最新刊期
卷 ， 期 4 ， 1988
- 摘要：This paper describes a monolithic per-channel PCM Codec for transmission and switching applications. The device is implemented in a two-level polysilicon E/D NMOS technology with active area of 13.28mm2. The architecture of the chip allows variable time-slot applications. Measured transmission characteristics show a satisfactory result.2|68|0更新时间：2025-12-08
- 摘要：A terse and efficient implement of global optimization in FORTRAN Compiler is described on base of 151 FORTRAN.2|34|1更新时间：2025-12-08
- 摘要：A model for the extended relational database system, which is used for the relational image database management system IMDAT, and its implementation are described. The concepts of logic value and physical value of data are used in this model. Owing to the extended domain operation and process managing method of such model, the IMDAT system is not only capable of managing ordinary characters and numbers as conventional relational database system, but also can manage image data and vectors coded by different coding methods, thereby effecting the similarity retrieval.2|12|0更新时间：2025-12-08
- 摘要：<正> 由天津大学电子工程系和原电子部三所共同研制的《黑白静止图像传输时问压缩技术设备》,5月11日在天津通过部级鉴定。 静止图像传输设备,是一种利用电话信道作传输媒介的数字电视设备,应用十分广泛。但由于它传输时间长,在一定程度上又限制了它的应用场合。该项技术是在发送端将图像数据减少一米,根据频谱分析原理,采用隔点抽样,两行合并成一行传输。这样做既确保了信号频谱在模拟电话信道中不展宽频带,,又能在接2|10|0更新时间：2025-12-08
- 摘要：In this paper, the random characteristics of maximum multipath excess delay, or the propagation time difference between the longest and the shortest path waves in land mobile communication is discussed. Its distribution density is theoretically derived. The effects of communication environment and of both multipath number and reflection or scatter number are taken into account.2|45|5更新时间：2025-12-08
- 摘要：Numerical solution to the concentration dependent diffusion equation has been developed to study the redistribution of two-dimensional implanted profile in silicon below an ion-etched and a chemically-etched mask edges after thermal treatments. The implanted profile can either be a Gaussian or Pearson Ⅳ distribution. Results show that the lateral extension of boron ions is mainly determined by the initial conditions for a non-ideal masking, it can be as twice wide as that of the vertical direction, however, movement of lateral junction depth after a thermal treatment at a temperature lower than 1200℃ for less than 40sec is insignificant, therefore, the lateral junction will remain unchanged for a typical RTA process for the boron implanted sample. However, in the vertical direction, the junction depth will increase about 5% for 30 seconds diffusion at a temperature only 1100℃.2|16|0更新时间：2025-12-08
- 摘要：A high speed computer sampling system, several processing methods of deep level transient signal, such as the sine weight function method, etc., and past-treating methods of the DLTS spectrum have been established in this paper. Machine language software havs been programmed to realize the methods on the sampling system. Using the system to measure the gold acceptor level in silicon, the result obtained agrees with the data reported in the other literature.2|34|0更新时间：2025-12-08
- 摘要：In this paper, the three-dimensional Walsh sequence spectrum of digital signals of stereo image is analyzed. It is pointed out that the digital signals of stereo image can be compressed to 1/4 of the original data by stereo cross-sampling because the 3-D sequence spectrum of digital signals of stereo image concentrates on the part of 3-D low sequence. The remained and compressed 3/4 signals can be reconstructed with a 3-D lowpass overlapping digital filter In this paper the design of the 3-D lowpass overlapping sequency digital filter is described in detail and a 7×7×7 interpolated mask is also given as a example.2|29|12更新时间：2025-12-08
- 摘要：We describe an exact quadrupole field with square cross-section in which the boundary potential varies linearly with position. Electron optical experiments show that the proposed structure is correct and practicable. Specifications of typical lenses are given in the paper.2|68|1更新时间：2025-12-08
- 摘要：The simplest construction of the equivalent network of linear n-terminal network is discussed and a equivalent network theorem of the linear n-terminal network is proved in this paper. The thevevin-norton’s theorem of two-terminal network is a particular case of the n-terminal network theorem which is given in this paper.4|55|5更新时间：2025-12-08
- 摘要：A model for high-precision analysis of the dielectric resonator feedback GaAs FET oscillator is given. Relations between the FET’s S-parameters and the feedback network parameters under oscillation condition, the oscillation frequency and frequency stability agains. temperature are derived. Two kinds of X-band DRO’s are developed. Both of them achieve high frequency stability over wide temperature range.2|26|3更新时间：2025-12-08
