the simplification of Belief Propagation(BP)algorithm.Secondly,by unfolding the obtained AMP detection algorithm,a DNN is specifically designed for the optimal performance gain.For the proposed AMP-DNN,the number of trainable parameters is only related to that of layers,regardless of modulation scheme,antenna number and matrix calculation,thus facilitating fast and stable training of the network.In addition,the AMP-DNN can detect different channels under the same distribution with only one training.The superior performance of the AMP-DNN is also verified by theoretical analysis and experiments.It is found that the proposed algorithm enables the reduction of BER without signal prior information,especially in the spatially correlated channel,and has a lower computational complexity compared with existing state-of-the-art methods.
