[in Japanese]

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We propose BO coded and picture command transfer methods for picture transfer in a personal computer network.
The BO coded transfer method is based on byte oriented data compression by pixel “1” / “0” transition frequency in a raster line.
The picture command transfer method is to transfer a command form program instead of raw picture data. This method requires transferring much less data than with the raw picture data method, and is suitable for motion picture transfer.
Experimental comparison results and evaluation are presented. Some functions of the proposed methods have already been applied to practical use in TV weather broadcasting.

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Three or four companded sound channels accompanying teletext programs can be placed in the back porch of HBL. In this experimental system, a adaptive delta modulation (ADM) scheme with syllable companding is adopted. The audio signal dynamic range level is greater than 45dB and the distortion factor is less than 4 percent. Preliminary experimental results show that an ADM-HBL multiplex sound system is compatible with TV broadcasting and teletext. Its tone quality can satisfy the requirements for additional teletext sound. Because the text signal and sound signal are designed together, the receiver circuits are simplified.

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A new equalization method based on both the nonlinear equalization technique, called Linear Canceller, and probablistic decoding technique is proposed for high rate recording systems. Error rate improvement of more than two orders can be achieved by applying this method to an experimental digital VTR. Moreover, a new automatic equalizing algorithm is proposed. This algorithm has an advantage in that the automatic equalizer is constructed easily with not only digital circuits, but also with analog circuits. An adaptive automatic equalizer with a variable part constructed with all digital circuits is implemented. It is confirmed that sufficient eye opening is achieved using this algorithm at an operation speed of 46 Mbps.

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Magnetic focusing and electrostatic deflecting (MS) camera tubes have been investigated concerning a twist angle of the Pattern yoke and the shielding electrode for deflection field near the electron gun by calculating the deflection electrostatic field using the variable separation method.
It was found that a twist in the pattern yoke by 30 degrees reduces the beam spreads due to deflection aberrations and improve the resolution uniformity over the raster. It was also found that the shielding electrode is efficient for improving resolution.
The 2/3 inch MS camera tubes based on the calculation are fabricated and show good resolution. The performances of the tubes are found to be in very good agreement with calculations. Cameras using the tubes are also fabricated. The optimization of the MS electron beam systems have been established.

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Using a nonplanar aperture-type E-plane cosecant beam horn as an element antenna of a cosecant-beam array is proposed.The experimental results show that the radiation field density in the service area is under ±3dB and the service area spill over is very small.

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