We studied a control method of Dynamic Focus for High Resolution Wide Display, using DC correction voltage derived from DF waveform itself instead of special clamp circuit inside the FBT.

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We have studied a field-sequential stereoscopic display system with HDTV PDP and confirmed that a field-sequential stereoscopic image can be displayed with currently available PDP panels. However, the cross-talk impairment between left and right images is more visible for a PDP display than a CRT display. We have proposed a new method to reduce the dross-talk by signal processing. Improvement of the processing is discussed.

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The progress of Picture display mode in TV is described on a view of flexibility of PinP, Split, P&P, index mode, and another view of picture quality improvement by progressive double scanning and HD quality display for Digital Broadcasting receiver. This HD displaying IC is introduced.

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In this paper, We propose diversity reception of an OFDM signal using pilot symbol assisted channel estimation, which is effective to improve the bit error rate characteristic under confirmed that the bit error rate characteristics is better than the signal antenna receiver.

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We have already proposed that a pilot symbol assisted equalizer in OFDM that estimates complex attenation factor and delay time of multiple. In this paper, we analized bit error rate in the proposed method with using various parameters.

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An Orthogonal Frequency Division Multiplexing (OFDM) is one of the multi-carrier moduration schemes. Its signal is made of a lot of synthesized data which is divided into orthogonally arranged carriers in frequency axis. As carriers are orthogonal to each other, it is possible to use frequency band efficiently. And OFDM is not much affected by multipath interferences because its symbol length can be made very long, and inter-symbol interference is eliminated by adding a guard-interval part to the OFDM symbol. In a Signal Frequency Network (SFN) environment, a multipath is usually exists and the characteristic of reception of OFDM signal is affected. In mobile reception of OFDM signal, it is very serious. In this paper, the characteristics in mobile reception of OFDM signal under SFN environment are theoretically analyzed.

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In TV relay stations for SFN(Signal Frequency Network), it is a proble that the coupling between transmitting antenna and receiving antenna may cause distortion and oscillation. To study a possibility of suppressing the couplin, we have developed Coupling Wave Canceler for DQPSK-OFDM using adaptive signal processing techinique. Experiments and computer simulations are carried out on the performance of the canceler. The canceler can reduce BER at a CN ratio of 18dB from the order of 10<-2> to 10<-6>.

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So far, the maintenance of antenna system in broadcast, what is a important media system in high informed society present day, needs many times and many cost. But recentry the time of maintenance for antenna system in broadcast is shorter than the time when is needed for maintenance. Broadcast Antenna measure & detective system is measuring a individual antenna on broadcast antenna system, and detecting an abnormal antenna. Because, for using this system the maintenance time is very shorter than when not using. We will report the sencer and the equipment of this system.

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In active phased array flat antennas, mutual effects between antenna elements and power amplifiers mounted on the antenna panel may degrade antenna performance such as pointing accuracy. To evaluate the effect, we calculated and measured the influence on the phase and amplitude of the radiated waves due to mutual coupling between antenna elements.

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This paper presents a reinforcing method for TV tower on which existing antenna panels are closely combined. The method is that after projecting antenna element forward during on-air, the reinforcement work has been done between tower face and antenna element while reducing the change of the radiation pattern of the antenna as much as possible.

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The field strength simulation system "ERIAKAKUBEH" which we had developed at last year is now improving to receive various responses about the functions, method of simulation and GUI from users. This paper described the new method to calculate the under beam loss "diffraction loss of under line-of -sight" in the propagation of electromagnetic wave.

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The Communication Research Laboratory (CRL) is providing sounding data(Ionograms) of various ionospheric via the internet, including sporadic-E. We find the tendency between abnormal propagation caused by Sporadic-E ionosphere and daily transition pattern of ionograms.

