Advanced high-voltage power electronics demand low-cost isolated current sensors with wide bandwidth and high accuracy that support increasing switching frequencies. However, existing high-performance solutions rely on costly architectures. To address this, this work presents a low-cost yet high-performance Hall-based current sensor. By employing non-spun voltage-biased Hall plates as well as an inverter-based input stage, the proposed design provides a more than 3× improvement in resolution versus other wideband Hall sensors, achieving a 42 µTrms resolution over a 5 MHz bandwidth. A SAR-accumulator offset calibration scheme cancels the large offset of non-spun Hall plates, reducing it to only 30.5 µT at room temperature. Temperature-dependent resistor compensation limits Hall sensitivity drift from 49% to 2% across 0 °C–125 °C. This design achieves a 150 dB FoM that represents a 3 dB improvement compared to prior art, enabling high-precision wideband current sensing at low cost.

Barcodes are a key IoT technology for product identification and supply chain traceability, yet they are limited in data capacity and security. To address these limitations, we propose a barcode steganography framework based on image embedding and deep learning. Experiments demonstrate robust information hiding, reliable retrieval and multi-target recognition under real-world conditions. Applied to both 1D and 2D barcodes, the method generates image-augmented codes with significantly enhanced capacity, security and practicality.

Verifiable and privacy-preserving SQL execution is important for hybrid on-chain/off-chain data architectures, where raw data is stored off-chain for scalability while data integrity is anchored on-chain. Existing solutions either incur high proof and communication costs or do not fit the requirements of blockchainside verification. This paper presents ZkChainDB, a templatebased verifiable SQL engine for off-chain databases using zkSNARKs and blockchain.ZkChainDB follows an “off-chain execution, on-chain verification” model. An off-chain service provider executes approved SQL query templates over private data and generates succinct zero-knowledge proofs, while the blockchain verifies the proof against the committed dataset state without accessing raw records. We design a query-plan driven SQL-to-circuit framework that compiles a practical subset of SQL operators, including selection, projection, sorting, Top-K, and group-by aggregation, into modular arithmetic circuits. We further introduce semanticsaware optimizations based on Random Linear Combination (RLC), Grand-Product (GP) checks, and pseudo-index structures, which verify result consistency without fully replaying database execution inside the circuit.Experimental results show that ZkChainDB proves queries on 1,000 and 10,000 rows in 16.67 s and 124.67 s, respectively, while maintaining millisecond-level on chain verification and an approximately 1 KB proof size. Compared with prior systems such as ZKSQL and PoneglyphDB, our design is better aligned with blockchain-side verification requirements in terms of proof compactness, low verification latency, and non-interactive verification.

This paper presents a fully dynamic incremental noise-shaping SAR ADC with a continuous-time (CT) front-end and a discrete-time (DT) back-end. The CT input stage continuously tracks the input signal, eliminating kT/C noise associated with sampling and enabling reduced input capacitance, thereby lowering the power consumption of the input driver and reference buffer. A dual-role floating inverter amplifier (FIA) is used as both preamplifier and residue amplifier to constrain residue swing and suppress offset-induced overrange at the CT–DT interface. In the DT back-end, a residue-reuse-based incremental noise-shaping scheme reduces the activation frequency and power consumption of the residue amplifier. The ADC is designed in a 55-nm CMOS process with a 1.2 V supply and occupies an active area of 0.084mm2. Post-layout simulation results show an SNDR of 91.2 dB over a 200-kHz bandwidth while consuming 172 μW, achieving a Schreier FoM of 181.9 dB.

This paper presents a low-power, high–dynamic-range Photoplethysmography (PPG) readout front end based on a dual-stage ZOOM2 light-to-digital converter (LDC). The proposed architecture performs two sequential successive-approximation-register (SAR) assisted coarse quantization steps within a single LED activation cycle. The first SAR stage (8-bit) cancels the dominant DC component, while the second SAR stage (5-bit), combined with a second-order sigma–delta (ΣΔ) modulator, digitizes the residual AC signal. Behavioral-level simulations show that the design achieves a signal-to-quantization-noise ratio (SQNR) of approximately 107.4 dB within a 20 Hz bandwidth, while the single-cycle conversion time is shortened to 39.8 µs including decimation, which is only approximately one-third that of conventional incremental sigma–delta modulator (ISDM)-based LDCs without digital filtering.

