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关键词： Powder metals  

摘要： Laser powder bed fusion (PBF-LB/M) is an additive manufacturing (AM) process to produce high-strength, functionally integrated, lightweight metal components which cannot be built conventionally. This article addresses the expansion of functionality by integrating sensors within closed cavities. For this reason, the building process was stopped just before the cavities were closed. After positioning the sensors, the building process was continued and a solid connection to the AM component was established. © 2024 Wiley-VCH GmbH.

关键词： radio-frequency identification (RFID)   near-field   ultra-high frequency (UHF)  

摘要： Tiny radio-frequency identification (RFID) tags with a 1 mm square scale can be attached to small insects such as ants and used to detect their passage at RFID reader antennas in a laboratory arena. Although the movement paths of ants can be restricted inside a narrow tube, the ants pass through the tube in various postures. A single small coil antenna attached to the tube generates nulls, where the tags become unreadable due to specific tag orientations. This letter proposes a tag reading system with three antennas generating major magnetic field vectors in three orthogonal directions, to eliminate nulls within the tube, regardless of the tag orientation.

关键词： RFID技术   实验室   电脑   运维管理  

摘要： 常规的实验室电脑运维管理系统以运维响应时间优化为主，并未对电脑运维管理参数进行优化，影响系统运行性能。因此，该研究基于RFID技术的实验室电脑运维管理系统设计与应用这一课题。硬件方面，设计RFID阅读器与TP-LINK交换机。软件方面，部署实验室电脑运维管理环境，选择稳定、安全的操作系统作为服务器和工作站的底层平台，确保运维数据的可靠性。基于RFID技术优化电脑运维管理参数，通过无线射频信号实现非接触式的自动识别和数据交换，完成阅读器与电子标签之间的信息传递任务，从而实现管理参数的优化。采用系统测试，验证了该系统的运行性能更佳，能够应用于实际生活中。

关键词： ASK demodulator   current mode   low power consumption   modulation index  

摘要： An ultra-low power fully integrated CMOS current-mode amplitude shift keying (ASK) demodulator for radio frequency identification (RFID) transponders is presented. The proposed ASK demodulator performs signal shaping and amplification in the current domain to achieve higher power efficiency. Owing to a DC elimination technique, the employed current amplifier only amplifies the AC content of the envelope signal resulting in a significant reduction of power consumption. A feedforward correction method is also introduced to match the baseline of the amplified envelope signal with the threshold level of the output buffer, preserving the uniformity of data symbols. The proposed ASK demodulator is implemented in a standard 0.18 mu m CMOS process consuming about 5.4 mu W. A modulation index of 4% and a data rate of 800 Kbps is supported by the proposed demodulator which fully complies with international standards for passive RF communication.

关键词： Fingerprint recognition   Radio frequency   Impedance   Antennas   Security   RFID tags   Entropy   Integrated circuits   Feature extraction   Authentication   RFID   security   authentication   electromagnetic fingerprinting  

摘要： Fingerprinting stands as an effective non-intrusive and non-destructive method to ensure physical security in wireless systems and Radio-Frequency Identification (RFID) applications. Conventionally, the most common state of the art approach involves extracting signal features from the devices and employing machine learning techniques for the classification of counterfeit or cloned ones. This paper explores how to enhance RFID antenna electromagnetic fingerprints by proposing a multi-power interrogation approach. Unlike traditional methods, our technique emphasizes the non-linear behavior of RFID integrated circuits (ICs) by properly varying the reader input power and frequencies. This strategy increases the unpredictability of the IC impedance modulation, thereby extracting richer and more complex information from the RFID tags. Using Shannon Information Theory, we can quantify the entropy of these enhanced fingerprints, revealing an average increase of almost 2 bits in the information content compared to single-power level interrogations. Our findings can lay the foundations to implement more robust RF physical unclonable functions (PUFs) with robust physical keys against counterfeiting and replication threats.

关键词： Radio frequency identification (RFID)  

摘要： Data exchange between electronic tags and the reader-writer in RFID systems is based on the wireless channel. Due to the inherent openness of the wireless channel, the transmitted data information is easy to be eavesdropped by other illegal users. In order to ensure data security, an ultra-lightweight mutual authentication protocol is proposed to solve this problem. In this paper, we independently design a new encryption algorithm, namely the product module synthesis operation. This algorithm is implemented based on bit operations, which can greatly reduce the total computation burden. Using the inherent Hamming weight and anti-Hamming weight information of encrypted parameters, different synthesis operations are carried out based on their product size relationship. Through the protocol analysis, it is shown that the proposed protocol has high security performance and meets the current computational requirements of low-cost RFID systems. © (2025), (Femto Technique Co., Ltd.). All rights reserved.

关键词： Radiofrequency identification   Electromagnetic waveguides   Electric fields   Attenuation   Antennas   Substrates   Frequency measurement   Propagation losses   Surface waves   Rectangular waveguides   Substrate integrated waveguide (SIW)   electromagnetic field confinement device   radio frequency identification (RFID)   near-field RFID reader  

摘要： In this paper, a slotted waveguide structure based on SIW technology is presented as a near-field RFID reader antenna. The structure enables the control of electromagnetic field decay with distance. A prototype that operates within the EPC Gen2 protocol was implemented. The imposed decay factor was achieved as 1 dB/cm at 867 MHz and 2 dB/cm at 915 MHz. The structure was fabricated using a Rogers RO3010 substrate, with silver ink applied to the edges of the SIW. A comparison between theoretical predictions and experimental electric field decay in the broadside direction is presented, demonstrating a high degree of agreement between them. Additionally, S-parameters are provided, illustrating excellent impedance matching across the entire bandwidth. The system's functionality was verified by connecting the device to a Motorola FX7500 RFID reader and testing the read range with a commercial tag oriented and placed in various positions along the structure.

摘要： 充分发挥数据集中和网络互联的优势，从资产基础数据提取入手，实现数据、信息在不同系统之间处理模式的转化，达到“数据共享，业务互关”，确保资产核算和信息准确无误。人民银行分支机构固定资产是机构履职的重要保障，其相关费用支出也是行政事业类预算绩效的关注点，本文在对RFID固定资产管理系统与人民银行分支机构现用的固定资产管理系统功能方面进行对比分析的基础上，以电子设备类固定资产为例提出相关的建议，对推动固定资产从静态管理到动态管理实施，提高预算绩效管理水平有着一定的借鉴作用。

关键词： Operational amplifiers  

摘要： RFID has great potential for applications in integrated bio-consumer electronics such as implantable medical sensors and wearable medical devices as a bridge between bio-signal acquisition and data storage. EEPROM, an important tool for storing biometric information, has been neglected in research in related fields. This paper presents a 3 Kbits EEPROM that could be utilized for passive RFID tag ICs, developed in SMIC 0.13μm EEPROM 2P6M CMOS process, boasting a chip area of 338.28 μm × 310.78 μm. The average power consumption for read and write operations was 560 nA and 31 μA respectively, which is 62% and 6.5% lower than the current state-of-the-art literature. This paper proposes a novel reading circuit that reads data using only one simple inverter, greatly saving power consumption and area compared with the traditional readout method using operational amplifiers. Furthermore, this paper proposes a power-optimized charge pump that switches the frequency divider generated by the low-frequency clock when the voltage rises to a high voltage to reduce power consumption. To fulfill the low-cost advantage, this paper places the device under the MIM capacitor using the MIM (shd) and M4 layers to separate. Thus, it is more suitable for bio-consumer electronics from a commercial perspective. © 1975-2011 IEEE.