摘要:

AbstractA new technique of speech analysis based on a composite sinusoidal model is proposed. In this model, parameters (frequency and intensity of each sinusoid) are determined such that the lower‐order autocorrelation functions of the finite number for the reference signal (a sum of several sinusoidal waves) is equal to those for the observed speech signal. The model is classified into four types: (1) the frequencies of the sinusoids are free; (2) one frequency is fixed to 0; (3) one frequency is fixed to π; and (4) two frequencies are fixed to 0 and π. For all of these, the parameters are solved easily by the basic algebraic method. While the problem is essentially related to the theory of orthogonal polynomials, it is proven that the roots exist if only the autocorrelation function is a positive definite matrix. The efficient algorithm is introduced. Itakura's theory of line spectral representation of linear predictive coefficients can be considered as the conversion theory from the LPC to the composite sinusoidal model. Some experiments of speech analysis are demonstrated. Applications to the speech analysis and synthesis, synthesis by rule, speech recognition, speaker identification, etc., are sugges

ISSN:8756-6621    

DOI:10.1002/ecja.4410640202

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

年代:1981

数据来源: WILEY

摘要:

AbstractA chromatic spatial sinusoidal pattern composed of a complementary color‐pair is displayed on a color‐monitor screen, and, on adding color (saturated Y, M, C and B) to the screen, the color‐difference discrimination threshold for the colored chromatic sinusoidal pattern is determined at low frequency (0.36 cpd) and high‐frequency (3.6 cpd). The direction of the complementary color‐pair, along which the high‐frequency sensitivity decreases most at each color, passes through a point on theu‐axis of the CIEu vchromaticity diagram and almost coincides with the color‐confusion locus of the third color‐abnormal case. On the other hand, the direction of the complimentary color‐pair along which the high‐frequency sensitivity decreases least is almost parallel to theU‐axis. These results indicate that the spatial frequency characteristic of the chromatic channel can be considered to be independent of

ISSN:8756-6621    

DOI:10.1002/ecja.4410640203

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

年代:1981

数据来源: WILEY

摘要:

AbstractThe error‐correcting codes have been used extensively to increase the reliability of digital systems in data communication. However, with increasing error‐correcting capability, the complexity of decoders also increases. At present, only one‐bit and two‐bit error‐correcting codes are used. This paper proposes a decoding algorithm for triple and quadruple error‐correcting BCH codes. In decoding the BCH codes, the error‐locator polynomials must be solved by Chien's algorithm. In his method, however, with increasing code length, the decoder becomes complicated and the efficiency deteriorates. In the method proposed in this paper, the fourth‐or lower‐order equations are reduced to the quadratic equation and, therefore, the efficiency is good. This method is also independent of the code length. Its function and efficiency are confirmed by simulation using microcomputer. The present decoding algorithm enables one to realize an efficient decoder with hardware construct

ISSN:8756-6621    

DOI:10.1002/ecja.4410640204

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

年代:1981

数据来源: WILEY

摘要:

AbstractIC realization of a switched‐capacitor transformer withininteger turn ratios, based on alternating and switching series and parallel‐connections of capacitors is presented. The circuit consists ofncapacitors and 3n+1 MOS FET switches. This circuit is advantageous in that it has monolithic IC capability, DC voltage step‐up and step‐down are possible and non‐grounding can be achieved. It is thus useful for the integration of difficult circuits containing transformers. In this paper theoretical analyses are given for the case of ideal capacitors and switches, and for the case of non‐zero stray capacitance and on‐resistance. The effects of the on‐resistance of switches on the transfer characteristics of the transformer on the operating frequency range, allowable input level, element sensitivity and temperature characteristics are shown both theoretically and experimentally. As an example of applications, the test of a first‐order all‐pass filter is presented. The test used two 1,000pF capacitors and MOS FET switches; voltage step‐up and step‐down in the range from DC to 100 kHz were demonstrated. In this case the maximum allowable input level is about 0.5V and stability is ensured at temper

ISSN:8756-6621    

DOI:10.1002/ecja.4410640205

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

年代:1981

数据来源: WILEY

摘要:

AbstractIn recent years, an interaction between electromagnetic environment and the living body has attracted researchers' attention. The authors have studied the effect of low‐frequency (50, 60 Hz and dc) electric field on the living body and constructed the electric field exposure system. In the conventional exposure system, animals are exposed to electric field between parallel plate electrodes in an insulated cage. However, the electric field inside the cage has not been investigated in detail. In this paper, the electric field intensity and the field uniformity inside the cage are analyzed. Based on the analysis result, a new exposure system is designed. The electric field distribution inside the cage is analyzed by the finite‐difference method. The field uniformity is more than 84%. The measured value agrees with the calculated value. The new system is simple in structure, can readily be constructed and is reliable for a long t