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We are investigating optical video-routing networks using dense-WDM technique. This paper describes the tuning characteristics of an optical Fabry-Perot filter with a narrow bandwidth. We designed and manufactured a Fabry-Perot Ti-diffused LiNbO_3 optical waveguide filter. We improved its transmission characteristics by means of widening a waveguide. We also confirmed its fast switching characteristics.

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We purposed a new measurement method of ingress noise on CATV upstream. Our experimental results show that ingress noise is detected by probability density function (PDF) of noise better than mean noise power.

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Error vector measurement is one of the effective methods to measure digitally modulated signal quality. An error vector measuring system, composed by universal equipments, is developed. Evaluation of OFDM signal passed through the CATV channel reveals that intermodulation product of NTSC signal is the most influential interference.

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We developed digital cable transmission system which re-transmits signals from satellite broadcasting to CATV. This system consists of Trans-modulator and cable Set Top Box. Trans-modulator is very compact, and cable Set Top Box is identical design for a satellite one. It enables common service distribution between satellite and cable.

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We have made an experiment on wireless CATV transmission using 23GHz band. We have measured BER of 64QAM signals and D/U ratio degradated by multipath wave. In this paper its experimental results are described.

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The bi-directional communication of between two local networks using high speed (155Mps) optical wireless LAN system that has two local routers. The local router for long distance (about 6Km) communication using optical wireless LAN system has a direction line switching to backup line function for non symmetrical line down and no switching to backup line function until data rate under backup line rate or line down at a moment has happened by the influence of weather and also has original routing function. So, we develop embedded local router for optical wireless LAN system using PC Unix kernel, as the result, we confirm the router has practical ability in optical wireless network use.

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Until now we could not measure the characteristics of broadcasting equipment while TX is in service, because special test signal is required for getting them, that is to say, we needed closing down or scheduled and limited maintenance period. Therefore we have developed "A new measuring system for getting transmission characteristic", which gets the characteristics from FFT and computer processing orthogonal coherent detected transmitting input signals and its corresponding output signals. Accordingly it is possible for us to measure transmitting equipment characteristics without scheduling maintenance shutdown.

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The digital terrestrial television broadcasting (DTTB) will start in 2000 in Japan. The link budget is calculated based on the bit error to realize the DTTB. The Gaussian Noise is used to obtain the bit error rate, but the noise in the city is impulsive and its amplitude probability density is not Gaussian distribution. In this paper, the influence of the impulse noise on DTTB is mentioned and measurements of the noise characteristics in VHF band and UHF band are described.

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BS digital broadcasting begins in 2000. 4 digital waves join 4 current analog waves and BS become 8 waves. At television reception facility, it is predicted the inetermodulation distortion (IM) causes the deterioration of picture to analog channel. In the inspection, I understood the affect was a little in the reception facility where at present it is applied finely.

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We fabricated an 8-bit full digital image sensor in which each pixel consists of a photo-diode(PD), a 1-bit A/D converter and an 8-bit pulse counter and output as 8-bit signals. The device operates by means of a standard TV system and 2-D real-time images are obtained.

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High-speed image is a very important technology especially for robot vision. However, in ordinary high-speed image sensor, the SNR of high-speed image is degraded due to the shorter signal charge accumulation time, unless expensive image intensifier is used. In this paper, a new high-speed CMOS image sensor with sensor with non-destructive interpolated imaging mode is presented. Applications to motion vector estimation and a high SNR imaging of moving object are also described.

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A new CMOS image sensor that performs bidirectional multiple charge transfer within the pixel and the ability high speed non-destructive interpolated image sensing is proposed/ This paper describes basic operation and the simulation result of the proposed image sensor. The algorithm to obtain high precision video rate motion vectors from high speed interpolated images is also described.

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In biological vision, the retina is organized into a space-variant sampling structure including a high-resolution, small central fovea, and a periphery whose resolutionlinearly decreases in steps. By this characteristic, it able to centralize and distribute the processing loads in the earliest stage vision. Therefore it is essential for smart sensing to integrate functions of spatially variant flexible sampling control system onto computational sensor. The integration on the sensor focal plane results in enhancement of performance of an image sensor.

