最新刊期
卷 9 ， 期 3 ， 2025
- 摘要：The Internet of things (IoT) has emerged as a significant driving force behind the development of the intelligent era. The technological concepts and evolution of IoT within the context of the industrial revolution were analyzed, its current global status and trends were examined, and strategic development directions and key research priorities for technological innovation in China's IoT sector during this intelligent era were identified. Based on an analysis of the scientific challenges and major issues facing the IoT industry, analytical insights and development strategies for the advancement of IoT technology and industry were proposed.关键词：IoT technological concepts and philosophy;IoT development status and trend;IoT technology and industry development direction;intelligent new infrastructure construction;new-type network infrastructure345|245|0更新时间：2026-01-26
Review
- 摘要：Global navigation satellite systems (GNSS) can provide all-day positioning, navigation, and timing (PNT) services in our daily life. However, the requirement of location is not limited to daily life. In high latitude areas, sparsely populated remote areas, and complex environmental areas, the ground infrastructure of GNSS is incomplete, which greatly affects the positioning accuracy and speed of GNSS. Once an emergency occurs, it is difficult to quickly narrow down the search range of the target, resulting in great losses and dangers. Low earth orbit (LEO) satellites can compensate for the shortcomings of GNSS positioning in the above-mentioned areas in terms of satellite quantity, satellite signal frequency, and satellite positioning principle. Firstly, the principle of LEO satellite positioning was introduced. Then, the research status of LEO satellite positioning technology was summarized and analyzed. Finally, the challenges of LEO satellite positioning technology and future research directions were explored.关键词：LEO satellites positioning;Doppler measurement;satellite positioning and navigation;GNSS172|256|0更新时间：2026-01-26
- 摘要：Unmanned aerial vehicles (UAVs) are widely used in various scenarios. The integrated sensing and communication (ISAC) technology offers new opportunities to meet the huge demands of UAVs for positioning. Orthogonal time frequency space (OTFS), due to its delay-Doppler domain modulation characteristics, can well satisfy the sensing requirements of the ISAC system in high-speed mobile scenarios. However, in millimeter-wave (mmWave)/terahertz frequency band, when OTFS-ISAC based on large antenna arrays meets a high-speed moving UAV, Doppler effect and beam squint effect cannot be ignored. In response to the beam squint effect, an iterative algorithm based on the fast Fourier transform (FFT) was proposed for positioning estimation. Through experimental simulation and analysis, it is proved that this algorithm can effectively approach the Cramér-Rao lower bound (CRLB).关键词：ISAC;UAV;Doppler effect;beam squint;positioning106|101|0更新时间：2026-01-26
- 摘要：Deep reinforcement learning has been widely applied in charging station recommendations in the internet of vehicles, but training separate neural networks for each region are often required by traditional methods, leading to increased computational load and data demands. Transfer learning accelerates the learning process for new tasks by leveraging knowledge from previous tasks, thus reducing redundant training. Therefore, a transfer reinforcement learning-based cross-domain charging station recommendation algorithm was proposed. An embedding encoder was introduced by this algorithm to align the system state and action space dimensions between the source and target domains, effectively solving the dimensionality discrepancy problem. Additionally, variational distributions were constructed based on mutual information to maximize the similarity between pre-aligned and post-aligned target domain states to ensure effective transfer. Compared to three typical charging station recommendation algorithms, in the low-dimensional to high-dimensional transfer, the average total charging time of the proposed algorithm was reduced by 57.6%, 59.3%, and 7.1%. In the high-dimensional to low-dimensional transfer, the reductions were 12.3%, 40.8%, and 4.7%, respectively. Simulation results demonstrate that the proposed algorithm exhibits strong transferability and significantly enhances the performance of cross-domain charging station recommendation systems.关键词：deep reinforcement learning;transfer learning;mutual information;charging station recommendation124|143|0更新时间：2026-01-26
- 摘要：With the application of the Internet of vehicles, the real-time, deterministic, and reliable data transmission for the in-vehicle networks become crucial. In response to the issues of untimely data forwarding, high packet transmission delay, and high complexity of scheduling algorithms in-vehicle time-sensitive networks, a time-aware traffic scheduling algorithm based on maximum matching was proposed. This algorithm transformed the input queuing scheduling problem into a maximum flow matching problem with deadline guarantees and achieved maximum weight matching scheduling on a per-slot basis. In scheduling sets containing tasks with two or more deadlines, idle link and slot resources were fully utilized to pre-push packets with larger deadlines. This effectively improved the throughput of the switching system and reduced the average packet delay. Simulation results demonstrate that compared with traditional scheduling algorithms, the proposed algorithm achieves 5%~15% throughput performance improvement and 15%~46% average packet delay performance improvement.关键词：in-vehicle time-sensitive network;input queuing system;deadline guarantee;maximum matching;traffic scheduling99|121|0更新时间：2026-01-26
