Microwave Integrated Circuits--An Historical Perspective

Before attempting an historical view of microwave integrated circuits, it was necessary to consider just what a microwave integrated circuit is. If someone can come up with a clear, noncontroversial, universally accepted definition, he's a better man than I am. In the broadest sense, a microwave integrated circuit is any combination of circuit functions which are packaged together without a user accessible interface. This definition, however, opens the door to great kluges of waveguide bends and components which have been brazed or welded together, and that is clearly not the intent of this review. I have, therefore, limited the scope to planar integrated circuits which make use of process control manufacturing techniques for a significant portion of the integrated circuit, This would include such transmission-line techniques as stripline, rnicrostrip, slotline, finline, co-planar waveguide, and to a slightly lesser extent, lumped element circuits, image guide dielectric waveguides, and planar waveguide packages which are becoming a viable technique for integrated circuits at millimeter-wave frequencies.     

Microwave Instrumentation: An Historical Perspective

Metrology is the science of measurements. When one is making a measurement, one is comparing an unknown quantity of some measure with a known (calibrated) quantity of the same measure. The equipment being used in electronics, especially in microwaves, is called instrumentation. When making measurements, using the appropriate instrumentation, the basic rules of metrology have to be observed. It is not enough to gather the data by performing the test; an evaluation of the errors involved also has to be determined. Resolution, readability, repeatability, and absolute calibration accuracy are all important factors in these considerations. It was exactly the evolution of these factors (the need for better accuracy and more data points by systems engineers) which fueled this process. When the measurement techniques fulfilled the requirements of systems designers, better, more sophisticated systems were possible to invent, which in turn posed the need for more improvements in instrumentation.     

Monolithic Microwave Integrated Circuits: An Historical Perspective

Monolithic microwave integrated-circuit (MMIC) technology as it exists today has evolved from events that occurred during the middle-to-late 1950's and early 1960's. These events are reconstructed through a review of the published literature, government contract reports and proposals, U.S. patents, and private communications with individuals directly involved in early MMIC development. No single point in time can be viewed as that historical moment when the idea of an MMIC was formalized; rather, the idea evolved over a period of time as a direct result of the successful development of analog and digital IC's and the push by the military services (primarily the Air Force at Wright Patterson) to apply semiconductor technology in defense systems, the evolutionary period is presented in chronological order and includes a discussion of the role played by the Molecular Electronics for Radar Applications program. Early development activities were pursued, with both silicon and GaAs used as the monolithic material. These activities, the early problems encountered with both materials, and the influence the problems had in molding today's technology are described.     

Historical Perspectives on Microwave Field Theory

Microwave Field Theory furnishes the foundation for all of the microwave circuitry that made possible the great advances achieved by the microwave field. It is important to understand that microwave field theory is only a portion of electromagnetic field theory in general, and to appreciate how it is distinguished from it. In addition, the network formulation of microwave field theory has been fundamental to the rapid progress made by the microwave community; the formulation in network terms has been so intertwined with the development and understanding of the field concepts and behavior that the network formulation should be viewed as an integral part of microwave field theory. The first part of this introduction explains the point of view indicated in the above paragraph. The second part of the introduction outlines the scope of the historical review presented here.     

Microwave Printed Circuits - A Historical Survey

The microwave printed circuit, as described in this paper, is an extension of the well-known technique which is of such importance in the lower frequency regions, where lumped element circuits are practical. This new circuit possesses all of the virtues of other printed circuits, such as light weight, cheapness, ease of manufacture, miniaturization, etc., along with the ability to be used at frequencies as high as 10,000 mc. The basis of the new technique is the planar or "flat strip" coaxial transmission system which was developed during World War II but which has remained unpublished and relatively unknown in the postwar period; and for which an adequate theoretical analysis had not been available.     

Fiber-Optic Sensing: A Historical Perspective

Sensing via fiber optics has occupied R&D groups for over 40 years, and some important transitions into the commercial sector have been achieved. We look at the fundamental concepts involved in the various sensing approaches, and the differentiators which have led to commercial impact. We also look to the future of fiber-optic sensors.     

Advances in Optical Fiber Communications: An Historical Perspective

Following a decade of intensive research, optical fiber transmission emerged in the late 1970's as a major innovation in telecommunications. This paper reviews the progress in the field of optical fiber communication. Advances in the areas of fibers, cables, passive components, active devices, and systems are presented in historical perspective. Recent research and development accomplishments that are likely to have important impact on future systems are emphasized.     

