ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
Search
Advanced search
OR
Browse
Search
38.30
Displaying 1-15 of 15 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
  • [title in Japanese]
    Article type: Cover
    Pages Cover1-
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_Cover1
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (10K)
  • [title in Japanese]
    Article type: Index
    Pages Toc1-
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_Toc1
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (42K)
  • Comparison of Parallel Processing of Automatic and Optimal Design Methods Based on the Genetic Algorithms
    Hajime OTANI, Shouichi YAMAGUTI, Yuji MAEDA, Manabu OMIYA
    Article type: Article
    Session ID: BCT2014-62
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_1
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    Evolutionary computing such as generic algorithms becomes widespread for automatic and optimal designs. It finds sub-optimal parameters within the electromagnetic numerical simulations. Its amount of calculation is several % to about 10% compared with that of full parameter search. Generally speed-up by parallel processing is essentially required in the evolutionary computation because it takes long time to evaluate the fitness. Therefore, we try to achieve an elapsed time reduction for both of evolutionary computations and numerical simulations employing a parallel processing technique. At first we propose to parallelize the parameter free GA and micro GA algorithms as an evolutional algorithm. Discussing their speed-up ratios by parallel processing, the algorithm suited for parallelization will be determined. Here the numerical electromagnetic simulations are examined for the automatic and optimal design of dichroic filter structures.
    View full abstract
    Download PDF (623K)
  • Indoor Radio Wave Propagation Channel Modeling for a 5 GHz-Band Wireless LAN System
    Shouichi YAMAGUCHI, Satoshi YONEZAWA, Manabu OMIYA
    Article type: Article
    Session ID: BCT2014-63
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_5
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    It is essential to understand radio wave propagation for the efficient operation of mobile communication systems including wireless local area network system. Conventionally experiments and measurements have been carried out to estimate characteristics of radio wave propagation. On the other hand, due to the development of high-speed and large-scale computer system, numerical simulations can support characterizations of the indoor radio wave propagation in office environments and lead to many new discoveries related to them. This paper employs the large-scale numerical simulations to estimate propagation channels of the 5 GHz-band wireless LAN system as one of indoor propagation characteristics. First a high-resolution numerical model is to be developed for the electromagnetic field analysis considering the reinforced concrete walls and conductive obstacles because they reflect and distort the radio wave propagation. Visualization of the Poynting vector evaluated from the steady-state electromagnetic field components is shown to be useful to estimate radio propagation channels in the office environment.
    View full abstract
    Download PDF (10934K)
  • Prototype of Dual-polarization Antenna for Satellite Broadcasting Reception
    Masafumi NAGASAKA, Susumu NAKAZAWA, Shoji TANAKA
    Article type: Article
    Session ID: BCT2014-64
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_9
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    A 12-GHz (11.7 to 12.75 GHz) band satellite service with orthogonal polarization is expected for transmission channels to deliver advanced broadcasting services such as 8K (Super Hi-Vision). A right- and left-circular polarized parabolic reflector antenna will make it possible to receive services provided over these orthogonal polarizations with a single reflector antenna. Since it is important to mitigate cross polarization interference to use these orthogonal polarizations simultaneously, there is a need to improve the cross polarization discrimination (XPD) of the dual-polarization antenna. A dual LNB (Low Noise Block Converter), which corresponds to right- and left-circular polarizations, is also required for the antenna to carry the received signals on a single cable. Therefore, we fabricated and measured a prototype of the dual-polarization receiving antenna for the 12-GHz band satellite service. The measured results showed the aperture efficiency was more than 76%, XPD was more than 26 dB and the noise figure of the LNB was less than 1 dB throughout the 12-GHz band.
    View full abstract
    Download PDF (3946K)
  • Radiation Pattern Considering Thermal Distortion of the Onboard Reflector Antenna for 21-GHz band Broadcasting Satellite
    Susumu NAKAZAWA, Masafumi NAGASAKA, Masashi KAMEI, Shoji TANAKA, Tetsu ...
    Article type: Article
    Session ID: BCT2014-65
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_13
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    For 21-GHz band satellite broadcasting system, we have proposed an array-fed reflector antenna as part of a wide band and high power transponder combining outputs of the each element through high power amplifier that is connected to the element. The proposed antenna is reconfigurable in order to exploit the satellite's limited resources, and it has the ability to control its radiation pattern as a way of fading mitigation. Now, we are developing an engineering test antenna. In this report, we evaluate the radiation pattern considering thermal distortion of the onboard reflector antenna for the 21-GHz band broadcasting satellite.
    View full abstract
    Download PDF (618K)
  • Perfomance Evaluation of Satellite Broadcasting Using SC-OFDM for 4K/8K Transmission
    Atsushi INOUE, Akira NAKAMURA, Kohei OHNO, Makoto ITAMI
    Article type: Article
    Session ID: BCT2014-66
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_17
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    Advanced wide band satellite digital broadcasting realized data transmission rate of 100[Mbps] for 4K/8K satellite TV broadcasting. Higher transmission rate is required for the further more advanced 4K/8K broadcasting services. One of the most serious problems in satellite broadcasting is nonlinear distortion. In this paper, the modulation scheme using SC-OFDM (Single Carrier-Orthogonal Frequency Division Multiplexing) is proposed to achieve higher transmission rate. As a result, the achieved transmission rate of the proposed scheme is improved partially in all coding rates under the use of 16APSK and 32 APSK when roll off factor is 0.1. On the other hand, the achieved transmission rate is degraded when roll off factor is 0.03. The proposed scheme shows possibility of improving transmission characteristics.
