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We have introduced a correlating synthesis (CS) method for high-resolution terahertz (THz) imaging. The efficiency of the CS method was verified by imaging experiment of metal cylinders using a pulse reflection mode terahertz time-domain-spectrometry system. In this paper, we study the influence of layered dielectric in the propagation path of THz wave. A method of propagation time correction by ray tracing in the dielectric layer is proposed. The efficiency on decreasing the distortion and artifact images is verified by imaging experiment with a dielectric substrate board. Moreover, it is noticed that the appropriate correlation interval used in CS processing depends on the shape of the target. We propose a method of synthesizing the images derived from a series of different correlation intervals, which ensures the robustness of parameter independent with the target. The efficiency of the proposed method is verified by comparison imaging experiments using samples of different targets on a substrate board.

In the application of 2-D adaptive filters, a large amount of data must be processed and real-time processing is often required. In this paper, a new parallel-form realization of 2-D adaptive separable-denominator state-space filters suitable for high-speed processing is proposed. First, the 2-D local state-space model suitable for parallel processing is introduced. Next, the adaptive algorithm for this model is developed. This algorithm is based on the delayed least mean square (DLMS) method. In addition, the computation time required for the update of the coefficients is investigated. Finally, the proposed technique is applied to the design of 2-D digital filters in the spatial domain.

This paper proposes a realization of a two-dimensional adaptive state-space filter for parallel processing using state-space model with a general form. For the modeling of the filter, a generalized model realized for parallel processing is used and the conventional denominator-separation type model is extended. Further, the LMS (Least Mean Square) algorithm is used to construct an adaptive algorithm and its processing speed and computational effort are evaluated. By means of this method, the hardware content can be reduced while the processing speed is maintained almost the same as in the complete generalized model. Finally, in order to verify the effectiveness of the present method, an example is presented in which a two-dimensional adaptive filter is applied to the spatial domain design as a system identification problem. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 86(1): 46–57, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10019

This paper introduces the parallel processing into the separable-denominator 3-D adaptive state-space filter, and discusses a realization method which is suited to the high-speed processing. the LMS (least-mean-square) algorithm is used as the adaptive algorithm, and the parallel processing-oriented structure of the separable-denominator 3-D filter is used as the filter model. The parallel processing-oriented structure of the 3-D adaptive state-space filter is obtained by extending the adaptive algorithm of the 2-D state-space adaptive filter to the above 3-D structure. the proposed algorithm is evaluated in this paper in terms of the time required for the filtering and the coefficient update, as well as the number of multipliers (adders). Finally, the proposed adaptive filter is applied to the design of the 3-D state-space digital filter, and the effectiveness of the algorithm is demonstrated.

This paper introduces a new effort by the Object Management Group to standardise the format of information used in the assurance of safety-sensitive consumer devices, such as automobiles and service robots. The diversity of device types and development approaches for such devices makes the sharing and re-use of assurance information difficult. The new standardisation effort aims to resolve this issue through common information models and consistent argument structures.

This paper considers the realization of three-dimensional (3-D) adaptive separable-denominator state-space filters suitable for parallel processing. The least mean squares (LMS) algorithm is used to adjust the filter parameters. First, a 3-D local state-space model which is separable in the denominator is realized in a parallel form. Next, the LMS algorithm is employed to adjust the filter parameters in the parallel form. In addition, the computational time and the number of multipliers (adders) required for the realization are estimated. Finally, in a numerical example, the present adaptive filter is applied to the problem of designing a 3-D digital filter in the spatial domain.