Development of high speed Ethernet-based wireless access system (EWA) for the 5 GHz band

This paper presents the high-speed Ethernet-based wireless access system (EWA) as a prototype of the IEEE 802.11 TGa standard. EWA consists of stations (STAs) connected to user´s PC and access points (APs) connected to Ethernet. The orthogonal frequency division multiplexing (OFDM) scheme is one of the most promising techniques for high data rate wireless access systems in severe propagation environments since it is very robust against multipath fading channels. In July 1998, IEEE 802.11 task group a (TGa) selected the OFDM technique, which was jointly proposed by Lucent Technologies and NTT, as the physical layer standard in the 5 GHz band. EWA is the first system that uses OFDM following TGa. Moving picture transmission is realized by EWA over an air interface between AP and STA with 20 Mbit/s radio access