1) Smart antenna, software radio, together with advanced base station are the key techniques to achieve adaptability of wireless access points to diverse terminals, i.e. to make radio systems and air networks re-configurable
2) Hierarchical and ubiquitous as well as overlay cellular systems, including picocell, microcell, macrocell, and magecell ones, implement seamless network interconnection of both symmetric and asymmetric nature, and seamless terminal handoff of both horizontal and vertical levels respectively.