JRC REVIEW No.61 Technical Reports

- Special Issues 1 : Communications Networks Equipment -

The digital optical repeater for the mobile communication system is the equipment to improve the communication quality at the area where is not covered by the mobile communication BTS. JRC has developed mainly analog optical repeaters.

This time we developed the digital optical repeater by adopting the high efficiency DPD amplifier and digital optical communication technologies in order to fulfill market requirements of smaller size, lighter weight, lower cost, and availability on the low speed optical transmission line (dark fiber, etc) . The newly developed repeater has the tolerant optical transmission loss of 20dB and the tolerant return loss of 22dB, and achieves the small size of the 14.9 liter volume and the weight ≤12 kg. These are corresponding to 52% reduction of the volume and weight respectively at the comparison with the existing analog optical repeater.

Masatoyo Nishibe
Akira Tago
Norihisa Kawasumi
Wataru Soyama
Toshiyuki Aoki

- Special Issues 1 : Communications Networks Equipment -

Recently, the market pressure towards higher efficiency, smaller size, and lower cost is getting more severe for cellular phone base station equipment. In response to this, JRC has developed the high efficiency DPD Amplifier with a multitechnology feature for the transmitting amplifier which occupies a large part of the cellular phone base station. This amplifier employs the Doherty circuit to achieve high efficiency. The DPD optimized for this amplifier is developed to comply with spurious emission requirements. The achieved high efficiency makes downsizing and cost reduction possible.

Akira Yamada
Hirohisa Hirayama
Takaaki Ishikawa
Yoshitomo Miyatake
Takashi Watanabe

- Special Issues 1 : Communications Networks Equipment -

With the recent progress of NGN (Next Generation Network) deployment and market demands for advanced services based on it, Fixed Wireless Access (FWA) System is also required to suppor t triple play ser vices of voice, video distribution, and internet access.

Data traffic explosion in mobile radio access network due to the widespread use of smart-phone urgently demands effective backhaul solutions for micro/pico cellular base stations.

In order to meet these market requirements, JRC has developed 26GHz FWA equipment called as "New WIPAS (Wireless IP Access System) " supporting high-speed data communication of P-P (Point to Point) which use quasi-millimeter wave. This equipment is the TDD system with flexible downlink and uplink ratio and achieves maximum 192 Mbps aggregated data throughput. It also supports adaptive modulation among QPSK, 16QAM and 64QAM and QoS control with 8 priority classes to improve the link quality and availability.

True zero-footprint (all in one) mechanical structures of the equipment contribute to minimize total cost of ownership of the network.

Kazuo Saitoh
Kiyohito Kobayashi
Takeshi Gomi
Shinji Nagamine
Shinya Yoneda
Hitoshi Nagahori
Masato Nishibori

- Special Issues 1 : Communications Networks Equipment -

JRC has been providing the total WiMAX solutions comprising the base station, subscriber management system, base station management system and mobile station for the regional mobile WiMAX operators. This report introduces the multicast features newly added to the current systems, enabling simultaneous content distribution service. The multicast function will make effective use of radio bandwidth of regional WiMAX and allow the operators to deploy more advanced application such as local broadcast service.

Katsuhiko Sato
Sadayuki Katsumata
Akira Hasegawa
Kazuhiro Terayama
Norifumi Yoshida

- Special Issues 1 : Communications Networks Equipment -

The roaming function among operators allows subscribers to receive services from their operator by use of other affiliated operator's infrastructure. This article reports JRC has developed the roaming features on its WiMAX system and established system architecture of the user authentication, QoS authorization, IP address allocation and accounting functions under the roaming. Collaborating regional WiMAX operators, subscribers can receive more enhanced the convenience of their WiMAX service.

Takeo Kimura
Yasushi Suzuki
Koichi Yagishita

- Special Issues 2 : Communication Equipment -

Vehicle safety communication system in 700MHz-band that broadcast drive-assist information and call the driver's attention by wireless telecommunication is expected to have an effect for prevention of traffic accidents.

Vehicle equipments in the system exchange drive assist information by Road-to-Vehicle Communication (RVC) that communicates between an on-board equipment and road-side equipment, and by Inter-Vehicle Communication (IVC) that communicates between vehicles. 700MHz-band is going to be allocated for the system in 2012 when the terrestrial analog broadcasting end.

JRC has developed on-board equipment that is operated in 700MHz band for the Vehicle safety communication system, and this paper introduces it.

Akira Takai
Yasushi Koyama
Kouji Kashima
Masaaki Matsumura
Masayuki Takahashi
Shigeyuki Asami
Yuji Igarashi

- Special Issues 2 : Communication Equipment -

This paper outlines the GPS receiver developed by JRC. A custom IC which integrates in one chip most of the circuits required for the GPS receiver was developed, and is also introduced in this report. The GPS receiver developed by JRC is not only for car and ship navigation which was the original application, but is also equipped with functions allowing its use in mobile devices, digital cameras, etc. These functions have been evaluated highly. The GPS receiver is also equipped with hardware to support the "Galileo" and "QZSS" GNSS.

