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Displaying 1-18 of 18 articles from this issue
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Article type: Cover
Pages Cover1-
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (10K) -
Article type: Index
Pages Toc1-
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (50K) -
Erina OGIDA, Keisuke MIYAMAE, Kenta KOGURE, Hiroki KOJIMA, Yasuhiro WA ...Article type: Article
Session ID: BCT2014-33
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe propose an optical transmission system for realizing TV live broadcast from a midget submarine in the deep sea. At first, the system transmits video signal from the submarine to a repeater through water using blue LEDs, then transmits it to a ship on the sea through an optical fiber. Tracking technology for optical beam is important, because the submarine and the repeater moves about. We devised a new method for detecting misalignment of optical beam easily by covering the surface of the repeater with retro-reflective sheet. We made a fundamental indoor experiment for examining feasibility of proposed system. Received optical power obtained at the experiment agreed with theory. More, we succeeded in improving CN ratio by combining FM signals obtained at plural optical receivers.View full abstractDownload PDF (652K) -
Takuya KUSAJIMA, Satoshi MATSUMOTO, Naoyuki AWANO, Kenji SUGIYAMAArticle type: Article
Session ID: BCT2014-34
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn re-size (scaling) of a picture, quality up processing which are called super resolution have been studied. We have discussed a method of directional adaptive processing to reduce jaggy and ringing. On the other hand, geometric image conversion such as affine transform is one of re-size processing which have different magnification scale in a pixel. However, some super resolution methods are not suitable to this processing. At first, we discuss a hybrid re-sampling which uses a high order filter and a linear interpolation to balance the spatial frequency and flexibility. Next, pre-filtering is discussed to reduce alias component in size deduction. Finally, we apply a directional adaptive processing for the geometric image conversion to reduce jaggy. As results of experiments, it was recognized that the proposed method gives better PSNR and subjective picture quality.View full abstractDownload PDF (6399K) -
Ayumu OIKE, Takuya KUSAJIMA, Naoyuki AWANO, Kenji SUGIYAMAArticle type: Article
Session ID: BCT2014-35
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSVery high resolution video system such as 4k (4096x2160) enables super close view that distance is almost same as picture height. However, very short distance causes significant different view in a picture. Therefore, uniform processing for a picture may not be always best. At first, we calculate the actual view size of a pixel depends on the pixel position in the case of a picture height distance. the coding performance is checked for the weighted picture in frequency band limitation, contrast conversion and geometric image conversion the coding performance is checked for the weighted picture in frequency band limitation, contrast conversion and geometric image conversion. 4k resolution processing is realized by 4 pattern of HDTV picture coding with H.264 and HEVC. As the results of experiments, the possibility of 10 to 25 percent bit rate reduction is recognized.View full abstractDownload PDF (5963K) -
Hirofumi TAKANO, Naoyuki AWANO, Kenji SUGIYAMAArticle type: Article
Session ID: BCT2014-36
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSA pixel (sample) of high dynamic range (HDR) image require 16 bit quantization without gamma correction. Standard formats for the broadcast are 10 bit with gamma correction, and not suitable for file storage system because of non byte alignment. To realize high versatility and utility for HDR images, we proposed the range coding with 4 byte for 4 pixels. This data is easily changeable to 16bit linear quantized pixels. In this report, we discuss the quality improvement method using adaptive range coding based on histogram of pixel value. Narrower range is applied to the dense level with keeping range number of 16. With In the case of LPSNR (local peak signal to noise ratio) which is suitable for the evaluation of HDR images, almost 1 dB SNR gain is achieved for dark images, and it is recognized that performance of proposed method is almost the same of 10bit with gamma correction.View full abstractDownload PDF (5238K) -
Hirotomo YASUI, Kohei OHNO, Makoto ITAMIArticle type: Article
Session ID: BCT2014-37
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn OFDM transmission, performance is degraded by the existence of time domain impulsive noise. Channel estimation scheme using pilot symbols in the impulse noise environment is proposed in this paper. With the increase in the number of pilot symbols used for channel estimation, the estimation accuracy is improved, but the transmission efficiency is lowered. Therefore, in order to increase the transmission efficiency, the scheme of performing channel estimation using only the pilot symbols of 1OFDM symbol is proposed in this paper. Bit error rate characteristics and estimation accuracy of channel properties were evaluated by the computer simulation using the proposed scheme.View full abstractDownload PDF (471K) -
Masahiro ENDO, Tomoaki OHTSUKI, Takeo FUJII, Osamu TAKYUArticle type: Article
Session ID: BCT2014-38
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSSpectrum leasing is one of the cognitive radio models, where a primary user leases its spectrum resources for secondray user in exchange for cooperation. In [1] cooperative communication with beamforming in spectrum leasing was proposed for primary secure communications. However, interference is caused to the primary user from secondary user with its scheme. Therefore, we focus on cooperative communications where secondary users use orthogonal beamformings which does not affect primary user in this report. By simulation, we evaluate primary secrecy capacity, primary secrecy capacity outage probability, secondary sum throughput, and primary throughput. We show that multiple secondary transmit beamformings on spectrum leasing are effective for both primary and secondary systems in terms of primary secure communications.View full abstractDownload PDF (593K) -
Satoshi NISHINO, Suguru SAITO, Masato TANIGUCHI, Hidekazu MURATAArticle type: Article
