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Yoshinori Yuki, Katsuyuki Shinohara, Toshi Minami
Article type: Article
Pages
195-196
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Recently, to increase the security, various personal identification methods using features of living human body have been studied. In this paper, we consider a personal identification method using local characters of Ear images and show the characterization of Ear images using the maximun eigen value of the K-L expansion of morphological pattern spectra obtained from opening and closing operations.
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Takashi SAKUSABE, Yuji KIUCHI
Article type: Article
Pages
197-198
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A method for personal identification considering probabilities of measured definite line features of facial TV images has been tried. As a result, 100% recognition rates are obtained for both 10 registered samples and 150 unknown samples.
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Y. Onodera, F. Takahashi, H. Yokouchi
Article type: Article
Pages
199-200
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Dynamic focusing method has been evaluated for 2000-scaning-line SATICON television camera for high-resolution real-time digital radiography. Horizontal spatial resolution was remarkably improved, though it was lower than vertical one. Dynamic focusign should be applied to optimize the horizontal spatial resolution at peripheral view field.
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Takahiro Yamaguchi, Hiroshi Fukagawa, Yoichi Suzuki, Shin Hasegawa, Ka ...
Article type: Article
Pages
201-202
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Two X-ray images, one taken by higher photon energy X-ray and the other taken by lower one, were recorded on laser videodisc. Then they were computer-processed in order to improve the image quality. From a medical point of view, by the use of a noise reduction method-median filtering, less noisy and fairly good images of the canine coronary arteries were obtained.
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Kazuya Matsumoto, Masanori Matsubara, Shin Hasegawa
Article type: Article
Pages
203-204
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The use of stereoscopic angio images was made to detect the depth of vessels. Skeltons of pairs of vessels were extracted whose coodinates were applied to the triangulation method to calculate the depth. Profiles of the X-ray images were measured to investigate the errors of the depth caused by skelton techniques.
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Kenji noda, Shigeri Inui, Hiroaki Yamada
Article type: Article
Pages
205-206
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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T. Fujita, T. Ikeguchi, T. Matozaki
Article type: Article
Pages
207-208
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We modify the automatic extraction scheme of brain tissue from MRI with template matching. We calculate the local fractal dimension as a complexity parameter and vary the size of template which is propotional to the fractal dimension. As a result, the extracted brain shape looks better with the modified method.
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M. Takesima, T. Ikeguchi, T. Matozaki
Article type: Article
Pages
209-210
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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In this paper, we estimate the fractal dimension of the model (Koch curve and Sierpinsky gasket) which have self-similarity, with the modified method which can reduce the estimation errors due to the location of the objects. And as an application of this estimation to the MRI, we evaluate the complexity of brain contour properties.
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Hiroyuki HAMADA, Kyoichi SAITO, Seiichi NAMBA
Article type: Article
Pages
211-212
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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An objective picture quality scale for television pictures is studied. The scale derived from the weighted SNR by three dimensional human visual characteristics and the experimentally obtained subjective picture quality show a good coincidence. Furthermore, the relationship between the temporal change of picture quality and the subjective assessment of picture quality is investigated.
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Hideo Yamauchi, Joji Urano, Hironao Sakaguchi, Yasuo Yoshizawa
Article type: Article
Pages
213-214
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This paper describes a study of a codec for non-interlaced 525-line(525/1 : 1) signals. We estimated the relationship between bit rate and picture quality, using an experimental codec model by computer simulation and 525/1 : 1 test sequences prepared for this research. The results verify the feasibility of a 525/1 : 1 codec providing primary-distribution picture quality using picture rate of 30 to 45 Mbps.
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Takahiro HAMADA, Shigeyuki SAKAZAWA, Ryoichi KAWADA, Shuichi MATSUMOTO
Article type: Article
Pages
215-216
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Component TV signal-based interframe MC DCT scheme is widely used because of its high performance. Current TV transmission, however, is conducted at composite TV signal base. Y/C separation, therefore, is needed to apply interframe MC DCT scheme to composite TV signal. But this causes degradation in picture quality and additional hardwares. We, thus, propose composite TV signal-based interframe MC scheme using Hadamard transform (WHT) to avoid Y/C separation. In this scheme, colour sub-carrier phase is compensated on WHT domain according to a motion vector, and MC with more than half pel accuracy is performed by interpolation of WHT coefficients. Coding performance of this scheme is evaluated by computer simulation.
