Adaptive C-OFDM system at 30 GHz for the last mile wireless broadband access to interactive services

In this paper a wireless local multipoint distribution system (LMDS) at 30 GHz for the last mile broadband distribution to users of interactive services is investigated. The system we propose users a coded OFDM transmission scheme with FDM and/or TDM multiplexing techniques and adaptive carrier allocation to counteract the effects of the wireless communication channel. An urban microcell in an actual propagation environment is analyzed by means of a ray-tracing tool. Coverage probability is defined and investigated and the choices of the optimum multiplexing technique and carrier allocation algorithm are discussed. It is found that a pure FDM technique with adaptive carrier allocation and priority to users having the largest path loss leads to the best performance.