Fast algorithms for test optimization of core based 3D SoC

The use of 3D-IC technology has become quite widespread in designing core-based systems-on-chip (SoCs). Concomitantly, testing of cores and inter-layer through-silicon-vias (TSVs) spanning through different layers of 3D chips has become an important problem in the manufacturing cycle. Testing 3D-SoCs is more challenging compared to their 2D counterparts because of the complexity of their design and power management issues. Also, the test procedure demands substantially more power than what is required in the normal functional mode, and hence, stringent thermal constraints during test need to be fulfilled to safeguard future performance and reliability of the chip. Since the overall 3D infrastructure depends on routing layer assignments, core allocation, and the geometry of TSV locations, these parameters should be given due consideration while designing the test-access-mechanism (TAM) that aims for minimizing overall test time satisfying power and TSV constraints. In this paper, we present a three-stage algorithm for reducing the test time in automated post-bond core-based 3D-SoCs, under a set of given constraints on test power, TAM-width, and the number of available TSVs. The proposed algorithm, when run on several ITC-02 SoC benchmarks, outperforms the algorithms presented in earlier work with respect to CPU-time, and additionally, reduces test time in many instances.     

基于TSV绑定的三维芯片测试优化策略

本文提出一种三维片上系统(3D SoC)的测试策略,针对硅通孔(TSV,Through Silicon Vias)互连技术的3D SoC绑定中和绑定后的测试进行优化,由于测试时间和用于测试的TSV数目都会对最终的测试成本产生很大的影响,本文的优化策略在有效降低测试时间的同时,还可以控制测试用的TSV数目,从而降低了测试成本.实验结果表明,本文的测试优化策略与同类仅考虑降低测试时间的策略相比,可以进一步降低约20%的测试成本.     

MP3解码器在AS3310D SoC上的优化

MP3是诸如音乐播放器,移动电话等移动设备上最为流行的高质量音频压缩格式.描述了在SoC芯片AS3310D上,基于通用软件优化技术和芯片上特有的DMA控制器,对MP3软件解码器的优化,最终获得了42.7%性能的提高和38.8%存储空间的节省.     

基于Android的3D空战游戏开发

文章设计并实现了一款基于Android的3D空战游戏。该游戏融入了更新鲜的元素、更完整的剧情、更复杂的机关解谜,这些都使动作类游戏逐渐成为所有类型游戏里面款式最丰富的一种。最终通过测试,该游戏不耗费太多的内存资源、运行十分流畅,又不失3D游戏场景实时变化的美感,给玩家带来较为完美的视觉体验。     

基于博弈论的多基站协作波束成形

为抑制小区间干扰,提出了一种基于博弈论的多基站协作波束成形算法,并将该算法应用于多基站协作通信系统模型。该算法是在已知其他小区策略选择的情况下,最大化自身利益的迭代算法。在此基础上研究了将最大化用户速率问题转化为效用函数优化问题进行求解,然后证明其纳什均衡的存在性和唯一性,最后给出求解纳什均衡的步骤。仿真结果表明,相对于非协作算法,所提算法在期望用户方向上保持较高的增益,同时有效地零陷干扰用户,达到抑制小区间干扰的目的,并且具有很好的收敛性。     

基于博弈的协作路由算法

协作虚拟多输入多输出（VMIMO）传输是一种有效的无线传输性能优化技术。将物理层协作VMIMO技术和网络层路由选择技术相结合,设计跨层VMIMO路由选择方案可以利用VMIMO的分集增益,显著地降低网络传输能耗。如何设计VMIMO协作路由协议抵抗无线网络的自私节点和欺骗行为,保证高数据转发率和低传输能耗成为路由设计中的重大挑战。为了提高自私网络的VMIMO路由性能,提出了一种基于重复路由博弈的VMIMO协作路由算法。该算法将网络划分成多个Group、Group间使用VMIMO传输数据。将Group间路由选择过程建模为重复路由博弈过程。为了提高数据转发的成功率,提出适用度函数评估节点参与数据分组转发的信誉。以此为基础,提出基于适用度的路由选择子算法和路由转发子算法。理论证明所提重复路由博弈可达到帕累托最优。仿真实验结果表明本算法可以促进自私节点相互合作,可获得较高的数据转发率,较好地减少数据传输时延以及能量消耗。     