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Shigeyuki SAKAZAWA, Takahiro HAMADA, Shuichi MATSUMOTO
Article type: Article
Pages
217-218
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We are studying a probability of 2 programs of EDTV2 transmission via 27MHz or 36MHz bandwidth transponder by "MUCCS45" (45Mbps multi-channel TV coding system) In order to realize the transmission, a new quantizer suitable to EDTV2 characteristics is designed with a theoretical optimization for a video signal and a supplemental signal. As a result, 1〜3.5[dB] in SNR can be gained in computer simulations.
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Jeong Su Lee, Yoshiyuki Yashima
Article type: Article
Pages
219-220
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A reduction method for in-band noise of HDTV is proposed and simulated. The threshold of dead-zone which is excluded from image spectrum is adaptively decided from the average power of 8x8 block based image itself. The simulation results show obvious reduction of noise without degradation of the image itself.
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Hiroshi GUNJI, Akiko GONDA, Hitoaki OWASHI
Article type: Article
Pages
221-222
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Picture quality of cascade coded/decoded image is evaluated. Computer simulations using a JPEG-based HDTV coding show that the decoded picture quality is degraded when block boundary is shifted from the previous location. We considered an effective method of compensating the shifting in order to avoid the picture degradation.
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Shigeo Fujishiro, Masayuki Aiba, Nobuyuki Sadanaka, Kazuyuki Takahashi
Article type: Article
Pages
223-224
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We have developed HDTV video codec based on MPEG2 for transmitting. This system is compresses HDTV digital studio signal into about 30Mbps.
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YUJI NOJIRI, IWAO OBATA, YUKIO SUGIURA, JUNJI KUMADA, FUMIO OKANO, YAS ...
Article type: Article
Pages
225-226
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We have developed HDTV standards converter for experiment. It can convert 1125/60/2 : 1 signals into 1250/50/2 : 1 signals, and vice verse. The standards converter is composed of a motion detector, a motion vector detector, motion compensated field rate converter and motion adaptive line rate converter. We give an outline of it in here.
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Hajime Sonehara, Yuji Nojiri, Hiroshi Hirabayashi
Article type: Article
Pages
227-228
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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NHK has developed an HDTV Standards Converter bidirectional between 1125/60/2 : 1 and 1250/50/2 : 1. Motion compensating methods for HDTV standards converter between 60Hz and 50Hz field rate are necessary as well, in order to use the advantages of the increased temporal resolution and to avoid motion judder and motion blur. Inaccurate motion detection and inaccurate motion assignment has to be taken into account in order to avoid additional artefacts. This paper describes the simulations and the hardware design used algorithm of motion compensation which is considered spatial and temporal motion vector flow.
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Hiroshi Hirabayashi
Article type: Article
Pages
229-230
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A slow motion picture is used often in sports programs and other programs in general. In order to reproduce a picture which has a smooth movement with high clarity, high speed camera is usually required. If a slow motion picture is generated by using image processing system (post-production) after shooting a picture with a conventional camera which is readily available, a slow motion picture will be widely used. In this paper, the study and result of generation of slow motion picture using computer simulation system is described.
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Yasuaki Kanatsugu, Junji Kumada
Article type: Article
Pages
231-232
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Conversion between the signal sets of GBR and YC may often introduces errors in the converted signals, when digital matrices are used. This is due to the finite bit-length of the matrix coefficients and the rounding of the converted signal to a finite bit-length. The paper presents a derivation method in which teh error-free digital matrices are obtained, as well as an example of such matrices for the CCIR Rec. 709 colorimetry.
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Akihiro Hori, Masakatsu Tanaka, Tadao Kurosaki
Article type: Article
Pages
233-234
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The new component concept for the progressive scanning systems proposed based on the CCIR recommendation 601 "422". They are : 1) 422+4 (supplemental progressive information "4") 2) 422+2 (supplemental progressive information "2") 3) 4112 (supplemental progressive information "2", chroma information "1") These systems are applicable to the second generation EDTV and the other media such as HDTV.
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Koichi SATO, Seijiro YASUKI, Yasuo TAKAHASHI, Hisakatu ITO, Tetuya KAI ...
