基于M A T L A B和F P G A设计及应用

本文主要通过进行分析 FPGA 设计中存在的问题,并提出采用 MATLAB 中的 Fixed-point Toolbox 对 FPGA 测试数据进行分析,并通过具体的实例进行证明,在 FPGA 设计中采用 MATLAB软件能够为 FPGA 的设计带来巨大的方便     

基于MATLAB和FPGA设计及应用

本文主要通过进行分析FPGA设计中存在的问题,并提出采用MATLAB中的Fixed-pointToolbox对FPGA测试数据进行分析,并通过具体的实例进行证明,在FPGA设计中采用MATLAB软件能够为FPGA的设计带来巨大的方便。     

FPGA设计中时钟设计的探讨

在FPGA设计过程中,稳定可靠的时钟是系统稳定可靠的重要条件。探讨了FPGA设计过程中5个不同的时钟设计方案,对这些不同方案的优点、缺点和在设计中需要注意的问题进行了分析,并提出了一些合理建议。有利于FPGA设计人员在较短的时间内掌握FPGA时钟设计技术。     

FPGA器件选型研究

随着现场可编程门阵列FPGA技术的成熟和不断飞速发展,大多数字电路的设计将逐步被FPGA取代。目前,FPGA器件已成为很多数字应用领域的主器件。根据多年的设计经验,在相关应用系统中,FPGA器件选型非常重要,不合理的选型会导致一系列的设计问题,有时甚至会使设计失败。经过深入研究后,将选型中相关注意问题进行了总结,对从事FPGA应用开发的人员有很大的参考价值。     

基于CPLD的FPGA快速动态重构设计

随着FPGA的广泛应用,其实现的功能也越来越多,FPGA的动态重构设计就显得愈发重要。在分析Xilinx VertexⅡPro系列FPGA配置流程、时序要求的基础上,设计了基于CPLD的FPGA快速动态重构方案,实现了同一硬件平台下多个FPGA设计版本的在线动态配置和功能重构,该技术已在工程中成功应用。     

FPGA设计中功耗的分析与仿真

FPGA的应用越来越广泛,随着制造工艺水平的不断提升,越来越高的器件密度以及性能使得功耗因数在FPGA设计中越来越重要。器件中元件模块的种类和数量对FPGA设计中功耗的动态范围影响较大,对FPGA的电源功耗进行了分析,并介绍了如何利用Altera公司的PowerPlay Early Power Estimator这一工具在设计前期尽可能准确地估计功耗并通过估计功耗对硬件设计进行优化选择。     

基于FPGA的直接数字频率合成器设计

本文将FPGA器件和DDS技术相结合,确定了FPGA器件的整体设计方案。笔者利用FPGA器件规模大、设计灵活方便的特点,分析研究了用FPGA器件实现DDS系统的方法,并对其关键技术进行了优化处理,采用流水线结构的相位累加器设计和FPGA内嵌的波形存储器设计,在Quartus II软件中采用基于硬件描述语言（VHDL）的自顶向下的设计方法来完成仿真实验。     

具有串口选控波形的DDS核在FPGA中的实现

文章主要介绍了一种具有串口选控波形的基于FPGA的DDS核的设计与实现方法,通过DDS核可以产生任意波形信号。首先在FPGA中实现了DDS核设计,包括频率控制、相位控制、波形控制以及查表几个模块,FPGA将频率控制字、波形控制整合为地址,然后用该地址实现查表,查表后的数据向DA转换器输出;其次在FPGA中实现了串口通信和DA转换的FPGA控制,而串口主要完成输出波形的选择;最后整个设计通过FPGA开发平台得以验证,结果表明设计是正确有效的。     

一种基于真随机序列和安全散列算法可靠加密FPGA设计的方法

FPGA在定制项目和具有设计重构需求的项目开发中广泛应用,随着硬件设计集成度不断提高,在一个FPGA设计中往往集成多个厂商提供的软核设计(IPCore),IPCore知识产权保护显得尤为重要。提出一种真随机序列与密钥结合,并通过安全散列算法加密验证,实现对FPGA设计中商用IPCore知识产权保护的方法。     

星载环境FPGA软件在轨重加载的一种方法

FPGA在空间系统中已经广泛应用,为了满足系统可靠性和可扩展性的要求,实现FPGA软件的在轨重加载迫在眉睫。根据FPGA的加载配置原理,以Xilinx公司的Virtex-Ⅱ系列FPGA为实例,介绍了FPGA在轨重加载的硬件电路设计以及软件设计。经过实验室测试验证,该设计方法合理可行,满足星载环境下FPGA软件在轨编程及重加载的设计需求。     

面向全可编程网络数据平面的资源优化方法

现有数据平面无法在整体上支持网络功能的创新和演进,因此面向用户可编程的新型网络数据平面技术发展迅速.针对现有可编程数据平面硬件开销过大且缺乏资源优化的问题,从解析器、匹配表、动作执行器三个方面建立了资源开销模型,并分别提出了类型域合并、匹配域偏移量合并、"域-字"拆分合并映射等资源优化方法.基于NetFPGA的仿真结果表明,与现有机制相比,所提方法减小了38%左右的资源开销.     

