Based on the theory mode , the delay time between the beginning of optical illumination and the onset of lock - on switching was calculated , and the transiting speed of electrons , the traversing velocity of the current filament , was obtained as well . the calculated results matched well the experimental results . taking advantage of the ultra - fast response characteristics of the devices , si - gaas pcss ' s are successfully applied to the broadening test of nanosecond laser pulses 应用单极电荷畴模型数值计算了lock - on效应的光、电时间延迟和载流子的渡西安理工大学硕士学位论文越速度（丝状电流穿越开关间隙的速度） ，所得计算结果与实验测试结果基本吻a利川半绝缘gaas光屯导开关的超快光l匕11向应灯性，成功地应川下纳秒激光脉冲展宽试验中，证明了开关可厂泛应川在超快光电响应和光电反馈网络中。
Duo to the intrinsic characteristics of the gaas material , serai - insulating ( si ) gaas photoconductive semiconductor switches ( pcss " s ) have more obvious advantages in the performance of both high power and ultra - fast switching than those pcss " s made of other materials and then can be widely used in ultrahigh speed electronics , field of high power microwave generation and pulse forming ( pulse sources of high power ultra - fast electromagnetism , ultra - wide - band microwave generator ) 半绝缘gaas光电导开关( photoconductivesemiconductorswitches简称pcss ' s )具有兼备宽频带和高功率容量特性，使其在超高速电子学和大功率脉冲产生与整形技术领域(大功率亚纳秒脉冲源、超宽带射频发生器等)具有广泛应用前景。
This dissertation is mainly concerned about the radiation of the tem - horn arrays which radiate uwb ( ultra wideband ) pulse , it mainly involves three parts : theory , numerical stimulation and experiment . the uwb antenna is a new research field in the world which has many differences from nb ( narrow band ) antenna . the most difference is that the uwb antenna such as tem - horn radiates nanosecond pulse which has wide frequency spectrum , but the nb antenna radiates single frequency signal 超宽带天线是一项新兴的研究领域，它与窄带天线有很多不同之处，最根本的不同在于：超宽带天线例如tem喇叭天线是辐射纳秒级短脉冲信号，这种脉冲信号有很宽的频谱；而窄带天线大都是辐射单一频率时谐信号的。
It is a novel short - distance wireless communication technique , in which data are transferred using non - sinusoidal pulses with very short duration , so it is fit for using in indoor environments which is a typical multipath environment . and it can be coexisted with the existing wireless communication systems at the same frequency band 超宽带通信系统利用纳秒至皮秒级的非正弦波窄脉冲传输数据,非常适合作为城区及室内密集多径环境下的应用,并且能够与现有的传统窄带系统共存。
The second harmonic produced by a q - switched nd : yag laser with wavelength e = 532 nanometers ( nm ) , pulse width 0 nanoseconds ( ns ) and repetition frequency i = 1 hz was used to bombard a highly pure solid hexagonal bn ( h - bn ) target ( 96 % ) , with diameter of 2cm . in a vacuum chamber , boron nitride ( bn ) film was deposited on the single - crystal silicon substrate 利用高能脉冲激光(波长= 532nm ，频率= 1赫兹，脉宽= 10纳秒)在常温下轰击烧结的高纯六方氮化硼( h - bn )靶，在真空反应室中将bn薄膜沉积在单晶硅基底上。
