In multidimensional signal sampling, the orthogonal sampling scheme is the simplest one and is employed in various applications, while a non-orthogonal sampling scheme is its alternative candidate. The latter sampling scheme is used mainly in application where the reduction of the sampling rate is important. In three-dimensional (3-D) signal processing, there are two typical sampling schemes which belong to the non-orthogonal samplings; one is face-centered cubic sampling (FCCS) and the other is body-centered cubic sampling (BCCS). This paper proposes a new design method for 3-D band-limiting FIR filters required for such non-orthogonal sampling schemes. The proposed method employs the McClellan transformation technique. Unlike the usual 3-D McClellan transformation, however, the proposed design method uses 2-D prototype filters and 2-D transformation filters to obtain 3-D FIR filters. First, 3-D general sampling theory is discussed and the two types of typical non-orthogonal sampling schemes, FCCS and BCCS, are explained. Then, the proposed design method of 3-D bandlimiting filters for these sampling schemes is explained and an effective implementation of the designed filters is discussed briefly. Finally, design examples are given and the proposed method is compared with other method to show the effectiveness of our methos.

A new trial of statistical evaluation for an output response of power linear type acoustic systems with nonstationary random input is proposed. The purpose of this study is to predict the output probability distribution function on the basis of a standard type pre-experiment in a laboratoty. The statistical properties like nonstationarity, non-Gamma distribution property and various type linear and non-linear correlations of input signal are reflected in the form of differential operation with respect to distribution parameters. More concretely, the pre-experiment is carried out for a power linear acoustic system excited only by the Gamma distribution type sandard random input. Considering the non-negative random property for the output response of a power linear system, the well-known statistical Laguerre expansion series type probability expression is first employed as the framework of basic probability distribution expression on the output power fluctuation. Then, the objective output probability distribution for a non-stationary case can be easily derived only by successively employing newly introduced differential operators to this basic probability distribution of statistical Laguerre expansion series type. As an application to the actual noise environment, the proposed method is employed for an evaluation problem on the stochastic response probability distribution for an acoustic sound insulation system excited by a nonstationary input noise.

This paper proposes a technique for estimating speech parameters in noisy environment. The technique uses a spectral model represented by generalized cepstrum and estimates the generalized cepstral coefficients from the speech which has been degraded by additive background noise. Parameter estimation is based on maximum a posteriori (MAP) estimation procedure. An iterative approach which has been formulated for all-pole modeling is applied to the generalized cepstral modeling. Generalized cepstral coefficients are obtained by an iterative procedure that consists of the unbiased estimation of log spectrum and noncausal Wiener filtering. Since the generalized cepstral model includes the all-pole model as a special case, the technique can be viewed as a generalization of the all-pole modeling based on MAP estimation. The proposed technique is applied to the enhancement of speech and several experimental results are also shown.

In this paper, we evaluate the sustained performance of the prototype SHD (Super High Definition) image processing system NOVI- HiPIPE, and discuss the requirements of a real-time SHD image processing system. NOVI- HiPIPE is a parallel DSP system with 128 PEs (Processing Elements), each containing one vector processor, and its peak performance is 15 GFLOPS. The measured performance of this system is at least 100 times higher than that of the Cray-2 (single CPU), but is still insufficient for real-time SHD image coding. When coding SHD moving images at 60 frames per second with the JPEG algorithm, the performance must be at least ten times faster than is now possible with NOVI- HiPIPE. To extract higher performance from a parallel processing system, the system architecture must be suitable for the implemented process. The advantages of NOVI- HiPIPE are its mesh network and high performance pipelined vector processor (VP), one of which is installed on each PE. When most basic SHD image coding techniques are implemented on NOVI- HiPIPE, intercommunication occurs only between directly connected PEs, and its cost is very low. Each VP can efficiently execute vector calculations. which occur frequently in image processing, and they increase the performance of NOVI- HiPIPE by a factor of from 20 to 100. In order to further improve the performance, the speed of memory access and bit operation must be increased. The next generation SHD image processing system must be built around the VP, an independent function block which controls memory access, and another block which executes bit operations. To support the input and output of SHD moving images and the inter-frame coding algorithms, the mesh network should be expanded into a 3D-cube.