Evolution and Impact of Wi-Fi Technology and Applications: A Historical Perspective

International Journal of Wireless Information Networks - The IEEE 802.11 standard for wireless local area networking (WLAN), commercially known as Wi-Fi, has become a necessity in our day-to-day...     

《科学月刊》的“历史定位”——一个科学史家的个人观点

《科学月刊》于1970年元旦创刊,至今已留下了40余年闪光的足迹。在《科学月刊》创刊届满40周年之际,笔者从一名科学史家的角度出发,据个人多年在《科学月刊》工作中的观察领会,从刊物创办的时机、精英主义、科学写作议题、科学社群的组织工作等几方面一一做了回顾,就《科学月刊》的"历史定位",提出了一些个人的观点。     

Standardization of Propagation Models for Terrestrial Cellular Systems: A Historical Perspective

Propagation models constitute a fundamental building block of wireless communications research. Before we build and operate real systems, we must understand the science of radio propagation, and develop channel models that both reflect the important propagation processes and allow a fair comparison of different systems. In the past five decades, wireless systems have gone through five generations, from supporting voice applications to enhanced mobile broadband. To meet the ever increasing data rate demands of wireless systems, frequency bands covering a wide range from 800 MHz to 100 GHz have been allocated for use. The standardization of these systems started in the early/mid 1980s in Europe by the European Telecommunications Standards Institute with the advent of Global System for Mobile Communications. This motivated the development of the first standardized propagation model by the European Cooperation in Science and Technology (COST) 207 working group. These standardization activities were continued and expanded for the third, fourth, and fifth generations of COST, as well as by the Third Generation Partnership Project, and the International Telecommnunication Union. This paper presents a historical overview of the standardized propagation models covering first to fifth-generation systems. In particular, we discuss the evolution and standardization of pathloss models, as well as large and small-scale fading parameters for single antenna and multiple antenna systems. Furthermore, we present insights into the progress of deterministic modelling across the five generations of systems, as well as discuss more advanced modelling components needed for the detailed simulations of millimeter-wave channels. A comprehensive bibliography at the end of the paper will aid the interested reader to dig deeper.

     

Thermal Interface Materials: Historical Perspective, Status, and Future Directions

With the continual increase in cooling demand for microprocessors, there has been an increased focus within the microelectronics industry on developing thermal solutions. Thermal interface materials (TIMs) play a key role in thermally connecting various components of the thermal solution. Review of the progress made in the area of TIMs in the past five years is presented. The focus is on the rheology-based modeling and design of polymeric TIMs due to their widespread use. Review of limited literature on the thermal performance of solders is also provided. Merits and demerits of using nanoparticles and nanotubes for TIM applications are also discussed. I conclude the paper with some directions for the future that I feel are relatively untouched and potentially very beneficial.     

我国微波技术与微波通信的进展

本文论述我国在微波通信领域已取得或正在开展的一些基础性研究工作以及发展状况。包括微波技术方面的发展水平；微波通信的几种主要形式及其发展水平。     

微波功率模块微波特性的研究

集成固态/真空电子技术的微波功率模块(MPM)是新一代电子武器装备的"超级微波元器件".文中对MPM微波特性进行了研究,由于行波管(TWT)良好的色散特性,使MPM具有宽频带和功率、带宽乘积的优点;又由于固态放大器(SSA)低噪声性能,使MPM具有低噪声特性;高稳定的集成电源(IPC)决定了MPM具有低相位噪声与低杂散的频谱特性,合理的增益分配也使得MPM具有良好噪声特性.文中具体分析了集成电源(IPC)性能对频谱特性的影响,SSA与TWT噪声特性、增益分配对MPM噪声特性的影响,MPM幅相一致性和功率合成效率问题,并给出了仿真曲线,通过对某X波段MPM微波特性测试,验证了MPM优越的性能,也充分表明了MPM具有广泛的应用前景.     

微波等离子灯微波系统的改进

传输微波的波导和形成谐振腔的网罩足微波等离子灯中的核心部件,本文重点阐述这两部分微波系统的仿真优化设计.文章首先分析了最早所采用的微波传输系统,给出仿真结果论证,然后介绍和参考了国外优秀的波导及谐振腔设计方案,给出理论分析,最终依据以上综合分析提出新型波导系统以及新型谐振腔的设计,其中部分新型设计已在实际应用中取得了很好的效果,其它新型设计还将继续研究,如文中提到的脊型谐振腔和半椭球谐振腔.