  We suggest a novel multifrequency broadband plasmonic Yagi-Uda-type
nanoantenna equipped with an array of tapered directors. Each director can be
used for the excitation of the antenna by nanoemitters matched spectrally with
the director resonant frequency and placed in the director near-field region.
Multifrequency op- eration of nanoantennas provides tremendous opportunities
for broadband emission enhancement, spectroscopy and sensing. By the principle
of reciprocity, the same tapered nanoantenna architecture can be used both as a
transmitter and/or as a receiver, thus being useful for creating a broadband
wireless communication system.
