检索结果-内蒙古大学图书馆

Radio resource allocation for multi-antenna gateway stations of diverse NGSO constellation networks

IET COMMUNICATIONS 2022年第7期16卷 734-744页

作者： Ren, Zixuan Li, Wei Jin, Jin Zhan, Yafeng Tsinghua Univ Beijing Natl Res Ctr Informat Sci & Technol Beijing Peoples R China Tsinghua Univ Sch Aerosp Engn Beijing Peoples R China MIIT State Radio Monitoring Ctr Beijing Peoples R China

With the rapid development of NGSO satellite constellation, multi-antenna gateway station has become a trend to increase the capacity of communication system. Since the wide use of Ku/Ka bands as well as the dynamic characteristics of NGSO networks, the co-frequency interference between constellations is inevitable, and the interference limits become important constraints to the system capacity of multi-antenna gateway stations. In this paper, the allocation of radio resources, including power and beam, under the interference constraints is formulated as an optimization problem. However, traditional optimization methods may not be suitable for NGSO satellite coexistence scenarios due to the fast movements of NGSO satellites. In order to address this problem, the optimization problem is transformed into two subproblems, and a Jensen's Inequality-based Fast Iteration (JI-FI) algorithm is designed to solve both of them iteratively. Simulation results show that the interference can be effectively reduced to the value below the threshold and beam and power resources can be allocated simultaneously by adopting the proposed algorithm. Compared with the traditional methods, the proposed scheme can significantly improve the system capacity by more than 25%, and it can greatly reduce the computational complexity.

关键词： iterative methods NGSO satellite constellation optimization problem resource allocation co-frequency interference optimisation satellite antennas diverse NGSO constellation networks radio resource allocation JI-FI algorithm multiantenna gateway station microwave antenna arrays interference constraints computational complexity power resources Jensen's inequality-based fast iteration algorithm NGSO satellite coexistence scenarios radiofrequency interference

来源：评论

学校读者我要写书评

暂无评论

Complementary peak reducing signals for TDCS PAPR reduction

引用

IET COMMUNICATIONS 2017年第6期11卷 961-967页

作者： Chang, Cheng Huan, Hao Guo, Jianmin Tao, Ran Beijing Inst Technol Coll Informat & Elect Beijing 100081 Peoples R China Beijing Key Lab Fract Signals & Syst Beijing 100081 Peoples R China

Transform domain communication systems (TDCSs) are cognitive anti-interference multi-carrier communication systems with dynamic spectrum access. The inherent high peak-to-average power ratio (PAPR) of TDCS reduces the efficiency of the power amplifier. Adaptive waveform generation of the TDCS also causes the PAPR to vary according to the spectral conditions on hand. In this study, a complementary peak reducing signal (CPRS) method is proposed and analysed. It uses all unoccupied frequency bins to transmit data and uses all interfered frequency bins to generate CPRSs. Every data signal and its corresponding CPRS are orthogonal and complementary, so as to fully occupy all frequency bins. Therefore, the PAPR reduction of the composite signal with all frequency bins is considered. Once the optimal pseudo-random phase sequence is determined, the sequence can adapt to all spectral conditions without side information, and the computational complexity for diverse spectral conditions is greatly reduced. Moreover, the orthogonality between the data signal and its CPRS in the frequency domain eliminates distortions and spectral spreading. As a component of the transmitting signal, CPRS may cause bit error rate (BER) loss. This study also proposes a signal power adjustment mechanism to achieve a compromise between PAPR reduction and BER loss.