    View full abstract
    Download PDF (510K)
  • Evaluating the Nonlinear Characteristics of On-board TWTA for 8K UHDTV Satellite Broadcasting
    Yoshifumi MATSUSAKI, Masashi KAMEI, Shoji TANAKA, Kazuyoshi SHOGEN, Os ...
    Article type: Article
    Session ID: BCT2014-67
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_21
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    Technical requirements (specifications) for UHDTV broadcasting including 8KTV via satellite were reported by the Information and Communications Council of Japan's Ministry of Internal Affairs and Communications in March, 2014. Increase of transmission capacity per a bandwidth is achieved by the introduction of 16APSK. In the report, to reduce the deterioration of 16APSK transmission due to the nonlinear characteristics of on-board TWTA, a back-off operation is described. In this paper, by evaluating the relationship between the output back-off and the nonlinear characteristics of the reference TWTA used at the laboratory experiment in the report, the required C/N, the guidelines for determining of the operating point (output back-off) of on-board TWTA are considered.
    View full abstract
    Download PDF (443K)
  • World trend and our broadcasting system solution for 4K/8K
    Toshiyuki Ikeda, Yasuhisa Nakata, Kensuke Shimofure, Naoya Tsuji
    Article type: Article
    Session ID: BCT2014-68
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_25
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    We describe world trend and our broadcasting system solution for 4K/8K.
    View full abstract
    Download PDF (6296K)
  • Performance Evaluation of High Speed Adaptive Modulation Scheme for Bidirectional Digital FPU System
    Kazuhiko MITSUYAMA, Tomofumi KOYAMA, Fumiki UZAWA, Naohiko IAI, Katsun ...
    Article type: Article
    Session ID: BCT2014-69
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_29
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    File-based production systems are now being introduced in the television broadcast field. The present field pick-up unit (FPU), which is one of wireless links, is not suitable for transmission of file-based video materials, since the FPU is basically a simplex and fixed-rate system. We have been developing a TDD-based bidirectional digital FPU system that enables high speed wireless transmission of file-based video materials. We manufactured a bidirectional digital FPU experimental prototype equipped with the high speed adaptive modulation function, which exploits reciprocity of the radio channel between antennas in TDD systems and can adaptively change the modulation scheme in a short period less than one TDD frame length depending on the channel condition. The results in both the wired and wireless indoor transmission experiments demonstrated that the high speed adaptive modulation function implemented could greatly improve the bit error rate performance under fast fading channels.
    View full abstract
    Download PDF (679K)
  • Throughput and Delay Evaluation of Bi-directional Digital FPU System
    Tomofumi KOYAMA, Fumiki UZAWA, Kazuhiko MITSUYAMA, Naohiko IAI, Katsun ...
    Article type: Article
    Session ID: BCT2014-70
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_33
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    Recently file-based production system is getting popular. Video footage is treated as a file in the system. Though it is preferred to transfer a video file as it is on the wireless link built by FPU (Field Pick-up Unit), the conventional FPU that is a simplex and fixed-rate system cannot do it. We are developing a new TDD-based bi-directional FPU to send a video file as it is. In this report, we evaluated the performance of throughput and delay of a prototype bi-directional FPU system. As a result, our prototype system was confirmed that the throughput of file transfer is about 140 Mbps in the long distance of 50 km and the delay of live video transmission is potentially less than 2 video frames.
    View full abstract
    Download PDF (572K)
  • Frequency Spectrum Connection Method for High Time-Resolution of Delay Profile in Digital Terrestrial Television Broadcasting
    Akira NAKAMURA, Makoto ITAMI
    Article type: Article
    Session ID: BCT2014-71
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_37
    CONFERENCE PROCEEDINGS FREE ACCESS
    Show abstractHide abstract
    In Japanese digital terrestrial television broadcasting (DTTB), the analysis of multi-path is important to improve its reception characteristics. To enhance the resolution of the delay profile, connecting continuous multiple channels and the extended frequency bandwidth are effective. However, the guard band exists between each channel and the transfer function is not obtained directly. The phases of each channel are not synchronized because the each channel is broadcasted independently. In this paper, a method to connect multiple channels is proposed. Interpolation of the guard band by using the liner adaptive predictor based on the RLS (Recursive Least Square) algorithm and compensation of phase between adjacent channels are performed. As a result, it is confirmed that resolution enhancement of the delay profile is possible. It is possible to improve the time resolution of the delay profile to below 0.024[μs].
    View full abstract
    Download PDF (774K)
  • [title in Japanese]
    Article type: Appendix
    Pages App1-
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_App1
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (80K)
  • [title in Japanese]
    Article type: Appendix
    Pages App2-
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_App2
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (80K)
  • [title in Japanese]
    Article type: Appendix
    Pages App3-
    Published: July 24, 2014
    Released on J-STAGE: September 22, 2017
    DOIhttps://doi.org/10.11485/itetr.38.30.0_App3
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (80K)
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top