共查询到20条相似文献,搜索用时 171 毫秒
1.
2.
针对极化码SC译码器存在的高延时、低吞吐率、低资源效率等问题,文中提出了一种高性能SC译码器硬件架构。通过剪枝冻结比特结点的方式化简SC译码二叉树,设计跨周期的PE单元存储模块,并在译码最后一个阶段利用2b-SC算法,保证译码器具有较低的延时和较高的吞吐率。采用资源复用的方法,提高译码器资源效率。测试结果表明,文中所提出的译码器周期为330,吞吐率为388.85 Mbit·s-1,资源效率为2.204 Mbit·s-1·kGE-1。与其他SC译码器的对比试验表明,该高性能SC译码器的延时、吞吐率、资源效率均得到了有效改善。此外,该译码器的功耗较低,应用前景良好。 相似文献
3.
4.
针对RFID传统算法一次只能识别一个标签、吞吐率低、饿死率高的不足,文中提出一种RFID系统防碰撞算法,即利用伪ID码分组,并应用标签可并行识别技术的防碰撞算法(PILD算法)。PILD算法利用伪ID码对待识别标签进行分组,当出现碰撞现象时,运用并行识别算法对出现碰撞的标签进行识别。该算法能避免因帧长过大造成吞吐率下降的问题,并提高RFID识别技术的吞吐率。首先对PILD算法的识别过程进行理论分析,再运用Mathematica软件对PILD算法进行仿真。理论分析及仿真结果表明:当标签总数为2 000,单次碰撞标签数小于等于6时,标签平均查询次数近似为1.26次;该算法的吞吐率较稳定且达到0.791 092,与基于伪ID码的树型防碰撞算法和Logistic-DFSA算法相比,所提算法吞吐率分别提高28.82%、4.74%;当标签数大于1 400时,PILD算法的标签总查询次数最少,标签平均查询次数最少。所提算法中伪ID码分组能够减少单个标签因多次碰撞发生“饿死现象”的概率,与基于伪ID码的树型防碰撞算法和Logistic-DFSA算法相比,PILD算法饿死率最低。 相似文献
5.
6.
固定角度旋转的CORDIC(Coordinate Rotation Digital Computer)算法已经广泛的应用于高速数字信号处理、图像处理、机器人学等领域.针对固定角度旋转CORDIC算法在相位旋转过程中,存在数据吞吐率较高、占用硬件资源较多且资源消耗量大等缺点,提出了利用混合CORDIC算法,将角度旋转分为单向角度旋转和一次角度估计旋转两部分.本文根据欠阻尼理论,将固定角度旋转采用单向旋转CORDIC算法实现,减少了流水线的级数和迭代符号位的判决,然后通过对角度估计旋转的二进制表示,修正常数因子,再根据角度映射关系进行相关处理,完成高速高精度坐标旋转.最后在硬件平台上进行了仿真实验.实验结果表明,在误差范围一定的前提下,混合算法进一步的减少了迭代次数,并且资源消耗较低,提高了数据吞吐率. 相似文献
7.
文中介绍的系统综合了诺威网多用户操作系统、分布式处理、并行处理、关系式数据库等最新技术,并结合无线寻呼业务的特点开发出的高效、稳定、经济效益高,中文、数字兼用(通用)的新寻呼系统。它采用了分布处理原理,系统处理速度快、吞吐率高。系统容量可达30万门。可从最小容量5000门,像搭积木那样逐步扩充到最大容量。它具有监视功能,可监视话务员工作及信息流。还配有语音自动应答选件。可减轻话务员的劳动。系统的性能/价格比优于小型机组成的系统。适用于小型到大型的各种半自动数字、中文寻呼系统。 相似文献
8.