关键词： error statistics radio spectrum management computational complexity complementary peak reducing signals TDCS PAPR reduction transform domain communication systems cognitive antiinterference multi-carrier communication systems dynamic spectrum access peak-to-average power ratio TDCS power amplifier complementary peak reducing signal computational complexity bit error rate BER loss

来源：评论

学校读者我要写书评

暂无评论

Video Encoding Acceleration in Cloud Gaming

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2015年第12期25卷 1975-1987页

作者： Semsarzadeh, Mehdi Yassine, Abdulsalam Shirmohammadi, Shervin Univ Ottawa Distributed & Collaborat Virtual Environm Res Lab Ottawa ON K1N 6N5 Canada Istanbul Sehir Univ TR-34662 Istanbul Turkey

Cloud computing provides reliable, affordable, and flexible resources for many applications and users with constrained computing resources and capabilities. The cloud computing concept is becoming an appealing paradigm for many industries including the gaming industry, leading to the introduction of cloud gaming architectures. Despite its advantages, cloud gaming suffers from unguaranteed end-to-end delay as well as server side's computational complexity. In this paper, a novel algorithm for reducing the computational complexity and hence speeding up the video encoding speed is proposed. Specifically, by performing minimum modifications in the game engine and the video codec, some information from the game engine is fed into the video encoder to bypass the motion estimation (ME) process. Our results show that the proposed method achieves up to 39% speedup in the ME process, leading to a 24% acceleration in the total encoding process.

关键词： Cloud computing cloud gaming computational complexity game video motion estimation (ME) video encoding

来源：评论

学校读者我要写书评

暂无评论

Lattice-valued fuzzy Turing machines: Computing power, universality and efficiency

引用

FUZZY SETS AND SYSTEMS 2009年第23期160卷 3453-3474页

作者： Li, Yongming Shaanxi Normal Univ Coll Comp Sci Xian 710062 Peoples R China

In this paper we study fuzzy Turing machines with membership degrees in distributive lattices, which we called them lattice-valued fuzzy Turing machines First we give several formulations of lattice-valued fuzzy Turing machines. including in particular deterministic and non-deterministic lattice-valued fuzzy Turing machines (l-DTMcs and l-NTMs). We then show that l-DTMcs and l-NTMs are not equivalent as the acceptors of fuzzy languages. This contrasts sharply with classical Turing machines Second, we show that lattice-valued fuzzy Turing machines can recognize n-re sets in the sense of Bedregal and Figueira, the super-computing power of fuzzy Turing machines is established in the lattice-setting Third, we show that the truth-valued lattice being finite is a necessary and sufficient condition for the existence of a universal lattice-valued fuzzy Turing machine. For an infinite distributed lattice with a compact metric, we also show that it universal fuzzy Turing Machine exists in an approximate sense. This means. for any prescribed accuracy, there is a universal machine that can simulate any lattice-valued fuzzy Turing machine on it with the given accuracy Finally. we introduce the notions of lattice-valued fuzzy polynomial time-bounded computation (IP) and lattice-valued non-deterministic fuzzy polynomial time-bounded computation (INP), and investigate their connections with P and NP We claim that lattice-valued fuzzy Turing machines are more efficient than classical Turing machines. (C) 2009 Elsevier B.V All rights reserved

关键词： Fuzzy systems model Fuzzy Turing machine Recursively enumerable language Recursive language Universal machine computational complexity

来源：评论

学校读者我要写书评

暂无评论

Localisation of mixed near-field and far-field sources using the largest aperture sparse linear array

引用

IET SIGNAL PROCESSING 2018年第2期12卷 155-162页

作者： Ebrahimi, Ali Akbar Abutalebi, Hamid Reza Karimi, Mahmood Yazd Univ Dept Elect Engn Yazd Iran Shiraz Univ Sch Elect & Comp Engn Shiraz Iran

In some applications, the signals received by an array are a mixture of signals emitted by both far-field and near-field sources. This study develops a new cumulant-based multiple signal classification (MUSIC) algorithm for source localisation using a new structural sparse array for scenarios where both far-field and near-field sources coexist. The key feature of this algorithm is that it utilises fourth-order cumulants to compute the virtual covariance matrix and constructs a new special cumulant matrix to acquire the largest number of virtual sensors and the largest array aperture for a given number of sensors. The authors provide a geometric proof to justify the utilisation of the proposed sparse linear array and compute the effective aperture of the array. The proposed algorithm increases resolution ability, direction of arrival (DOA) and range estimation accuracy, and the number of sources to be localised. Moreover, the new method has the main advantage that it does not use the information of all sensors;so that it provides somewhat low computational complexity while it uses many actual and virtual sensors. Monte Carlo simulations are provided to demonstrate the effectiveness of the proposed method.

