Abstract:In this paper are presented the considerations of overall plan of the LFM digital pulse compression radars，and their parameter selection realized in FFT，Which employ the quasi-block-floating point and fixed-point normalized algorithm. These parameters contain the quantized form in FFT computation，word lengths of the A/D converter，the twiddle factor and the butterf1y of the FFT，and so on. Some calculated data and curves are presented by simulated computation via computer，these data can be useful to engineers and designers.

Abstract:Using the radio altimeter for altitude measurement，some departments have put forward two quality requirements for the altimeter: ① to reduce the flickering movement of the altimeter pointer during the flight. ② to replace the upright beavertail antenna of aircraft altimeter with a conformal or low-profile antenna so as to improve the aerodynamic characteristics of high speed aircraft and make it less liable to damage on the ground. Based on the above-mentioned requirements，We make preliminary theoretical and experimental investigafions about the rectangular microstrip antennas for aircraft altimeter. The main results are presented in this paper. Test f1ights have shown that the pointer f1icker of altimeter is distinctly reduced during level f1ights.

Abstract:On the basis of the displayed joint's row-column information stored in the data structure，this paper present an algorithm for the regeneration or translation or scaling-up of the displaying circuit graph and another for the searching and correcting of the record relevant to an object hit by the light pen.

Abstract:This paper discussed the general form of the parametric representations of the cone Curve，and also discussed problem to graph the Cone curve by computer in accordance with these parametric representations. Morcover，this paper still more discussed the normalized method of the three-dimensional sub-graphics data and problem of the coordinates transform during the calling of these sub-graphics.

Abstract:How to reduce the effect of the glitches in high speed D/A converter，it is very important. In this paper are discussed following problems: the produce of glitches，the nature of glitches，the effect of glitches，how to reduce it，and so on.

Abstract:This paper describes the design，fabrication and experiments of the 5and 7-element Tchebyscheff MIC filters. Exeperimental results show that the pass-band attenuation a1most doesn't increase as n is increased. It is a1so shown that the accuracy of both the permittivity of the substrate and the strip 1ength bas important effect in calcu1ating the pass-band shift. Finally，a simple formu1a for calcu1ating this effect is given.

Abstract:We developed a transistor mixer with broadband(100～300MHz). It has not only a mixing gain characteristic of transistor mixer，but also a linear dynamic range approximato to that of the diode. Therefore，it is better solved that the contradiction between the mixing gain and the 1inear dynamic range. However，it is often difficult to explain these characteristics by "The Mixing Transconductance Theory". To overcome these difficueties we try to use "The Mixing Admittance-Linear Gain" Model to expllain these ones so that we easily analyse the testing curve and data of transistor mixers，and proved fundamental agreement of both the model analysis and the practice test.

Abstract:In this paper，the connection between the attenuation characteristics of Chebyshev impedance-transforming network and Chebyshev low-pass fi1ter is estab1ished by selecting an appropriate transforming function. In this way，on the basis of network functions of low-pass fi1ter the calculating formula of element values of impedance-transforming network can be derived by means of network synthesis. Application of these formulas to design impedance-transforming network and application of the correspondent table of element values to do so are mutual1y complementary，Final1y，through an example the method of using the derived formula to calculate network element values is illustrated.

Abstract:In this paper the table to fast determine the limit of convolution is proposed，the feature of the table is analyzed，the method of formation of the table and the steps of solution of convolution by use of the table are discribed. For solution of convolution the method proposed here is much faster and much more convenient than the c1assíc graphical method. On the basis of the table the effective measure to avoid the mistakes in solution of convolution is proposed.

Abstract:This paper introduces the solution of high order algebraic equations by using the root locus method. The main idea of this paper is to reduce the order of the equation by first finding some roots through using the iterative process which starts from the corresponding open-loop poles and then continues along the root locus. This method imposes no restraint upon the characteristics of the equations to be solved and needs no special treatment with equal and complex roots. SO this method is a comparatively simple and practical one.