- 摘要：The development of Industry 4.0 and smart factories places higher demands on deterministic low latency and low jitter for network transmission. To address the issue of hybrid transmission of event-triggered flows and time-triggered flows in large-scale deterministic network, an in-situ flow earliest deadline first scheduling (IFEDS) based on information telemetry for hybrid time-sensitive flows was proposed. The networking telemetry and packet coloring were achived based on the in-situ flow information telemetry. A deadline-based probabilistic packet coloring algorithm and a coloring-based semi-preemptive earliest deadline first scheduling algorithm were designed. Simulation results based on the OMNeT++ show that the average end-to-end latency of IFEDS under high load is 6.84% lower than Deadline-TSN, and the packet loss rate is reduced by 0.37% compared with Deadline-TSN when the event-triggered flow ratio is 40%.关键词：deterministic network;time-sensitive networking;scheduling;in-situ flow information telemetry;cyclic specified queuing and forwarding72|114|0更新时间：2026-01-26
- 摘要：During the process of offloading tasks from devices to the UAVs, tall buildings can cause issues such as signal attenuation, multipath propagation, and signal blockage, thereby impacting the task offloading rate of devices. To address this challenge, the RIS was introduced to improve channel quality and enhance task offloading rates. It is worth noting that RIS operates without its own energy source and user energy resources are limited. To overcome this energy constraint, UAV employing RF signal-based energy transmission beams to recharge both devices and RIS was proposed. Secondly, an energy-efficient optimization strategy for RIS-enhanced wireless powered MEC network was proposed by jointly optimizing downlink and uplink phase beamforming, UAV trajectories, and task offloading rates. Building upon this foundation, a block coordinate descent (BCD) algorithm that combines semi-definite relaxation (SDR) and successive convex approximation (SCA) techniques was introduced. The extensive simulation results validate the effectiveness of the proposed optimization strategy in achieving a great balance between energy supply and task offloading energy consumption while meeting the task offloading requirements of ground terminals, thus enhancing the overall energy efficiency of the network.关键词：MEC;UAV communication;RIS;energy harvesting207|106|0更新时间：2026-01-26
- 摘要：To tackle the issues of mutual interference among bidders in spectrum sharing systems and the low spectrum utilization resulting from a fixed interference protection range, a two-stage auction scheme that operates under interference constraints was proposed. In the first-stage auction,a winner and price determination optimization problem was formulated to maximize the spectrum utility, which is solved by the proposed greedy-policy spectrum auction algorithm. Followed by the second-stage auction, a joint optimization problem for channel allocation and interference protection range flexible adjustment was formulated, which is solved by the proposed genetic-based auction algorithm. The convergence of the proposed algorithms was verified by extensive experiments. Furthermore, simulation results demonstrate that the proposed scheme can serve more spectrum users compared to traditional spectrum reuse schemes on the same channels, and potentially improve spectrum auction utility and channel reuse rates by approximately 50% in scenarios of scarce spectrum resources.关键词：dynamic spectrum sharing;two-stage auction;interference constraints;graph theory;interference protection zone22|55|0更新时间：2026-01-26
- 摘要：With the widely used of smartphones, traditional explicit authentication methods (e.g., passwords, fingerprints) are increasingly vulnerable due to their reliance on active user input, making the non-invasive implicit authentication a critical research focus. A transfer autoencoder-based implicit authentication framework for smartphones was proposed. Users’ behavioral features were captured during pattern unlocking (e.g., accelerometer and gyroscope data) through multimodal sensors, an autoencoder was employed to extract discriminative latent representations, and a transfer learning mechanism was incorporated for rapid model fine-tuning. The results of the experiment indicate that following the pre-training of the scheme on a 10 GB offline dataset, which is generated from the unlocking patterns of 50 users across 4 smartphones, the online authentication process can be executed in a mere 1.3 seconds, achieving an accuracy rate of 99.06%. This performance is markedly superior to that of traditional machine learning methods, such as support vector machine (SVM), which exhibits an accuracy rate of 89.19%. Furthermore, it surpasses conventional deep learning approaches, including K-nearest neighbor (KNN) with an accuracy of 95.49%, as well as existing state-of-the-art (SOTA) schemes like EspialCog, which achieves an accuracy of 98.76%. Additionally, it is noteworthy that users are required to perform the unlocking behavior only six times prior to utilization in order to complete the model adaptation, thereby balancing considerations of security with user experience.关键词：implicit authentication;autoencoder;transfer learning;pattern unlock;privacy protection52|59|0更新时间：2026-01-26
