This paper proposes a novel division transmission method for using multiple carriers to send a highspeed MPEG-2 TS signal that cannot be sent by conventional methods within one cable TV channel (6 MHz bandwidth) transmission capacity.To meet the above requirement, we developed a flexible absorption technique of time lag between divided TS signals, and devised a new descriptor for the MPEG-2 TS. We made an experimental transmitter and a receiver, and evaluated transmission performance of these devices. Our tests show that the receiver can absorb the time lag between divided signals up to 1.36 ms, and this corresponds to a difference of more than 272 km in the transmission distance. Furthermore, experiments with prototype devices proved that the new descriptor enables the receiver to re-compose the original high-speed MPEG-2 TS automatically.

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This paper describes simulation-based electronic teaching materials for an Introductory Communication Engineering Course.They include computer graphics animation and audio navigation and explanations. The CG-based interactive simulation content was produced for items difficult for students to understand. Investigation into its usability suggest that (1) virtual experiences through interactive CG on a PC would promote the learning by students, and (2) in addition to visual information, audio navigations, and explanations through synthesized voice would make the electronic teaching materials more effective.

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The digital broadcasting services are expected to be more popular because of their high quality and bandwidth efficiency. In Japan, a digital broadcasting service was started with a broadcasting satellite (BS) in geostationary orbit at 110 degrees of east longitude. Previously, digital broadcasting services using communications satellites (CS) has already been introduced in Japan since June 1996. Today, services are provided with three satellites, JCSAT-3 (128°E) and JCSAT-4A (124°E) for SkyPerfecTV!. Since both BS and CS are operating at the 12-GHz band and the BS and CS receiversuse similar blocks, we can reduce the total LSI size by using common components if the BS and CS receivers are implemented on the same LSI. This paper describes a VLSI demodulator architecture for both the digital BS broadcasting service based on ISDB-S (Integrated Services Digital Broadcasting Satellite) standard and the new digital CS broadcasting service based on DVB-S (Digital Video Broadcasting for Satellite) standard. We have also evaluated the LSI's performance with computer simulation and amount of hardware.

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To replay baseball highlight scenes in live broadcasts to baseball fans outside, image processing, such as analysis, meta information extraction, and automatic editing, has to be performed in real time. This paper proposes high-speed image processing that automatically extracts PC (Pitcher and Catcher) scenes from live broadcasts of a baseball game in real time using a feature mining technique as a part of baseball highlight scene delivery. This method achieves an F-measure of 97.2% and a processing speed 30 times faster than actual time.

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It is difficult to improve the performance of OFDM transmission by equalizing the channel characteristic under severe frequency selective fading conditions. Transmission diversity and data symbol spreading in the frequency domain are effective schemes for improving BER characteristics, and more improvement can be achieved by combining them. Moreover, further improvement should be achieved by controlling the sub-carrier power and phase of the signal transmitted by each antenna, especially under severe frequency selective fading conditions. In this paper, data spread OFDM using transmission diversity and a sub-carrier control scheme is proposed. Computer simulation of the proposed scheme demonstrated that it performs is well.

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In OFDM transmission, a loss of sub-carrier orthogonality due to Doppler-spread of the channel leads to a performance degradation caused by inter-carrier interference (ICI), especially, in mobile reception environments. To overcome this problem, an ICI canceller is very effective. This paper proposes a scheme that improves the performance of the ICI canceller that we have proposed elsewhere. The accuracy of the channel estimation is improved by reducing the influence of ICI. Consequently, the performance of the ICI canceller is improved to nearly an ideal level.

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Program targeting is being considered as a promised application in the coming PDR-based broadcasting services. However, to reflect user preference perfectly in the program selection process when using only program metadata is difficult, and to respect the intentions of service providers and broadcasters in providing programs is also difficult. Therefore, to solve this problem, we propose a program-viewing control system, in which metadata control is linked with viewers program-viewing history in a way that is easy to implement. Moreover, this system supports more sophisticated program targeting, called program substitution. The details of the proposed program-viewing control system and the metadata used are described in this paper. A comparison of the proposed system with other existing similar systems and methods proves that the proposed method is more effective and beneficial.