物联网已被广泛应用于各行各业。在智慧医疗、智能制造等应用领域,物联网设备采集的数据与用户隐私甚至生命财产安全关系密切。为了保障数据的机密性和完整性,防止数据篡改或泄露,以RFC 8998公布的认证加密算法SM4-CCM为对象,研究和设计了一种低功耗的SM4-CCM算法硬件架构。在TSMC 90nm工艺、1.0V供电电压下的实验结果显示,该设计的功耗仅为1.338mW,面积为31.4K门,而吞吐率达到32.12 Mbps@100MHz。实验结果表明,该设计的功耗、面积、吞吐率等性能指标能够满足物联网数据保护需求。 相似文献
9.
物联网已被广泛应用于各行各业。在智慧医疗、智能制造等应用领域,物联网设备采集的数据与用户隐私甚至生命财产安全关系密切。为了保障数据的机密性和完整性,防止数据篡改或泄露,以RFC 8998公布的认证加密算法SM4-CCM为对象,研究和设计了一种低功耗的SM4-CCM算法硬件架构。在TSMC 90 nm工艺、1.0 V供电电压下的实验结果显示,该设计的功耗仅为1.338 mW,面积为31.4 K门,而吞吐率达到32.12 Mbps@100 MHz。实验结果表明,该设计的功耗、面积、吞吐率等性能指标能够满足物联网数据保护需求。 相似文献
10.
提出了一种基于分组自适应多叉树的RFID防碰撞算法,该算法将标签分为多组并按分组处理标签,减少同一时刻同时响应的标签的数目,从而减少碰撞发生的概率,对同一分组的标签,按照碰撞因子自动选择动态二叉树或动态四叉树搜索,同时采用后退策略。仿真结果表明,该算法在平均查询次数及传输数据量上较其他算法都有较大提高. 相似文献
11.
12.
Fedotov A. Ryabko B. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2001,47(1):326-329
The problem of constructing a binary search tree for a set of binary words has wide applications in computer science, biology, mineralogy, etc. Shannon considered a similar statement in his optimal coding theorem. It is NP-complete to construct a tree of minimum cost; therefore, the problem arises of finding simple algorithms for constructing nearly optimal trees. We show that there is a simple algorithm for constructing search trees sufficiently close to the optimal tree on average. By means of this algorithm we prove that for the optimal tree the average number of bits to be checked is near to its natural lower bound, i.e., the binary logarithm of the number of given words: their difference is less than 1.04 相似文献
13.
用户分组算法作为非正交多址接入(NOMA)的关键部分,对系统吞吐量和用户公平性具有重要影响。当用户数量和可用的资源增加时,用户分组的最佳调度将变得不可行,该文提出一种子带间多用户分组优化算法。该算法首先根据用户信道增益差异和子带复用用户数限制条件进行多用户初始分组处理,减小用户搜索空间,然后逐步完成初始分组用户间的优化组合,以几何平均用户吞吐量最大为用户分组准则,进一步提升小区边缘用户的吞吐量。仿真结果表明,所提算法与传统的用户分组算法相比,系统总吞吐量和几何平均用户吞吐量性能提升均超过3%。 相似文献
14.
基于决策树的分组分类算法因易于实现和高效性,在快速分组分类中广泛使用。决策树算法的基本目标是构造一棵存储高效且查找时间复杂度低的决策树。设计了一种基于规则集统计特性和评价指标的决策树算法——HyperEC 算法。HyperEC算法避免了在构建决策树过程中决策树高度过高和存储空间膨胀的问题。HyperEC算法对IP地址长度不敏感,同样适用于IPv6的多维分组分类。实验证明,HyperEC算法当规则数量较少时,与HyperCuts基本相同,但随着规则数量的增加,该算法在决策树高度、存储空间占用和查找性能方面都明显优于经典的决策树算法。 相似文献
15.
