bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymptotic solutions for the two‐dimensional diffracted field
Authors: Hongo Kohei , Nakajima Eiji 
Published: July 2007

AbstractA simple formula is derived to estimate the asymptotic field diffracted by an infinitely long cylindrical object with an arbitrary cross section when an arbitrary cylindrical wave with directivity is incident. In the analysis, the problem of diffraction of a cylindrical wave by an infinitely long slit is formulated by means of the Kobayashi‐Nomura method, and an asymptotic series solution is derived with respect to the distances between the source and the scatterer and between the scatterer and the observation point. The solution is given in the form of a diffraction pattern function for the plane wave incidence and its derivative. The method is applicable to any diffraction (or scattering) problems of the object for which the pattern function is known. The result is applied to the problems of diffraction by a half‐plane and a wedge and of scattering by a circular cylinder, and practical representations are derived. For the half‐plane problem, the results are compared with those derived by other methods and complete agreement is confirmed. Numerical calculations for the slit diffraction problem and scatterings from the cylinder result in accurate results even when the distance between the object and the source is extremely small, as long as the second or the third term is taken into consideration. The method is believed to be an effective one.
Time domain and realization of a class of digital hybrid filter
Authors: Shinnaka Shinji 
Published: July 2007

AbstractThis paper describes a time‐domain design and realization of a digital hybrid filter with a specific cutoff frequency. The proposed realization is obtained by adding a single multiplier in a feedback loop to the low‐pass or high‐pass FIR filters with linear phase. The resulting hybrid filters can have the following improved frequency response: (1) Increased attenuation in the stop‐band (compared to that obtainable with a Kaiser windowed FIR filter of the same order) for the same transition bandwidth; (2) almost constant amplitude response in the stopband and no zero‐cross ripple; (3) no degradation of phase linearity in the pass‐band; and (4) almost constant phase response in the stopband. Also the hybrid filter designed and realized in this way is always stable and does not generate limit cycles. The time‐domain design and realization of digital hybrid filters of this class are introduced and a design example of a low‐pass hybrid filter is given.
Lumped‐element representations of lossy multi‐wire lines
Authors: Kunieda Hiroaki 
Published: July 2007

AbstractLumped‐element representations are derived for lossy multiwire lines using simple circuit matrix with the assumptions that (1) phase constants of all transmission modes are identical, and (2) their attenuation constants are independent of frequencies. Since these assumptions are valid in the limited frequency range, simplified representations of lossy multiwire lines are derived in the vicinity of a quarter‐wavelength frequency. As an application of narrowband equivalent representations, analysis and design of lossy interdigital‐line filters of narrow‐band are investigated.
Optimized interpolation of discrete picture signals
Authors: Kinuhata Kouji 
Published: July 2007

AbstractThis paper describes the optimization of linear interpolation of picture elements in terms of least mean square error for pictures of a square array of elements. Two kinds of models are assumed for autocorrelation function m, n which is defined as the correlation of two elements separated m picture elements in a horizontal direction and n picture elements in a vertical direction. One is a homogeneous model in which m, n is given by the equation m, nIn the interpolation of the picture element at the point not sampled, the optimum interpolation can be achieved by the linear combination of the four picture elements nearest to the point to be interpolated. This is strictly true in the case of an inhomogeneous correlation function and approximately true in the case of a homogeneous correlation function. On the other hand, in the interpolation of the picture element at the sampling point, the interpolation can be optimized by the linear combination of eight picture elements around the point to be interpolated. This is strictly true in the case of an inhomogeneous correlation function and approximately true in the case of a homogeneous correlation function.Using the above results, interpolation techniques in “standard conversion in broadcasting television signals” and “system conversion from video phone signal to broadcasting television signal” are reviewed, and the pictures processed with the interpolation techniques are evaluated.
Theoretical analysis of distortion of simultaneous transmission systems for picture and narrowband signals
Authors: Morimoto Sei 
Published: July 2007

AbstractThis paper presents formulas for calculation of the distortion noise in picture and subcarrier FM transmission. The distortion is calculated from the transmission channel characteristics at the sideband of the FM wave which is expanded in Bessel function. FM and PSK are considered as the subcarrier modulation. The spectral models for the picture brightness signals and color signals are approximated by e‐aΔ at frequency Δ.The main results include: (1) the calculation of the distortion due to the differential gain (DG); (2) the calculation of 16 different kinds of distortions; and (3) the application to TV‐speech multibroadcasting, two‐picture simultaneous transmission, and picture‐telephone simultaneous transmission.
16‐qam carrier recovery with selective gated phase‐locked loop
Authors: Horikawa Izumi , Saitos Yoichi 
Published: July 2007