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An active pixel sensor employed hierarchical structure is proposed and designed. It consists of local, nearest neighbor and global signal processing levels, which make it possible to design the function at each level independently. 1.2 μm CMOS process is used to design a test chip with 16 × 16 pixels.

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We have fabricated a high speed version Artificial Retina LSI. The small data size(1024 data / frame for 2D images, 64 data / frame projection images) and its high functionality I/O specification is suitable for the combination with a low power microcomputer to build up a low cost and high speed image processing system.

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This paper presents a logarithmic compression active pixel sensor that allows to cancel fixed pattern noise (FPN). The proposed technique uses a three transistor configuration. One of these transistor is used for FPN cancellation as well as logarithmic compression. The reset operation to cancel FPN cases nonlinearity in low illuminance level due to the transient response to charge the stray capacitance. The behavior is examined with the calculation and the simulation.

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We have been investigating a novel smart sensor in which every pixel independently controls its integration time. The integration time is controlled so that it has higher temporal resolution and wider dynamic range. In this paper, we describe circuit and layout of new adaptive-integration-time image sensor which has 128×64 pixels. We have designed the prototype by using a column parallel architecture.

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A dynamic range expansion method for a CMOS image sensor is proposed. The image with column parallel read-out consists of a 90×120 array of pixels, signal comparators, counter-memories and an adder. Counter-memories store the number of times when the signal accumulated in each PD reaches to the threshold level. The test device included 2 bit counter-memories for each pixel realized to extend the dynamic range.

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A new CMOS image sensor with wide dynamic range is proposed. Each image cell of this image sensor has two outputs. One is photo-intensity analog output, and the other is pulse signal which is generated by an external reset signal when output voltage of a photo diode reaches threshold level. Combination of these outputs has wide-range photo-conversion characteristics in comparison with conventional CMOS image sensors. Several image sensor architectures using this image cell are proposed.

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We have developed a 1/6-inch format 380,000 effective pixel IT-CCD image sensor. In spite of reducing the unit cell size, it has achieved excellent characteristics and low power consumption.

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The macroscopic saturation signal level fluctuation strongly depends on substrate impurity concentration fluctuation. However, the origin of the microscopic saturation signal level fluctuation has not been clarified, yet. It is suggested, in this paper, that the adherence of impurity into microscopic lattice defects causes the signal level fluctuation.

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We propose a CCD register that is suitable for highly photo-sensitive frame transfer scheme image sensors. The specific features of the proposed register highly photo-sensitive extremely low dark current and no blooming. The operation of the register was examined by using three-dimensional analysis. The analysis indicated that the charge transfer of the register was successfully achieved by driving it from the back electrodes through the barrier.

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In order to reduce distortion caused when the sensitivity of the New Super-HARP Image Sensor is Decreased by lowering the applied target voltage, we suggested that dark current in the non-scan area should be suitably increased. So as a first step, we manufactured a target that is Te-doped in its non-scan area, and measured the time required for the disappearance of distortion. As a result, under a certain condition, it took less than 1 minute with a Te doped target, while it took 4 minutes and 30 seconds with a conventional one.

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The photocurrent multiplication due to impact ionization was observed in the a-Si:H/a-SiC:H staircase photodiode. On the staircase photodiode with one band offset, the photocurrent was multiplied double and the multiplication gain of about 6 was also obtained on the staircase photodiode with 3 band offsets. It was confirmed that almost all electrons were multiplied after they crossed the band offset. To clarify the excess noise characteristic of the a-Si:H/a-SiC:H staircase photodiode film, shot noise characteristics of the photodiode film with one and three linearly graded-gap region was investigated. The excess noise factor of the staircase photodiode is remained one even the photocurrent is multiplied. From these results, it is found that the a-Si:H/a-SiC:H staircase photodiode film with the graded-gap region is not generated extra noise during the photocurrent multiplication.

