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Naoki KOBAYASHI Kaoru NARITA Taras KUSHTA Hirokazu TOHYA
We have developed an algorithm called the "spectral-domain-to-real-space approach" (SDRSA) to analytically calculate radiation from the two-dimensional current density distribution in microstrip line configurations where the microstrip lines are represented in the form of a three-dimensional inhomogeneous structure. The algorithm is based on the spectral-domain approach used to estimate radiation from microstrip line configurations. Calculation results obtained by using the SDRSA and the current density distribution from a quasi-TEM mode model of microstrip lines agree well with the corresponding estimations obtained by using the equivalent electric current source method and the magnetic current source method, and with the experimental results obtained in the frequency band of up to 1 GHz.
Kazuma SHINODA Naoki KOBAYASHI Ayako KATOH Hideki KOMAGATA Masahiro ISHIKAWA Yuri MURAKAMI Masahiro YAMAGUCHI Tokiya ABE Akinori HASHIGUCHI Michiie SAKAMOTO
Region of interest (ROI) coding is a useful function for many applications. JPEG2000 supports ROI coding and can decode ROIs preferentially regardless of the shape and number of the regions. However, if the number of regions is quite large, the ROI coding performance of JPEG2000 declines because the code-stream includes many useless non-ROI codes. This paper proposes a wavelet-based ROI coding method suited for multiple ROIs. The proposed wavelet transform does not access any non-ROIs when transforming the ROIs. Additionally, the proposed method eliminates the need for unnecessary coding of the bits in the higher bit planes of non-ROI regions by adding an ROI map to the code-stream. The experimental results show that the proposed method achieves a higher peak signal-to-noise ratio than the ROI coding of JPEG2000. The proposed method can be applied to both max-shift and scaling-based ROI coding.