最新刊期
卷 ， 期 4 ， 1983
- 摘要：Abstract: Electric communication is vital to economic construction and social development of the country, not only does it provide a high revenue directly, amounting to several percent of GNP, but it also creates an integrated, sometimes indirectly, social results which are even more rewarding. It is indeed the infrastructure of the society, necessitating to take great efforts for its consolidation. This paper points out the serious lag-behind of the present communication technologies of China through a brief review of the status of developed countries and our country during 1970’s and early 1980’s. Some remarks are made from strategic point of view to improve this situation.2|15|0更新时间：2025-12-08
- 摘要：This paper gives a brief review on the history of the education of communication engineering in China, which has been developed rapidly since 1949. And some suggestions for the improvement of it are also introduced.2|26|0更新时间：2025-12-08
- 摘要：The purpose of this paper is three-fold: （1） to establish relationships among error, jitter, wander, slip, delay, loss of frame alignment and total distortion, （2） to provide simple specification approaches for the above-mentioned transmission impairments in digital networks, and （3） to report some data presented in CCITT recommendations and contributions by administrations for the study period 1981-1984.2|14|0更新时间：2025-12-08
- 摘要：Modern communication techniques are now at the stage of digital revolution. Microwave relay communication systems are also faced with the challenge of digitalization. This paper gives a survey of the advances of digital microwave relay communication systems in China.2|88|0更新时间：2025-12-08
- 摘要：Both the status of development of international satellite communications and the advances of domestic satellite communications in other countries are reviewed. China’s recent developments in this field are briefly described. And some technical views are put forward for consideration by the country’s satellite communications engineering circles.3|56|0更新时间：2025-12-08
- 摘要：This paper consists of a Brief review of the background for the development of mobile communications, examples showing their undeniable significance in the promotion of China’s four modernizations, and some views as to their further development in China.2|19|0更新时间：2025-12-08
- 摘要：This paper reviews the troposcatter communication advances for the past thirty years or so, summarizes China’s achievements in this field, and discusses the possible trends for future developments.2|121|4更新时间：2025-12-08
- 摘要：Up to present, the design method for TWT is still those founded in the fifties and sixties of this century. In designing the TWT, it usually starts from selecting the value of γa in the range of 1.2-1.6, then calculates the related internal working parameters and the dimensions of the tube until the performances of the tube are satisfied. In such kind of design method, it can not bring the internal working parameters and the dimensions of the TWT in the suitable working region in the first run calculation. It needs the way of cut and try, and has some blindness in mind for a green hand designer.In this paper it gives out a new procedure in the design method. In this new design procedure, it starts from the small signal gain parameter working region diagram（2）, selecting a suitable working region, setting out a working point at the center of the frequency band and obtain the working point value of b, QC and x1, and then calculating the dynamic working curve of the whole frequency band. From this dynamic working curve, we can see clearly on the region diagram whether the working region fixed is satisfied or not. And on this region diagram, we can judge whether there is any possibility of performance improvements of the TWT, and if necessary, see how to move the working point to a better region. Such kind of selection and fixing on the region diagram method makes the designer’s mind clear and avoids blindness.This new procedure can be used for design of small signal gain TWT, of high efficiency and high power tube, and of super wide band TWT.2|33|1更新时间：2025-12-08
- 摘要：This paper presents a new type of PLA （R-PLA） which is made up of AND-EXCLUSIVE-OR array. The multi-channel digital networks described by vector Boolean alge- bra and the adders with parity check and parity prediction are realized very conveniently by using the R-PLA. The R-PLA is also simple for generating test codes of Boolean difference. This paper provides CAD algorithms for finding optimal or nearoptimal ring sum cover.4|19|0更新时间：2025-12-08
- 摘要：A cubic cell structure based on three value logic is proposed for the realization of common logic arrays. The essential features and design method of this structure, as well as the synthesis of the array, are discussed. And this common array is compared with both binary cell arrays and other ternary cell arrays.4|13|1更新时间：2025-12-08
- 摘要：A field analysis of a double array microstrip meander-line slow-wave structure is reported in this paper. The potential function U（y,z） and the characteristic admittance of single conductor Yc were calculated with numerical method, and the characteristic dispersion equation and the coupling impedance expression for this structure were derived. The perfor-mance of the microstrip meander-line for different structural parameters were calculated by computer. Two such lines have been used in printed circuit TWTs, experiment results come close to theoretical calculations.2|131|17更新时间：2025-12-08
- 摘要：A computer-aided design procedure applicable to low-noise and broad-band MMIC FET amplifiers is presented. The method takes into account the non-unilateral behavior of the FET, losses in the matching networks and complex termination mismatches. The design procedure is more complete and accurate than currently available CAD methods. Two design examples, an 812 GHz and a 615 GHz MMIC FET amplifiers, are presented to illustrate the applications.2|29|5更新时间：2025-12-08
- 摘要：The coefficient error and the fixed point calculation error of the digital signal processor in a TDM/FDM transmultiplexer are analyzed, so are their effects on the frequency performance and system noise of the processor. The analyzed processor adopts WFTA + Poly-phase network scheme, but the analysis method in this paper can also be applied to general DFT + polyphase network schemes. Analysis methods are also given for the fixed point calculation errors of general WFTA and of complex digital filters.2|34|0更新时间：2025-12-08
- 摘要：This paper investigates the specific optimum solution of formula （2）（6） for a linear system under the conditions of an ARMA series xt and a rational frequency response function H（λ） which can be expressed by formula （9）. The correction efficiency for the inter-symbol interference of the prefiltering in a communication system is given as an example.2|28|0更新时间：2025-12-08
- 摘要：The frequency hysteresis of the magnetically tuned YIG devices driven by two usual input signals are analyzed. The mathematical equation for the relation between the value of frequency hysteresis, the structural parameters of the and the tuning wave shape parameters of the driving signal become is established. Accordingly, the calculation of the tuning speed and the applications of the device become easy and convenient.2|37|4更新时间：2025-12-08
- 摘要：This paper analytically derives a set of general formulas from basic principles of airborne pulse-doppler radar. Using these formulas, it can easily be determined whether the moving target return is located in ground clutter region or clutter-free region.2|41|0更新时间：2025-12-08
- 摘要：A method for measuring high sensitivity current by means of current amplifier with voltage divider feedback is discussed in this paper. The limit sensitivity and stability of this current-voltage measurement circuit is analysed. On the basis of the discussion, a measurement instrument （JB-7705） of DC parameter of semiconductor devices is developed.3|52|1更新时间：2025-12-08
- 摘要：<正> In the above publication dispersion calculations have been made for monomode step-index weakly guiding optical fibers. However, as explained below the approach followed in it was. approximate and therefore the conclusions drawn therefrom as regards the accuracy of the two sets of given approximate empirical formulas for prediction of zero dispersion wave-length was. not correct.2|28|0更新时间：2025-12-08
- 摘要：<正> 四川永川固体电路研究所研制出的M4116 16kMOS DRAM、M2114 4kMOS SRAM、M2115 E/DHMOS SRAM以及S100101 3-5输入或/或非门电路等科研成果已于1983年3月通过了部级设计定型。这些电路的研制成功为我国计算机和MOS大规模集成电路、超高速ECL电路的发展开创了道路。 M4116 16kMOS DRAM 采用N沟双层多晶硅工艺制造,芯片面积3×5.6mm2,集成度37000个元件/片。电路用多路分时行、列地址输入,三态输出;数据输出由列地址选通控制并在取数时间至列地址2|10|0更新时间：2025-12-08
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