Article type: Article
Pages
235-236
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A newly developed letterbox processing techique is presented. Temporal high and temporal low components decomposed from original wide screen TV signal are separately encoded based on 525/1 : 1/30 [Hz] signal format. This technique can convert both progressive and interlace scan signal to letterbox form signal which is compatible with existing TV receivers.
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Masahiro KAGEYAMA
Article type: Article
Pages
237-238
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This paper presents a new coring scheme for noise reduction, which can be applied to all Vertical-Temporal (VT) helper signals at EDTV-II receivers. A conventional one is directly operated to the VT signal, and a flicker takes place even in still areas in case of a Line-Difference (LD) method. The proposed one is operated to a reproduced proscaned signal. That results in no flicker disturbance.
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Norihiro Suzuki, Masahiro Kageyama, Hiroshi Yoshigi, Takahiko Fukinuki
Article type: Article
Pages
239-240
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This paper proposes a method reducing the visibility of VT (Vertical-Temporal) helper signals multiplexed in top and bottom bars on EDTV. In the method, a progressively-scanned signal is pre-filtered in the vertical-temporal frequency domain, then the VT signal is produced. The energy of the VT signal decreases. Therefore its visibility can be reduced. The pre-filter characteristics need not be regulated, and the pre-filter can be discarded after EDTV receivers become popular.
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Y. Hirose, K. Setoh, S. Nakai, Y. Yasumoto, T. Yoshida
Article type: Article
Pages
241-242
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This paper describes a generating method of a LD-signal for EDTV. An original LD-signal (180 line/field) is limited to 120 TVL and converted to 120 lines per field. Moreover, we can use QAM to transmit this converted LD signal, and reduce an interference to a conventional TV set.
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Kenichiro Hayashi, Tadahiro Yoshida, Yoshio Yasumoto
Article type: Article
Pages
243-244
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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FDM(Frequency Division Multiplex) of VT(Vertical-Temporal high frequency component) signal and VH(Vertical High frequency component) signal for EDTV is described. The FDM is realized by limitting the VT and VH signals in the Vertical-Temporal frequency domain. This method enables us to transmit both VT and VH signals all the time.
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Hideyo Uwabata, Sadashi Kageyama, Takaya Hayashi, Tsutomu Noda, Takato ...
Article type: Article
Pages
245-246
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A digital data transmission system compatible with NTSC was evaluated using a conventional TV transmitter. It uses QAM of a video carrier. The influence of nonlinear distortion caused by the high power transmitter was examined. The experimental results proved 10^<-3> BER can be obtained with 4 degree ICPM and 30dB video S/N condition.
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Takatoshi Shirosugi, Tsutomu Noda, Kiyoshi Sunagawa
Article type: Article
Pages
247-248
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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A digital audio signal transmission system that uses quadrature amplitude modulation for the video carrier is examined. In this paper, the authors describes the eye pattern characteristics derived from computer simulation study using a model of ICPM of TV transmitter. The resultant characteristics of eye patterns well coincided with experimental data.
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Yasuhiro YOSHIOKA, Akira NISHIGORI, Haruo SAKATA
Article type: Article
Pages
249-250
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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It is necessary to reduce the noise of a receiver to extend a stereo reception area under FM stereo broadcasting system. We have developed a receiver of improved FM stereo S/N performance at the low field strength by using of a correlation between the frequency of main signal and that of sub signal.
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Masayuki TAKADA, Kenichi TSUCHIDA, Tadashi ISOBE
Article type: Article
Pages
251-252
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This paper describes a comparison of page error rates between two packet structures of FM multiplex broadcasting for mobile reception. As a result of calculation and simulation using error pattern data collected in a FM service area, a packet structure which can be absolutely identified as the packet is suitable for this system.
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KOJI SASANO
Article type: Article
Pages
253-254
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This is a field measurement result by ROD ANTENNA for the purpose of TV-DATA-BROADCASTING, receiving the FAX-BROADCASTING-SIGNAL/MPX-ON-AUDIO which has been adopted to TV standard.
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Yasuhiro Hashimoto, Hiroki Nakamura, Kenji Ueoka, Toshio Aoki, Yuichi ...
Article type: Article
Pages
255-256
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We make up the digital VSB modulator which generates television RF video signal. VSB filter is realized equivalently in base band complex video signal to avoid circuit complexity.