- 摘要：The general principle of the solution of the resonant frequencies of the dielectric resonator is discussed based on BEM. By means of discretization, the boundary integral equations for electromagnetic field are reduced to a generalized eigenvalue equation with the eigenvalues being the resonant frequencies. The method is applicable to an arbitrarily-shaped dielectric resonator. Some numerical results are given to demonstrate the validity of the method.2|67|2更新时间：2025-12-08
- 摘要：A general technique for analyzing junction problems in wire antennas and scatterers is presented. This technique is applicable to analyze junction of wires with different radii, arbitrary shape and number. The results of analyzing and computing some examples by using this method are in good conformity with the given results.2|31|1更新时间：2025-12-08
- 摘要：The random vibration method for the analysis of large parabolic antenna structure response to wind load is proposed in this paper. The power spactral density fonction of wind load and response function matrix of muli-degree-of-freedom system are derived. The unified calculating formulas are given, with which both the static deflections and dynamic re- sponses of structure can be gained simultaneously. A corresponding computer program is designed and an engineering calculation is given.2|96|2更新时间：2025-12-08
- 摘要：In this paper, the moment method, which is capable of being used to solve the problem of combination of a waveguide with a stratified dielectric loaded rectangular cavity, is used to calculate the distribution of microwave fields in the load of a stratified-Ioaded box-type microwave heater, excited by a waveguide, the fields and the input voltage standing wave ratio on the surface of the excited aperture. Optimization of some parameters such as the location and the orientation of the excited aperture is performed in accordance with the requirements of improving the heating uniformity for the load.2|142|8更新时间：2025-12-08
- 摘要：A new method-line segment solution is presented to treat broadband doublematching. The real part of input impedance of matching network is represented approximately by a number of straight line segments on logarithm coordinate, so that it greatly simplifies the calculation of phase function and reduces the degree of nonlinearity of transduce power gain. Finally, an example is presented to show the application in the design of broadband double matching network.2|23|0更新时间：2025-12-08
- 摘要：In the paper some basic concepts involved in software reusability are introduced and the history of the research work is recalled. Several research topics and their essential problems in the field are analysed. Also, the concept of reusable software engineering. some techniques and mathodologies are described briefly.2|70|8更新时间：2025-12-08
- 摘要：An overview of the development and prospects of the optical fiber communications is described. At first, the progress of telecommunications in general and the early inver-tion of optical communication are briefly mentioned. Then, the rapid development of optical fiber communications during the past 10 years, its advantageous features, as wells as the applications and prospects are described in greater detail. It is hoped that the paper will help the readers to have a complete view on the new optical fiber communication technology and its important role in the field of modern telecommunications.2|249|3更新时间：2025-12-08
- 摘要：In this paper the dispersion characteristics of shielded millimeterwave transmission lines are analyzed with the method of lines. The computed results of Ka band finline and suspended microstripline are in good agreement with those given in other literatures.3|35|0更新时间：2025-12-08
- 摘要：: Rapid thermal annealing （RTA） of Si+-implanted undoped SI-GaAs has been studied by using the annealing system adoped a halogen lamp heater. Good electrical properties in activated layers have been achieved. GaAs MESFETs with 0.5w output power and associated gain of 3.5 dB at 6GHz are obtained by this method.2|18|1更新时间：2025-12-08
- 摘要：In this paper the actual structure and the principle of design of a varactor tunned Gunn o-scillator in X-band is presented. The freguency-temperature coefficient of 0.01-2ppm/℃over the temperature range from -40 to 60℃ has been obtained by using a set of new methods for improving the frequency-temperature performance of the oscillator.2|28|4更新时间：2025-12-08
- 摘要：Some new types of Public Key Cryptosystem are presented. The security of the systems rests in part on the difficulty of foctoring the published divisor, large number m or polynomial over fields Q. Main results are given in Theorem 1-3.2|79|4更新时间：2025-12-08
- 摘要：In this paper a concept of non-screen fault exciting source is presented on the basis of reference [1]. The space structure of the source is studied in detail. When the exciting source is applied to a k-fault-network, it can be ensured that each of faults is not screened. Therefore, the parameters of all faults can be evaluated by exciting faultnetwork only once.2|15|0更新时间：2025-12-08
- 摘要：A map synthesis of ternary functions based upon Reed-Muller expansion is discussed by the ternary bj coefficient map.2|20|3更新时间：2025-12-08
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