关键词： signal classification covariance matrices direction-of-arrival estimation Monte Carlo methods higher order statistics largest aperture sparse linear array cumulant-based multiple signal classification algorithm source localisation structural sparse array virtual covariance matrix direction of arrival estimation range estimation accuracy computational complexity Monte Carlo simulations

来源：评论

学校读者我要写书评

暂无评论

Simultaneous optimisation of dynamic power, area and delay in behavioural synthesis

引用

IEE PROCEEDINGS-COMPUTERS AND DIGITAL TECHNIQUES 2000年第6期147卷 383-390页

作者： Williams, AC Brown, AD Zwolinski, M Univ Southampton Dept Elect & Comp Sci Southampton SO17 1BJ Hants England

Concern over power dissipation, coupled with the continuing rise in system size and complexity, means that there is a growing need for high-level design tools capable of doubt automatically optimising systems to take into account power dissipation, in addition to the more conventional metrics of area, delay and testability. Current methods for reducing power consumption tend to be ad-hoc: for example, slowing down. or turning off idle parts of the system, or a controlled reduction in power supply The behavioural synthesis system described here features an integrated incremental power estimation capability, which makes use of activity profiles, generated automatically through simulation of a design on any standard VHDL simulator;accurate circuit-level cell models (generated, again automatically, via SPICE simulation);and a comprehensive system power model. This data, along with similar estimators for. area and delay, guides the optimisation of a design towards independent user-specified objectives for final area, delay, clock speed, and energy consumption. Tn addition, a range of power reducing features are included, encompassing: supply voltage scaling, clock gating, input latching, input gating, low-power cells, and pipelined and multicycle units. These are automatically exploited during optimisation as part of the area/delay/power dissipation trade-off process. The resulting system is capable of reducing the estimated energy consumption of several benchmark designs by factors of between 3.5 and 7.0 times. Furthermore, the design exploration capability enables a range of alternative structural implementations to be generated from a single behavioural description, with differing art area/dealy/power trade-offs.

关键词： SPICE High level languages SPICE simulation activity profiles Hardware-software codesign VHDL simulator computational complexity area behavioural synthesis Digital circuit design, modelling and testing complexity dynamic power circuit-level cell models Computer-aided circuit analysis and design Semiconductor integrated circuit design, layout, modelling and testing simultaneous optimisation testability hardware description languages delay high-level design tools integrated incremental power estimation Electronic engineering computing design exploration Formal methods circuit complexity circuit layout CAD

来源：评论

学校读者我要写书评

暂无评论

Memory Feature-Based Sample Selection Strategy for Few-Sample Learning Digital Predistortion

引用

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2023年第2期71卷 602-612页

作者： Yang, Guichen Qiao, Wen Jiang, Chengye Su, Lei Han, Renlong Tan, Jingchao Liu, Falin Univ Sci & Technol China Dept Elect Engn & Informat Sci Hefei 230026 Peoples R China

This article proposed a novel sample selection strategy for reducing the computational complexity of digital predistortion (DPD). Due to the memory effect of the power amplifier (PA), the PA's output is affected by the memory term. Thus, unlike existing sample selection methods (SSMs) that consider signal amplitude as the only feature, the proposed method regards signal points and their lagged terms (memory terms) as features of each sample point. We also introduce representative subset selection methods to further increase the selected samples' diversity, and these methods are improved to reduce their storage and computational complexity. By expanding the diversity among the selected samples, even a few samples for training can obtain satisfactory performance. In addition, the complexity analysis shows that the proposed method is effective and competitive. Based on the experimental results, the proposed method outperforms the existing techniques in performance, complexity, and stability.

