Abstract：Aiming at the requirement of current detection for operational amplifier performance, a new low offset operational amplifier circuit is proposed. The closed-loop current sampling circuit is composed of low-loss op-amp, PMOS tube and resistor. The whole op-discharge route is composed of main op-amp and auxiliary op-amp. The high frequency path composed of main op-amp controls the circuit bandwidth, the auxiliary amplifier low-frequency path uses chopper technology and self-zeroing technology to reduce the circuit offset. The circuit was simulated based on the 180BCD process. The simulation results show that the temperature is 27 ℃, the input offset voltage is stable at 9 μV, the operation amplifier gain is 95.50 dB, the gain bandwidth product is 28.2 MHz, the phase margin is more than 76.6°, the CMRR value is 148 dB, and the PSRR value is more than 116 dB. The circuit can be used for high measurement current detection.

Abstract：This article presents the design and implementation of a negative-voltage low-dropout linear regulator (LDO) with bidirectional enable functionality. Firstly, the fundamental architecture and operational characteristics of the conventional negative-voltage LDO are introduced. Based on the application scenarios of the negative-voltage LDO, the necessity for bidirectional enable is put forward. Subsequently, the traditional enable circuit and the proposed bidirectional enable circuit are demonstrated, and analyses are conducted for both positive-voltage startup and negative-voltage startup scenarios. Finally, the negative-voltage LDO chip is designed and fabricated in a 350 nm CMOS process. The test results indicate that the negative-voltage LDO can achieve bidirectional startup within the enable signal range of greater than 0.96 V and less than 5 V, as well as greater than -5 V and less than -0.9 V. Moreover, the enable circuit consumes a current of 873 nA during the positive-voltage startup process and a current of 219 nA during the negative-voltage startup process.

Abstract：An all-GaN power chip is designed to meet the application requirements of high-frequency power modules. The chip integrates the driver circuit and 300 V power devices, which effectively reduces the parasitic inductance caused by the discrete package, and the integrated design can improve the chip's noise immunity and reliability. The chip is prepared in GaN-on-Si process platform and adopts E/D mode IC design. The driver circuit of the chip has an output signal rise time of 4.3 ns and a fall time of 3.4 ns at a switching frequency of 2 MHz, and the power devices are able to work stably at 300 V.

Abstract：This paper introduces the detection methods for data integrity protection mechanism of integrated circuit (IC) card. An improved power-off-testing theory is proposed aiming at the limitations and shortcomings of traditional single-command power-off detection methods, to detect and verify IC card transaction protection mechanism during data recovery process. Using time statistics and power consumption statistics, the effective time zone for power-off testing is calculated to improve testing efficiency. Finally, the effectiveness of the fast detection method for data integrity protection mechanism is verified by experimental results.

Abstract：For the coverage testing of Flash FPGA drivers based on chiplets, the system control registers and boundary scan register modules of Flash FPGA were utilized to configure different driving modes of the FPGA, which were then compared and validated against the traditional configuration of single-chip Flash units. The experimental results show that the driving performance configured by the control registers of Flash FPGA based on chiplets is consistent with that of the traditional single-chip Flash unit configuration, with the testing time reduced by three times.

Abstract：In small and medium-sized permanent magnet synchronous wind turbines, the bridge rectifier + DC / DC converter topology has the advantages of simple structure. The DC / DC circuit has Boost and Buck topologies. Exploring the difference between the maximum power point tracking ( MPPT ) control performance of the two is the key to its optimal design. The measurement and control system is an important means of performance analysis. Through the overall scheme design of the system, the system parameters and indexes are confirmed. The four-leg DC / DC topology is analyzed, and the acquisition of system voltage, current, power and frequency is realized based on high-end current sampling and isolated sampling technology. The power drive and single chip microcomputer control circuit are designed. The software of MPPT climbing search method suitable for single chip microcomputer is discussed. The software design and implementation of the upper computer control system based on LabVIEW is given. The measurement and control system is built, and the MPPT and two topology measurement and control results are compared. The experimental results show that the measurement and control system has achieved the design goal.

