QoS-based adaptive modulation under rainfall environment in gigabit millimeter-wave broadband wireless access system

In the gigabit millimeter-wave broadband wireless access (Gb MMW BWA) system. Quality of MMW is strongly affected by rainfall hence the MMW link may fall down in the case of heavy rainfall. The making of route detour to avoid that heavy rain zone is expected to improve the quality. For that matter, however, it may be not sufficient to provide the high-traffic demands. Therefore, in this paper, we propose the QoS-based adaptive modulation scheme to compensate for rain attenuation, and thus to improve the spectrum efficiency of system.