We study online multicasting in WDM networks with shared light splitter bank. Our objective is either to maximize the network
throughput or to minimize the blocking probability. Due to the nature of dynamic requesting for network resources by online
multicast requests, the network usually is unable to allocate the resources needed for each request in advance. Instead, it
either accepts the request by building an economic multicast tree for the request, in terms of the utilization of the network
resources if it has sufficient resources available, or rejects the request, otherwise. It is desirable that the cost of realizing
each multicast request be minimized, and the network throughput will be maximized ultimately through the cost saving on each
individual request. Since optical light splitting and wavelength conversion switching in optical networks is cost expensive
and its fabrication is difficult, it is assumed that only a limited number of light splitters and wavelength converters are
installed at a node, which will be shared by all the incoming signals at the node. In addition, it is further assumed that
only a fraction of nodes in the network are installed with such optical switches. In this article we first propose a cost
model for realizing an online multicast request under such network environments with limited light splitters and wavelength
converters, which models the cost of utilization of network resources, particularly in modeling the light splitting and wavelength
conversion ability at nodes. We then show that finding a cost-optimal multicast tree for a multicast request under the proposed
cost model is NP-complete, and instead devise approximation and heuristic algorithms for it. We finally conduct experiments
to evaluate the performance of the proposed algorithms. The results show that the proposed algorithms are efficient and effective
in terms of network throughput.
相似文献
Weifa LiangEmail: |
16.
A method based on recursive computation of the expected number of attempts and successes during the collision resolution phase of an access control algorithm is introduced for the design of near-optimum control strategies for multiple access collision channels with ternary and binary feedback. With this approach it is possible to circumvent the extremely difficult and still unsolved problem of finding the access control algorithm which achieves the highest throughput by settling for a near-optimum solution. The key to the design of the algorithms is to approximate the originally infinite-dimensional optimization problem by a one-dimensional optimization problem. In the ternary feedback case, the proposed algorithm achieves a throughput virtually identical to the highest throughput reported. Several forms of binary feedback are considered, and algorithms are introduced that achieve the highest throughput reported 相似文献
17.
18.
An analysis is made of the throughput and delay performance of two classes of free-access tree algorithms with minislots. In one class, binary feedback information is available in minislots, and in the other, ternary feedback information is available. It is shown that the highest maximum throughput 0.56714 is achieved in the limiting case where the number of minislots in a (large) slot is infinity and minislot overhead is zero. A lower bound of the average transmission delays in these algorithms is analytically derived. The obtained lower bound is also a lower bound of the average delay of the whole class of the free-access algorithms 相似文献
19.
IEEE 802.16 wireless MAN standard specifies the air interface of broadband wireless access systems providing multiple services.
In the wireless MAN, the best effort service class is ranked on the lowest position in priority and is assisted by a MAC scheme
based on reservation ALOHA. In such a MAC scheme, a collision of resource requests is unavoidable so that the wireless MAN
standard adopted a truncated binary exponential back-off scheme to arbitrate request attempts. While an exponential back-off
scheme is simple to implement, its capture or starvation effect was revealed to deteriorate the fairness in short-term throughput
and delay variance in the long term. Aiming at improving the throughput and delay performance, we thus propose the unisource
and multisource m-ary tree schemes as alternatives for resolving request collisions in a wireless MAN. For the unisource tree scheme, we first
develop an analytical method to exactly calculate the throughput in the saturated environment. Using the analytical method
and simulation method as well, we then evaluate the saturated throughput, mean of MAC PDU delay and variance of MAC PDU delay
in each proposed scheme. From the numerical examples, we confirm that the unisource and multisource m-ary tree schemes invoke superior throughput and delay performance to a truncated binary exponential back-off scheme. 相似文献
20.
In this paper, we propose a mechanism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism includes two novel algorithms: a source-based multicast tree topology construction algorithm followed by an interference-aware multicast scheduling algorithm. The proposed multicast interfer-ence-aware scheduling algorithm can be ap-plied to both source-based and rendez-vous-based multicast tree topologies. Results of our simulation study show that in compari-son to the mechanism used for the IEEE 802.16’s standard, the proposed multicast tree generation algorithm reduces the number of consumed mini-slots by 64% on average. Moreover, using the proposed interfer-ence-aware scheduling algorithm decreases the number of required mini-slots by a further 22% on average. Therefore, the proposed multicast scheduling mechanism shows a higher throughput than the previous ap-proaches and it is more scalable with respect to increasing the number of multicast groups as well as increasing the number of members inside each multicast group. 相似文献