This article presents an offset cancellation technique for single-ended hybrid continuous-time/discrete-time (CT/DT) Sigma Delta current-to-digital converters (CDCs). By introducing an auxiliary amplifier in the main amplifier's output branch, the proposed method suppresses structural offset caused by integration node clamping. Simulation results show a similar to 20 dB reduction in DC offset and improved robustness against process variations. With the proposed amplifier integrated, system-level simulation achieves a Figure of Merit (FoM) of 177.6 dB, highlighting a strong trade-off between power, speed, and resolution.

The collection and application of health care data are crucial for advancing research and improving healthcare. However, privacy and security concerns, particularly with sensitive data, pose significant challenges. Traditional identity-based verification systems, which rely on centralized servers, struggle in medical contexts due to regional data management complexities and the vulnerabilities of centralized models. In this paper, we propose MedZKChain, a privacy-preserving health care device verification system designed to address these challenges. By combining blockchain technology with zero-knowledge proofs, MedZKChain enables decentralized device attribute verification while ensuring data integrity and privacy. The system provides a solution for managing the access of medical records in different regions. MedZKChain leverages decentralized storage to reduce blockchain burden and uses zero-knowledge proofs to allow for secure verification and access authorization without revealing sensitive data. Experimental results demonstrate that, when authorized querying 1,500 patient data records, the proof size in MedZKChain remains less than 100 KB, the proving time is less than 3 seconds, and the verification time is below 0.8 seconds. These results highlight the system efficiency, scalability, and its effectiveness in enabling decentralized, verifiable.

This article presents an area- and power-efficient current-to-digital converter (CDC) system for bioelectric current sensor applications. To address the requirements of high resolution, compact size, and low power in such systems, a hybrid continuous-time/discrete-time (CT/DT) incremental sigma-delta modulator (SDM) architecture is proposed. Compared to conventional CT-based CDCs, the hybrid approach offers advantages in area and efficiency, which are systematically analyzed and validated through chip implementation. The proposed system employs a resistor-free continuous-time (CT) integrator as its first stage and a switched-capacitor (SC) integrator as the second stage. The integration of a recycling folded-cascode (RFC) operational amplifier further optimizes power consumption. In addition, the implemented D flip-flop (DFF)-assisted feedback loop and enhanced charge injection cancellation switch improve the system's harmonic and noise characteristics. The chip is implemented using a standard 0.18- mu m process, the feedback resistor and integration capacitor can be adjusted through on-chip digital registers to accommodate different sensor current output ranges. The proposed CDC achieves 94.9-dB signal-to-noise and distortion ratio (SNDR) with 55-mu A current consumption and core area of 0.17 mm(2). The figure of merit (FoM) for the system is 164.9 dB, achieving a good balance between resolution and power consumption.

A 24-bit sensor Read-out Integrated Circuit (ROIC) with a +/- 5V input range is presented in this paper. The system utilizes a two-opamp programmable gain amplifier (PGA) and a third-order incremental switched-capacitor sigma-delta (SC Sigma Delta) analog-to-digital converter (ADC) to achieve a front-end gain ranging from 1 to 128. The PGA comprises a gain-boosting amplification stage and a class-AB output stage, effectively eliminating offset and 1/f noise through chopping. The ADC adapts a configurable zero optimization loop, allowing enhanced noise transfer function (NTF) at different output data rates (ODRs). Double-sampling technique is used to further improve the Signal-to-Noise Ratio (SNR). This system is realized in 0.18 mu m standard CMOS process, providing three power modes and supporting up to four input signal channels. It exhibits a temperature coefficient of less than 2 ppm/degrees C over the operating range of -40 degrees C to 105 degrees C, while achieving a maximum Effective Resolution (ER) of 23.8 bits at a ODR of 10 samples per second (SPS). The calculated Figure of Merit (FoM) for the proposed ROIC reaches 173.7 dB.

Blockchain-based supply chain traceability systems are characterized by decentralization, transparency, and immutability. However, if all nodes replicate the entire ledger, it would result in significant storage overhead. Some nodes might be forced to exit the system due to inadequate storage resources. Additionally, the chained structure of blockchain implies that query delays will significantly increase as the volume of data grows. Furthermore, the immutable nature of blockchain demands a higher level of accuracy in the original data within the traceability system, as once erroneous data is uploaded to the blockchain, it cannot be altered or removed. In this paper, First, we analyze the requirements of supply chain business scenarios and the characteristics of traceability data. Then, we propose a semantic multi-chain storage architecture, categorizing data from different business entities into respective semantic side-chains, thereby addressing issues such as insufficient node storage and on-chain data explosion. Second, We introduce a semantic aggregation storage optimization technique, consolidating data with identical semantic keys into a single block, thereby reducing the number of blocks accessed during queries and improving query efficiency. Lastly, for the first time, we introduce a pre-onchain data reliability verification mechanism based on data characteristics. The results indicate that the proposed solution can offer reduced on-chain storage space, faster query speeds, and enhanced reliability of the original data sources.

