  Dynamic spectrum sharing paradigm is envisaged to meet the growing demand for
the Radio Frequency (RF) spectrum. There exist several technical, regulatory,
and business impediments for adopting the new paradigm. In this regard, we
underscore the need of characterizing and quantifying the use of spectrum by
each of the individual transmitters and receivers.
  We propose MUSE, a methodology to characterize and quantify the use of
spectrum in the space, time, and frequency dimensions. MUSE characterizes the
use of spectrum by a transmitter at a point in terms of the RF power occupied
by the transmitter. It characterizes the use of spectrum by a receiver at a
point in terms of the constraints on the RF-power that can be occupied by any
of the transmitters in the system in order to ensure successful reception. It
divides the spectrum-space into discrete unit-spectrum-spaces and quantifies
the spectrum used by the individual transceivers in the discretized spectrum
space.
  We characterize the performance of the spectrum management functions in the
discretized spectrum-space and illustrate maximizing the use of spectrum. In
order to address the challenges for the dynamic spectrum sharing paradigm, we
emphasize on articulating, defining, and enforcing the spectrum-access rights
in the discretized spectrum-space.