We have calssified parenchymal echo patterns of cirrhotic liver into four types, according to the size of hypoechoic nodular lesions. Neural network technique has been applied to the characterization of hepatic parenchymal diseases in ultrasonic B-scan texture. We employed a multi-layer feedforward neural network utilizing the back-propagation algorithm. We carried out four kinds of pre-processings for liver parenchymal pattern in the images. We describe the examination of each performance by these pre-processing techniques. We show four results using (1) only magnitudes of FFT pre-processing, (2) both magnitudes and phase angles, (3) data normalized by the maximum value in the dataset, and (4) data normalized by variance of the dataset. Among the 4 pre-processing data treatments studied, the process combining FFT phase angles and magnitudes of FFT is found to be the most efficient.

An adaptive signal processing using Acoustic Charge Transport device, which has great potential for processing very wide band signals in real time, is investigated. It shows that adaptive system for signals of bandwidth from dc up to 500 MHz can be implemented in real time.

High speed multiplication of two n-bit numbers plays an important role in many digital signal processing applications. Traditional array and Wallace multipliers are the most widely used multipliers implemented in VLSI. The area and time (=latency) of these two multipliers depend on operand bit-size, n. For a particular bit-size, they occupy fixed positions in some graph which has area and time along the x and y-axes respectively. However, many applications require a multiplier which has an 'intermediate' area-time characteristics with the above two traditional multipliers occupying two extreme ends of above mentioned area-time curve. In this paper, we propose such an intermediate multiplier which trades off area for time. It has higher speed (i.e., less latendy) but more area than a traditional array multiplier. Whereas when compared with a traditional Wallace multiplier, it has lower speed and area. The attractive point of our multiplier is that, it resembles an array multiplier in terms of regularity in placement and inter-connection of unit computation cells. And its interesting feature is that, in contrast to a traditional array multiplier, it computes by introducing multiple computation wave fronts among its computation cells. In this paper, we investigate on the area-time complexity of our proposed multiplier and discuss on its characteristics while comparing with some contemporary multiplers in terms of latency, area and wiring complexity.

This paper describes a new automated approach to generating the patterns of CMOS leaf cells from transistor-level connectivity data. This method can generate CMOS leaf cells that are configurable to a macro cell satisfying user-specified constraints. The user-specified constraints include the aspect ratio and port positions of the macro cell. We propose a top-down method for converting the macro cell level constratints to leaf cell level ones. Using this method, a variety of customized macro cells can be designed in a short turn-around time. The method consists of four processes--diffusion sharing, initial placement, placement improvement and routing--which culminate in the automatic generation of symbolic representations. Using a compactor, those symbolic representations can be converted to physical patterns which are gathered into a macro cell by a macro generator. We define various objective functions to improve unit pair placement. We also introduce five ways to optimize leaf cell area: 1) multi-row division, 2) gate division 3) rotation, 4) power line and diffusion overlapping and 5) reconstruction of hierarchical structure. The proposed approach has been applied to various kinds of CMOS leaf cells. Experimental results show that the generated cells have almost the same areas as those generated by conventional bottom-up approaches in leaf and macro cell layouts. This approach offers a further advantage in that the various-sized macro cells required by layout disigners can also be generated.

The physical system is considered more suitable for measurement purposes the greater is its linearity. However, in nature and engineering there are no purely linear physical transducing systems for convertion a primary onformation. The use of the linear features of the system in the measurement process finally causes the drawbacks: systematic error due to nonlinear distortions, low ratio informative signal/ noise, the necessity to evaluate a great number of the a priori parameters of the transducer in order to receive an absolute result, low thermostability because every a priori parameter itself has a temperature dependence. To exclude these drawbacks a method has been developed using nonlinear physical systems in the base of the displacements measurement. In this work is presented the realization of the method using electretic and electrostatic transducer as a converting physical system. A contactless transducer is placed parallelly to the surface of the object which displacements are measured. The transducer is driven to harmonic oscillations. Typical time intervals between even and odd extremums of the transducer output signal are measured. The object displacements are determined according to the changes of the typical time intervals. The method itself has no errors because approximations were not made while deriving the relations. The source of the errors is inaccurate registration of the start and the end of the typical time intervals. In the work are analysed the errors related to the concrete realization devices: analogue differentiator, peak detector and analog digital transducer. It is shown that the measurement is possible only if the physical system is nonlinear. The method is generalized to that case if the function of transformation of ths system has the form f(x) and monotonous character. The results of experimental investigations confirm the theoretical conclusions.

An adaptive multichannel IIR lattice predictor for k-step ahead prediction is constructed and the effectiveness of the proposed predictor is evaluated using digital simulations.

In this paper, we attempt the comparison of the image/signal restoration between Projection Filter, which is regarded as one of the linear optimal filters, and the non-linear filter based on MEM. From the simulation, we show the advantage of MEM restoration filter in restoring noisy degraded images.