AbstractIt is important for the 16QAM carrier recovery circuit to have low phase jitter as well as only four stable phase points. In this paper, a novel carrier recovery with selective gated phase‐locked loop (PLL) is proposed which uses only the error information of the 4PSK signal and an identical phase signal; its construction and noise characteristics are also described. First, a concrete construction based on a working priciple and digitalized circuitry is given. Next, the phase jitter due to additive white Gaussian noise in a carrier tracking loop with binary phase comparator (PC) characteristic is analyzed using an equivalent linearization technique; also, it is shown that the carrier recovery loop can be described in a linear model of the past by introducing equivalent linear gain, equivalent input noise and the degradation factor caused by the symbol error. From this study, we conclude that with the selective gated PLL, the phase jitter performance of the carrier recovery can be improved by about 6 dB over that of the carrier recovery without the selective gated PLL. This has enabled us to improve the phase noise, power density, locking characteristic, tracking characteristic, etc., by about 100%. The noise characteristics are almost the same as that of 4PSK carrier recovery. The numerical calculations have been done for the equivalent PC. This recovery system does not have false lock points.
Recursive realizations of n‐th order fir filters with linear phase designed by (n‐1) point frequency sampling technique
Authors: Shinnaka Shinji 
Published: July 2007

AbstractIn determining approximately impulse responses of linear‐phase Nth‐order FIR filters by the N‐point frequency sampling method, the approximated impulse response is expressed as a sum of cosine or sine function series with phase shift corresponding to half series time width having sampled values as coefficients. On the other hand, the (N‐1) point frequency sampling method enables one to obtain the approximated impulse response in a form of a sum of cosine or sine function series without phase shift having sampled values as coefficients. In the recursive realization of triangular function series, the triangular function series without phase shift can be realized using a smaller number of multipliers than the triangular function series with phase shift. The (N‐1) point frequency sampling provides more effective recursive realization than the N‐point frequency sampling. If the normal form is used, the number of multipliers can be reduced by 33% and the processing speed and round‐off noise can be improved considerably.
Minimization of sensitivities in digital filters by coefficient conversion
Authors: Nishihara Akinori , Moriyama Yoshiaki 
Published: July 2007

AbstractIn digital filters, the response involves the error due to the finiteness of coefficient word lengths. This error is related to the coefficient sensitivity. In this paper, low‐sensitivity transfer functions are derived. With the smallest number of multipliers, the coefficients of the transfer function are derived as functions of multiplier coefficients using constant mij. Then the sensitivity of the amplitude characteristics for the multiplier coefficients is obtained as functions of real frequencients and constant mij and multiplier coefficients are determined by minimizing this sensitivity. Several low‐sensitivity transfer functions are derived and their circuits are presented.
Stability analysis of large‐scale composite systems using positivity condition of bilinear forms
Authors: Mori Takehiro , Kuwaharas Michiyoshi 
Published: July 2007

AbstractThis paper considers the positive definite conditions for bilinear forms, as obtained in the discussion of stability of discrete‐time feedback systems by Williams and Brockett, and derives several stability conditions for large‐scale systems with composite structures. Since the bilinear form includes the quadratic form as a special case, the result obtained includes typical traditional results derived from the definiteness condition for the quadratic forms. As a result of utilizing the bilinear form, the theorems in this paper can sometimes handle cases where the coupling among subsystems contains higher‐order terms, which could not be treated by most of the traditional theorems. Proofs for the theorems are given, including arbitrary parameters, but it is shown for some of the theorems that the conditions including arbitrary parameters can equivalently be replaced by algebraic conditions without such parameters. From these properties, the traditional conditions for stability including arbitrary parameters can be transformed into conditions without parameters. Several examples are shown in relation to the traditional results.
Postdetection selection diversity effects in a digital fm land mobile radio with discriminator and differential detections
Authors: Adachi Fumiyuki 
Published: July 2007

AbstractIn the digital FM land mobile radio communication with fast fading whose maximum Doppler frequency reaches several ten Hz, the error occurs due to the signal amplitude variation and random FM noise caused by the phase variation. This paper discusses the performance improvement by the postdetection selection diversity for the digital FM radio communication with discriminator and differential detections under a fast Rayleigh fading environment. The conditional error ratio is derived for the instantaneous detector input amplitude at fast Rayleigh fading and the average error rate at the diversity reception is obtained as a general solution with the effect of random FM noise taken into account. Further, the improvement effect in the presence of co‐channel interference is analyzed. The comparison is made with the postdetection synthesis diversity.
Residual stresses of fibers in tape‐type optical cable and their reduction
Authors: Yamauchi Ryozo , Inadas Koichi , Ishihara Koshi 
Published: July 2007

