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61.
建立了一种应用于基于RFID(无线射频识别)的单件生产实验系统的四自由度机械手控制的Petri网模型,给出了其控制方法,使其能完成零件的拾取和搬运的动作,从而实现对各加工任务的调度。  相似文献   
62.
在对UHF RFID读写器工作原理进行分析的基础上,介绍一种工作在UHF频段下的读写器的射频接口电路,并确定读写器的解调方式,重点对正交零中频解调方式进行研究,并给出读写器的实现方案.  相似文献   
63.
介绍了一种将只读射频标签和EPC-64I码应用于邮政总包处理中的方案,它可提高邮政总包的流通效率和增加邮政部门的经济效益。文章结合邮政总包生产作业特点的基础上选择了射频频率和标签类型,进行了编码和射频标签外部设计,构建了RFID应用网络系统框架,简要说明了标签的回收利用和信息注销,并对现场应用RFID的具体操作以及效果做了分析。  相似文献   
64.
A bewildering number of proposals have offered solutions to the privacy problems inherent in RFID communication. This article tries to give an overview of the currently discussed approaches and their attributes.
Marc LangheinrichEmail:
  相似文献   
65.
Robust DOA estimation and target docking for mobile robots   总被引:1,自引:1,他引:0  
Direction of arrival (DOA) guided automated target acquisition and docking system is proposed for mobile robots employing the dual-directional antenna system. The dual-directional antenna estimates the DOA of the signal of interest using the ratio of the signal strengths between two adjacent antennas. In practice, DOA estimation poses a significant technical challenge, since the RF signal is easily distorted by the environmental conditions. Therefore, the robot often loses its way in an electromagnetically disturbed environment. To cope with this problem, a robust DOA estimation algorithm is developed based on Kalman filtering. This algorithm allows the robot to reduce the potential error in the estimated DOA, and adjust the robot’s heading to the target transponder without needing to know the positions of current and previous measurements in a global coordinate system. The simulation and experiment results clearly demonstrate that the mobile robot equipped with the developed system is able to dock to a target transponder in an indoor environment partially occupied by obstacles.  相似文献   
66.
RFID标签防碰撞研究   总被引:2,自引:0,他引:2  
分别简要介绍了几种ALOHA算法与树形算法,并对ALOHA算法与树形算法作了简要的比较。同时详细介绍了具有一定自学习能力的"在时隙内利用贝叶斯更新的帧ALOHA"算法与"自适应二进制分裂(ABS)"算法。  相似文献   
67.
低频唤醒技术在微功耗主动式RFID中的应用研究   总被引:1,自引:1,他引:0  
微功耗主动式RFID系统的标签一般采用纽扣电池供电,其功耗是一个很关键的问题,目前常采用定时唤醒的工作方式,本文介绍了低频唤醒技术的实现原理,并讨论了将其应用到微功耗主动式RFID系统中解决射频标签内发射模块的功耗问题,给出了低频唤醒的关键电路和程序流程,实践证明该方案可以很好地解决主动式RFID的功耗问题.  相似文献   
68.
The safety of patients and the quality of medical care provided to them are vital for their wellbeing. This study establishes a set of RFID (Radio Frequency Identification)-based systems of patient care based on physiological signals in the pursuit of a remote medical care system. The RFID-based positioning system allows medical staff to continuously observe the patient's health and location. The staff can thus respond to medical emergencies in time and appropriately care for the patient. When the COVID-19 pandemic broke out, the proposed system was used to provide timely information on the location and body temperature of patients who had been screened for the disease. The results of experiments and comparative analyses show that the proposed system is superior to competing systems in use. The use of remote monitoring technology makes user interface easier to provide high-quality medical services to remote areas with sparse populations, and enables better care of the elderly and patients with mobility issues. It can be found from the experiments of this research that the accuracy of the position sensor and the ability of package delivery are the best among the other related studies. The presentation of the graphical interface is also the most cordial among human-computer interaction and the operation is simple and clear.  相似文献   
69.
为了解决传统RFID定位技术中存在的定位精度差和电子标签功耗高这2个问题,提出了一种基于低频触发的2.4GHz高精度区域定位系统的设计方案。该方案将低频125kHz触发信号与2.4GHz射频信号相结合,采用低频唤醒的方法极大降低了电子标签的功耗,利用可调节触发距离的触发机制将RFID系统的定位精度进一步提高.基于该方案设计了2.4GHz有源电子标签、125kHz触发器和2.4GHz阅读器三个子系统。阅读器与触发器的分离式设计,节约了铺设成本。系统硬件电路设计中加入了可调电位器和数字电压调节器,分别对识别距离和触发距离进行调节,使设备的配置更为方便,增强了系统的实用性。测试数据显示,阅读器与标签的最大通信距离长达120m,有源电子标签的待机时间约为2a(年),RFID定位系统能够实现1~5.2m的可调定位精度。测试结果验证了该方案的有效性。  相似文献   
70.
Recent research has demonstrated the potential benefits of radio frequency identification (RFID) technology in the supply chain and production management via its item-level visibility. However, the RFID coverage performance is largely impacted by the surrounding environment and potential collisions between the RFID devices. Thus, through RFID network planning (RNP) to achieve the desired coverage within the budget becomes a key factor for success. In this study, we establish a novel and generic multi-objective RNP model by simultaneously optimising two conflicted objectives with satisfying the heterogeneous coverage requirements. Then, we design an improved multi-objective genetic algorithm (IMOGA) integrating a divide-and-conquer greedy heuristic algorithm to solve the model. We further construct a number of computational cases abstracted from an automobile mixed-model assembly line to illustrate how the proposed model and algorithm are applied in a real RNP application. The results show that the proposed IMOGA achieves highly competitive solutions compared with Pareto optimal solutions and the solutions given by four recently developed well-known multi-objective evolutionary and swarm-based optimisers (SPEA2, NSGA-II, MOPSO and MOPS2O) in terms of solution quality and computational robustness.  相似文献   
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