A system and method of inventorying multiple objects utilizing a
multi-level or a chained radio frequency identification system. The
system includes a master tag and a plurality of upper level tags and
lower level tags associated with respective objects. The upper and lower
level tags communicate with each other and the master tag so that reading
of the master tag reveals the presence and absence of upper and lower
level tags. In the chained RF system, the upper and lower level tags
communicate locally with each other in a manner so that more remote tags
that are out of range of some of the upper and lower level tags have
their information relayed through adjacent tags to the master tag and
thence to a controller.