摘要:

AbstractWhen a signal from a moving source is received by a phase‐locked loop (PLL), the input‐signal frequency of the PLL often changes in a ramp‐function state with a constant‐frequency offset. In such a case, a perfect third‐order PLL is needed to track the signal without steady‐state phase error. The conventional perfect‐integration third‐order PLL has a serious problem of being unstable for small‐amplitude inputs, and thus it cannot be used in practice in a low SNR environment.This paper proposes three types of stable perfect third‐order digital PLL's (M‐DPLL) which are independent of the input‐signal amplitude. This M‐DPLL realizes the perfect third‐order behavior by combining three first‐order DPLLs using a digital signal processing technique. The excellent characteristics of this M‐DPLL are confirmed by theoretical a

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700801

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

年代:1987

数据来源: WILEY

摘要:

AbstractA new lift‐off process for a microscopic pattern formation in a Josephson junction integrated circuit has been developed using high resolution deep‐UV photoresist (MRS). The single‐layer photomask with an overhang structure suitable for a lift‐off process was fabricated using a deep UV contact exposure and development process. Using a low temperature (70°C) lift‐off process with MRS, it was possible to form a Pb‐alloy pattern with the line width and line spacing of 0.8 μm and obtain the 1.5 μm □ contact window through the SiO film.With the new lift‐off process using MRS, experimental Pb‐alloy type Josephson junction integrated circuit chips, which were formed by 1.0 μm design rule, were fabricated. As a result, it was confirmed that this process was suitable for forming patterns with dimensions less than 1 μm. However, the remains of MRS in the lower electrode surface in the window caused the scattering of the junction currents. The remains could then be removed with a cleaning treatment of the lower electrode using ozone (O3) generated by a UV with

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700802

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

年代:1987

数据来源: WILEY

摘要:

AbstractCommunication lines damaged during a disaster must be restored quickly since this seriously affects society. This paper examines the applications of optical cables to restore communication lines quickly in a large‐scale disaster area where mechanical tools cannot be used. The paper also offers the conditions required for the structure design of the cable. Based on these examinations, an optical cable for emergency use was developed which contains four optical fibers, and weighs about 25 kg (including its reel), and can be carried by one man. The unit piece of the cable is 1 km; the numbers of pieces can be connected as required. Disaster cases where damaged cable sections are scattered on interoffice lines were examined, and the number of the sections which can be restored was estimate

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700803

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

年代:1987

数据来源: WILEY

摘要:

AbstractAn automatic wafer transportation system has been developed that is suitable for the LSI fabrication line. Design objectives have been to achieve a flexible wafer routing and flexible line construction ensuring a high degree of cleanliness. The system consists of a computer‐controlled carriage system carrying wafer cassettes on a ceiling track, and standardized interface mechanisms installed on each equipment. This paper describes technical factors involved in the realization of flexible lines, and considers also fundamental track arrangement, carriage characteristics, a wafer‐routing control method, and low dust mechani

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700804

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

年代:1987

数据来源: WILEY

摘要:

AbstractTwo nonuniform coaxial transmission lines have been fabricated in which the primary parameters of the line vary parabol‐ically and cosinusoidally. The characteristic impedances and the matched loads have been measured and the application to a broadband impedance transformer has been studied. The results show that the characteristic impedance distribution of the nonuniform coaxial transmission line does not coincide with the nominal characteristic impedanceZ0(x) but agrees with the solutionZp+(x) of the differential equation for the impedance derived from the telegrapher's equation. It is also demonstrated experimentally that the standing wave in the transmission line vanishes completely ifZp+(l) is connected at the terminal (x=l) and, hence, this value provides an effective matched load. It is found that under this matched condition both of the nonuniform coaxial transmission line eleoents operate as an impedance transformer over an extremely wide frequency range exceeding 0.5 GH

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700805

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

年代:1987

数据来源: WILEY

摘要:

