最新刊期
卷 ， 期 3 ， 1979
- 摘要：The meaning of the title of this review is two-fold; on the one hand, it reflects the general trend towards higher and higher frequencies in the development of modern electronics, particularly the effort made in spanning the microwave infrared gap, and on the other hand, it implies the union of microwaves and optics, which yields Microwave Optics as an interdisciplinary field of study. The paper includes the following sub-titles:1.The early union of microwaves and optice, and its later development: （1） The initial thought of microwave optics; （2 ） The development of microwave optics.2.Spanning the spectrum from microwaves to optics:（ 1 ） The microwaveinfrared gap; （2）The breakthrough of gyrotron and the outgrowth of high-energy or relativistic electronics.3.Microwave optics and the modern optical fiber theories:（ 1 ） Modal theory vs ray theory! （ 2 ） Single-mode and multimode fibers; （ 3 ） Mode couplings; （ 4 ） Measurable quantities; （ 5 ） Quantum theory and formal quantum theory.The author endeavours to describe the evolution of the physical ideas relevant to the variety of problems discussed, and presents some points of view hitherto not explicitely expressed, or not sufficiently emphasized, in the literature.2|147|5更新时间：2025-12-08
- 摘要：This article attempts to propose theoretical computing formulas for input offset voltage and common mode rejection ratio of common emitter differential amplifier, common emitter-common base differential cascode amplifier and common emitter-common grid differential cascode amplifier. It proves that Early effect plays an important role so far as input offset and common mode rejection characteristics are concerned.In the past analysis on differential amplifiers offset characteristic and common mode rejection characteristic have been separately dealt with as two different questions. And, in discussing offset characteristic the existance of Early effect, the essence of the matter has been neglected. However, if Early effect if analyzed as the leading factor, input offset characteristic and common mode characteristic of differential amplifier will fundamentally be unified in conception. Such an analysis will clearly show how differential amplifier circuits have been developed.The results thus obtained have led to the design of low drift operational module. The article analyzes the drift contribution to the input offset voltage from the nonideal characteristic of the following stage and gives the method to match low drift.In this operational module, open loop gain and common mode rejection ratio are no less than 120dB and offset voltage drift is no more than ?±0.5μV/℃. Hence, it can be used as high quality general purpose operational devices for automatic control and automatic detecting system.2|30|7更新时间：2025-12-08
- 摘要：A PNPN type negative-resistance laser has been obtained with the following heterojunction. structure.n·GaAs/N·Ga1-xAlxAs/p·GaAs/P·Ga1-yAly As/p·GaAs/n·GaAs/P·Ga1-z AlzAs where x=0.2-0.3, y≤0.20,z≈0.10. The operation mechanism and the process technology of this type of devices are discussed, The condition for "on" turning is analyzed and some electrical parameters and stimulated emission characteristics of the devices are measured. These devices have a turn-on voltage of about 15-20V, and the stand-on current is about 10100mA, while the corresponding stand-on voltage is about 1.5V. The lowest threshold current density is about 2500A/cm2. Stimulated emission by self-oseillations may easily be realized when the device is connected in a simple relaxation circuit.3|30|1更新时间：2025-12-08
- 摘要：By concise mathematical explanations and experimental results, a new structure of latching ferrite rectangular waveguide phase shifter is first introduced in this paper. Theoretical results have been proved to be basically identical with experiments.It can be applied to several types of latching ferrite rectangular waveguide phase shifters, such as dielectric-loaded, orthogonal twin-ridged and twin-toroidal phase shifters. In particular, it is most suitable for high average power.2|124|30更新时间：2025-12-08
- 摘要：Based on the fact that superimposed region of ultrasonic pulses by transmitting IDT and by receiving IDT is variable with time, a new theoretical method has been found to analyze double dispersive SAW devices. Using this simple and exact method, the effects of weighting manner, taper length and cutting digit on devices performances have been both theoretically and experimetally investigated. Two types of compression filters with center frequency of 60MHz, bandwidth of 12MHz and time delay cf 7μs to 12μs have been reported.4|23|2更新时间：2025-12-08
- 摘要：The control of the changing of pupil area with light intensity has been considered as an automatic process. An infrared instrument television has been designed for the remote measurment of the dynamic pupil area. The experimental results show that the present design is successful. This instrument provides a means to study the pupillary area control system from the point of view of biocybernetics and would be helpful to clinical diagnosis.2|37|9更新时间：2025-12-08
- 摘要：By following the equivalent linear system model[1], general expressions of autocorrelation functions and power spectrums of complex codes have been derived. The complex codes are formed by N-times clock codes which are digitally modulated by PN codes. This method is applicable both to odd and even multiple numbers of clock code frequency. By way of illustratrating the method, a particular kind of complex codes is given.2|28|0更新时间：2025-12-08
- 摘要：<正> 中国电子学会第二届年会于七月十五日至二十三日在辽宁省旅大市召开。这届年会,是在学会活动中断十七年后召开的一次规模较大的会议。任务是听取和审查学会的工作报告;进行学术交流;修订本会会章;协商增补理事会理事。 出席这届年会的有学会理事,各省、市、自治区科学技术协会和电子学会的负责同志,2|20|0更新时间：2025-12-08
- 摘要：The mathematical derivation of the formulae used for calculation of the characteristic impedances of the coaxial branched strip lines are given. The characteristic impedances of vertical,symmetrical, flat coupled strip lines are also given.2|24|1更新时间：2025-12-08
- 摘要：To deal with the problems in unequal spaced arrays, a new mathematical procedure has been illustrated. A mathematical expression has been formulated for linear arrays, by summarizing the expressions by S. A. Schelkuneff and setting the array synthesis to zero. Several types of unequal spaced arrays have been described.2|39|0更新时间：2025-12-08
- 摘要：A special shielded microsirip line is suggested.it may be analysed by the method of stripline.2|39|1更新时间：2025-12-08
- 摘要：<正> 在5cm波段GaAs FET研究的基础上,采用氧离子注入代替化学腐蚀台面作隔离,用普通接触式光刻曝光一金属剥离技术制作0.8～1.μ的栅条,并采用深挖槽等方法,我们已试制出3cm的GaAs FET。这种用生陶瓷管壳封装的器件,在10GHz下,噪声系数NF=4.7dB、增益GNF=4.7dB,或者NF=5.8dB、GNF=7dB。其管芯照片示于下图。4|18|0更新时间：2025-12-08
- 摘要：<正> 光笔图形显示器及其基本软件系统,是计算机辅助设计（CAD）的有力工具。本系统是专为CAD而设计的,它在船舶的线型设计、齿轮传动设计,以及飞机制造的工夹具设计中,已作了初步应用,效果较好。本文选用四帧从荧光屏上拍摄的照片（见文后附图）,以供参考。 本系统采用子程序包形式,而没有采取图象语言,因而有较大的灵活性:可根据需要对子程序进行2|16|0更新时间：2025-12-08
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