Electro-optic diffraction grating for light beam modulation and diffraction

The interaction between a strong traveling microwave signal and an optical beam in an electro-optic material is described in the limit of very high microwave dielectric constant. The interaction produces effects analogous to those produced by a moving diffraction grating. When the optical beam is wider than the wavelength of the microwave signal, the first grating order is resolved from the zero-order or main beam. Under this condition two types of devices become possible: 1) a beam deflector which can position an optical maser beam on, for example, 10⁵distinct points with negligible crosstalk and with address times of order 10^-7s, 2) a baseband light intensity modulator which is founded on the fact that light deflected into the first-order beam by the microwave signal is removed from the main beam. The amount deflected into the first-order beam is proportional to the microwave power; the intensity modulation follows the microwave envelope. The power required for a given modulation depth is inversely proportional to the seven halfs power of the dielectric Constant. As an example, for a not unrealistic choice of dielectric constant of 10⁴, complete transfer from the zero-order to the first-order beam requires 5 watts of microwave power. The interaction length is of order one centimeter and the interaction bandwidth is essentially unlimited. As a baseband modulator the maximum instantaneous bandwidth is of order 10 percent of the subcarrier frequency. Experimental verification is provided in an earlier paper [1].     

波导相位调制器光谱展宽特性分析及实验研究

计算了相位调制器光谱展宽与调制深度的关系，分析并通过实验观察了０．６３２８μｍ光辐射在功率１Ｗ，２．４５ＧＨｚ微波驱动下的频谱，推得调制深度与微波功率的表达式。最后用光栅谱仪测得在１６Ｗ微波功率作用下产生０．１３ｎｍ光谱宽度，两种测试结果吻合较好。     

温变参数材料微波加热的数值模拟

针对一般材料的介电参数等温度的函数，本文提出了一个微波加热分析的非线性模型。该模型基于交替迭代法求解描述加热过程的非线性耦合电磁学，热学微分方程组，通过若干数值分析的实例，说明了该方法可作为微波加热精确分析的一个有效方法。     

Temperature dependence of POPOP dye vapor lasers

The pure POPOP dye vapor is excited in a transverse geometry by an N2laser and the output power of the laser is measured as a function of temperature and intensity of the exciting laser. The threshold temperature is about 310°C and the maximum output power is obtained at around 390°C. The threshold intensity of the exciting laser is about 0.3 MW/cm²and the output power is almost linearly dependent on the intensity as far as experimentally observed. The shift of the oscillation wavelength is observed with increasing temperature and the central wavelength of the broad-band laser can be tuned from 385 to 402 nm by the selection of the vapor density. Theoretical results calculated from rate equations which are dependent on time and space qualitatively agree with these experimental results. The effect of reflectance of the cavity on the output power is also discussed.     

Temperature dependence of POPOP dye vapor lasers

The pure POPOP dye vapor is excited in a transverse geometry by an N2laser and the output power of the laser is measured as a function of temperature and intensity of the exciting laser. The threshold temperature is about 310°C and the maximum output power is obtained at around 390°C. The threshold intensity of the exciting laser is about 0.3 MW/cm²and the output power is almost linearly dependent on the intensity as far as experimentally observed. The shift of the oscillation wavelength is observed with increasing temperature and the central wavelength of the broad-band laser can be tuned from 385 to 402 nm by the selection of the vapor density. Theoretical results calculated from rate equations which are dependent on time and space qualitatively agree with these experimental results. The effect of reflectance of the cavity on the output power is also discussed.     

一种X波段宽带T/R组件的实现

介绍了一种宽带X波段四通道T/R组件的实现方法。在小尺寸空间中包含了微波电路、DC/DC电源、波束控制、功率故障检测和温度监测功能。结构上输入输出、加电端口均设计在同一侧。对组件复杂功能和特殊结构以及由此带来的工艺装配问题进行了分析和阐述,并研制出符合各项指标要求的宽带X波段T/R组件,该组件有完善的工艺措施来保证,性能好、重量轻、可靠性高;通过电性能和结构性能指标的测试,达到了总体技术要求。     

微波辐射多钒酸铵制备V2O5的研究

实验研究了多钒酸铵(APV)的微波加热和分解过程,探索了微波功率、APV质量及其水分质量分数等对APV转化成V2O5效率的影响。结果表明,APV是可吸收微波的物质,但其水分、质量及微波功率等因素对平均加热速度有较大影响。采用微波加热法可完成APV的脱水和脱氨过程。     

脉冲工作状态下微波功率管瞬态特性研究

鉴于越来越多的领域要求微波功率管工作于脉冲应用状态,研究管子的瞬态温度特性就显得日益重要。假设热源为一无限大平面,且在芯片表面热源产生的热量只沿垂直于芯片表面一维地传递。从这一简化的理想热传导模型出发,对热传导方程离散化;在热沉端,定义了能够与实际情况相吻合的温度上升与下降时间常数来确定边界条件,从而得到了在脉冲应用情况下,芯片表面瞬态温度随时间变化的计算机模拟结果。通过在连续波工作下与红外显微镜实测温度的比较,验证了模拟程序的准确性,并且给出了最高结温随时间、脉宽、占空比的拟合公式。为微波脉冲功率晶体管的设计提供了育价值的参考。     

Nonlinear properties of IMPATT devices

The basic principles of IMPATT diodes as microwave devices are reviewed and the current status of these devices concerning power output and efficiency is given. The main purpose of this paper, however, is to discuss the nonlinear properties of these diodes which are useful in the design of amplifiers, oscillators, and other microwave devices. The main results of this paper are obtained from a digital computer analysis where an approximate, but realistic, diode model is employed. A detailed comparison of complementary silicon diodes as well as GaAs diodes concerning power output and efficiency is given. The effects of doping profile, current density, temperature, and material parameters on the performance of these devices have been investigated and are summarized. Saturation effects which limit the efficiency and power output of these devices are described and optimum efficiencies which can be achieved for various doping profiles are given. A comparison between single-sided and double-drift diodes in both silicon and GaAs is also presented.