Design of reconfigurable access wrappers for embedded core based SoC test

Testing of embedded core based system-on-chip (SoC) ICs is a well known problem, and the upcoming IEEE P1500 Standard on Embedded Core Test (SECT) standard proposes DFT solutions to alleviate it. One of the proposals is to provide every core in the SoC with test access wrappers. Previous approaches to the problem of wrapper design have proposed static core wrappers, which are designed for a fixed test access mechanism (TAM) width. We present the first report of a design of reconfigurable core wrappers which allow for a dynamic change in the width of the TAM executing the core test. Analysis of the corresponding scheduling problem indicates that good approximate schedules can be achieved without significant computational effort. Specifically, we derive a O(N/sub C//sup 2/B) time algorithm which can compute near optimal SoC test schedules, where N/sub C/ is the number of cores and B is the number of top level TAMs. Experimental results on benchmark SoCs are presented which improve upon integer programming based methods, not only in the quality of the schedule, but also significantly reduce the computation time.     

Window-based peak power model and Particle Swarm Optimization guided 3-dimensional bin packing for SoC test scheduling

This paper addresses the issue of power-aware test scheduling of cores in a System-on-Chip (SoC). While the existing approaches either use a fixed power value for the entire test session of a core or cycle-accurate power values, the proposed work divides the power profiles of cores into fixed-sized windows. This approach reduces the number of power values to be handled by the test scheduling algorithms while reducing the amount of pessimistic over-estimations of instantaneous power consumption. As a result, the power model can be integrated with more exhaustive meta-search techniques for generating power constrained test schedules. In this paper, the proposed power model has been integrated with a Particle Swarm Optimization (PSO) based 3-dimensional (3-D) bin packing technique to generate test schedules. Experimental results prove the quality of the approach to be high compared to the existing scheduling techniques.     

基于TCG图和模拟退火算法的SoC测试调度

为了降低系统芯片测试成本,需复用IP的测试电路和测试矢量,过去几年已经涌现了许多新型测试结构.测试包和测试轨由于其结构简单,已经广泛应用于系统芯片的测试方案中.但基于测试包和测试轨的测试调度算法复杂度很高,难以获得测试调度的最优解,从而降低了测试效率.本文提出了基于传递闭合图(Transitive Closure Graph)的测试调度表示法,该表示法符合P-admissible准则,使组合优化算法适用于SoC测试调度问题.最后本文用模拟退火算法来优化测试调度,实验结果表明此算法调度的测试时间要比报道的结果都好.     

基于博弈论的QoS协作WSNs路由算法

针对无线传感器网络中各个节点之间通信路由单一、无法充分调动合适的路由节点用于下一跳协作通信而浪费不必要的带宽、时延和能耗,提出一种基于博弈论的QoS协作路由算法(QACR),通过研究各个传感器节点的距离、能耗速度与QoS需求量之间的博弈关系,建立基于QoS需求的博弈模型。将协作通信和路由机制相结合,在博弈模型的理论基础上为中心节点选择一个或者多个中继节点,共同协作将数据包发送至目的地址。仿真验证结果表明,这种方法可以减少节点通信的能量消耗和网络延迟,避免网络由于能耗过快、节点死亡率过高而导致的网络断层或瘫痪,保证网络的可靠性QoS需求。     

基于博弈论的P2P网络研究

在P2P网络中，节点可以根据它们的效用函数来决定是否接受服务。效用函数方法可以作为激励机制，促进节点之间的资源共享和相互提供服务。某个节点从其他节点获得服务的可能性直接同它的效用函数值相联系，并且节点要提高它的效用函数值的唯一方法就是为其他节点提供服务，因为可以最大限度地降低空载现象的发生。     

多传感器资源的非平等博弈分配

空战M4系统需要在同一时间段对多个目标执行多种任务,因此,系统多传感器资源必须向子任务进行分配;同时,各子任务又具有不同的优先权和紧迫度。利用非平等博弈理论,建立多传感器资源的非平等博弈分配模型和分配算法,可以合理有效地解决多传感器管理方案的优化问题。仿真结果验证了该方法的有效性。     

Unity引擎方式下3D对战型游戏的网络设计与开发

Unity是一款拥有极强跨平台能力的游戏引擎。使用其智能的编辑界面、多种资源的支持、跨平台一键部署、可视化角色动画Mecanim和引擎,可以将一键部署到PC,WP,IOS,Android,XBOX等平台。主要介绍了基于Unity引擎的3D对战型游戏的网络部分设计过程,在网络服务器端和客户端如何实现相应系统规划来满足对战型游戏的设计需求,以及在实时性要求较高的网游中怎样采用心跳检测和序列化方式实现有效的数据同步和信息传输进行了实现方案的论述。     

