摘要:

AbstractNumerizing and describing various sensations are important in the discussion of human information processings as well as in the construction of an information processing system, simulating human recognition and behavior. This paper considers the psychophysical function when the stimulus is multidimensional and the corresponding sensation is one‐dimensional. We define a state space spun by several physical continua and a psychological continuum, which is regarded as an n‐dimensional Riemannian space. the psychophysical function is defined as a certain geometrical invariant in this space. A metric is introduced into this state space based on the threshold of discrimination, and functions are derived which are permissible in this case as psychophysical functions. As an application of this formulation a problem is considered to establish a correspondence between the luminance and the brightness of the colored light. It is shown that when Weber's law and Ekman's law apply to the threshold of discrimination, Stiles' law and Abney's law can be derived as the permissible psychophysical functi

ISSN:8756-6621    

DOI:10.1002/ecja.4400660102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

Abstractϵ‐separating nonlinear digital filters were proposed previously for the removal of low amplitude high frequency noise from a signal containing impulsive components. This paper performs statistical analysis relative to the input‐output characteristics of such ϵ‐filters. the analysis is performed for input which is a composite of a dc level or a pulse waveform plus white gaussian noise. Based on the results of the analysis the selection method for the proper ϵ‐parameter is described. Next the analysis is conducted relative to the input signal with a gradual trend (slope). It is shown that the trend (slope) of the input degrades the performance of the ϵ‐filter. Finally, trend‐adaptive ϵ‐filter is proposed to overcome the shortcomings of the basic ϵ‐filter. the statistical analysis is performed for the trend adaptive ϵ‐filter; the performance of this adaptive fil

ISSN:8756-6621    

DOI:10.1002/ecja.4400660103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThe problem of determining the class of passive nonlinear networks with the C1internal energy function proposed by Wyatt, Chua et al., is closely related to the passive realization of nonlinear networks. This paper considers the positive‐real lemma which plays a fundamental role in the passive realization of linear networks. Here, the lemma is extended to general nonlinear networks using the property of solution in the optimal control problem. the results obtained provide an answer to the problem proposed by Wyatt, Chua et al. the positive‐real lemma for the linear case can easily be derived as a special case of the general nonlinear case. the realization problem for the nonlinear n‐port is formulated, and a fundamental property for the passive realization is shown as an extension of the linear

ISSN:8756-6621    

DOI:10.1002/ecja.4400660104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThis paper proposes group‐delay response approximation method based on the ARMA filter, an extension of digital filter approximation by statistical design. Since the denominator and numerator coefficient sequences are in opposite order in recursive group‐delay filters, obtaining either coefficient sequence leads to the other. the approximation described here replaces group‐delay response with the magnitude‐squared response via the complex cepstrum. It is then approximated by an auto‐regressive (AR) filter to obtain the denominator coefficient sequence by linear prediction; reversing this sequence gives the numerator coefficient sequence. A design procedure using the FFT and Levinson‐Durbin algorithm gives a solution much faster than the previous method of solution by means of iterated calculations, in addition to which it is easy to assure that the approximation is stable. A coefficient series allowing realization of a low‐coefficient‐sensitivity recursive structure is directly obtained in the design procedure. Examples of group‐delay equalization and results of radar signal simulation are presented as applications of the approximation method. Finally, some additional problems are considered in connection with the difficulty of obtaining a high‐order approximation with large g

ISSN:8756-6621    

DOI:10.1002/ecja.4400660105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractAs a method of analysis for the general linear lumped circuit including active elements, this paper proposes a new method called the primal dual analysis, in which the backward parts of the cut‐set and tieset analysis are applied in two steps. the problem to determine the minimum number of independent variables for the analysis is formulated from the graph‐theoretic viewpoint. the essential difference between the proposed method and the traditional methods is described from the viewpoint of minimizing the required set of variables. In the case of passive circuits, the problem of determining the minimum independent variables in the primal dual analysis is seen to be reduced to the problem of determining the central tree of the graph. This problem is known to be difficult to solve. In the latter part of this paper, some results for this problem, obtained by the authors up to present, are descri

