Continuous radio-wave monitoring of the Geminid activity in December 1
992 and 1993 by using a forward scatter (FS) bistatic radar over the B
ologna-Lecce baseline (700 km) in Italy, reveals peculiar structural a
spects of the stream in terms of signal amplitude-rate and duration-ra
te dependence. The observational results of the Geminid display obtain
ed in the two consecutive years with differentiated peak levels of tra
nsmitted power, exhibit different time distributions of underdense met
eors against the signal received power. Both sets of the data relative
to the peak activity in December 12-14, show reflection properties of
Geminids which are atypical if compared with echoes from cometary-typ
e showers, with really high echo counts at mid-upper levels of the pea
k received power. An assymmetric curve of activity of the Geminids com
plex is evidenced, with the peak flux of smaller particles occurring e
arlier than that of larger ones.