- 摘要：A near-field antenna for ultra-high frequency radio frequency identification (RFID) reader with a multi-ring structure and uniform magnetic field was designed. The antenna was circular in shape and consisted of 8 fan-shaped radiating patches distributed in rotation. Through coupling between fan-shaped radiating patches and loading parasitic arc-shaped patches, the surface current of the antenna showed the same rotation direction, which could generate a relatively uniform magnetic field and a multi-polarized electric field in the identification area. The antenna had a diameter of 130 mm and was printed on a flame retardant 4 (FR-4) dielectric substrate with a thickness of 1.6 mm. The measured results show that the bandwidth of the reflection coefficient |S11|<-10 dB is 904~932 MHz. A relatively uniform magnetic field can be generated within a circular area with a diameter of 130 mm above the antenna. At a power output of 30 dBm, the farthest reading distance for the 100% identification rate of the magnetic coupled ring tag J41 is 16 cm when the Impinj E710 reader is used for tag testing. The proposed antenna can generate a multi-polarized electric field that exhibits similar readability for tags placed in different directions.关键词：RFID;near field antenna;uniform magnetic field;multi-ring structure26|132|0更新时间：2026-01-26
- 摘要：Firstly, the existing unsourced multiple access coding schemes were introduced in two aspects: linear codes and compressed sensing codes. On this basis, two unsourced multiple access spread spectrum sequence detector schemes proposed by Pradhan and Ahmadi were analyzed and compared. Then, power was redistributed for the compressed sensing coding scheme proposed by Amalladinne in 2020. The simulation results showed that when the number of active users is low, a certain performance improvement is observed.关键词：unsourced multiple access;compressed sensing code;linear code;spread spectrum sequence detector38|147|0更新时间：2026-01-26
- 摘要：Rate adaptation (RA) technology is a key feature in Wi-Fi networks, capable of selecting the optimal data transmission rate based on real-time observed channel conditions. However, most existing rate adaptation algorithms exhibit two issues. Firstly, methods relying on cross-layer information feedback are often challenging to implement in practical applications. Secondly, the strategies employed are over-conservative in rate selection, opting for lower rates when the signal-to-noise ratio (SNR) varies between two selectable modulation levels. A rate adaptation algorithm based on the dueling double deep Q-network (D3QN) in deep reinforcement learning was proposed to address these issues. This algorithm eliminated the need for cross-layer feedback and dynamically adjusted the data rate through the observation of physical layer information. Additionally, it referenced existing table-based rate adjustment methods during the design of the reward function and model loading phase. Simulation results show that the proposed algorithm can rapidly adapt to environmental changes and achieve higher throughput performance compared with four baseline methods across various scenarios.关键词：Wi-Fi networks;deep reinforcement learning;D3QN;adaptive modulation52|72|0更新时间：2026-01-26
- 摘要：In recent years, 3D printing technology has played an increasingly important role in a growing number of industries. However, as a relatively new technology, it tends to exhibit more defects during the printing process compared to traditional manufacturing methods. These defects can significantly impact the performance of the final product. Given that 3D printed parts typically have complex and highly optimized geometric shapes, traditional detection technologies struggle to meet the demands for precision and efficiency. To address this challenge, this paper introduces a 3D printing defect detection algorithm based on an improved version of YOLOv5. The algorithm makes extensive refinements to the YOLOv5 model, achieving model lightweighting by replacing the loss function and introducing an attention mechanism. The newly designed detection system is characterized by a smaller parameter scale, rapid inference speed, high detection accuracy, and strong robustness. Compared to the original YOLOv5s model, the improved lightweight model has achieved a detection accuracy of 94.2%, and has nearly halved the parameter scale. This advancement not only enhances detection efficiency but also provides an effective technical solution for 3D printing defect detection and fault diagnosis.关键词：3D printing;defect detection;deep learning;YOLOv5;attention47|66|0更新时间：2026-01-26
- 摘要：In view of the fire safety requirements of urban rail transit, the technical optimization and domestic application research of fire alarm system was focused. By analyzing the environmental characteristics and equipment status of rail transit, systematic research on the integrated design and domestic substitution of fire alarm equipment was carried out. Based on the particularity of the scene, an innovative integrated design scheme was proposed, and multi-dimensional perception and rapid linkage response of fire signals were achieved through module integration and intelligent algorithm optimization. Meanwhile, the path of large-scale application of domestic equipment was explored and the effectiveness was verified in cost control, technology adaptation and industrial autonomy. The results show that the integrated design significantly improves the system coordination and early warning reliability; the application of domestic equipment not only reduces construction and operation and maintenance cost, but also promotes independent innovation and industrial upgrading in fire protection technology .关键词：fire alarm;rail transit;integrated design;intelligent algorithm;system reliability180|273|0更新时间：2026-01-26
