Site:                NEC C&C Media Research Laboratories
                      Miyazaki 4-1-1, Miyamae-ku
                      Kawasaki, 216-8555
                      Japan

Date Visited:  1 June 1999

WTEC Attendees: R. Pickholtz (report author), R. Rao, B. Mooney, W. Stark, N. Moayeri

Hosts:            Akihisa Ushirokawa
                      Minoru Shikada
                      Kojiro Hamabe
                      Kenji Takeda
                      Kazuhiro Okanoe
                      Hiroshi Furukawa
                      Kenichi Ishii

BACKGROUND

The Computer and Communications (C&C) Research Laboratories is an outgrowth of the original NEC Research Laboratories, first established in 1939. The current structure was established in 1993 in response to the convergence of the two disciplines. NEC ranks sixth and seventh in sales of C&C products. In 1993 sales were $36.85 billion, 35% of which was communications, 40% computer and 20% electronic devices. The C&C Laboratories primary focus is in three main areas: computers, devices and networks wireless systems span all three of these areas: At the center, the panel visited at Kawasaki, Kanagawa, there were about 1,600 employees and a Research Institute 1,400 of whom were graduate engineers.

There are 13 laboratories and centers at the Central Research Laboratories in Kawasaki, Kanagawa, housed in a modern complex. The C&C Media Research Laboratories, which the panel visited, is the largest with 300 people. Its three-fold mission is networking, computer systems, and terminals together with any supporting system software. It is under the network mission that wireless lies along with Future Network Architectures, ATM, Internet, Optical Networks, and Access Technologies (cables, fiber, wireless).

NEC also operates smaller R&D centers in Europe and the United States and a Research Institute in Princeton.

SYNOPSIS

After introductions, an overview of the NEC R&D Group was presented with questions and answers. A brief talk "Mobile Multiuser Wireless Networking with High Mobility and a Flexible System Deployment"was presented describing the R&D mission. This vision, which would allow transmission speeds close to 150 mbps and 10-20 km cell coverage was identified as "4th Generation." Specific research topics included High-Speed Wireless LAN, Software Radio/RF circuits, concept, and network architectures.

Several laboratory tours followed, including interactive discussions with researchers about their projects.

Among the devices the panel viewed were a 2.5 GHz (Japan's ISM Band) testbed for a 25 Mbps W-LAN using CSMA medium access protocol built on a card; a hardware testbed WCDMA including multistage parallel, successive interference cancellation simulating 3 users in a multi-path Rayleigh fading channel operating at currently envisioned 4.096 Mbps in a 5 MHz band; and two diversity branches plus four finger RAKE receiver using soft VA decoding concatenated with (hard input) RS (36, 32;256). For multimedia use, it is envisioned that the higher power, high rate data users (256 kbps) would be cancelled from the received composite. Performance curves were impressively close to theoretical limits.

Further discussions revealed that individual researchers believe that spatial processing/beam forming at the base station will be very important for future wireless systems to reduce interference, power required, multi-path. A major issue is propagation effects: shadowing and blocking in metro access. Mobile computing will require a new mobile IP and, for various reasons relating to channel conditions, routing and handoff, re-examining all the layers of the protocol stack will be needed. There is also a need to define user QOS and the functional relationship between this ultimate QOS and the individual QOS parameters at each layer.

PROPOSED RESEARCH AREAS

POTENTIAL COLLABORATIONS

Kazuhiro Okanoe, Hiroshi Furukawa, Akihisa Ushirokawa


Published: July 2000; WTEC Hyper-Librarian