液晶空间光调制器在阿达玛变换光谱仪中的应用研究——快速精确的解码方法

研究了液晶空间光调制器(LC-SLM)作为固定不动的编码模板应用于阿达玛变换光谱仪(HTS),提出了快速精确的解码方法,给出了由液晶空间光调制器编码模板所带来的均方根信噪比的改善.     

110kV冷绝缘高温超导电缆在故障电流下的温度计算与分析

研究了110kV冷绝缘高温超导电缆失超时,故障电流的分流情况,并以此为依据,建立了电缆在故障电流下失超时,温升与时间关系的计算模型;通过MATLAB对计算模型进行了求解,并对求解结果进行了分析;计算出了电缆在不同故障电流下,温度上升到不同值所需要的时间,进一步明确了故障电流的大小对电缆温升的影响。     

Analysis of BPSK homodyne receivers based on modified balanced optical phase-locked loop in the presence of non-negligible loop propagation delay

Optical homodyne receivers based on modified balanced optical phase-locked loop is analyzed taking into account loop propagation delay. This modified loop contains all the components of a standard BOPLL in conjunction of an additional phase modulator. This modified loop offers a much improved tracking performance and also shows good improvements in the reduction performance over previously reported methods, like, relaxed line-width requirement and improved lock-in range. This study for the first time shows the imperfect-phase-recovery-induced power penalty as a function of laser line-width with the optimum phase deviations in the presence of non-negligible loop propagation delay. It is found that in order to maintain a 10⁻¹⁰ BER system performance with ξ = 1, R = 1 A/W, P_R = −53 dBm, Δυ = 1 MHz, phase modulator sensitivity K_PM = 10 rad/V and 10° phase deviation between the two transmitted bits, the loop delay must be kept below 3 ns. Further, the required line-width with the non-negligible loop delay time is evaluated and found to be (2.1 × 10⁻³)/τ, where τ (s) is the loop delay. This number corresponds to BER = 10⁻¹⁰, imperfect phase recovery power penalty of 1 dB and phase modulator sensitivity K_PM = 20 rad/V.     

Performance gain of displacement receiver with optimized prior probability

We numerically study the performance of the displacement based quantum receiver for the discrimination of weak 3- and 4-phase-shift keyed (PSK) coherent state signals. We show that due to the nontrivial asymmetry of the receiver structure, optimization of the prior probability increases the mutual information and achieves sub-shot-noise limit discrimination. Moreover, we estimate the cutoff rate for a 4-PSK signal and confirm that the prior probability optimization shortens the code length for a given decoding error criterion. Such consideration for the asymmetric channel matrix is essential in a study of the compassable quantum receiver.     

高温超导电缆导体层电流分布研究

通过建立高温超导电缆等效电路模型,并提出电流分布等效数学方程,求得高温超导电缆导体层电流分布。绕制一根0.2m长110kV/2kA高温超导电缆样缆,并进行载流能力实验,得到各层电流分布结果。分析发现,各层电流分布的实验结果与理论计算结果吻合,从而验证电流分布计算模型的正确性,以及调整绕制角度对均匀层间分流的有效性。研究结论对以后更长高温超导电缆的载流能力分析具有一定的指导意义。     

一种带有陷波单元的高温超导滤波器设计

提出了一种带有陷波单元的新型高温超导滤波器设计结构,在输入、输出馈线附近设置陷波单元对特定频率产生陷波作用,在滤波器的传输特性上成传输零点,提高了滤波器设计的灵活性,基于这种新型结构设计了高边缘陡峭度滤波器和邻频双通带滤波器.     

基于解码技术的全息显微术研究

提出了一种利用解码技术对全息显微畸变图像进行校正的方法。把全息记录中的显微镜预放大过程作为物光波产生畸变的编码过程;在波前再现过程中,用全息记录中的预放大显微镜对再现的赝实像再次放大进行解码,从而获得清晰的全息显微图像。实验验证了该方法的有效性。     

低环径比托卡马克堆中的α粒子输运

基于当前等离子体物理，本文初步讨论了低环径比托卡马克堆中等离子体的特征。在自洽的低环径比堆芯参数下，计算了α粒子约束和损失，以及不同环径比对它们的影响。     

耐腐蚀聚合药物基体上药物的扩散释放

主要对耐腐蚀聚合药物基体上药物的整个释放过程进行解析和数值研究.数学模型为基于Fick第二法则的边值问题,分为状态Ⅰ和Ⅱ.状态Ⅰ为具有移动性扩散波头的Stefan问题,而当此扩散波头消失时,即开始状态Ⅱ.该研究工作可作为数值研究更加复杂系统的基础之一.     

Ag-Bi高温超导线材转变温度的测量

介绍了 Bi系银包套高温超导线材的电阻温度特性 ,用测电阻和电磁感应两种方法分别测量了材料的超导转变温度 ,电磁感应法测量曲线上台阶的出现表明材料中 Bi(2 2 2 3)和 Bi(2 2 12 )两相的存在。