ISSN:8756-6621    

DOI:10.1002/ecja.4400660106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractAlthough the continuous phase FSK (CPFSK) scheme has been used for narrow‐band data transmission, its error rate performance is rather poor. This paper describes a coding method for improving the error rate performance of the narrow‐band CPFSK scheme with modulation indices of 1/3 and 1/4. the proposed method examines the structure of the signal space for the given modulation scheme and avoids using the signal metric of small value in the coding. Hence, the objective of this method is not error correction, but maximization of the minimum signal metric. the application of this method in narrow‐band CPFSK system yields better performance than the MSK scheme in terms of both bandwidth and error

ISSN:8756-6621    

DOI:10.1002/ecja.4400660107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractA balanced wideband antenna based on the self‐complementary principle is known as a log‐periodic antenna. Another type of self‐complementary antenna, the unbalanced type, has not been extensively studied, even though it is useful in many areas, including mobile communication. This paper describes an unbalanced wideband antenna with an extremely simple structure based on the principle of the three‐dimensional self‐complementary antenna. A method for deriving a unidirectional and constant‐impedance antenna from a three‐dimensional self‐complementary antenna having several symmetrical radiation lobes is proposed, and a theoretical and experimental analysis of the radiation characteristics of a monopole‐slot pair with a finite ground plane is given. It is shown that the radiation characteristics remain almost unchanged when the ground plane is larger than one wavelength in four directions from the center of the antenna pair. It is also shown that the gain in the maximum radiation direction of an element pair is much higher on a semi‐infinite ground plane than on an infinite ground plane. A wide‐band antenna consisting of element‐pairs spaced at equal intervals and with a length taper is described. the antenna exhibits a substantial array effect on the gain. the gain is higher than that of a monopole‐notch array an

ISSN:8756-6621    

DOI:10.1002/ecja.4400660108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractSpread spectrum multiple access (SSMA) is a communication system where narrow‐band information spectrum is spread uniformly over communication bandwidth and plural communication parties share the same frequency band at the same time. In frequency hopping SSMA (or FH‐SSMA), PN signals for spectrum spreading of information signal are generated by a frequency synthesizer. Conventional frequency synthesizers cannot generate PN signals which have the same frequency and phase in the corresponding timeslot at the transmitter and receiver sides independently. For this reason, coherent detection is impossible. Although many frequency synthesizers using SAW filter have been proposed for the realization of coherent communication in a frequency hopping system, there are some problems, including errors in synthesized frequency and phase uncontrollability. This paper presents a new frequency synthesizer to realize coherent communication in FH

ISSN:8756-6621    

DOI:10.1002/ecja.4400660109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThe design principle and construction of an offset bifocal reflector are discussed and some test results are presented. the reflector surface is designed in a three‐dimensional configuration, and four typical bifocal reflector antennas characterized by the vertical and horizontal cross sections of the subreflector are derived. Mapping of the coordinate system set up on the horn feeder is accomplished with a geometrical optics technique, and it is found that an antenna with low distortion cross‐polarization degradation attributable to asymmetry is possible.A 1.3 m bifocal reflector antenna at 14/11 GHz with a beam separation of 9° was designed and fabricated, and its radiation properties were measured with offset feeding, which is useful in constructing a multibeam antenna. the radiation properties within this beam separation angle are equivalent to those of a single pencil‐beam antenna such as the Cassegrainian; the cross‐polarization level is less than ‐30 dB in the

ISSN:8756-6621    

DOI:10.1002/ecja.4400660110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThis paper discusses characteristics of detour routes in store‐and‐forward switching networks for the traffic route assignments one of which is obtained by the optimum route assignment theorem and the other the equal delay principle when message length is generally distributed. the optimum route assignment theorem gives necessary and sufficient conditions for the route assignment to have minimum average message or packet delay‐time over a whole network. the equal‐delay‐principle, which is widely employed in traffic control, can be considered as a theoretical base for determination of an adaptive route using estimated delay‐time. Both traffic assignments obtained by the optimum route assignment and equal delay principle use detour routes to reduce the delay caused by increase of traffic rate. This paper shows that regardless of line capacities and message (or packet) length distribution, the case of the optimum route assignment employs detour route at the smaller traffic rate than equal delay principle. Furthermore, this paper chooses one‐stage parallel route model to show how line capacities and coefficients of variation of message length influences usage of detour routes for thes

ISSN:8756-6621    

DOI:10.1002/ecja.4400660111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY