By using measured attenuation time-series data over 2 years at 19.5GHz with an integration time of 1 sec, effects of the integration time on attenuation statistics are presented. It is observed that the effect on cumulative distribution of attenuation and the relation between annual and the worst-month cumulative time percentages are not significant for the practical prediction purposes. The effect is significant in attenuation duration statistics.

This paper gives a systematic approach to generate a Markov chain by a discrete-valued auto-regressive equation, which is a a nonlinear auto-regressive equation having a discrete-valued solution. The power spectrum, the correlation function and the transition probability are explicitly obtained in terms of the discrete-valued auto-regressive equation. Some computer results are illustrated in figures.

The regulatory mechanism of protein synthesis on a messenger RNA was analyzed from view point of the optimal control and discussed about availability for artificial production of peptide and protein. The transient movements of a ribozome through a messenger RNA with its production of peptide was based on the theory proposed by Gordon (1968). The optimal state of total process was defined as the state at which the time dependent change of each process of peptide synthesis has been minimized during a given time interval. This biological problem was converted into mathematical one by setting state variables and utilizing the optimal control theory with the help of Hamiltonian function. The first process of transition of a ribozome on a messenger RNA showed the largest change and with progress of state, the magnitude of change of each process decreased and became a simpler pattern. The effect of weighting coefficient relating with individual process was not confined only to its proper process but extended to all other processes. Each process was affected from all other processes. These were manifestations of effective and rational control strategies particularly for regulation of the sequential reaction in peptide synthesis. Such results were originated in the operation of the optimal control. By simulating physiological experimental data, it is possible to predict at what process and at what degree, the synthesis is regulated in order to achieve the optimal synthesis state. By analyzing the optimal synthesis process in combination with physiological experimental data, it would be possible to create artificial peptide and protein.

When used for automotive applications, microcomputers have to meet two requirements more demanding than those for general use. One of these requirements is to respond to external events within a time scale of microseconds; the other is the high quality and high reliability necessary for the severe environmental operating conditions and the ambitious market requirements inherent to automotive applications. These needs especially the latter one have been responded to by further elaboration of each basic technology involved in semiconductor manufacturing. At the same time, various logic parts have been built into the microcomputer. This paper deals with several design approaches to the high quality and high reliability objective. First, testability improvement by the logical separation method focusing on the logic simulation model for generating test vectors, which enables us to reduce the time required for test vector development in half. Next, noise suppression methods to gain electromagnetic compatibility (EMC). Then, simplified memory transistor's analysis to evaluate the V/I-characteristics directly via external pins without opening the model seal, removing the passivation and placing a probe needle on the chip. Finally, increased reliability of on-chip EPROM using a special circuit raising the threshold value by approximately 1(V) compared to EPROM's without such a circuit.

A theoretical and experimental study of a thin card-sized antenna is presented. The method of moment with a wire-grid model is used to analyze this antenna. In order to validate numerical efficiency, measurements using Wheeler method are preformed on this antenna and its wire-grid models. The experimental and theoretical results are in good agreement if the wire conductivity is well chosen. And the noise reduction of measured Wheeler efficiency using least mean square method is also examined.

The invariant imbedding method combined with the time domain wave splitting technique is applied to the inverse problem for the telegraph equation t2u=(1/r)(pu)-btu+qu in a stratified half-space. The zeroth, second and fourth moments of the 3-D fields are used to reduce the three-dimensional problem to a set of one-dimensional problems. The imbedding equations for R0, R2 and R4, respectively the zeroth, second and fourth moments of the reflection operator, are derived. Numerical results for the reconstruction are presented using the reflection data on the surface.

A new superresolution technique is proposed for antenna pattern measurements. Unwanted reflected signals often impinge on the antenna when we measure it outdoors. A time-domain superresolution technique (a MUSIC algorithm) has been proposed to eliminate the unwanted signal for a narrow pass-band antenna. The MUSIC algorithm needs many snapshots to obtain a correlation matrix. This is not preferable for antenna pattern measurements because it takes a long time to obtain the data. In this paper, we propose to reduce a noise component (stochastic quantity) using the FFT and gating techniques before we apply the MUSIC. The new technique needs a few snapshots and saves the measurement time.

The relation between the radiation pattern and the dimension of the conducting box for a portable telephone is illustrated both theoretically and experimentally. The Galerkin-moment method using the Fourier series expansion for the surface current of the conducting box, which has a great advantage of having a high accuracy, is employed to obtain the radiation pattern. As an example of antennas, a quarter-wavelength monopole antenna having a sinusoidal current distribution is used. As a result, it is pointed out that the radiation pattern of a monopole antenna mounted on the box tends to tilt in a lower direction both in theory and in experiment as well. The relation between the radiation pattern and the location of the monopole antenna is also described. An asymmetrical, or distorted pattern is observed when the monopole antenna moves away from the center of the top plane.

This letter proposes a microstrip band elimination filter having an optically controlled small gap on a resonant section for the shift of the eliminated frequency range using the semiconductor plasma. The basic characteristics of this filter are analized theoretically utilizing the (FD)2TD method.

We extend the concept "optical instanton" to arbitrary dielectric media. For these general cases the exact analytical approach is no longer available. We derive an approximate analytical solution that would be valid in the vicinity of the light cone. A comparison is made between the analytical and the numerical solutions.

