高速数据抗干扰传输的设计与仿真

文章提出了一种采用正交循环码的M—ary扩频多载波传输方案（M—ary／OFDM）,给出了方案的系统模型、信号格式及关键部分的设计。在发端,每个用户采用正交循环码实现M—ary扩频后经OFDM调制,在收端,经OFDM解凋后利用两个数字匹配滤波器来完成M元扩频信号的解扩,实现了高速数据的抗干扰传输。仿真结果表明,在无人机信道中该方案与传统M—ary／QPSK方案相比,具有较强的抗多径干扰及多普勒频移的能力。     

a-Si：H TFT OLED驱动电路中存储电容对显示性能的影响

对OLED两管a-Si: H有源驱动技术中存储电容对器件寿命的影响进行了详细的讨论;结合驱动管的宽长比,从理论分析和SPICE模拟两个方面研究了存储电容对电路充电率、跳变电压和保持特性的影响,找出其间相互制约的数量关系,最后给出优化设计的参考值.     

机载火控系统动态精度分析模型研究

指出当前武器系统精度分析技术相对滞后,针对机载反舰导弹火控系统的动态精度试验和数据的分析处理,提出一种武器系统火控动态精度分析新方法。通过分析火控系统动态精度试验的误差数据,建立动态误差数据序列的AR模型,引入时间序列判别函数对火控系统精度进行判定。对试验数据建模时,根据对火控动态精度误差数据的分析,分别基于高斯平稳随机假设和非高斯随机假设建立AR模型,两种模型性质不同,后者采用高阶累积量估计模型参数。该方法与常用的3σ检测准则相比,充分利用参照系统的数据和全面考虑测试数据的分布类型,能比较准确地评估系统动态精度。     

具有负反馈的分段曲率校正CMOS带隙基准源

提出了一种新型带有负反馈的分段曲率校正带隙电压基准源,该基准源的主要特色是利用温度相关的电阻比技术获得一个分段曲率校正电流,校正了一阶带隙基准源的非线性温度特性. 该分段线性电流产生电路还形成了一个负反馈,以改善带隙基准源的电源抑制和线性调整率. 测试结果表明：在2.6V电源电压下,该基准源在没有采用校正的条件下,在-50~125℃温度范围内实现了最大21.2ppm/℃温度系数,电源抑制比为-60dB. 在2.6~5.6V电源电压下的线性调整率为0.8mV/V. 采用中芯国际（SMIC) 0.35μm 5V n阱数字CMOS工艺成功实现,有效芯片面积0.04mm2,其总功耗为0.18mW. 该基准源应用于3, 5V兼容的光纤接收跨阻放大器.     

掺杂二氧化钛纳米管对有机电致发光性能的影响

在聚合物电致发光器件中，通过在不同功能层中掺杂二氧化钛纳米管来改善器件的性能.由于二氧化钛纳米管具有p型传导特性，可以显著增大空穴传输层中载流子的迁移率.由于二氧化钛纳米管在发光层中可以增大发光材料分子的刚性，从而减少无辐射跃迁.当把二氧化钛纳米管掺杂到空穴缓冲层中时，由于其与有机分子的强相互作用，一方面降低了空穴的传导性，同时也减少了界面淬灭发光的缺陷态的产生. 关键词： 二氧化钛纳米管 聚合物电致发光 掺杂     

聚苯胺与还原石墨烯复合材料的微波吸收性能

采用化学氧化法制备聚苯胺与还原石墨烯复合材料。复合材料的结构、晶型和电磁参数分别通过X射线衍射仪及HP8722ES型矢量网络分析仪进行表征、测试与分析。结果表明,同聚苯胺相比,聚苯胺与还原石墨烯复合材料的介电损耗明显增加。而且在复合材料中,石墨烯的含量越大,材料的微波吸收性能越好,在频率波段（9.5~13.4GHz）反射损耗均小于-10 dB,并在频率为11.2 GHz时达到最大反射损耗-29.69 dB。聚苯胺与还原石墨烯的复合使得材料的载流子迁移率变大,吸波特性得到改善。     

