最新刊期
卷 ， 期 5 ， 1981
- 摘要：This paper presents a new problem on the filter properties of the axial conductor loaded helix. By using the equivalent transmission network analysis, it shows that the filter properties are different from those of the structures as suggested in narrow band TWT. In this kind of structure, the TWT can be constructed not only in narrow band operation, but also can be constructed in super-wide band operation.The theoretical analysis of the axial conductor loaded helix shows that its transverse impedance can be loaded lower enough even to 50 ohms and easy matched to the external coaxial coupler directly, while at the same time, it still maintains the coupling impedance in rather higher values and obtains high gain in TWT.The one of the distinguished advantage of the filter type slow wave circuit using in TWT is its property of suppression the BWO. Axial conductor loaded helix also has such kind of property. Dr. Otto Sauseng of USA in 1970 had adopted this kind of slow wave circuit in his TWT, no BWO occured, yet he gave no explaination. Actually, as shown in this paper, the suppression of BWO is due to the filter property of the structure. The TWT when using this kind of structure shows that the operation is quite stable. The theoretical calculation method of the axial conductor loaded helix as used in USA is the S. F. Paik’s method, while in USSR the H. H. method is used. But these two methods mainly gave out the dispersion relations, no filter properties were pointed out, and no such kind of characteristics as the pass-band, the stop band, the suppression of BWO, the effect of the numbers of metalic conductor, the effect of the dimensions of the metalic conductor, and the effect of the position of the coaxial coupler, were revealed out. While in this paper, all these problems are analyzed and relations are given. Besides, the cold circuit experiment has been performed and the dispersion curve obtained is shown more close in this method than in S. F. Paik’s method, and the match of the input coupler in super-wide band is also quite well. Therefore this filter analyzing method can be used to design such kind of loaded helix for super-wide band TWT.2|24|1更新时间：2025-12-08
- 摘要：The mappings from one-dimensional data series into multidimensional array, in which the lengths of every pair of dimensions are relatively prime, are the basis of the Wino-grad Fourier Transform Algorithm （WFTA）. This paper presents a general formulation of index mappings for L-dimensional DFT from one-dimensional DFT and shows that the possible numberof these mappings is L, where φ（ · ）is the Euler function, as for each mapping the transform formulations are given. An example shows that there are several particular mappings whose input and output index mapping are identical when N = 4·5 = 20.Some doubts have been raised about the results obtained by Kolba, Parks[5] and Winograd[6] in discussing the special case L = 2.In sectionV of [5] expressions r1 = M2 （mod M1）, r2 = M1 （mod M2） should be written as r: M2=1 （mod M1）, r2 M1 =1 （mod M2）. In Section IV of [6], formulations for the index mapping （mod n） and Bk1n2+k2=As1k1n1+s2k2n2 （mod n）,should be replaced by either ,（mod n） and Bk1n2+k2=As2k1n2+s1+k2+n1 （mod n） or bj1n1+j2=ar1j1n1+r2j2n2 （mod n） and Bk1n1+k2=As1k1n1+s2k2n2 （mod n）.At 1979 IEEE Int’l Conf. on ASSP, the paper[8] by Ellioff and Orton presented the same view as this article, even though the case of general L was discussed, and the formulations ofindex mappings were only meant for two particular cases of .2|33|2更新时间：2025-12-08
- 摘要：The paper discusses the improved least square method for polynomial differentiation. The method is suitable for real-time data processing and real-time control by a computer. It covers optimal estimations of both momentary value and continuous function curve of polynomial differential. Smoothing time may be taken at the sampling time or between any two neighboring samples, For middle-point smoothing, the number of samples may be odd or even. Simple formulas of weight coefficients and estimation errors are also shown in the paper. The law of error changes is easily shown by formulas of estimation errors, which is very useful for the correct use of the least square method.2|36|6更新时间：2025-12-08