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Hiroyuki HAMAZUMI, Yasuhiro ITO, Hiroshi MIYAZAWA
Article type: Article
Pages
257-258
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Adaptive Weighted Code Division Multiplexing (AW-CDM) transmission system can achieve a graceful degradation of TV service by dividing the hierarchical information into spread-spectrum subchannels, each of which has a different priority and therefore a different threshold. Hardware of AW-CDM system shows an excellent performance under severe propagational conditions.
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Tetsuomi IKEDA, Yuichi IWADATE
Article type: Article
Pages
259-260
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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In the digital transmission of high bit rate Hi-Vision signals, it is necessary to have a high efficiency multilevel digital modulation. NHK has developed a test set of 59.94Mbps multilevel QAM MODEM for a microwave link and coaxial CATV. This paper especially describes a pilot carrier injection method for easy carrier recovery.
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Shigeki Moriyama, Masafumi Saito
Article type: Article
Pages
261-262
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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An experimental OFDM modem has been developed to study digital transmission characteristics. Results of indoor experiment confirm that QPSK-OFDM system is superior to single-carrier QPSK system in the presence of ghost signal, and necessary linearity of amplifier used in the OFDM scheme is more than 20 dB in terms of third-order intermoduration product.
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Atsushi Ishiyama, Yoshiko Watanabe, Terumasa Tokumoto
Article type: Article
Pages
263-264
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Hi-Vision is broadcasted via DBS in FM. To examine RF transmission characteristics between receiving antenna and a DBS receiver, it's convenient if we could estimate it from demodulated MUSE baseband signal response. However, it usually has difficulties due to the non-linear distortion caused by phase distortion in RF stage. This paper contains the result of transmission experiments of MUSE-FM signal and clarifies the applicable baseband distortion range within which we can reliably estimate the reflection characteristics of RF transmission line.
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C. OHUCHI, K. KAMEDA, T. OSHIMA, K. OSHIDA, H. MORIKAWA, H. FUKUCHI, A ...
Article type: Article
Pages
265-266
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The Communications and Broadcasting Engineering Test Satellite (COMETS) is planed to launch in February 1997. This paper gives the design performance of COMETS advanced satellite broadcasting mission in 21GHz band. The characteristics of transponder such as multi-beam antenna with beam pointing mechanism and high power TWT amplifier are described.
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Hajime Fukuchi, Aiichiro Tsuzuku
Article type: Article
Pages
267-268
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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In order to establish 21GHz band satellite broadcasting system, it is important to estimate the effect of rain attenuation, on the system performance. Rain attenuation contour map over Japan at cumulative time percentage of 0.3% in the worst month, which is proposed as a candidate for service availability criterion, is derived from rain rate statistics. So far, several mitigation methods of attenuation effect have been proposed. Features of these methods are compared and, as one example, improvement expected from "time diversity" method is shown.
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Aiichiro Tsuzuku, Hajime Fukuchi
Article type: Article
Pages
269-270
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The Communications Research Laboratory (CRL) has been studying an advanced satellite broadcasting system that uses the K-band such as 21 GHz band. The satellite broadcasting in 21 GHz band has much degradation due to rain compared with that in 12 GHz band. Therefore, we propose the hierarchical modulation to realize the "graceful degradation" by controlling the Euclidean distance of the symbol. This report describes the BER characteristics derived from theoretical analysis, and improvement of the frequency utilization efficiency.
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Hiroki Ohta, Mitsugu Ohkawa, Aiichiro Tsuzuku, Hajime Fukuchi
Article type: Article
Pages
271-272
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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We studied dual-polarization frequency reuse channels for 21GHz band satellite broadcasting system. In order to evaluate the effects of attenuation and XPD, simulation of QPSK co-channel interference is done. Bit-error rate statistics for single and dual polarization channels are derived from simulated results and attenuation statistics. As a result, effect of XPD is not significant.
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Mitsugu Ohkawa, Hiroki Ohta, Aiichiro Tsuzuku, Hajime Fukuchi
Article type: Article
Pages
273-274
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Currently, the broadband FM is used for satellite broadcasting system in the 12 GHz band. For future 21 GHz band broadcasting systems, digital broadcasting will be expected because of the higher flexibility and compatibility with other digital media. The information bit rate will increase according to requirement of definition and channels. The 21 GHz band satellite broadcasting has degradation of performance due to rain. Therefore, we need to adopt modulation methods that has advantage to noise and efficiency of frequency bands. This paper describes consideration of QPSK using the convolutional coding and the trellis coded 8 PSK for digital satellite broadcasting system in 21 GHz band.