Yasunori Aiga
Hisayoshi Ishiguro
Tatsuya Suzuki

Koichi Washizu
Masahiro Genda

- Special Issues 2 : Communication Equipment -

This module is a WiMAX communication module for industrial devices, that conforms to the mobile WiMAX specifications (IEEE802.16e-2005) .

In contrast to conventional products, the operating temperature range was expanded to -30 to 85°C, and so can be used in any possible outdoor temperature.

This module easily carries out WiMAX communication because a WiMAX driver is installed in the module, instead of the host device as is conventional.

The compact size of the PCI Express Half Mini Card was adopted, so that it can easily be installed in a device, and the module is equipped with the advanced functions demanded by the market especially for embedded systems, such as remote firmware upgrades and remote log acquisition.

Masahito Kamimura
Masamitsu Ogasawara
Takefumi Fuura
Masaru Yachi
Kazunori Nakada
Yugo Sugizaki

- Special Issues 2 : Communication Equipment -

JRC has developed a wireless LAN module compliant with IEEE802.11a/b/g/n. The applicable frequencies fully cover the wireless bands of Japan: 2.4GHz, 5.2GHz, 5.3GHz and 5.6GHz.

PCI-Express was adopted for the interface, and as an embedded module it has wide usability. The realization of the small size of the half mini card makes it easy to install in an embedded system.

The data transmission rate is raised by the incorporation of high speed technologies including MIMO (2x2) , and an effective throughput of about 200Mbps is realized, which allows high-speed communication of higher resolution images, large amounts of Internet data, etc.

Masaru Mitobe
Toshihiro Nemoto
Yoshito Nakabata
Yasunori Kuroda
Keisuke Yamanaka

- Special Issues 2 : Communication Equipment -

Digital modulation wireless devices are well suited for effective data transmission at specific radio frequencies, which are now limited resources, available bands of frequencies being narrower than conventional FM radio equipments. Combined with the improving transmission efficiency, the user-friendliness of these devices is thus greatly increasing. On the other hand, FM radio equipments are able to pick up communications to some extent if the noise of the environment is at the level of reception sensitivity or below, while digital radio equipments are either able to pick up the communication or not. Depending on conditions, trouble may occur in which communication is interrupted and cannot be understood . This tendency becomes pronounced in mountain areas and spaces between buildings in urban areas, and the use of digital radios in such 'dead zones' is a problem.

JRC integrated its strong expertise in GPS technology and radio equipment technology, and has commercialized an advance base station which is excellent in dealing with dead zones.

Shuichi Takahashi
Shuryu Takaoka
Shinobu Katayanagi
Jyunya Tanaka

- Special Issues 2 : Communication Equipment -

JRC has developed various types of public safety radio equipments, including modules that have a wide range of uses as the transmitter/receiver of public safety radio systems. The transmitter/receiver, ADDA converter, signal processor, and controller are included in one RFLSI which is mounted on a PC board together with the VCO and power unit to make a module. Digital signal processing achieves high neighboring channel selectivity. By putting the above functions in an LSI, the external shape and size could be made [width 25mm×depth 25mm×height 3mm], 1/10 the area of a PC board that has equivalent functions. A proprietary evaluation board for this module has been prepared, which can be used to make the development of transmitter/receivers quicker and more efficient.

Osamu Watanabe
Osamu Ajiki
Akira Haraguchi

- Technical Papers -

Development of essential system for a low-carbon society, which is a countermeasure against global warming, has been required. The JRC conducted field trials for more efficient low-carbon society by using ICT in Hita City, Oita Prefecture, which uses solar power and wind power and biomass power. Using a wireless telecommunications system of the VHF band (digital dividend) of analog television, for the analysis of natural energy power generation and power consumption analysis, demonstrated that it can reduce emissions of CO2. This wireless telecommunications system contribute to standardization as a method using a broadband VHF band based on these results, further, are recognized in the international standardization organizations, and contributed to spreading globally.

Hitoshi Itoh
Masahiro Oka
Masami Ooi
Toshihiko Miyake
Kazutoshi Tsuda

- Technical Papers -

In preparation for achieving the millimeter-wave broadband wireless system aimed at seamless connection with the optical fiber communication network, JRC has developed key devices such as baseband signal processing SoC with the high-speed multi-level QAM modem, SiGe I/Q quadrature modulator and demodulator MMIC, and GaAs frequency converter MMIC. JRC has also prototyped the small and broadband 38 GHz band point-to-point wireless system using TDD mode with dynamic radio resource control that adopts the configurations of dual antennas with high spatial isolation capitalizing on the characteristic of smaller antenna area in the millimeter-wave band. The performance that the maximum effective throughput of 64QAM is 1 Gbps at the radio clock frequency of 200 MHz, has been achieved.

Toru Taniguchi
Masatoshi Nagayasu
Toshifumi Shirosaki
Hideaki Yoshida
Yasuhiro Toriyama
Kazuya Kojima