关键词： computational complexity Training computational modeling Behavioral sciences Parameter extraction Predistortion Monte Carlo methods Behavioral modeling digital predistortion (DPD) few-sample learning (FSL) power amplifiers (PAs) sample selection method (SSM)

来源：评论

学校读者我要写书评

暂无评论

Coherence in finite argument systems

引用

ARTIFICIAL INTELLIGENCE 2002年第1-2期141卷 187-203页

作者： Dunne, PE Bench-Capon, TJM Univ Liverpool Dept Comp Sci Liverpool L69 7ZF Merseyside England

Argument Systems provide a rich abstraction within which divers concepts of reasoning, acceptability and defeasibility of arguments, etc., may be studied using a unified framework. Two important concepts of the acceptability of an argument p in such systems are credulous acceptance to capture the notion that p can be 'believed';and sceptical acceptance capturing the idea that if anything is believed, then p must be. One important aspect affecting the computational complexity of these problems concerns whether the admissibility of an argument is defined with respect to 'preferred' or 'stable' semantics. One benefit of so-called 'coherent' argument systems being that the preferred extensions coincide with stable extensions. In this note we consider complexity-theoretic issues regarding deciding if finitely presented argument systems modelled as directed graphs are coherent. Our main result shows that the related decision problem is Pi(2)((p)) complete and is obtained solely via the graph-theoretic representation of an argument system, thus independent of the specific logic underpinning the reasoning theory. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： argument systems coherence credulous reasoning sceptical reasoning computational complexity

来源：评论

学校读者我要写书评

暂无评论

A low-memory intensive decoding architecture for double-binary convolutional turbo code

引用

TURKISH JOURNAL OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCES 2014年第1期22卷 202-213页

作者： Zhan, Ming Zhou, Liang Wu, Jun Univ Elect Sci & Technol China Natl Key Lab Sci & Technol Commun Chengdu 610054 Peoples R China Southwest Univ Sch Elect & Informat Engn Chongqing Peoples R China Waseda Univ Global Informat & Telecommun Inst Tokyo Japan

Memory accesses take a large part of the power consumption in the iterative decoding of double-binary convolutional turbo code (DB-CTC). To deal with this, a low-memory intensive decoding architecture is proposed for DB-CTC in this paper. The new scheme is based on an improved maximum a posteriori probability algorithm, where instead of storing all of the state metrics, only a part of these state metrics is stored in the state metrics cache (SMC), and the memory size of the SMC is thus reduced by 25%. Owing to a compare-select{recalculate processing (CSRP) module in the proposed decoding architecture, the unstored state metrics are recalculated by simple operations, while maintaining near optimal decoding performance.

关键词： Branch metrics computational complexity MAP algorithm state metrics cache

来源：评论

学校读者我要写书评

暂无评论

Tracking-DOSeqSLAM: A dynamic sequence-based visual place recognition paradigm

引用

IET COMPUTER VISION 2021年第4期15卷 258-273页

作者： Tsintotas, Konstantinos A. Bampis, Loukas Gasteratos, Antonios Democritus Univ Thrace Sch Engn Dept Prod & Management Engn Lab Robot & Automat Xanthti Greece

Simultaneous localization and mapping (SLAM) refers to a process that permits a mobile robot to build up a map of the environment and, at the same time, to use it to compute its location. One of its most important components is its ability to associate the most recently perceived visual measurement to the one derived from previsited locations, a technique widely known as loop closure detection. In this article, we evolve our previous approach, dubbed as `DOSeqSLAM' by presenting a low complexity loop closure detection pipeline wherein the traversed trajectory (map) is represented by sequence-based locations (submaps). Each of these groups of images, referred to as place, is generated online through a point tracking repeatability check employed on the perceived visual sensory information. When querying the database, the proper candidate place is selected and, through an image-to-image search, the appropriate location is chosen. The method is subjected to an extensive evaluation on seven publicly available datasets, revealing a substantial improvement in computational complexity and performance over its predecessors, while performing favourably against other state-of-the art solutions. The system's effectiveness is owed to the reduced number of places, which, compared to the original approach, is at least one order of magnitude less.

关键词： robot vision point tracking repeatability check previsited locations mobile robot mobile robots recently perceived visual measurement traversed trajectory dynamic sequence-based visual place recognition paradigm appropriate location map image-to-image search computational complexity DOSeqSLAM path planning sequence-based locations proper candidate place perceived visual sensory information low complexity loop closure detection pipeline image sequences SLAM (robots)

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：