BDMA testbed-configuration and performance results

A BDMA (band division multiple access) system is designed for the mobile telecommunications of the next generation. OFDM and SFH-TDMA techniques are applied to this system. OFDM is well known as the most promising modulation technique for high bit rate transmission mainly in the area of broadcast. We utilize these characteristics of OFDM for multiple access with variable bandwidth assignment capability, which we call the band division concept. Moreover, in the multi-cell operation such as cellular communication, an interference diversity effect by random frequency hopping between cells can also be expected. If interference averaging can be achieved, it is expected to have more capacity than the DS-CDMA system because of intra-cell orthogonality. The BDMA system is the first approach to apply a combination of OFDM and SFH-TDMA to a 2-way wireless multiple access system. Therefore, it is required to show the feasibility in many aspects by using an actual testbed. We are developing testbed for the BDMA system. This paper shows the testbed configuration and basic transmission performances which we have already implemented in our testbed. The results are very promising and show the feasibility of the BDMA system.