最新刊期
卷 ， 期 3 ， 1981
- 摘要：This paper extends the theory of the general parameter filter without the complex loss zeros with quadrantal symmetry. That is, the loss and the delay time characteristic of pass-bands are Chebyshev-type approximation and the loss characteristic of stopbands can be specified arbitrarily. Because the nonminimum-phase transfer function can be expressed as the product of minimum-phase transfer function and all-pass function, the loss characteristic of nonminimum-phase and corresponding minimum-phase transfer function is the same and a unique relationship exists between the loss and the phase characteristic of minimum-phase transfer function. A series of new formulas for the loss and the delay time function have been derived, and the Chebyshev-type approximation of the delay time characteristic of pass-band and the initial guess of all available parameters have been obtained. In this respect, this paper presents new ideas and methods. The results of this paper can be used to design varieties of filters including lumped LC filters, active filters, microwave filters, digital filters etc. The results have been made use of in actual applications and have shown great advantages.2|61|8更新时间：2025-12-08
- 摘要：<正> 通过近三年的努力,四机部应用磁学研究所于1980年夏季完成了一台磁泡电话自动拨码装置,并于1980年年底进行了技术鉴定,认为该装置达到了设计要求,具有国内先进水平。我所研制磁泡电话自动拨码装置的目的在于积累磁泡材料、器件工艺及应用技术等方面的实践经验。 磁泡存储器是利用一种特殊的磁性薄膜材料,采用大面积集成工艺加工成的新型磁集成器件,具有非易2|11|0更新时间：2025-12-08
- 摘要：The position system which uses an inductosyn as a transducer can measure the angle and the length very accurately. Combining it with the computer constitutes the digital servo system with high precision. This instrument has been broadly used in astronomical navigation, missile controlling, satellite tracking, radar, disk storage, and almost all kinds of precision machine tools. If the position system works in static mode, the position error of the transducer will affect the positioning precision. However, once the inductosyn has been made, its position error is fixed, hence we can test its characteristic. In this paper, the inductosyn’s positional error is analysed, and from which the mathematical model describing the positional error is formed. The computer can automatically correct the positional error through its error characteristic, so that the system’s precision of the static positioning will be improved. This is performed by software. "The program for correcting the positional error" written in ALGOL-60 is presented. Because the method is applicable, in principle, to the multipolar rotary transformer, it will be able to make higher precision position system by use of lower precision transducer.When the position system works in dynamic mode （e. g. to measure the antenna’s azimuth）, as soon as the system has received the return from an object, the computer must immediately read the antenna’s azimuth for computing the coordinate of the object at the moment. Because of the delay in the course of tracking, a dynamic error is introduced to the system, and it affects the’ dynamic positioning precision of the radar. In this paper, a mathematical model describing the dynamic error is given. Based on this model, a method for testing the dynamic error is developed, which is easy to adopt from the engineering point of view. Also developed here is a new technique to improve the dynamic positioning precision by using a computer to correct the dynamic error. In conclusion, this paper gives the source program for correcting the dynamic error written in ALGOL-60, and the results of running the program on a NOVA machine.2|26|0更新时间：2025-12-08
- 摘要：Kalman filtering can be used for target tracking, both in electronic scan radar systems and in mechnical scan radar systems. In the former systems, it is used to directly initiate beams to move, while in the latter systems, it is used for exact measurement without the problems caused by servo tracking structure. The tracking loop formed by Kalman filtering will have target bias-zero tracked, when working in parallel with the servo-tracking loop. The state estimation of Kalman filtering serves as coordinate output of radar measurement as well as complex control signal for serve systems, so as to realize computer-aided-tracking. The video closing test shows that it" has satisfacfory performance.In order to improve the accuracy and to solve the problems caused by the difference between model designing and actual moving of targets, this paper presents an adaptive method of detecting maneuvering by mean-variance and modifying gain directly. The flying tests of an experimental scan array radar shows that this method has more effective result than those without adaptive constant coefficient tracking systems.2|113|2更新时间：2025-12-08