AbstractTo take advantage of the high resistivity and small TCR in amorphous alloys, an Al‐Nb amorphous alloy thin film was prepared by dc sputtering. The thermal aging stability of the film was investigated by the heat treatment in the atmosphere. The film surface was characterized by AEC and XPS analyses. As a result of characterization, it was found that the segregated Al atoms to surface were oxidized preferentially and that a protective oxide film was formed on the surface. The oxidized film did not grow by the heat treatment at 300°C but the structure of the alloy film prepared showed relaxation. The increase in ρ and TCR due to the structural relaxation was discussed in accordance with the electric condition mechanism of liquid alloy. Moreover, nitrogen doping into the film was attempted in order to control the structural relaxat

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700806

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

年代:1987

数据来源: WILEY

摘要:

AbstractThis paper presents a realization of the membership functions (S, Z, ir and U functions) which serve as the input units of the fuzzy logical system, using the bounded difference of the fuzzy logic. The bounded‐difference circuit is constructed by the current mode using the current mirror based on the bipolar transistor array. The circuit for each membership function is realized and the modification of the circuit to other functions is discussed. The multifunction membership function (calledNfunction) is proposed anew, which can realize the four forementioned membership functions flexibly by adjusting the parameters. The circuit forNfunction is constructed in the same way as the four preceding functions. The optimum circuit construction is presented based on theory and experiment. It is also shown that the membership circuit can be simplified usingNandP‐channel FET arrays. An FET circuit is presented which can eliminate the essential error in the current mirror composed of bipolar transist

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700807

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

年代:1987

数据来源: WILEY

摘要:

AbstractThe optimum design of a vertical power MOSFET with thick drain oxide is described, taking into account such dc characteristics as the on‐resistance and breakdown voltage.Introducing the empirical ideality of the edge‐termination which determines the breakdown voltage of the device, the optimum doping density and thickness of the epitaxial layer have been determined to minimize the on‐resistance.Using two‐dimensional simulation to evaluate the optimum design of the device, the thickness of the drain oxide and the relationship between the layout pitch and the product of on‐resistance and active area have been determined. As a result, the following conclusions have been obtained.1) Based on the ideality for the edge‐termination, the optimum combination between the thickness and the doping density of the epitaxial layer can be determined.2) The optimum layout pitch depends on the decrease in the electron concentration in the accumulation layer at the drain surface and the parasitic JEET effect.3) The optimum layout pitch decreases as the thickness of the drain oxide increases.Finally, the design of a vertical MOSFET with a breakdown voltage of 500 V will b

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700808

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

年代:1987

数据来源: WILEY

摘要:

AbstractTo increase the bandwidth of the traveling‐wave‐type light modulator, it is necessary to decrease the difference between the velocity of the modulation wave and that of light. The velocity mismatch was improved by incorporating a buffer material with low dielectric constant between the electrodes and substrate so that the modulation efficiency does not deteriorate and the capacitance between the electrodes is minimized. Considering not only the bandwidth but also the ratio between the driving power and the bandwidth (P/Δf), three types of structures have been proposed.For the theoretical analysis, the modulation wave traveling through the electrodes was assumed to be a TEM wave and the model of the two‐dimensional static electric field was adopted. However, since the structure was complicated, a numerical calculation was needed in which the boundary element method was used. The structure with leastP/Δfratio was chosen by using the result of the calculation. As a result of further calculation on the chosen structure with the various thickness of the buffer layer, it was found that the bandwidth is improved drastically and the ratio ofP/Δfbecomes small by increasing the width of the buff

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700809

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

年代:1987

数据来源: WILEY

摘要:

AbstractSince the miniature and high‐density electronic apparatus was developed, the miniaturization of electronic components has been in high demand. The reed switch is not an exception. The reed switches for the P.C.B. mounted miniature relays and the surface mounted miniature relays have also been in high demand. The reed switch which has been used for communication is rather large (46 mm in its entire length and composed of a 28‐mm‐long glass tube). However, the design of the switch itself is almost ideal.This paper discusses the miniaturization limit of the reed switch with respect to the mechanical and magnetic properties. Assuming that the breakdown voltage, the contact rating and the carry current decrease, it was found that the ultraminiature reed switch with glass inner length of 3.6 mm and glass inner diameter of 0.8 mm can be mass‐produced by the existing processing tec

ISSN:8756-663X    

DOI:10.1002/ecjb.4420700810

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

年代:1987

数据来源: WILEY