- 摘要：: It is often troublesome, or even difficult, for the narrow band system in a coherent-pulse instrumentation radar to precisely track the radial speed of the target under conditions of low pulse repetition frequency of the radar and high speed and acceleration of the target.A method is given in this paper to bring about an all digital tracking system on the basis of modified DFT. Such system can track not only the radial speed of the target, but also its acceleration directly in conditions of low repetition frequency and high target speed and acceleration.The first part of the paper describes the influence of target radial acceleration on DFT. the modified DFT which can eliminate the said influence, and the two dimensional response characteristics of the frequency and the frequency changing rate of this modified DFT. The second part explains the method of eliminating speed ambiguity by repetition frequency agility. This method is based on solving residual equations for root and does no depend on target range information. The third part deals with the narrow band tracking loop based on modified DFT. Two dimensional error characteristics of the frequency and the frequency changing rate are presented, and a block-diagram of the system is also given.The author has conducted mathematical simulation of the above system. The results show that the accuracy in the measurement of radial speed and acceleration is quite satisfactory under the condition of comparatively low signal-noise ratio.2|31|1更新时间：2025-12-08
- 摘要：In this paper the effect of junction capacitance, spontaneous recombination, DC-bias and injected pulse current on time delay’ of turn-on of injection lasers modulated by pulse currents is analysed comprehensively. Kinetic equations considering those factors are developed. A variety of possible cases for are discussed, and results for some typical parameters are given. The calculated results are found to coincide with the measured values. When the junction capacitance is not very small （>20 pF）, it is an important factor for the time delay just like spontaneous recombination. The reduction of the time delay by DC bias is not linear, becoming small gradually from zero-bias to DC-bias at threshold. Thus we can obtain the best modulation by DC-bias below threshold.2|29|0更新时间：2025-12-08
- 摘要：This paper presents a topological technique for the sensitivity calculation by means of singal flow graphs theory. In our signal flow graph, the branch gains for the input branches and the intermediate branches are the nonlinear function of the system parameter for finding the sensitivity. According to the definition of summing matrix and branching matrix, and by using the Tellegen’s theorem for singnal flow graph, the general expression has been developed. The key to this technique is to calculate the sensitivity by direct application of the topological structure of the signal flow graph. The existing results may be considered as special cases of the general expression proposed in this paper. Finally, the application of the expression is illustrated by a concrete example.2|23|2更新时间：2025-12-08
- 摘要：<正> 中国电子学会电子机械工程学会于1981年8月19日至25日在河北省承德市召开了成立大会。中国电子学会常务理事、副秘书长、组织委员会副主任委员钱文极同志,中国电子学会常务理事兼副秘书长、学术委员会主任委员、中国科学院学部委员罗沛霖同志到会并作了重要讲话。来自全国15个省市,42个厂、所、院校的54位代表参加了大会。 大会听取了会议筹备组组长、南京电子技术研究所所长兼总工程师周文盛同志关于筹备工作的汇报和钱文极同志代表中国电子学会宣读的、由中国电子学会理事会推荐的电子机械工程学会正、副主任委员及委员的名单。 到会同志对于本学会的任务,委员人选,专业学组的方向任务,正、副组长单位,1982、1983年的学2|12|0更新时间：2025-12-08
- 摘要：Many previous literatures considered that the operating frequency of an impulse governed oscillator （IGO） was difficult to be extended to the microwave band. One of the reasons put forward was that the width of the synchronizing pulse must be narrower than 1/5 to 1/3 of the period of the VCO, which was relatively difficult to achieve in the microwave band. Some recent literatures raised an objection to this, but still considered the narrower the synchronizing pulse for a microwave IGO in the case of non-ideal sample-and-hold, the better. This paper proves that neither of these conclusions is exactly true. In addition, previous literatures also doubted the loop stability of IGO, and held that its phase noise might be greater than that of a common phase lock loop. This paper discusses the problems concerning phase noise and loop stability. Theoretical analysis and an IGO experiment at 3GHz show that a correctly designed microwave IGO has low phase noise, better stability and a simpler, compact strip-line structure. Therefore further advances of the IGO may be expected.2|48|3更新时间：2025-12-08
- 摘要：With electromagnetic field theory, formation of the impedance of a YIG single crystal sphere resonator coupled by a loop is analyzed in this paper, When the diameter of a single crystal sphere can be compared with the diameter of a loop, a general formula of resonator impedance is derived.Considering that the surface of the magnetic pole is an ideal magnetic wall, by means of mirror method, the effect of outer magnetic pole on resonator impedance is analyzed quantitatively. The resonator impadance formula derived by author differs from those of references [1],[2],[3] slightly and proves that the impedance formulae given in references [4], [5] are only suitable for the case that the radius of the single crystal sphere is much less than that of a loop.2|24|0更新时间：2025-12-08
