|Budget Amount *help
¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥1,600,000 (Direct Cost : ¥1,600,000)
This project dealt with Ad-hoc Wireless networks with IP packets and/or ATM cells for future advanced communications networks. The objectives of the project is to present high-reliable and high-flexible wireless network architecture for factory LANs, Campus LANs and emergency communications networks. This project mainly focuses on layered self-organized networking, data error control, media access control for both TDMA and CDMA communications environment. As results for two year research project, we obtained as follows.
1) This project proposed an dynamic data error control methods which integrates ARQ, FEC, and Bit-Interleaving, depending on the condition of wireless transmission links in the networks.
2) In the self-organizing process of linkage between a base station (BS) and mobile stations (MSs), effective channel assignment protocol is one of essential elements in order to construct highly performed networks. This project presented three algorithms, evaluated them by computer simul
ations, and proposed a channel assignment protocol considering the interference between neighboring links as suitable one.
3) This paper presented two media access control methods suitable for multimedia communications ; DQRUMA/PAR innovated from DQRUMA in TDMA environment and PRMA/URU innovated from PRMA in CDMA environment. The project evaluated them and compared with original protocols and other popular one and shown their effectiveness numerically.
4) On the process of the research according to the planning schedule, the project found out a new and very effective access control protocol named in CDMA environment named as CDMA/CSMA/CF (Code Sense Multiple Access with Collision Free Mode). When we use CSMA protocol for CDMA, this protocol assure no packed collisions and improve system performance significantly. In this project, there is not sufficient time to check and show the whole performance of new protocol, but we make sure that the protocol has great potential for future wireless CDMA communications by the basic performance evaluations. Less