A rectenna element applicable to Stratosphere Radio Relay System was proposed and a fundamental microwave power transmission experiment was carried out at 2.45GHz using a rectenna array manufactured based on the proposal. The rectenna element consists of a circular microstrip patch and a rectifying circuit of novel balanced-type design. The circuit allows to mount a rectifier and circuit components just on one side of a substrate without through holes, and hence it must be easy to manufacture a rectenna even having a large aperture. It was verified by a preliminary experiment that the rectifying circuit can provide more than 1 W of DC output power using 8 Shottky diodes as a rectifier with microwave-DC conversion efficiency of 67%. Then, DC output power of 4W was obtained from the 4-element rectenna array in the microwave power transmission experiment carried out in a radio anechoic chamber. The data showed a feasibility of practical application of the microwave power transmission technique.

A 10 GHz MMIC predistortion linearizer fabricated on a single chip is demonstrated for the first time. It employs less hybrid circuits compard with conventional devices, and is suitable for miniaturization. The total chip size of the fabricated MMIC is about 3.5 mm3.0 mm. The distortion reduction effect is examined using this linearizer. The improvement in IM3 is more than 15 dB between 10.45 GHz and 10.70 GHz, and more than 8 dB between 10.05 GHz and 10.90 GHz.

An omnidirectional microstrip antenna using a parasitic cylinder is presented. A rectangular patch is formed on a dielectric substrate and it's completely covered with an aluminum cylinder which is somewhat shorter than a half of free space wavelength. Under such configuration the aluminum cylinder works as a parasitic element. This antenna can provides uniform omnidirectional radiation patterns and a broad frequency bandwidth. In this paper an experimental method for designing such an element is described. Measured input impedance characteristics, current distribution around the surface of the cylinder and patterns are also shown. By properly adjusting the coupling intensity between the patch and the parasitic cylinder a broad bandwidth antenna element can be realized. Some methods to adjust the coupling intensity are shown. A wide bandwidth element up to 14% for VSWR1.5 is obtained. Arranging many patches lengthways on a substrate and placing metallic cylinders around each patches, we can realize a high-gain and broad bandwidth collinear antenna.

This letter shows that VEPs can be easily measured by using color cards as the color stimulus, and that the responses evoked by a difference in chroma could be described largely by the value of the first principal component in principal component analysis.

The potential distribution around a linear array of donor atoms in a semiconductor crystal is calculated, approximating the linear array by a continuous line charge. Two methods are used for the analysis. One is the self-consistent calculation of Poisson's equation and the effective mass Schrödinger's equation, and the other is the Thomas-Fermi approximation. Results of both methods agree very well, and it is shown that it is possible to form a potential distribution as fine as the electron wavelength by appropriate arrangement of the impurity atoms. Arrays of impurity atoms therefore can act as buiding elements for future electron wave devices.

High variability of object features and bad class separation of objects are the main causes for the difficulties encountered during the interpretation of ground-level natural scenes. For coping with these two problems we propose a method which extracts those regions that can be segmented and immediately recognized with sufficient reliability (core regions) in the first stage, and later try to extend these core regions up to their real object boundaries. The extraction of reliable core regions is generally difficult to achieve. Instead of using fixed sets of features and fixed parameter settings, our method employs multiple local features (including textural features) and multiple parameter settings. Not all available features may yield useful core regions, but those core regions that are extracted from these multiple features make a cntributio to the reliability of the objects they represent. The extraction mechanism computes multiple segmentations of the same object from these multiple features and parameter settings, because it is not possible to extract such regions uniquely. Then those regions are extracted which satisfy the constraints given by knowledge about the objects (shape, location, orientation, spatial relationships). Several spatially overlapping regions are combined. Combined regions obtained for several features are integrated to form core regions for the given object calss.

We analyze the nonlinear dynamics of PLL from the "complex" singularity structure by introducing the complex time. The most important results which we have obtained in this work are as follow: (1) From the psi-series expansion of the solution, the local behavior in the neighbourhood of a movable singularity is mapped onto an integrable differential equation: the Ricatti equation. (2) From the movable pole of the Ricatti equation, a set of infinitly clustered singularities about a movable singularity is shown to exist for the equation of PLL by the multivalued mapping. The above results are interesting because the clustering and/or the fractal distribution of singularities is known to be a characteristic feature of the non-integrability or chaos. By using the method in this letter, we can present a circumstantial evidence for chaotic dynamics without assuming any small parameters in the equation of PLL.

It was more than 10 years ago that the first map navigation system, as an example of invehicle information system, has appeared in the market in Japan. Today's navigation system has been improved to the level that the latest system has 10 micro-processors, 7 MBytes of memories, and 4 GBytes of external data storage for map database. From the viewpoint of the automobile driver, there are still some problems with the system. Major problems in general are a lack of traffic information, better human interface, and a need for cost-reduction. The introduction of application specific ICs (ASICs) is expected to make systems smaller, costless, and give higher speed response. Today's in-vehicle information systems are reviewed function by function to discover what functions need to be implemented into ASICs for future systems, what ASICs will be required, and what technology has to be developed. It is concluded that more integration technology is expected including high parformance CPUs, large capacity memories, interface circuits, and some analog circuits such as DA converter. To develop this technology, some, major problems such as power consumption, number of input/output signals, as well as design aid and process technology are pointed out.

Electronics and automobiles were bound together by the introduction of emission regulations in the 1970's. The rapid progress of control technology and semiconductors that typify microcomputers has brought still closer relations between them. Without electronics, it would be impossible to realize features such as pursuit of comfort and environmental and safety measures which should be added to the automobile's fundamental features. In looking ahead to the future, the role of electronics in achieving electric automobiles and the ultimate goal of "automatic driving" is ever-increasing. Everyone knows that automobiles have become indispensable in our lives. In the future, the role of electronics will become increasingly important in order to evolve automobiles even further to allow harmonization with society.