基于博弈论功率控制的串行干扰消除算法

无线网络实现串行干扰消除算法可以提高网络吞吐量,在采用串行干扰消除算法的无线网络系统中,如何控制节点间传输功率使系统效用最大化是一个NP-Hard难题。针对此问题提出非合作博弈算法来解决节点间的传输功率控制,提出了串行干扰消除算法功率控制的非合作博弈,证明了纳什均衡,所提算法可以获得较高的无线网络吞吐量,仿真实验证实了分析结果并展示了算法的优越性。     

基于单片机的嵌入式技术在3D视频游戏中的应用

近年来体感3D视频游戏风靡全球,此设计便是对体感3D视频游戏的一次探索和尝试。游戏由下位机和上位机两部分构成,下位机以C8051单片机为核心设计一个硬件电路,连接嵌入到鱼竿模型中的传感器中,负责采集并处理传感器信息。上位机以Virtools为开发工具,负责视频的输出控制。下位机根据上位机的请求通过串口向上位机传送控制信息,实现玩家通过真实的鱼竿在虚拟的屏幕中钓鱼的过程。     

多用户MIMO系统中基于博弈论的鲁棒性功率分配

针对多用户多输入多输出( MU-MIMO)天线系统,提出了一种基于非合作博弈论的功率分配方案。此博弈模型中,以用户在系统中的信号泄漏噪声比值( SLNR)作为用户功率分配和公平性参数设置的依据,保证用户所期望的服务质量和公平性,并证明了纳什均衡的存在性。其次,考虑信道估计误差的影响,提出了一种基于滑动模型的迭代功率分配控制算法满足所有用户的最小通信质量要求。仿真结果显示此方案在信道误差的情况下,相比现有方案可提高系统吞吐量。     

基于博弈论的门限签名体制分析与构造

为了使门限签名体制更具有普适性,引入了“理性参与人”的概念,将所有参与者视为理性的个体,任何阶段以最大化自身利益为目标。基于博弈论对密钥生成和签名合成阶段各参与者的策略和效用进行了分析,证明了在传统门限签名方案中理性参与者没有动机参与签名,导致无法完成对消息的签名,并提出了理性密钥分发和理性签名合成的解决机制。经分析该方法能更好地满足实际需求。     

基于博弈论的多小区OFDMA系统资源分配

立足于限制条件下实现多小区OFDMA系统容量最大或总传输功率最小的优化问题,比较分析了近年来提出的多种基于博弈论的资源分配算法。分析了纳什均衡点存在和唯一的条件,通过引入定价机制或虚拟裁判机制,使得到的解收敛于纳什均衡点。最后,探讨了联合中继节点或MIMO技术的多小区OFDMA系统资源分配算法,该算法能有效提高频谱效率,将成为未来研究的热点。     

Cooperative caching game based on social trust for D2D communication networks

Content sharing via device‐to‐device (D2D) communications has become a promising method to increase system throughput and reduce traffic load. Due to the characteristic of spectrum sharing in D2D network, confidentiality is becoming a key issue in content transmission. Secure communication in D2D networks is generally guaranteed by a physical‐layer security mechanism. However, this method sacrifices the system transmission rate while ensuring security. Since mobile devices are carried by humans, we can leverage their trust relations to enhance the security of communications. As much, considering the psychology structure and social attributes of mobile users, we build a multidimensional trust evaluation mechanism to evaluate the trust relationship between users, and we pick out the trusted users based on the decision‐theoretic rough sets. By sharing content only between trust users, we can enhance the security of content transmissions without relying on physical‐layer security measures. Meanwhile, content caching is now widely used to improve accessing efficiency and reduce traffic load on cellular networks. However, caching content for other users incurs additional cost, which results in selfish and noncooperative behavior in users. Considering such selfishness, we introduce a cooperative caching game based on multidimensional trust relations to motivate users to cache contents for other devices. In this game, the trust relations and physical distance between two users are considered to formulate the cost function. Furthermore, we introduce an incentive caching algorithm based on social trust to minimize the total cost in the D2D network.     

基于博弈论的D2D通信功率控制算法

针对多D2D通信用户共享蜂窝网络频谱资源中的干扰进行研究,为了减少D2D用户间干扰带来的影响,提出了一种改进的基于博弈论的D2D通信功率控制算法。算法中的博弈者是复用相同频谱资源的多D2D通信用户。建立了博弈模型,并在代价函数中引入代价因子,确定了效用函数,得到参与博弈的D2D用户的最优响应函数。文中对博弈均衡特性进行分析,证明了模型中的策略能够达到稳定状态。通过仿真实验验证了算法的有效性,并且与其他算法对比,证明使用此改进算法的D2D用户吞吐量更大,公平性更高。