Session ID: BCT2014-39
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe consider user selection schemes for multi-user MIMO systems with linear precoding. In this work, we apply two user selection schemes based on the orthogonality between the propagation channel of users. Indoor transmission experiments are carried out under several scenarios and the performances of user selection schemes are evaluated. It is shown that the transmission performance is improved and the user selection schemes are remarkably affected by path loss between users.View full abstractDownload PDF (4618K) -
Yuma FUJIMOTO, Ryo SHINOHARA, Yuji HAYASHI, Hidekazu MURATAArticle type: Article
Session ID: BCT2014-40
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSMulti-user multiple-input multiple-output (MU-MIMO) transmission is studied to improve the spectrum efficiency in wireless communications. The performance of MU-MIMO is limited in the presence of multi-user interference. We consider the received signal sharing between mobile stations in order to equivalently increase the number of antennas. This paper proposes a collaborative interference cancellation scheme utilizing short-range wireless interface. We conduct transmission experiments in an actual indoor environment in order to evaluate the performance of the collaborative interference cancellation scheme implemented in the MU-MIMO testbed.View full abstractDownload PDF (3759K) -
Tetsuya YOSHIDA, Kazuyuki SAITO, Koichi ITO, Masaharu TAKAHASHIArticle type: Article
Session ID: BCT2014-41
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe 700 MHz band is used for the Field Pickup Unit (FPU), which used for live broadcasting, such as marathons and ekiden. However, the frequency band is planned to migrate to 1.2 and 2.3 GHz bands by the action plan for radio spectrum reallocation developed by the ministry of internal affairs and communications, Japan. As the frequency migration of FPU, the size of transmitting antennas can be downsized. Therefore, the antennas for 1.2 and 2.3 GHz also will be mounted on wireless cameras for professional-use. In this report, we measured the specific absorption rate (SAR) on the body of the operator exposed to electromagnetic waves radiated from the transmission antenna of the wireless camera by 1.2 GHz band. As the result, good agreement between measurement and calculation was observed. Therefore, it can be said that the SAR measurement technique is useful for evaluation of this kind of equipments.View full abstractDownload PDF (8081K) -
Yukihiro NISHIDAArticle type: Article
Session ID: BCT2014-42
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSStandardization of new satellite broadcasting systems are under way towards the launch of ultra high definition television (UHDTV) broadcasting including 4K and 8K. The 8K Super Hi-Vision has been developed as an ultimate form of a two-dimensional television that can provide an increased sense of presence as well as the sense of realness to viewers. The video and sound systems have been designed on the basis of the psychophysical characteristics of human beings. This paper describes the studies of 8K Super Hi-Vision, UHDTV studio standards, and the ongoing standardization of broadcasting systems.View full abstractDownload PDF (832K) -
Fumito Ito, Shinichi Suzuki, Naoto Kogo, Hiroyuki HamazumiArticle type: Article
Session ID: BCT2014-43
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe have developed a wireless camera in 42 GHz band, which can transmit Hi-definition pictures with low latency. For wider transmission ranges and higher reliability, antenna gains are improved by narrowing beam in vertical plane because vertical adjustment has relatively little importance compared with horizontal adjustment in outdoor environments, and expected area of wireless cameras is limited in indoor environments. In this paper, we applied elliptical horn antennas to this system and compared received power and CNR of these antennas with those of conventional horn antennas through outdoor and indoor experiments.View full abstractDownload PDF (8101K) -
Atsuro ICHIGAYA, Yukihiro NISHIDAArticle type: Article
Session ID: BCT2014-44
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSToward the launch of Ultra High Definition Television (4K and 8K) broadcasting, standardization of a domestic broadcasting system is under development in the Information and Communications Council and the Association of Radio Industries and Businesses (ARIB). Its video coding method will be based on the latest international video coding standard, ISO/IEC 23008-2 MPEG-H HEVC|ITU-T H.265. To show the required bit rates for the UHDTV broadcasting adopting HEVC, ARIB conducted coding experiments and subjective assessments of the coded picture quality by using multi-format test pictures of 4320/60/P, 2160/60/P, 1080/60/P and 1080/60/I. Moreover, we investigated required bit rates for coding of video with the 120 Hz frame frequency which employs the temporal hierarchy coding.View full abstractDownload PDF (9219K) -
Susumu SAITO, Takuya SHITOMI, Shingo ASAKURA, Kenichi TSUCHIDA, Tomohi ...Article type: Article
Session ID: BCT2014-45
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe are conducting research on the next generation of digital terrestrial broadcasting to enable large-volume content services such as 8K Super Hi-Vision (8K). We have installed an experimental station for 8K transmission at Hitoyoshi city, Kumamoto prefecture, Japan using dual-polarized multiple-input multiple-output (MIMO) technology and ultra-multilevel orthogonal frequency division multiplexing (OFDM) technology. In these 8K field experiments, we succeeded in carrying out the world's first 8K terrestrial transmission (91 Mbps) at long distance over 27 km using only UHF (ultra-high frequency) single channel (6 MHz). We also report the required field strength for 256QAM, 1024QAM, and 4096QAM carrier modulation scheme and the response of dual-polarized MIMO transmission channel.View full abstractDownload PDF (5987K) -
Article type: Appendix
Pages App1-
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (80K) -
Article type: Appendix
Pages App2-
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (80K) -
Article type: Appendix
Pages App3-
Published: February 13, 2014
Released on J-STAGE: September 22, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (80K)
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