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A gain control amplifier with balancing for CCD image sensors is presented. The proposed analog white balancing allows us to achieve higher SNR in the amplified image sufficient gain precision is 10 bit and low power dissipation. The power consumption is estimated to be 110mW at supply voltage is 3.3V and 20MHz pixel rate.

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In this paper, we propose a new color interpolation for still camera image based on spatial correlations in RGB cells. The missing color cells are estimated from the peripheral R, G or B cells. This algorithm calculates the ratio of known pixel in target location to known neighborhood pixel and interpolates missing pixels.

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An experiment of high-light-compressing image acquisition is described. The experimental system consists of a CCD camera and a transmissive liquid crystal display which a relay lens and a signal processor. An exposure at each pixel is controlled to avoid the photo-diode saturation and take a wide dynamic range picture.

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This paper presents a new pixel-slide method using optical devices for digital cameras with a Bayer CFA CCD to achieve the high resolution. Optical devices consist of polarozation filter and liquid crystal filter to shift a image by 1/2 pixel diagonally. Forthermore the authors have developed interpolation method which takes advantage of color signal correlation to convine two image when pixel-sliding. The effectiveness has been established because the image with CCD(100M pixels) show that it makes the resolution higher than 1600TV lines.

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The resolution of the CCD image sensor is determined by a number of pixels. If an input image, which has the frequency components higher than Nyquist frequency, are picked up by CCD image sensor, its generates aliasing. In this paper, in the simulation, high frequency components beyond Nyquist frequency were successfully reproduced by low-pass filters and digital signal processing. Using this method, the resolution of the CCD image sensor can be progressed more than twice as high as the Nyquist frequency.

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Resolution progress of image sensor by digital signal processing was simulated on computer. By this method, high-resolution images that have high spacial frequency beyond the Nyquist frequency can be obtained. Simulated imaging device is area charge-coupled device (CCD) image sensor. After the simulation, reproduced images which have frequency components twice higher than Nyquist frequency are successfully obtained. Using this method, it is possible to enhance the resolution of CCD image sensor twice as high as its inherent resolution.

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A newly developed miniature CCD camera with a focusing mechanism and dynamic range extension function is described. We developed an electrostatic linear microactuator with a large movement range employing a vibrating motion. And we tried to extend color camera dynamic range using electronic shuttering scheme. This paper shows its experimental results.

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The cata-dioptric system for the CCD micro camera was developed. The micro CCD camera is used for the visual inspection on inner surface of I.D 10mm tube. The cata-dioptric system has following merits: the optical path is short, the assembly operation of the micro CCD camera is easy and it is suitable for a miniaturization of the system. The diameter and the length of a lens are 3mm and 1mm respectively. In order to improve the optical characteristics, we developed parts to prevent flare in the image.

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This paper discribes a new method that estimates noise and removes it of meteorological satellite NOAA data by not smoothing. Quallity evaluation and noise removal is carried out by using fixed PN codes in HRPT format and the value of the vicinity of noise in AVHRR data.

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In this paper, we propose the method of cloud area extraction from NOAA image. It did the inspection of the cloud area extraction of one by one by using brightness temperature and albedo. And, we proposed the cloud the extraction algorithm that we are able to use with many images.

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We propose a method to extract cloud region from GMS split-window data. This algorithm has three tests and it identify a pixel as cloud-free only if all tests prove negative. In the third test using standard deviation, we adopt the judgment by histogram to prevent a pixel in oceanic fronts misclassified into cloud.

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This paper discribes a method of generation of GMS image matched with TRMM data and estimation of rainfall from is estimated by kind of cloud types.

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This paper describes generation of remaining error datasets and new precise correction for GMS images. Generated datasets is consist of 5 images and 4 values, those used for acquisition of remaining error determination and disclosed on World Wide Web. New precise correction method is transformation on small blocks. This method proposes GMS images within 1 pixel error.

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