An Adaptive Multicast Tree with QoS Support for Heterogeneous Recipients

This paper proposes a new protocol called MQ, Multicast with QoS, which supports multimedia group communications with QoS guarantees for heterogeneous recipients. With MQ, while resource reservation is de-coupled from QoS multicast routing, they are integrated in a way to avoid the problem of sender-oriented path determination, a problem that occurs when RSVP is used in conjunction with QoS routing for heterogeneous reservations. Being a truly receiver-oriented and integrated scheme for multimedia multicasting, MQ supports such integration in a robust, scalable and loop-free way, accommodates heterogeneous users with varied QoS, dynamically adjusts QoS trees to improve resource utilization, and benefits from being an integrated mechanism to ensure end-to-end QoS services. We have also conducted simulations to evaluate the performance of MQ. MQ demonstrates its advantages to conventional loosely coupled integration of IP multicasting, resource reservation and QoS routing, in terms of better accommodation of heterogeneous users, higher scalability, lower blocking probability for users to join groups with service guarantee, and more efficient resource utilization to enhance system performance.     

Multicast scheduling with resource fairness constraints

Integration of multicast and unicast data in future radio access networks will be necessary in order to improve the resource efficiency and provide new services. Such integration requires new and efficient resource sharing mechanisms. These mechanisms need to be optimized to provide the best possible trade-off between resource efficiency and fairness. In this article, we consider a case where streaming multicast users are multiplexed together with elastic unicast users on a common time-slotted channel. We derive a system model to study the performance of various resource allocations strategies under proportional and resource fairness constraints. Fairness is directly defined in terms of the users’ utilities rather than of the throughputs they are assigned to. We also describe an extension of the well-known unicast proportional fair scheduler to the multicast scenario. Through extensive simulations we demonstrate the performance of this scheduler for various traffic loads and multicast group sizes.

Resource Management for Broadband Access over Time-Division Multiplexed Passive Optical Networks

Passive optical networks are a prominent broadband access solution to tackle the "last mile" bottleneck in telecommunications infrastructure. Data transmission over standardized PONs is divided into time slots. Toward the end of PON performance improvement, a critical issue relies on resource management in the upstream transmission from multiple optical network units (ONUs) to the optical line terminal (OLT). This includes resource negotiation between the OLT and the associated ONUs, transmission scheduling, and bandwidth allocation. This article provides an overview of the resource management issues along with the state-of-the-art schemes over time-division multiplexed PONs (TDM-PONs). We categorize the schemes in the literature based on their features, and compare their pros and cons. Moreover, we introduce a unified state space model under which all TDM-PON resource management schemes can be evaluated and analyzed for their system level characteristics. Research directions are also highlighted for future studies.     

基于非均衡求解的D2D多复用通信资源块分配算法研究

针对小区内D2D多复用的通信资源块分配问题,该文以一个D2D用户分别复用2个和3个蜂窝为基础,提出基于非均衡求解的D2D多复用模式下的资源块分配方案。利用博弈论将资源块划分问题转化为求解被复用蜂窝用户收益联合最大问题。当纳什均衡解不存在时,分析目标函数特性,在可行域内求解“最优解”,保证对不均衡解处理的最优性;对于均衡解存在的情况,将其取整后作为资源分配方案依据,保持其最优性。通过理论分析及仿真实验表明该算法可以提升系统吞吐率,提高小区通信性能。     

An optimal resource control scheme under fidelity and energy constraints in sensor networks

To control congestion, either the traffic from sources should be “reduced” (traffic controlling) or the available resources should be “increased” (resource controlling). Compared to the wired and other wireless counterparts, wireless sensor networks usually have elastic resource availability, and the applications require a certain level of throughput called fidelity. As a result, resource control strategies cannot only alleviate congestion but also ensure the required fidelity level during congestion by accommodating higher incoming traffic. In this paper, we first attempt to formally define the resource control framework that adjusts the resource provisioning at the hotspot nodes during congestion. In an effort to find the optimal resource control under the fidelity and energy constraints, we present a resource increase and decrease algorithm called Early Increase/Early Decrease (EIED) that tries to adjust the effective channel capacity quickly to suit the incoming traffic volume in an energy-efficient manner, thereby increasing the fidelity level observed by the application. Under the energy-constrained optimization, we prove this algorithm incurs the lowest overhead of energy consumption for the given fidelity level that is required by the application. We also prove that the EIED algorithm performed in a distributed manner also lowers the energy consumption per packet at an end-to-end level. The effectiveness of the EIED algorithm is verified by simulations based on realistic sensor network configurations.

