JRC REVIEW No.62 Technical Reports

- Special Issues : Solution Business-

The importance of the communication of information at disaster sites continues to increase, in response to the large-scale disasters over wide areas which have been occurring frequently in recent years. For communication of information during such disasters, satellite communication systems using a transportable VSAT are an indispensable communication method. However, although the conventional transportable VSAT system is lightweight and compact, until now there have been only a compact transportable type with lower communication capacity, and a larger transportable type with a higher communication capacity which is heavy and requires time to be assembled. In order to deal with both of these weak points, we developed an intermediate communication capacity transportable VSAT with a plane antenna, which ensures substantial communication capacity even though it is compact.

Keiichi Natsuhara
Kazuhiro Ishizawa
Kiyomi Yoshida
Hiroshi Itoh
Hiroyoshi Matsudaira

- Special Issues : Solution Business-

This ultrasonic moving image filing system compresses the images and doppler sounds from the image output unit for medical use which is the best known type of ultrasonic diagnostic equipment, with an H.264 encoder, first stores the data in an SD card, and then transmits and saves the data into a hospital's image server via an IP network.

Since the images saved on a server can be accessed through mobile terminals iPhone or iPad which have become popular in recent years, as well as through image reading terminals Windows PC or Mac, images can be accessed anywhere in the hospital as required.

Images can be recorded in units of several minutes by adopting H.264 Standard encoder developed by JRC as the image compression method, which is useful in medical fields where movement needs to be observed, such as the circulatory system.

Masaharu Nakayama
Kousuke Ueda
Hitoshi Saito

- Special Issues : Solution Business-

In March 2003, an 18 GHz frequency band became available for public services which use self-managed wireless communication networks. Compared to conventional frequencies for public services, the regulations were greatly eased for this frequency band, so use of these systems rapidly expanded. In recent years, the demand for wireless systems for disaster prevention has increased, and application has become the large flexibility for the user. In order to satisfy such a market demand, JRC developed a multiplex radio communication device (including a backup system) .

Kohji Mohri
Shinya Murata
Yuichi Mita
Ryo Kukita
Hiromu Yoshie

- Special Issues : Solution Business-

A road information system provides the information required for safe management of roads, including road weather information, on road information boards etc. Since the installation of the first system in 1987, installations have increased yearly, and now systems for each main bureau and systems for offices of the Ministry of Land, Infrastructure and Transport in Tohoku, Kanto, Chubu, Kyushu and Okinawa have been installed. In the beginning, the systems were constructed with custom equipment developed by JRC, and performance and function of the systems have continually been improved over the years. We have been providing information not only to road managers but also to general road users through the internet, and setting up automated provision of information activated by guidance system. This report indicates the technology trends of the road information systems developed by JRC, and describes the future outlook for these systems.

Naoshi Naitoh
Masao Takeda

- Special Issues : Solution Business-

The third generation dam control system for Chubu Electric Power Co., Inc. performs remote monitoring and control of the major dams of this company. The main purpose of this system is to make dam operations more efficient, while achieving great improvements in safety and reliability. This system is substantially different from conventional dam control systems.

JRC has participated in the third generation dam control system from the designing stages, and has been able to install this system for 2dam management groups (controlling a total of 10dams) . This report describes the features of the third generation dam control system, and the points of difference from a conventional dam control system.

Shoji Hamazaki
Kazunari Mizukami
Susumu Naitoh
Masaaki Motohashi
Tomoaki Endoh
Hisaki Fujimoto

- Special Issues : Solution Business-

In recent years, there have been human casualties due to sudden rising water in urban areas etc. caused by localized torrential rains. Therefore, reduction in the time required by telemetry observation systems for detection and warning transmission has become a pressing technical issue. The Ministry of Land, Infrastructure and Transport established new standard specifications for telemetry equipment in July 2011 (MLIT Telemetry Equipment Standard Specification No.54) . These standard specifications enable quick collection and distribution of observation data, using a method (time slot transmission method) that acts autonomously to transmit data from an observation station. JRC has developed autonomous telemetry equipment which meets these standard specifications and has exclusive and superior features, and introduced it into the market in fiscal 2011. This report introduces the features of the autonomous telemetry equipment developed by JRC and tools to verify the installation site conditions.

Tatsuji Fujise
Yasushi Watanabe
Jun Satoh
Tsutomu Takahashi
Ryo Nakahara

- Special Issues : Solution Business-

In recent years, the digital pre-distortion (DPD) method has begun to spread for distortion compensation of power amplifiers in transmitters which transmit digital modulation signals.

There are several distortion compensation methods in high power SSB transmitters for HF bands; however, the amount of compensation in the analog method has reached its limit. We have realized commercialization by adopting DPD for the first time, in the latest transmitter we have developed.

This report introduces the development history, features, unique technology etc. of this transmitter.

Tsuyoshi Satoh
Takafumi Nojima
Koichi Hasegawa
Noriyuki Ichihashi
Koichi Nakahara

- Special Issues : Solution Business-

In recent years, the importance of meteorological radar has been rapidly increasing in order to always keep inhabited areas safe from local torrential rains, local down pours and urban type tornados which are occurring because of rapid climatic changes.

Most meteorological radar systems are installed in sites with unfavorable geography and climate, and in order to guarantee stable operation even under such conditions, there is increasing demand that meteorological radar use solid state components instead of the currently used klystrons and magnetrons which have short lives and require maintenance and inspections. Therefore, the S band solid state meteorological radar developed by JRC is here introduced as an example of a desirable system.

The system was installed and evaluated at actual sites, it was confirmed that the performance was not inferior to conventional meteorological radar, and actual operation has commenced.

Hiroshi Suenaga
Hideki Tamura
Yukihiko Nakagawa
Yuya Nokiba
Yutaka Ishiuchi

- Special Issues : Solution Business-

The digitalization of terrestrial TV broadcasting was completed on July 24, 2011. As a broadcasting equipment manufacturer, JRC participated in the infrastructure construction for terrestrial digital TV broadcasting, by providing various products. Particularly, we believe that JRC greatly contributed to the infrastructure of the digitalization in the field of relay broadcasting systems, which JRC has excelled in from the times of analog broadcasting. This report describes the transitions in the products developed and released by JRC.

Kenichi Kohno
Satoru Akahori
Kazushige Karasawa
Hidetaka Takashina
Hiroyuki Kimura
Kiichi Kaji
Tadayuki Kitamura
Mitsuhiro Nishiguchi
Satoshi Ono
Toru Taya