Where Is the Complexity?

Where Is the Complexity?
As we indicated earlier, the complexity of radio propagation and its variability from one
deployment situation to another pose major challenges in the design of efficient wireless
information networks. The fundamental design objective will be to provide good signal
coverage and reliable, high-quality service on each link. Thus, the designer must focus
on air-interface performance, which in turn places emphasis on PHY- and MAC-layer
designs. Because of this, research must continue to address a variety of complex signalprocessing
techniques, including new time, space and frequency diversity techniques,
with the objective of achieving steadily higher data rates, better service quality, and
increased spectrum utilization.
Related technologies are being pursued as well, including wireless positioning and
optical communications.Wireless positioning is a particular example of new technology
that is affected critically by the complexity of the radio propagation environment, and
we can expect that increasingly sophisticated propagation modeling techniques will be
required as this area of application becomes more important.