- 摘要：A new method of compiling and computing the hyperbolic lattice navigation tables is introduced. It is a new double argument navigation table with which the geodesic coordinates can be obtained directly from paired time differences. Its arrangement pattern and contents are completely different from the present LORAN table of USA. The position fixing procedures are simplified. The geodesic coordinate of receiver can be found simply by the operations of addition, subtraction, and multiplication and need not knowing the predicted position of vehicle. The troublesome procedure of drawing also can be avoided. It takes only 1-2 minutes to make a position fixing by using this new table as compared with 3-5 minutes by using USA LORAN table.2|14|0更新时间：2025-12-08
- 摘要：double Y-junction circulator is constructed by applying shunt open-circuited stubs in the center of a stripline simple junction. Its circuit model is established. The performance of its broad-band low VSWR is theoretically analyzed, and the design for a typical case is made. A VSWR≤1.10 and an isolation≥26dB are obtained in the 2.7-3.7 GHz range. The theoretical analysis coincides with experimental results very well.2|84|4更新时间：2025-12-08
- 摘要：This paper gives two kinds of circular polarizer made of several pho to-etched copper strip or strip-grid fiberglass epoxy plates. One is called strip type, the other strip-grid type. The former has good performances at center frequency, the latter has broad-band performance. These two polarizers may be made into a polarized board as a cover set in front of the waveguide horn. Using curves and formulas given in the paper, the design and calculation may be very simple. Experiments have shown that within about 20% of the band-width of the strip type polarizer the axial ratio of circular polarized field is better than 2 dB and VSWR less than 1.1, and that within more than 20% of the band-width of the strip-grid type polarizer the axial ratio of circular polarized field is better than 1dB and VSWR less than 1.1.2|138|7更新时间：2025-12-08
- 摘要：In this paper, the generalized impedance transformation method[1] is used to solve eigenequation and eigenvalue of the fundamental mode in the specific waveguide with various shapes. This method reduces the engineering calculation to solving the general epuation. It’s conciseness is very obvious especially for dealing with complex problems. Several typical examples are computed and experimented. The results of the computation are basically identical with those of references[2,3,4]. The specific waveguides have found many applications in microwave power sources and microwave magnetic devices. There have been a number of methods for analysing and treating this kind of waveguides. But up to now, no concise and general methods is reported for dealing with various shape waveguides. The introduction of unconti nuous capacitances and the change of matrix elements which change with the variation of transverse impedances are considered, and by using the generalized impedances transformation method, the eigenequation which is, to a certain extent, general for various shape waveguides is derived. This method described can meet the requirements for engineering calculation.2|54|4更新时间：2025-12-08
- 摘要：In this paper the electro-parameter of high purity GaAs epitaxial layers and their process conditions are reported. The vapor epitaxial growth is obtained in the Ga-AsCl3-H2 reaction system at high water vapor partial pressure （μ4.1 ×10-6atm） and low deposition temperature （650℃）. The optimum mobility value at 77°K is 21lOOOcm/s.V and its corresponding peak （44.2°K） is 329000cm/s.V. The 77°K mobility values are generally repeated at 120000-200000cm/s.V. And the high pure materials have an outstanding characteristic of low compensative ratio. In this paper, the experimental results are briefly discussed too.2|21|0更新时间：2025-12-08
- 摘要：This paper presents an automatic gain control circuit in which the time constant varies continuously and automatically. Its physical process is first explained, and then its transient state and stable state are analysed. Finally it is pointed out that the system is a generalization of the general automatic gain control circuit in which the time constant is fixed. Not only can the system suppress high level interference pulse and its output dynamic range, but also ensure a sufficiently low countermodulation distortion of useful signal at low level.An additional device is chiefly made up of the automatic gain control system of varying time constant. Connecting the device with the terminal of the short wave receiving equipment EKV-12, Berlin, 1975, it can lower error code rate by and raise signal-noise ratio by 10 dB with respect to the EKV-12.2|87|6更新时间：2025-12-08
- 摘要：<正> 中国科学院上海冶金研究所不久前制备了35.8k位磁泡存储器芯片。芯片采用主次环组织,计93只次环,次环位数为385。次环中位周期为20μm,次环的排列周期为46μm,即存储密度为2×105位/cm2。磁泡的Ni-Fe膜传输图形为不对称山形,磁泡以Ni-Fe厚膜蛇形磁阻检出器扩展检出,图形最小线宽为2μm。2|13|0更新时间：2025-12-08