This paper presents a high area and power efficiency incremental hybrid Continuous-Time/Discrete-Time Sigma-Delta Modulator (CT/DT SDM) based Current-to-Digital Converter (CDC). The system utilizes a resistor-free continuous-time integrator as the first stage and a Switched-Capacitor (SC) integrator as the second stage to achieve second order noise shaping, leading to significant reduction in the overall area and power consumption when current signal is served as sensor output. The integration of a recycling folded-cascode (RFC) op-amp further contributes to power reduction, while the enhanced charge injection cancellation switch further improve the harmonic and noise characteristics of the system. The proposed CDC achieves 102.5dB Signal-to-Noise and Distortion Ratio (SNDR) with total current consumption of only 54.8 mu A and an area of 0.08 mm(2). The calculated Figure of Merit (FoM) for the system is 172.5dB, indicating an outstanding trade-off between system resolution and power consumption.

With the spread of distributed renewable energy, residents are shifting from being mere consumers to being energy producers and consumers. This role shift poses challenges to the electricity trading mechanism that connects distributed renewable energy sources to the grid. In this paper, a new efficient and secure blockchain-based distributed community energy trading mechanism is proposed, called CE-SDT. Our system is proved to be stable and scalable. It can also help shift loads and power peaks and reduce customer costs by 60%. As a result, our proposed blockchain-based trading mechanism, as compared to the centralized trading mechanism, is applied to microgrids formed by distributed renewable energy sources, not only obtaining greater economic benefits but also reducing the carbon footprint of residents, and furthermore, it promotes low or zero-carbon configurations of the power system, thereby achieving certain environmental benefits.

Blockchain-based traceability systems are a promising approach because they are decentralized, transparent, and tamper proof; however, if all traceability data are uploaded to a blockchain platform, it may affect the efficiency or even lead to data explosion. Additionally, it is difficult to guarantee the reliability of the original data source of massive Internet of Things (IoT) devices. Furthermore, when different enterprise nodes adopt different data storage structures, the costs that are associated with data sharing will increase. In this paper, we have proposed a trustworthy product traceability system that is based on hyperledger fabric and Electronic Product Code Information Service (EPCIS), which is not only capable of making products traceable, but it can also authenticate and authorize the IoT devices that are used for data collection. First, we adopted the on-chain and off-chain collaborative management mechanism in order to alleviate data explosion on the chain. Second, we proposed a scheme to authenticate and authorize devices based on blockchain. Third, we complied with EPCIS and Core Business Vocabulary (CBV) standards and provided the EPCIS location discovery service in order to improve the interactivity. Finally, we implemented and tested the proposed traceability system and compared it with the existing research. The proposed solution provides product information traceability, data tamper proofing, data confidentiality, and data source reliability.

Digital watermarking based on the scalable part of H.264 in MPEG-4-Scalable Video Code (SVC) is a promising technology in the field of video watermarking. However, the existing watermarking algorithms for H.264/SVC framework are difficult to satisfy the requirement of copyright protection. In this work, we extend the existed framework for invisible watermarking adopting the Discrete Cosine Transform (DCT) with a scalable watermarking algorithm, in order to adapt the multi-resolution property of the H.264/SVC. The original watermark is re-constructed to different scales by the pyramid decomposition, and the re-constructed watermarks are embedded in the DCT sub-blocks by modulating their positive and negative coefficients. Additionally, the sub-blocks are adaptively selected from the macro-blocks by a designed key control mechanism. According to the test results, the embedded watermarks are invisible and robust. The proposed method has achieved the Peak Signal to Noise Ratio (PSNR) in a value no worse than 41 dB and the Normalized Correlation (NC) in a value greater than 0.85. The proposed algorithm has can resist the attacks with different quantization steps.

Using steganography for data hiding is becoming a main subject to ensure both information security and picture quality. Traditional steganography algorithms usually convert secret information into a binary string and embed it in the pixel data of the cover image. In order to ensure the information security as well as convenient transmission, this work studies the steganography algorithm of embedding the QR code containing secret information into the cover image, based on the JSteg algorithm. Secret messages with different sizes have been tested by many cover images and standard parameters have adopted to verify the efficiency. According to the experimental results, all the PSNR in a value that is greater than 47.6 dB. The proposed method has high security and more imperceptibility.