面向众核密码处理器的高效负载均衡技术

工作负载分配不均是制约众核密码平台资源利用率提高的重要因素,动态负载分配可提高平台资源利用率,但具有一定开销;所以更高的负载均衡频率并不一定带来更高的负载均衡增益。因此,该文建立了关于负载均衡增益率与负载均衡频率的数学模型。基于模型,提出一种面向众核密码平台的无冲突负载均衡策略和一种基于硬件作业队列的“可扩展-可移植”负载均衡引擎——“簇间微网络-簇内环阵列”。实验证明:在性能、延时功耗积、资源利用率和负载均衡度方面,该文设计的负载均衡引擎与基于“作业窃取”的软件技术相比平均优化约4.06倍、7.17倍、23.01%和2.15倍;与基于“作业窃取”的硬件技术相比约优化1.75倍、2.45倍、10.2%、和1.41倍;与理想硬件技术相比,密码算法吞吐率平均只降低了约5.67%(最低3%)。实验结果表明该文技术具有良好的可扩展性和可移植性。     

Resource Sharing Combined with Layout Effects in High-Level Synthesis

In deep-submicron designs, the interconnects are equally as or more important than the logic gates. In particular, to achieve timing closure, it is necessary and critical to consider the interconnect delay at an early stage of the synthesis process. It has been known that resource sharing in high-level synthesis is one of the major synthesis tasks which greatly affect the final synthesis/layout results. In this paper, we propose a new layout-aware resource sharing approach to overcome some of the limitations of the previous works in which the effects of layout on the synthesis have never been taken into account or considered in local and limited ways, or whose computation time is excessively large. The proposed approach consists of two steps: (Step 1) We relax the integrated resource sharing and placement into an efficient linear programming (LP) formulation based on the concept of placement space; (Step 2) We derive a feasible solution from the solution obtained in Step 1. Then, we employ an iterative mechanism based on the two steps to tightly integrate resource sharing and placement tasks so that the slack time violation due to interconnect delay (determined by placement) as well as logic delay (determined by resource sharing) should be minimized. From experiments using a set of benchmark designs, it is shown that the approach is effective, and efficient, completely removing the slack time violation produced by conventional methods.     

Application level active network (alan) server management architecture

This paper presents the details of the policy-based security and resource management architecture for Application Level Active Network (alan) servers.alan is an active network architecture which enables deployment of user-customised processes (proxylets), which enhance the existing services or introduce new services to the end-user, on the select group of servers in anip network. The issues of security and resource management in this scenario are of crucial importance so as to efficiently facilitate and control the resource consumption of user-specified processes on the active servers, as well as to protect the server platforms from unauthorised proxylet deployment or malevolent behaviour. The architecture allowing efficient resource and security control is presented in this paper, including detaileduml diagrams capturing the management functionality, as well as a set of concrete management policies for thealan scenario. The examplexml policies are also given, and the deployment of this architecture in real-life trials is described. This development forms a part of a larger management architecture foralan-enabled networks developed in the context of theist projectandroid (Active Network DistRibuted Open Infrastructure Development).     

Blocking in a Shared Resource Environment

In recent years, considerable effort has focused on evaluating the blocking experienced by "customers" in contending for a commonly shared "resource." The customers and resource in question have typically been messages and storage space in message storage applications or data streams and bandwidth in data multiplexing applications. The model employed in these studies, a multidimensional generalization of the classical Erlang loss model, has been limited to exponentially distributed storage (or data transmission) times, questions concerning efficient computational schemes have largely been ignored, and the class of resource sharing policies considered has been unnecessarily restricted. The contribution of this paper is threefold. We first show that the state distribution (obtained by previous authors) is valid for the large class of residency time distributions which have rational Laplace transforms. Second, we show that, for the important and commonly implemented policy of complete sharing, a simple one-dimensional recursion can be developed which eliminates all difficulty in computing quantities of interest-regardless of both the size and dimensionality of the underlying model. Third, we show that the state distribution holds for completely arbitrary resource sharing policies.