- 摘要：This paper analyzes the probability of the false-frame sync and the number of the false-frame sync per frame in a digital transmission system. More exact equations for the number of the false-frame sync per frame are derived. It also provides the ideal curves that are different from traditional ones for determining the performance of the frame sync code. On this basis, a new type of the frame synccode-SB code （Super-Barker-Code） is recommended. When used as the frame synccode, its performance is super to Barker-Code.2|179|3更新时间：2025-12-08
- 摘要：The development of a complex electronic system may be divided into several stages. Let λ1 be the failure rate of the system in the i-th stage. In many situations, the reliability of the system increases stage by stage, i. e. λ1>λ2>…> λm. we choose the prior distributions of λ’s to be such that the Bayes confidence interval of A followed from the posterior density function is equivalent to the result of the classical statistics. Let f1 （τ1|λ1） be the conditional probability function, where τ1 is the total life time in the i-th stage, then the posterior density function isthe marginal posterior density function of Am iswhere is, the space formed by is the domain of λj, and is the subspace of 0. The r-confidence interval of λm is（o, λm…）, whereIn classical statistics, we can only use rm to calculate the r-confidence interval for Am, because the statistics r, （i = 1,2, …, m-1） belong to another population. But now we can use the formulas derived in this paper to calculate the r-confidence interval for Am not only by using rm, but also by using τ1, τ2, …, rm-1. The size of the sample of the m-th stage using this method will be smaller than the sample of the m-th stage using the classical statistics.2|128|11更新时间：2025-12-08
- 摘要：This paper presents a new way of using nonlinear network to change frequency for high-frequency power source. It is proved by computer-aided analysis and experimental demonstration that such high-frequency power source is featured by high efficiency, low cost, convenient load matching, easy maintenance, etc., and is very suitable for induction heating. This prototype has already been put into industrial operation. The technical data of the prototype is given at the end of the paper: a rated power of 150 kW, output frequency of 25-63 kHz, electric efficiency of 90.5%, and output frequency modulation characteristic, etc., In the prototype, just by changing load parameters, any needed frequency can be obtained conveniently at 25-63 kHz while keeping the rated power, without changing the internal network parameters and input frequency. This feature does not exist in power sources using other ways to change frequency. Theoretical analysis and the mathematical model are given for such a high step nonlinear network. It is expected that with the aid of the general computing routine of a digital computer, the optimization design of series products can be realized, thus ensuring its wide applications.2|15|1更新时间：2025-12-08
- 摘要：The construction of an Ar-N2 transfer laser pumped by a radial relativistic electron-beam is described. It is the first laser of this type made in our country. Laser emission at wavelengths 3577A and 3805A has been obtained simultaneously. The laser output is 3 mJ. Theenergy extraction volume density is 1J/liter. We study the characteristics of this laser too.2|13|0更新时间：2025-12-08
- 摘要：In order to test noise performance of Josephson junction mixer, a liquid-nitrogen noise source at 8mm band has been made, in this paper, the principle, construction as well as calibration of noise temperature are described. An error analysis is also given. The output equivalent noise temperature （of L-N2 noise source） is estimated as:2|28|0更新时间：2025-12-08
- 摘要：This paper describes an accurate method for measuring the efficiency of low loss reciprocal two-ports network under larger mismatch. The measuring accuracy of the system does not depend strictly on the mismatch of the device to be tested. For example, if the reflection coefficient and the efficiency of the device are 0.1 and 0.99 respectively and the reflection coefficient of the load to the device is 0.1, the mismatch error is only ±2×10-4. The total uncertainty for this case is 0.06%.2|31|2更新时间：2025-12-08
- 摘要：The Monte-Carlo method is suitable to the realization of the computer simulation of radar signal detection. In this paper the procedure of simulation by the computer DJS-6 is briefly introduced and the importance sampling is applied to the simulation of lower false alarm probability of a cell-average detector.2|47|0更新时间：2025-12-08
- 摘要：In this paper, the phase conjugate nature of the nonlinear coupling forward wave has been demonstrated. The experiment agrees with the theoretical results.2|33|1更新时间：2025-12-08
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