- 摘要：Some experimental results of a x-ray preionized homogeneous discharge laser at high gas pressures are presented. In this device a multi-arc-channel rail gap switch is used to create a fast voltage rise time, and a water-dielectric transmission line is employed as the discharge energy source. Homogeneous discharge lasts about 70 ns in a typical XeCl* gas mixture of 2-5 atm, and a laser output energy higher than 1.2 joules has been obtained in an active volume ot 2.0×1.5×70 cm3.2|24|1更新时间：2025-12-08
- 摘要：Based on the laser oscillation requirements, this paper discusses the condition for increasing pulse-width of excimer laser. In principle, CW operation of excimer laser can be obtained. For example, if dc discharge current density J≥5A/cm2, the XeF* excimer laser can produce CW output. But, under this discharge level, arc discharge is likely to occur and as a result of arc discharge, laser oscillation will be interrupted. The problem may be solved if an electron beam source is used. However, it is rather difficult now to make high power electron beam soure.2|59|0更新时间：2025-12-08
- 摘要：A further theoretical analysis of crosstalk between two lines is given. This paper presents the theoretical formulae for calculation of wave for crosstalk between two lines with arbitrary input signal function and arbitrary termination impedance. The practical applications are illustrated by an example.2|142|3更新时间：2025-12-08
- 摘要："Gray Scale Sync" is a new technology which can not only implement the "So-und-in-Sync" technique effectively but also improve the signal to noise ratio of the TV picture by 3 dB. Based on the study of the digital processing of the TV sync and sound signals, we have developed a "Gray Scale Sync" equipment capable of handling the PAL format composite colour TV signals and also suitable to the reception of overdeviation signals. In this treatise, stress is laid on the explanation of the scheme and the result of the experiments.2|24|0更新时间：2025-12-08
- 摘要：Alterative proofs of two theorems concerning the existence and uniqueness of solutions for nonlinear resistive circuit are given. Colored branch theorem is used to facilitate the test of the condition which must be satisfied by norm.2|62|0更新时间：2025-12-08
- 摘要：This paper describes a new scheme and an experimental system to realize high precision microwave phase calibration by directly heterodyning microwave to low frequency, and using a low frequency inductive phase shifter asз. standard reference. The accuracy obtained is 0.1 at 5cm band, and can be increased to ±0.02 using the author’s frequency-division method. Some ideas are given to error checking and the selfcalibation techniques.2|14|1更新时间：2025-12-08
- 摘要：This paper discusses the concepts about the fault tree’s dual tree and success tree as follows: 1) The dual tree and the success tree are two different concepts. 2) If the fault tree’s mathematical expression is （X）, then its dual tree’s mathematical expression will be defined as D（X） = 1 - （1 - X）, the relationship between the fault tree and its dual tree being that their "gates" are different, "AND" "OR", and their "bottom events" are completely identical. At the same time, the cut set of the dual tree is the path set of the faulttree and vice versa. 3) The success tree’s mathematical expression is （X） = 1 - （X）, the relationship between the fault tree and its success tree being that their "gates" are different, "AND" "OR", and their "bottom events" are also different and complementary. Strictly speaking, the cut set of the success tree is not the path set of the fault tree and vice versa.2|64|4更新时间：2025-12-08
- 摘要：This paper analyses the dual-ramp A to D converter error due to dielectric absorption of the integrator capacitor with a rigorous mathematical method. It is proved that if the dual-ramp A to D converter runs continuously and if same voltage have been measured for a sufficiently long time the dielectric absorption of the integrator capacitor will not cause any error. When measured voltage changes abruptly the dielectric absorption of capacitor will cause error for first a few measurements. The formula for calculating error and its time constant is obtained.2|53|1更新时间：2025-12-08
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