AbstractWhen the tape‐type optical fibers are twisted or cabled, longitudinal stress is generated in the fibers. This stress has been discussed solely as a practical problem on the stress generation among the tape‐type fibers. In this paper, a practical model is set up and calculation is conducted for the stress generated in the fibers of a tape‐type optical cable. Under the practical condition of normal tape cabling, the main stresses generated on the fiber surfaces are governed by the twists appearing on the individual fibers. The direction of the main stress caused by the twist is different from the stress direction by the conventionally applied screening strength test. Accordingly, it is needed to apply screening to the fiber elements in a tape‐type cable under more intense tensile stress. To reduce the fiber stresses generated by the fiber tape cabling, we propose a “pre‐twisting method” where the fibers are pretwisted in the opposite direction to that of tape cabling, thereby cancelling the cabling stresses. Its effectiveness has been made clear by the experiment.
Dynamic characteristics of the improved forward‐type multiple‐output dc‐dc power converter using cross regulation
Authors: Matsuo Hirofumi , Kurokawa Fujio 
Published: July 2007

AbstractThe conventional forward‐type multiple‐output dc‐dc converter has a deficiency in that when the output load current drops below a certain value, and the reactor current becomes discontinuous, or when the load changes dynamically, the cross‐regulation function is lost.The authors previously proposed a means to improve the steady‐state characteristics via a forward‐type multiple output converter in which magnetic couplings of windings in the transformer and reactor are utilized.In this paper, the improved forward‐type multiple‐output converter was studied including analysis of its dynamic characteristics. First, the steady‐state characteristic was analyzed. Second, the dynamic characteristic was disclosed in which it was shown that, due to the magnetic coupling between reactor windings and P‐D feedback control, a dynamic cross‐regulation function was obtained and even when the smoothing capacitors are relatively small, the variations of output voltages on load change are well suppressed. Further, comparisons were made with the conventional forward‐type multiple‐output converter and the superiority of the improved circuit was clearly shown.
Preparation and characteristics of PBF2‐ALF3 and PBF2‐ZRF4 glasses
Authors: Shibata Shuichi , Kanamoris Terutoshi , Mitachi Seiko , Manabe Toyotaka 
Published: July 2007

AbstractIt was found that PbF2‐AlF3 and PbF2‐ZrF4 form glasses. Glass forming regions are 30 ≤ AlF3 ≤ 60 and 40 ≤ ZrF4 ≤ 60 (mol.%). Glasses are prepared by the casting quenching technique or the roller quenching technique. Both glass systems have transmission windows in 0.3 to 9 μm wavelength region with a minimum loss band at 3 to 4 μm and are expected to have a loss of less than 0.1 dB/km.The infrared absorption edge is determined by the absorption band of AlF3 or ZrF4. The refractive index is about 1.6 to 1.7 and decreases as the amount of AlF3 or ZrF4 increases. Therefore, it is possible to design a propagation structure by controlling the amount of AlF3 or ZrF4. Their crystallization temperatures are in a range of 250 to 400°C and increase as the amount of AlF3 or ZrF4 increases. The crystallization temperature of PbF2‐AlF3is higher than that of PbF2‐ZrF4.The activation energy of crystallization is about 80 kcal/mol and therefore, is thermally stable at room temperature. Because of these results, PbF2‐AlF3 and PbF2‐ZrF4 glass systems are promising optical fiber materials for the 3‐4 μm wavelength region. Furthermore, it becomes clear that the quenching technique is an important method for making glasses from various crystals.
Cross‐correlation speed measurement using itv camera
Authors: Nagai Keinosuke , Akazawa Hideo , Idogawa Tohru 
Published: July 2007

AbstractA new method for speed measurement by correlation techniques is proposed. An image of a rough surface of a moving object is obtained every 1/30 second using an ITV camera with a rotary shutter. The displacement of the object during 1/30 second is estimated from a polarity cross‐correlation function between two successive surface images. (1) The speed v to be measured is proportional to the displacement. (2) v = O can be measured. (3) The average length for the computation of correlation function is determined from the measurement accuracy required. The time required for signal processing is less than one field period (1/60 second).
Solid‐state inductors by gic
Authors: Nakamura Masataka , Shigehiros Takanori 
Published: July 2007

AbstractThe solid‐state inductor is realized using the GIC which has the voltage‐current relations E1 = E2 and I1 = I2/Jτ at the input‐output terminals. The present GIC is composed of three transistors and suffers from the parasitic oscillation at high frequencies. This parasitic oscillation is prevented effectively by creating the transmission zeros in the loop circuits. The Q deterioration can be compensated by adding a series circuit of capacitance and resistance.The experimental inductor has the temperature coefficient 500 ppm/°C up to 1 MHz and is highly stable (high Q). Several GIC's can be cascaded with stable supply of the dc bias. This GIC is applied to bandpass filters (center frequency 455 kHz, bandwidth 21.4 kHz).
Asymptotic behavior of nonlinear discrete‐time compartmental systems—comparison with continuous‐time systems
Authors: Fukui Ayumu , Maeda Hajime , Kodama Shinzo 
Published: July 2007

