same band as a strong signal, as in a
TV broadcast, so regular users do not
see interference, but collaborating
radios distinguish between the different transmissions. Needed are richer
measurement studies that test more
locations and cover enough detail so
software and radio engineers are able
to estimate what sharing mechanisms
will work well and how much bandwidth a particular radio can access and
use; a first example of such a study appeared in 2010.7 More are needed.
Observe an important, though
often-ignored, point in the last paragraph. The nature of wireless research
is changing. The idea of simply testing
how a standardized wireless protocol
works under certain conditions (such
as urban vs. rural) is rarely useful research. In a world in which radios can
change their protocols in seconds, we
must discover which protocol should
run in those conditions and how a radio might learn about its environment
so it can instantiate the protocol.
But even before these more sophisticated measurements are done, it is
safe to say the current perceived shortage of wireless bandwidth is, in large
part, a function of our inability to exploit a hugely underused spectrum.
Wireless is a vital piece of our data-communications present and will be
an even more vital piece of the future,
with software in commercial radios
able to maximize that future.
Yet, looking over this article, I hope
it is clear that we (computer science, radio engineering, manufacturing, and
consumer and public-policy advocates)
suffer from myopia. For most key topics, including radio behavior, approved
use of the spectrum, and even how
poorly the spectrum is used today, we
have sometimes barely enough information to be excited about it and not
enough to make an informed decision
about how best to realize it. The point
worth repeating is we are ill-prepared
to make decisions about future use of
wireless data communications.
We must move briskly, however, or
risk missing the untapped promise of
the wireless spectrum. Research is the
way to fill the information gap, but in
a world where low-cost software radios
are beginning to appear, there’s little
time to do the research. Needed in-
stead is an evolving research plan.
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Craig Partridge ( firstname.lastname@example.org) is Chief scientist for
networking research at raytheon bbn technologies, an
aCM Fellow, and former chair of aCM sigCoMM.
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