影响骚扰功率测量结果的因素分析

实验室能力验证计划能够保证电磁兼容实验室测试结果的一致性,而比对实验是其核心部分.从骚扰功率比对实验过程中发现了对测试有重要影响的因素,并进行了后续试验.借助功率吸收钳校准数学模型,说明了测试线到屏蔽墙的距离和辅助功率吸收钳对测试的影响,并通过实验数据分析了这两种因素对测试影响的规律,最后给出了对测试结果影响的推断.     

Ni含量对Nd_2Fe_(17)磁粉吸波性能的影响

采用高能球磨和微氧化气氛热处理制备了Nd2(Fe1–xNix)17(x=0,0.05,0.15,0.50)吸波粉体,研究了Ni的含量对NdFeNi粉体的相组成和吸波性能的影响。结果表明:当x=0,0.05,0.15和0.50时,样品的组成相均是Nd2Fe17、α-Fe和Nd2O3相。NdFe样品对电磁波的损耗以介电损耗为主;NdFeNi样品对电磁波的损耗以磁损耗为主。随着Ni含量的增加,样品对微波的吸收峰逐渐向低频移动,且其反射率逐渐升高。     

新型雷达波吸收材料研究进展

综述了国内外新型雷达波吸收材料的研究进展 ,根据雷达波吸收材料的吸波机理 ,详细介绍了纳米吸波材料、宽频谱吸波材料、手性吸波材料、导电高分子吸波涂料、结构吸波材料、多晶纤维吸波涂料、电路模拟吸波材料及等离子体吸波材料的最新研究现状。     

GaAs半导体对1.06m激光的吸收响应

人射光脉冲波长为1064nm时，GaAs光导开关上的直流电场强度为10~3V/Cm。讨一论了恒定光强和高斯光强时，GaAs杂质吸收载流子浓度随时问变化;将高斯光强时的模拟结果同实验相比较，二者吻合很好。     

Effective identification of dominant fully absorbing sets for Raptor-like LDPC codes

The error-rate floor of low-density parity-check (LDPC) codes is attributed to the trapping sets of their Tanner graphs. Among them, fully absorbing sets dominantly affect the error-rate performance, especially for short blocklengths. Efficient methods to identify the dominant trapping sets of LDPC codes were thoroughly researched as exhaustively searching them is NP-hard. However, the existing methods are ineffective for Raptor-like LDPC codes, which have many types of trapping sets. An effective method to identify dominant fully absorbing sets of Raptor-like LDPC codes is proposed. The search space of the proposed algorithm is optimized into the Tanner subgraphs of the codes to afford time-efficiency and search-effectiveness. For 5G New Radio (NR) base graph (BG) 2 LDPC codes for short blocklengths, the proposed algorithm finds more dominant fully absorbing sets within one seventh of the computation time of the existing search algorithm, and its search-effectiveness is verified using importance sampling. The proposed method is also applied to 5G NR BG1 LDPC code and Advanced Television Systems Committee 3.0 type A LDPC code for large blocklengths.     

手工软钎焊工艺技术（续一）实用电子组装技术

手工软钎焊是PCB组装和返修工艺中基本的工艺技术之一。主要针对现场要求、焊接工具选择、工艺参数设定、元件组装焊接及返修拆焊等相关内容,对手工软钎焊工艺技术进行详细阐述,为手工焊接从业者提供重要参考依据。     

Improving carriers mobility in copper and iron-codoped CdO

Thin films of Fe and Cu-codoped CdO (CdO:Cu:Fe) with different Fe content and fixed Cu content were deposited in a high vacuum on glass and Si wafer substrates. These films were studied by X-ray fluorescence (XRF), X-ray diffraction (XED), optical spectroscopy, and dc-electrical measurements. The structural results show enhancement of film [1 1 1] orientation with Fe doping especially with 1.3%Fe film. Also, light doping with Fe improves the dc-conduction parameters of the CdO:Cu:Fe films so that the utmost enhancement of mobility (90.5 cm²/Vs) and conductivity (1470.6 S/cm) was found with 1.3 wt% Fe doping level. It was found that the variation in the bandgap is related to the variation in electron concentration that caused by Fe doping. For low Fe ion concentration (<1.3 wt% ), the bandgap varies according to the Moss–Burstein model.     

FDTD法分析高速集成电路芯片内互连线

本文首次利用时域有限差分(FDTD)法分析了高速集成电路芯片内半导体基片上的有耗互连传输线的电特性.文中提出了有耗吸收边界条件,推导了不同媒质交界面上的边界条件通用格式.在FDTD分析的基础上,得到传输线各种参数的频变特性,为芯片内电路模拟提供了可靠的参数.     

Ferroelectric and Magnetic Properties in Room‐Temperature Multiferroic GaxFe2−xO3 Epitaxial Thin Films

GaFeO₃‐type iron oxide is a promising room‐temperature multiferroic material due to its large magnetization. To expand its usability, controlling the ferroelectric and magnetic properties is crucial. In this study, high‐quality Ga_xFe_2–xO₃ (x = 0–1) epitaxial films are fabricated and their properties are systematically investigated. All films exhibit room‐temperature out‐of‐plane ferroelectricity, showing that the coercive electric field (E_c) decreases monotonically with x. Additionally, the films show in‐plane ferrimagnetism with a Curie temperature (T_C) >350 K at x = 0–0.6. The coercive magnetic field (H_c) decreases with x at x ≤ 0.6, but shows a constant value at x > 0.6, whereas the saturated magnetization (M_s) increases with x at x ≤ 0.6, but decreases with x at x > 0.6. X‐ray magnetic circular dichroism reveals that the large magnetization at x = 0.6 is derived from Fe³⁺ (3d⁵) at octahedral sites. The controllable range of the E_c, H_c, and M_s values at room temperature (400–800 kV cm^?1, 1–8 kOe, and 0.2–0.6 µ_B/f.u.) is very wide and differs from those of well‐known multiferroic BiFeO₃. Furthermore, the Ga_xFe_2?xO₃ films exhibit room‐temperature magnetocapacitance effects, indicating that adjusting T_C near room temperature is useful to achieve large room‐temperature magnetocapacitance behavior.     

取向硅钢高温退火样品晶粒尺寸、取向及磁性能关系的研究

采用EBSD技术测晶粒取向,结合晶粒形貌观察,研究了普通取向硅钢高温退火样品晶粒尺寸、取向分布和电磁性能的关系。结果表明,异常长大的晶粒主要为Goss取向,小晶粒取向较杂乱,晶粒尺寸与晶粒取向有一定的相关性;晶粒尺寸和晶粒取向分别对铁损和磁感影响较大。