SrS:Eu与SrS:Eu,Sm中电子陷阱与光存储研究

对SrS:Eu和SrS:Eu,Sm激发初始阶段的荧光上升过程和余辉进行了研究,并进一步考证其中 电子陷阱的属性.通过两种样品和两个阶段的比较,对陷阱数量和深度的变化、量子效率以 及电子俘获和释放、复合过程进行了分析,发现Sm离子并不影响陷阱的数量.利用吸收光谱 方法研究了SrS:Eu,Sm中电子由陷阱能级向导带的跃迁.通过陷阱饱和-倒空吸收谱差,即激 励吸收谱及其强度随Eu,Sm浓度的变化,探讨了掺杂浓度对陷阱浓度和光存储饱和量的影响. 结果表明Sm离子的作用是使陷阱能级加深从而能稳定地储存电子.通过激励吸收谱峰值强度 可确切地比较光存储材料在这方面的性能,并与光激励谱的测量方法作了对照. 关键词： 电子陷阱 光存储 电子俘获 光激励发光     

Performance improvement of MEH-PPV:PCBM solar cells using bathocuproine and bathophenanthroline as the buffer layers

In this work, bathocuproine (BCP) and bathophenanthroline (Bphen), commonly used in small-molecule organic solar cells (OSCs), are adopted as the buffer layers to improve the performance of the polymer solar cells (PSCs) based on poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV): [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction. By inserting BCP or Bphen between the active layer and the top cathode, all the performance parameters are dramatically improved. The power conversion efficiency is increased by about 70% and 120% with 5-nm BCP and 12-nm Bphen layers, respectively, when compared with that of the devices without any buffer layer. The performance enhancement is attributed to BCP or Bphen (i) increasing the optical field, and hence the absorption in the active layer, (ii) effectively blocking the excitons generated in MEH-PPV from quenching at organic/aluminum (Al) interface due to the large band-gap of BCP or Bphen, which results in a significant reduction in series resistance (Rs), and (iii) preventing damage to the active layer during the metal deposition. Compared with the traditional device using LiF as the buffer layer, the BCP-based devices show a comparable efficiency, while the Bphen-based devices show a much larger efficiency. This is due to the higher electron mobility in Bphen than that in BCP, which facilitates the electron transport and extraction through the buffer layer to the cathode.     

Improved performance of P3HT：PCBM solar cells by both anode modification and short-wavelength energy utilization using Tb（aca）3phen

The performance of P3HT:PCBM solar cells was improved by anode modification using spin-coated Tb(aca)3phen ultrathin films. The modification of the Tb(aca)3phen ultrathin film between the indium tin oxide(ITO) anode and the PEDOT:PSS layer resulted in a maximum power conversion efficiency(PCE) of 2.99% compared to 2.66% for the reference device, which was due to the increase in the short-circuit current density(Jsc). The PCE improvement could be attributed to the short-wavelength energy utilization and the optimized morphology of the active layers. Tb(aca)3phen with its strong down-conversion luminescence properties is suitable for the P3HT:PCBM blend active layer, and the absorption region of the ternary blend films is extended into the near ultraviolet region. Furthermore, the crystallization and the surface morphology of P3HT:PCBM films were improved with the Tb(aca)3phen ultrathin film. The ultraviolent–visible absorption spectra,atomic force microscope(AFM), and X-ray diffraction(XRD) of the films were investigated. Both anode modification and short-wavelength energy utilization using Tb(aca)3phen in P3HT:PCBM solar cells led to about a 12% PCE increase.     

红外光激励下稀土共掺杂SrS中的光存储

研究了ＳｒＳ：Ｅｕ,Ｓｍ,Ｃｅ在紫外和蓝光辐照下的光激励发光,分析了不同写入光激发下光激励发射谱的差异,发现空穴束缚对其起决定性的作用。对电子发生转移的途径和光激励及ＳｒＳ：Ｃｅ,Ｓｍ相比,ＳｒＳ：Ｅｕ,Ｓｍ,Ｃｅ在存储密度有进一步的提高。