In recent years, food safety issues have drawn growing concerns from society. In order to efficiently detect and prevent food safety problems and trace the accountability, building a reliable traceability system is indispensable. It is especially essential to accurately record, share, and trace the specific data within the whole food supply chain, including the process of production, processing, warehousing, transportation, and retail. The traditional traceability systems have issues, such as data invisibility, tampering, and sensitive information disclosure. The blockchain is a promising technology for the food safety traceability system because of the characteristics, such as the irreversible time vector, smart contract, and consensus algorithm. This paper proposes a food safety traceability system based on the blockchain and the EPC Information Services and develops a prototype system. The management architecture of on-chain & off-chain data is proposed as well, through which the traceability system can alleviate the data explosion issue of the blockchain for the Internet of Things. Furthermore, the enterprise-level smart contract is designed to prevent data tampering and sensitive information disclosure during information interaction among participants. The prototype system was implemented based on the Ethereum. According to the test results, the average time of information query response is around 2 ms, while the amount of on-chain data and query counts are 1 GB and 1000 times/s, respectively.

随着医疗电子产业的不断发展,植入式电子产品得到广泛应用,为解决传统结构中因电池体积过大、续航能力不足等造成的限制,摒弃电池的无线能量传输模块成为一个热门的研究方向.为防止通过无线传输方式获取的能量信号中的交流纹波对后续的微小信号处理产生干扰,设计了一种高电源抑制比的低压差线性稳压器,通过加入纹波消除支路,达到提高高频段电源抑制比的目的.在0.13μm CMOS工艺下进行流片验证,测试结果表明:当负载电流为1 mA时,在100 kHz到20 MHz频率范围内,电源抑制比稳定在-60 dB.

This paper presents a temperature sensor with glucose sensor interface based on configurable incremental sigma delta (Sigma Delta) Analog-Digital-Converter (ADC). A current readout circuit is implemented based on the same Sigma Delta modulator of the temperature sensor. New dynamic biasing scheme of inverter-based operational transconductance amplifier (OTA) is proposed to improve the settling time of the biasing voltages. This design was fabricated using 0.13 mu m CMOS process. Compared with the traditional circuit, this circuit reduced the chip area by 25%. According to the test results, when the temperature changes from 20 degrees C to 50 degrees C, the temperature sensor inaccuracy is +/- 0.15 degrees C and the ADC achieves 9.3 effective number of bits (ENOB) with 3 mu W power consumption.

Food safety has drawn worldwide attention because of its enormous impact on human health and social stability. Although traceability systems based on Internet of Things (IoT) can improve the visibility of the food supply chain, the trust service is necessary to ensure the data origin and data integrity. This paper proposes a food traceability system supported by a trust service based on Domain Name System Security Extensions(DNSSEC). A DNSSEC-enabled traceability system is implemented for food safety in China. In the traceability system, the master data and event data of the products is stored in distributed databases owned and managed by the enterprises respectively in the supply chain. Enterprise oriented Internet of Things Information Service (iotIS) is an important component of the distributed traceability system. A trust service for the Internet of Things, iotTS, is proposed to guarantee the data integrity. With this service, it can be ensured that the information stored in the enterprise database is original and has never been manipulated. Lightweight public keys are distributed based on the DNSSEC in this solution. Compared with the existing solutions, the proposed solution has better scalability and credibility.

An active tag using carrier recovery circuit (CRC) is proposed in this paper. The active tag is compliant with electronic product code class-1 generation-2 (EPC Gen2) passive ultrahigh frequency (UHF) radio frequency identification (RFID) protocol, and it is used to extend the read range of EPC Gen2 RFID systems without changing existing readers. The EPC Gen2 compliant active tag is not reported yet, since it is difficult to generate a synchronized carrier with the reader in the active tag. Hence, the requirements of tag carrier are analyzed in detail, and a suitable CRC is proposed to track and hold the reader frequency in the active tag. An active tag prototype is designed to prove the proposed concept, and the communication between the prototype and a commercial EPC Gen2 reader is verified. The sensitivity of the tag prototype is -39.5 dBm and the output power is -4.5 dBm. That results in a 154.6 m read range under 36 dBm effective isotropic radiated power (EIRP) reader output power and -80 dBm reader sensitivity.