ISSN:8756-6621    

DOI:10.1002/ecja.4410640206

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

年代:1981

数据来源: WILEY

摘要:

AbstractThe propagation path of cyclotron harmonic waves in the ionosphere and magnetosphere was derived by J. Bitoun. However, the propagation path at low altitude has not yet been investigated. This has been due to the complexity in the analysis in which the curvature of the earth's magnetic field must be considered. In this paper, the propagation path is expressed in a simple equation which considers the curvature of the earth's magnetic field. With this expression, the traveling distance varies depending on the magnetic latitude and altitude of the location of the wave exciter. With the assumed electron density distribution, the corresponding regions in the ionosphere and magnetosphere are clarified. Then the propagation path is calculated with two representative points in these regions. When kX0>0, the traveling distance becomes maximum after the reflection point. When kX0<0, the effect of the curvature is large, causing a large variation in the traveling distance.

ISSN:8756-6621    

DOI:10.1002/ecja.4410640207

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

年代:1981

数据来源: WILEY

摘要:

AbstractAn expression for the attenuation loss of submarine coaxial cable systems must provide a precisely calculated attenuation loss at any frequency in the environments of temperatureTand water pressureP. The expression, based on the cable loss characteristics measured at atmospheric pressure on land, must yield an accurate estimate of the cable loss characteristics at the sea bottom.Here, we propose a general expression for the attenuation as a function off,TandP. The expression is based on some material characteristics and sizes, which are the basic parameters defining the transmission characteristics of a submarine coaxial cable. Owing to the introduction of a polynominal representation for the dielectric loss characteristic tan δ which has hitherto not been taken into account, we were able to derive an expression for the attenuation vs. temperature and water‐pressures and to demonstrate explicitly that variations in attenuation caused by temperature and water pressure changes can take the form of polynominal equations inf,TandP. Further, we shall introduce a finite‐order, simple and practical polynominal formula as. an expression for the case when some limitations are allowed on the frequency and on the accuracy of calculating the attenua

ISSN:8756-6621    

DOI:10.1002/ecja.4410640208

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

年代:1981

数据来源: WILEY

摘要:

AbstractThe resonant characteristics of the shielded TM010dielectric rod resonator are analyzed and its design method is proposed. The resonant frequencies and the no‐load Q value are calculated and their dependence on the specific permittivity and dimension ratio is clarified. Then with a constant ratio of the frequencies of the TM010mode to higher modes, the optimum dimension for the maximum no‐load Q value is determined. The temperature characteristics of the resonator are improved by inserting the conductor to both ends of the rod. The effectiveness of the design method is confirmed by the experiment. The resonator advantages are such that higher modes do not appear in the frequency band over more than one octave, and the no‐load Q‐value

ISSN:8756-6621    

DOI:10.1002/ecja.4410640209

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

年代:1981

数据来源: WILEY

摘要:

AbstractThe VHF 2‐channel adaptive antenna system was constructed by means of the output minimization under directional constraint, and its performance was evaluated. In the field experiment, the preservation of the desired signal and elimination of the interference wave were confirmed. The system adopts a hybrid‐type implementation of the analog processing part and digital processing part. The correlation between the input and output is calculated by the analog portion and the remaining computation is made by the digital portion. The time variation of the desired signal and the interference component, the frequency spectra of the output and the antenna directivity were measured in the laboratory. When the desired signal and the interference wave have the common frequency band, the interference wave can be suppressed sufficiently by this system if their incoming directions differ. The signal‐to‐interference ratio was above 30 dB. In the field experiment, we obtaine

ISSN:8756-6621    

DOI:10.1002/ecja.4410640210

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

年代:1981

数据来源: WILEY

摘要:

AbstractFurther integration of the dynamic MOS RAM (MOS(D)RAM) depends on improvements in fabrication and in device and circuit techniques. To attain better operating characteristics and stable operation for large‐scale integration, it is necessary to establish a design approach that combines all of these techniques. This paper describes such an approach. First, the coefficientmdefining the sensitivity, read‐voltage and the operating region of the sense circuit is established and the design guidelines of the sense circuit are then derived. Analysis of the coefficientmshows that variations in device parameters attributable to processing accuracy significantly affect the stability of the large‐scale MOS(D)RAM operation. To obtain a wide operating region for the 64K MOS(D)RAM, the 128 refresh method is shown to be advantageous. Next, based on the design guidelines it is shown experimentally that 64KMOS(D)RAM can be fabricated with wide upper‐ and lower‐operating limits and that the design approach to large‐scale MOS(D)RAM using the fine‐pattern fabrication technique presented here is

ISSN:8756-6621    

DOI:10.1002/ecja.4410640211

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

年代:1981

数据来源: WILEY