AbstractThis paper derives the difference equation for nonlinear compartmental systems by means of the forward Euler method and compares the solution of the continuous‐time compartmental system with the solution of the system by the difference equation. That is, the objective of this paper is to derive the conditions under which the discretized system created by difference equation preserves the specific properties of the original continuous‐time compartmental systems (non‐negativity, monotony and non‐oscillatory properties of the solutions) and the admissible range of the step width in the difference equation. It shows that the uniformly bounded solutions with constant input can be approximated uniformly in [0, ∞) by the solutions of the difference equation with arbitrary small errors. Furthermore, it derives the condition under which the accumulated round‐off errors become uniformly bounded for uniformly bounded round‐off errors.
Design of new predictor using covariance information and its application to prediction of air pollution levels
Authors: Nakamori Seiichi , Hatajis Akira 
Published: July 2007

AbstractThis paper presents a new, linear continuous predictor based on innovation theory using covariance information on data to be predicted as a statistical non‐physical model. Model simulation is performed to investigate the effectiveness of the proposed predictor. The predictor obtained for the case when observed noises are stationary white + colored noises is seen to exhibit reasonable prediction and white noise characteristics. As its practical application, the predictor is used to predict SO2 levels and the SO2 data thus obtained is compared quantitatively against the prediction by conventional auto‐regressive model based on MEM. As a result of experiments, the effectiveness of the predictor is assumed.
256‐bit elastic store cmos LSI
Authors: Fukuda Hideki , Yasukawa Hiroshi , Ohwadas Norihiko 
Published: July 2007

AbstractThis paper reports the design and characteristics of the 256‐bit elastic store (ES) CMOS LSI. The elastic store circuit absorbs phase differences of signals and is one kind of First‐In‐First‐Out (FIFO) Read/Write memory with the function of application to multiplex. The circuit is equipped with an elastic function which can perform write and read of the data independently and other functions such as reset and inhibit of the address counter and phase comparator. As CMOS circuits, NAND gate at store cell and D‐F/F with reset terminals at address counter are used to obtain stabilization, high‐speed operation and low‐power consumption. As the result of a prototype LSI, a performance at more than 9 MHz under the worst condition of VDD = 4.75 V and Ta = 70°C and the characteristics of high speed and low power consumption of 125 mW have been obtained. Its possible application to various equipment for digital network in PCM secondary group is discussed.
Fine pattern technology for multilevel metallization with piq insulation
Authors: Saiki Atsushi , Mukai Kiichiro , Haradas Seiki , Okubo Toshio 
Published: July 2007

AbstractPIQ (patented) is known to be a very effective polymer for use in planar multilevel interconnection technology. To realize fine patterns and a high order of integration of this technology, we studied a wet‐etching mechanism with an etchant based on hydrazine hydrate. Hydrazine hydrate is known to be an etchant for the PIQ, as are also NaOH and KOH. However, hydrazine hydrate is not suitable for fine‐pattern technology because it causes a region of swelling in PIQ film. We analyzed the swelling region by infrared spectroscopy and found that ethylenediamine solves the swelling quite effectively. Based on these results, we developed a new etchant containing hydrazine hydrate and ethylenediamine. The new etchant enables the creation of stable 3 μ2 via‐holes in the PIQ film. The electrical properties of these holes are also found to be quite good.
Consideration on fine‐patterning techniques in eb lithography
Authors: Sugiyama Naoshi 
Published: July 2007

AbstractThe corrections on the beam distortion and proximity effect in the electron‐beam lithography are discussed from the viewpoint of computer processing. The coefficient parameters of the beam‐deflection‐distortion mapping function are estimated by the least square method from the measurement data of the beam deflection distortion, and the error distribution is clarified. The measurement errors in the movement and rotation of the sample desk are minimized. For the proximity effect correction at the rectangular beam illumination, the illumination intensity distribution function is approximated to the trapezoidal form and the computer simulation is made for the calculation of the exposure dose. Finally, the dependences of the beam scanning direction and the scanning interval on the proximity effect are examined by computer simulation.
Analysis of a binary quantized dpll by equivalent analog model
Authors: Kurita Taiichiro , Mori Shinsaku , Ozawas Shinji 
Published: July 2007

AbstractA binary quantized digital phase‐locked loop (DPLL) is a class of digital PLLs having advantage of its simplicity and high reliability. This class of DPLL has been analyzed by applying Markov theory. However, this method has a limited range of applications and the numerical solutions of the performances have not been obtained without using a computer. In this paper, a binary quantized DPLL is analyzed by replacing the DPLL with the equivalent linear and nonlinear analog PLL. This equivalent method of analysis can be applied to more general cases. The numerical results agree with those of experiments.