Abstract：In industrial production, wired communication methods are usually affected by wiring and transmission distance, which brings a lot of inconvenience to measurement and control tasks, especially in some environments such as high and low temperatures, high noise, and high voltage, where it is not suitable for personnel to participate. Meanwhile, continuous intervention by personnel may lead to potential safety hazards. To solve the above problems and combined with the characteristics of this system itself, a design scheme for a wireless intelligent measurement and control system of an adjustable voltage DC-DC power supply based on "5G module + STM32 + PC" is proposed. The measurement and control functions for remote devices are achieved through the intelligent measurement and control software on the upper computer at the user end. This system has functions such as power supply voltage measurement and control, intelligent error compensation, and 5G wireless communication. The whole system features high control accuracy and high reliability.

Abstract：Nitrogen oxides and particulate matter are the two main pollutants emitted by diesel locomotive exhaust. It is an effective measure to control urban air pollution to monitor the exhaust emission of diesel locomotives by using the vehicle exhaust gas detection device. For a nitrogen oxide gas sensor, based on its detection principle, temperature and humidity will have a greater impact on the chemical reaction in the detection process, so a corresponding temperature and humidity compensation method is required to improve the measurement accuracy of the sensor. In this paper, a vehicle-mounted vehicle exhaust gas detection device is designed and a sensor temperature and humidity compensation method based on Support Vector Regression (SVR), Sine Cosine Algorithm(SCA) and Particle Swarm Optimization (PSO) is proposed. The concentration of nitrogen oxide gas and particulate matter, and the compensation model is used to compensate the temperature and humidity of the sensor detection value. After testing data training and validation, the compensation model can effectively reduce errors caused by temperature and humidity, and can meet engineering requirements.

Abstract：In high-dynamic wireless networks, typically represented by Wireless Body Area Networks (WBANs), recording the state of wireless channels with high temporal precision is a critical preliminary issue for conducting research on transmission optimization schemes. With low cost and portability as core objectives, this paper comprehensively compares several typical wireless development components and selects ESP32+ESP-NOW as the hardware and software development platform. It also designs a set of high-precision wireless channel state collection and recording systems. After design optimization, this hardware and software system can achieve a maximum transmission interval of approximately 257 microseconds. Additionally, through multiple sets of experimental tests controlling variables, the effects of protocol mode, transmission rate, number of cores, thread count, CPU frequency, serial communication, and file read/write on packet transmission intervals and stability were evaluated in detail. The research findings of this paper provide design schemes and test data references for related research in the field of high-dynamic wireless networks.

Abstract：Aiming at the interconnection demand between computing units in embedded heterogeneous computing systems, a message middleware working in publish-subscribe mode is designed for CPU and FPGA platforms. Firstly, we study the publish-subscribe model and the corresponding message transmission method and choose RapidIO as the middleware transmission protocol to solve reliable multicast error control and congestion control problems. Secondly, we study the middleware's communication scheme and the publish-subscribe mechanism's implementation scheme and design the hot-plugging mechanism and the anomaly monitoring module to improve reliability. System validation and testing results show that the middleware has better communication performance, and the hot-plugging mechanism effectively enhances the system's reliability, which has certain advantages compared with other design solutions.

Abstract：In the process of collecting photoplethysmographic (PPG) signals, it is particularly susceptible to noise from the environment and the object being collected, which can cause a large gap between the collected signal and the true value. In response to this problem, a method for denoising PPG signals is proposed in this paper. The paper presents a long-nosed otter optimization algorithm that uses the minimum envelope entropy as a criterion to determine the optimal number of modal components and the punishment factor for the variational mode decomposition (VMD). These two parameters directly affect the quality of the VMD processing results. The original signal is decomposed using VMD, the IMFs are distinguished using cosine similarity, and then the signal is denoised using wavelet thresholding. Finally, the signal is reconstructed to obtain the denoised signal. The simulation and experimental results show that compared with traditional denoising methods, the method proposed in this paper has higher signal-to-noise ratio, lower mean square deviation, and higher waveform similarity.