- 摘要：Accurate positioning performance is an important requirement for safe driving of automobiles. While existing global navigation satellite system (GNSS) performs well in open-air scenarios, achieving high-precision positioning in GNSS resistant environments such as tunnels remains a challenge. Especially in the all-metal environment of the steel shell immersed tube tunnel, the satellite signal is extremely unstable, or even completely unable to receive. To address this challenge, a co-localization architecture for enabling roadside unit (CAE-RSU) in tunnels was proposed, which aimed to solve the problem of impenetrability of satellite signals. Seamless, continuous and highly accurate positioning services were enabled. Specifically, the RSUs set up in the tunnel were used to establish the vehicle-to-everything (V2X) positioning system, and the traceless Kalman filter algorithm was used to further improve the reliability and accuracy of positioning. Simulation results show that the proposed positioning algorithm can achieve superior localization performance even under high-speed motion and high-noise environments.关键词：autonomous driving;vehicle localization;satellite denied environment;steel shell immersed tube tunnel132|123|0更新时间：2026-01-26
- 摘要：In order to analyze the factors that affect the driver’s collision avoidance control behavior during the car following, a simplified car following model was set up with model parameters, and a test vehicle was built using radar and video monitoring systems and sensors for testing. Recruiting test personnel to conduct tests, Matlab was used to capture test data, and then filtering algorithms were employed to process the data in order to obtain valid data. Studying the distribution characteristics of individual driving behavior indicators, it was found that THW and TTC showed relatively small changes in the timing of releasing the accelerator pedal and pressing the brake pedal, indicating that THW and TTC were more in line with drivers’ subjective judgment of rear end collision risk. Analyzing the distribution characteristics of THW and TTC parameters in 40 samples of driving behavior, it was found that the distribution characteristics of individual and overall indicators were basically consistent, indicating that different drivers mostly had similar driving behaviors. Correlation analysis is conducted, and the results show that the distance between vehicles is most closely related to the relative speed of the two vehicles. The correlation between the two action moments reached 0.81 and 0.76, respectively, indicating that TTC is more in line with the driver’s judgment of rear end collision risk. The impact of urgency on driving behavior is analyzed, and it is found that the more urgent the deceleration of the vehicle ahead, the shorter the reaction time of the following vehicle driver. Weather conditions can also affect drivers’ judgment of rear end collision risk. In rainy and foggy weather, the following distance significantly increases, indicating that drivers will increase the following distance to cope with rear end collision risk under unfavorable weather conditions. In addition, road conditions can also affect drivers’ following behavior.关键词：car-following model;driving operation behavior;correlation analysis;anti collision decision-making;influencing factor48|117|0更新时间：2026-01-26
- 摘要：Federated learning (FL) allows multiple clients to train a global model collaboratively by sharing only model updates without uploading local data. But due to its distributed global aggregation mode, FL is vulnerable to the malicious impact of label flipping attacks. Therefore, a client selection algorithm was proposed for FL against label flipping attacks. Specifically, the algorithm obtains the reliability score of each client based on the cosine similarity of client model and auxiliary client model and the accuracy of client model, and carries out weighted aggregation according to the reliability score to obtain the global model. By assigning higher weights to benign clients, the influence of malicious clients on the global model can be significantly reduced and the accuracy of the model can be improved. Then, Thompson sampling method was integrated to calculate the probability of each client being selected for aggregation and determine the clients participating in the aggregation in the next round based on the historical benign data of the clients. By screening more benign clients for aggregation, label flipping attacks can be effectively prevented and the robustness of the model was improved. Simulation results show that compared with the existing FedAvg and FLTrust algorithms, the proposed algorithm can defend against label flipping attacks more effectively and achieve higher accuracy.关键词：federated learning;label flipping attack;Thompson sampling;client selection60|29|0更新时间：2026-01-26
- 摘要：The internet of things (IoT) is a key trend in smart tourism, involving multiple stakeholders like government management, public cloud platforms, device manufacturers, scenic areas, and tourists. IoT devices, often deployed in public spaces, are vulnerable to physical attacks, making identity authentication critical for security. A certificate-free identity authentication method based on administrative applications was proposed, using MQTT protocol message queues to maintain device security status, addressing issues with low-power devices in sleep mode. Based on national cryptographic algorithms, secure and controllable IoT information was ensured. Performance evaluations show that it effectively helps prevent security threats, achieving an average authentication accuracy of 99.7%, with embedded RAM and FLASH usage not exceeding 35 KB and 30 KB, suitable for smart tourism applications.关键词：smart tourism;IoT;identity authentication;MQTT;Chinese cryptographic algorithm53|75|0更新时间：2026-01-26
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