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To receive terrestrial digital broadcasting signals in an automobile, we previously proposed a method for controling the antenna directional pattern and demonstrated the effectiveness of the method by field experiment in an urban area. We have now investigated the reception quality during high-speed traveling and clarified the performance of doppler-shift compensation in the proposed method. A field experiment demonstrated that high-definition television (HDTV) signals can be received in an automobile traveling at about 100 km an hour.

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License plate recognition is very important technology for regulating an automobile society. However, doing so it is very difficult, because a background and a car surface color can be similar to that of the license plate. Furthermore, detecting license plates when cars are moving at a very high speed is difficult. In this paper, We propose a new method of extracting car license plates automatically by using a real-coded genetic algorithm (RGA). Using the proposed RGA, the most likely plate colors can be detected under various light conditions. First, the average brightness Y value of images are calculated. Next, the retation between the Y value and the most likely plate color thresholds upper and lower bounds are obtained with the RGA to estimate threshold equations. To prove the effectiveness of the proposed method, we describe simulations performed using real images.

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This paper proposes a “non-contact virtual clay modeling system.” We developed a prototype of a three-dimensional modeling system that allows users to shape “virtual clay” with their hand movements. In our proposed method, the users hand movements are observed with multiple cameras to estimate their positions. The human hand surface and the virtual clay are modeled by using subdivision surface. Using the estimated hand posisions, the virtual clay is shaped based on a direct free-form deformation technique. To achieve faster processing speed, we implemented the proposed system on a PC cluster. This implemented system proves the feasibility of an intuitive virtual clay modeling system.

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A variable-sensitivity image sensor aims at linear dynamic range expansion of conventional image sensors by adopting an area-based sensitivity adjustment of the focal plane. By using 0.6 μ m-CMOS technology, we made the first prototype of a variable sensitivity image sensor. The sensor can change the photo response by 6dB for row direction only. In addition, we took a picture of a scene for which setting appropriate exposure with conventional frame-based sensitivity adjustment methods is difficult. By using the row-based sensitivity adjustment method of the prototype imaging system with a variable-sensitivity sensor chip, captureing the image was easier.

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In this paper, we propose a method for compressing the data of multiple-view movie considering redundancy of the viewpoints. This is achieved by dividing multiple-view movies of dynamic scenes captured by several cameras into foreground and background, and applying projective geometry to the viewpoints for each region. Specifically, a viewpoint, called the base viewpoint of compression, is selected from multiple viewpoints and another viewpoint, called the target viewpoint of compression, is predicted by applying projective geometry between the base viewpoint and the target viewpoint. We also propose a method to decide the optimal viewpoint for compressing multiple-view movies efficiently. The results of compressed multiple-view movies and obtaining an optimal viewpoint for compressing them are evaluated in experiments.

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This paper describes a peak power reduction method that selects the data of idle code to minimize the peak power of multicarrier CDMA (MC-CDMA) systems. The method has the advantage that the side information does not have to be transmitted to the receiver side. Therefore, the receiver does not have to perform any special operations and its complexity can be reduced.

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A display system that does not require viewers to wear special glasses to see 3D images is useful technology. Conventional lenticular and parallax-barrier display systems have disadvantages in that images have divided horizontal resolution. We describe a thin stereoscopic 3D display with a parallax polarizer barrier. The advantage of the parallax polarizer barrier is that the resolution of presented parallax images is much greater than that possible with conventional displays. This compact display has two LCD panels to present stereo views and control polarization. It has twice the 3D image resolution, because the LCD image plane can multiplex images with horizontal and vertical polarization to display stereo views.

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Computer-generated pictures would be powerful aids for TV viewers to enjoy golf programs. Especially, CG pictures about ball locations are desirable. Using object extraction and tracking technologies, we have developed several new visual effects for sportscasts. The paper describes a technique of extracting and tracking fast moving objects. It also describes a technique for combining processors for motion tracking and real time CG rendering. We report the use of CG effects for golf scenes generated by our proposed system.

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