Abstract：In industry, electric power, transportation and other fields, anomalies are often the precursors of problems or failures in the system. Through anomaly identification techniques, system abnormal behavior can be detected in time to prevent or quickly respond to potential failures and improve system reliability and stability. Current anomaly identification algorithms usually need to introduce expert information (e.g., suitable parameter values), but in many identification scenarios, the data distribution as well as the cause of anomaly occurrence are unknown, resulting in unreliable expert information. Therefore, it is significant to design an anomaly identification algorithm that does not require the intervention of expert information. In this paper, an adaptive anomaly identification algorithm is designed. Specifically, it identifies numerous small clusters by K-means, and then counts the distribution probability of the number of objects in each cluster to generate a probability distribution graph. From the probability distribution graph, it can be clearly observed which clusters contain significantly smaller numbers of objects than other clusters, and thus they are recognized as anomalous clusters in which the objects are recognized as anomalies. In other words, the probability distribution graph replaces expert information and assists the user in identifying valid anomalies when the distribution as well as the cause is unknown.

Abstract：Wi-Fi sensing based indoor intrusion detection system is a system that can detect mobile entities without attaching any device to them. To address the potential effects caused by the complex amplitude and phase variations of current detection methods, this paper proposes a new method for indoor intrusion detection (LSID: Long Short-Term Memory and Support Vector Machine Intrusion Detection) that fuses long short-term memory networks and support vector machines.The LSID method adopts a new eigenvalue modeling approach, which utilizes a long short-term memory network that can learn the temporal features and can capture the long-term dependencies of temporal signals, the difference between the true value of the channel state information and the predicted value of the long short-term memory neural network is used as the eigenvalue, which can more accurately capture the intruder's influence on the signal state information. The detection method is validated in the school laboratory environment after many experiments, and the final detection accuracy reaches 99.21%. Through the comparison of multiple groups of experiments, the results show that the LSID method has the effectiveness and feasibility, and the accuracy is significantly improved compared with other intrusion detection methods.

Abstract：With the continuous advancement of antenna technology, the importance of near-field measurement techniques is also increasing. In near-field measurements, probe malfunctions or overly large sampling intervals can lead to significant errors in the extrapolated far-field pattern. To address this issue, a method for reducing near-field measurement errors based on Kriging interpolation is proposed. The study firstly simulates a rectangular aperture horn antenna using HFSS, then compares near-field data sampled at 1° intervals with data sampled at 6° intervals. Based on the 6° sampling data, 30% of the sampling points are randomly reduced, and missing data are filled using the Kriging interpolation method. The near-field to far-field transformation is then performed and compared with the simulated far-field results. The results indicate that, compared to the errors before interpolation, the error in the E-plane is reduced by 1.65 dB, and the error in the H-plane is reduced by 4.93 dB, while the number of sampling points is reduced by 30%. These findings demonstrate that the near-field data correction method based on Kriging interpolation can effectively reduce measurement errors, even maintaining high accuracy in the event of probe malfunctions.

Abstract：This paper introduces an engineering realization of a Ka-band miniaturized airtight wideband power amplifier. Using 16 GaN power chips and 1 GaAs driver chip, the power is synthesized by combining a microstrip ring power divider/combiner with waveguide power divider/combiner and synthesizer network. The continuous wave saturated output power at 25~31 GHz is greater than 140 W. The power amplifier uses a forced air cooling solution with a finned heat sink, which improves the heat sink’s heat dissipation efficiency and provides good heat dissipation performance. The technical condition of the power amplifier is stable, its reliability and practicality meet the requirements for engineering use, and it is suitable for microwave transmission systems in field such as telemetry, communication, and electronic warfare.