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Kouji OHSAKI, Naoki KAWAI, Akira OHYA
Article type: Article
Pages
275-276
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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ISDB provides a variety of digital services and is transmitted over different kinds of transmission channel. This paper describes a layered model for the ISDB system based on the OSI reference model. The use of this model facilitates smooth construction of interoperable digital broadcasting systems.
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Takeshi KIMURA, Kouji OHSAKI, Naoki KAWAI
Article type: Article
Pages
277-278
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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ISDB broadcasts a variety of services including multi-media ones. Therefore, it uses a transmission signal format based on a packet multiplexing method. This paper describes data access schemes which enable an ISDB receiver to select and get desired program data from the ISDB transmission signal.
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Toshiro YOSHIMURA, Kazuya USUI, Tadashi ISOBE
Article type: Article
Pages
279-280
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Multi-channel digital television system is the first step for establishing ISDB system. New extended functions for television services, such as electric program guide and additional data services, should be implemented into digital system. Experimental system has been developed to simulate the functions. This paper reports the functions, the concept for specifications and the developed experimental equipment.
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Kazuya USUI, Toshiro YOSHIMURA, Tadashi ISOBE
Article type: Article
Pages
281-282
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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It is necessary for the future digital TV system to supply the easy and familiar way of program access. Signals for supplementary services will be transmitted with digital TV signal to make program access easy for viewers. This paper reports the problems of the existing access method, a new access method so that the program can be selected according to their type and its experimental system.
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Kun Ji, K. Sawada, T. Ando
Article type: Article
Pages
283-284
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The field emitter giometry for the image device was studied. The creater type field emitter was investigated in order to get high current density, because the current density of 1μA/pixel is needed for image device. It was found that the current density of the creater type was a hundred times higher than that of the cone type.
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K. Nagatsuma, K. Tsuji, T. Makishima, K. Sameshima, T. Hirai, H. Maruy ...
Article type: Article
Pages
285-286
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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An Avalanche-type X-ray Image Pickup Tube with an amorphous selenium (a-Se) photoconductive layer is investigated. The sensitivity is improved to realise in-situ X-ray photon counting operation by using a thick a-Se layer (25μm) and a BN face plate, and by adopting an electrode for high voltage operation.
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Yoshiro Takiguchi, Tsutomu Kato, Shiro Suzuki, Kenkichi Tanioka, Tadaa ...
Article type: Article
Pages
287-288
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Generally, in the out of beam scanning area in the target of a camera tube, the surface potential of the target increases to almost the same voltage applied to the target. In the case of the Super-HARP tube, this phenomenon influences the beam landing characteristics and sometimes causes spurious images on the edge of the picture because of the very high voltage applied to the target. In order to decrease the surface potential, a new target structure has been developed, which has very little sensitivity. It is confirmed that the spurious images can be eliminated by applying this structure to the outside of the beam scanning area.
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J. Yamazaki, H. Maruyama, M. Kubota, T. Yamagishi, T. Kikkawa, T. Suga ...
Article type: Article
Pages
289-290
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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This study investigated ways to obtain high SNR pictures at very low light intensities with a HARP camera. It confirmed that intermittent read-out of the HARP tube is the most suitable method for shooting objects in slight motion concluding that NTSC and HDTV HARP cameras which use this technology could even shoot the tale of a comet and a faint aurora with clear images.
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Shinya Akata, Chihiro Mochizuki, kazuaki Sawada, Takao Ando
Article type: Article
Pages
291-292
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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Photocurrent characteristics of a-Si : H/a-SiC : H graded-superlattice structure photodiode film were investigated. It was experimentally confirmed that the quantum efficiency of this photodiode exceeds unity, because of an enhancement of an ionization rate by conduction bandedge discontinuitys.
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Y. Sugie, H. Ono, T. Ozaki
Article type: Article
Pages
293-294
Published: July 27, 1993
Released on J-STAGE: October 02, 2017
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The breakdown current of the vertical CCD isolated by the shallow p+ layer was analyzed. The strong electric field at the surface of the channel, between the adjcent gate electrodes and between the channel and the p+ layer causes the current. The breakdown current is reduced by reduction of the pinning voltage and usage of longer distance between the channel and the p+ layer.
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