Abstract：Aiming at the problems of difficult data measurement and low accuracy in the extreme environment of rocket skid test, a multi-channel, high-precision data acquisition and storage system based on FPGA is designed. The system can regulate the analog signal output by the sensor, use FPGA as the main control chip, control two AD7606 chips to synchronize the acquisition of 12 channels, and process the collected data in real time and store it to the Flash chip. The PC host can read back the data stored to Flash and map the data. And through the sealing process, the system has the characteristics of high impact resistance, high overload. The test shows that the system realizes the real-time synchronous collection of 12 channels, and the non-linear error of the measurement results is not more than 1%, which can meet the reliability requirements of data collection and storage in the rocket skid test environment.

Abstract：Aiming at the requirements of high-precision trigger control, timing control, and real-time performance in marine seismic exploration integrated navigation systems, a navigation operation control system based on the CPCI bus architecture has been designed. This system incorporates a built-in GNSS receiver and achieves high-precision clock maintenance through GPS time, FPGA and embedded software. The system utilizes a star topology differential line for high-speed serial transmission interface communication, supporting up to 24 serial port data connections. The high-precision trigger module and time-stamp matching rules enable real-time and precise control of external equipment. This paper focuses on the interface, module structure, embedded software, and experimental results. System test shows that the platform fulfills the requirements for high-precision timing and operation process sequence control in marine seismic exploration. The system is modularly designed, offering excellent scalability and modular encapsulation, and serves as a valuable reference for the development of other industrial control system.

Abstract：Satellite power systems using direct energy transmission have the advantages of simple circuit structure and high reliability, but the solar array energy utilization rate is low. In contrast, using maximum power point tracking technology can maximize the output power of the solar array, but the control is relatively complex and there is a risk of open circuit high voltage. This article proposes a MPPT (Maximum Power Point Tracking) and S3R (Sequential Switching Shunt Regulator) fusion topology power controller, which improves the energy utilization of the solar array while ensuring the reliability of the system and avoiding the open-circuit high voltage problem of the solar array. This article introduces the system composition, mode switching method, and maximum power point tracking principle of the proposed power controller in detail, and builds a test prototype for experimental verification. The experimental results prove the correctness of the theoretical analysis.

Abstract：The charging protocol for domestic electric vehicles is different from that of the European Union and other countries, and a charging communication controller that meets EU standards must be installed before it can be exported to the EU market. If domestic electric vehicle manufacturers independently develop products based on the European standard protocol, they need to change the existing battery management system (BMS) and charging controller. The consistency and interoperability of the protocol are difficult to improve in the short term, and continuous improvement, verification, and optimization are required, resulting in huge research and development time costs. In view of this, domestic MCU and PLC chip were selected to design an electric vehicle communication control system based on ISO15118. It can be converted into PLC communication that meets the European standard ISO15118 protocol and DIN70121 protocol by using GB/T 27930 protocol for CAN communication with domestic electric vehicles. Practical application shows that the system supports PnC, meets the communication security mechanism of ISO15118 protocol, has good compatibility, strong interoperability, low cost, and is convenient and flexible to use.

Abstract：In the network communication control system of rail transit, in order to ensure the stability of vehicle control and the accuracy and reliability of operation data and fault records, the central control unit (CCU) and event record machine (ERM), the key components, adopt an embedded real-time operating system VxWorks. Generally, when the system starts, it needs to start the DOS first, and then it is started as a general software call. In this paper, based on the system startup failure and the failure of 6 lights on the front panel, it studies the influence of DOS reading and writing to the electronic disk on its startup process, and proposes and validates a solution that can directly start on the FAT32 format electronic disk to avoid the problem of system startup failure. Then, according to the problems of UDP unicast, FTP file transfer, DBR startup check and LBA sector read and write in different versions of VxWorks encountered by the author, the solutions are put forward.