  Radio pollution and power consumption problems lead to innovative development
of green heterogeneous networks (HetNet). Time reversal (TR) technique which
has been validated from wide- to narrow-band transmissions is evaluated as one
of most prominent linear precoders with superior capability of harvesting
signal energy. In this paper, we consider a new HetNet model, in which
TR-employed femtocell is proposed to attain saving power benefits whereas
macrocell utilizes the beam-forming algorithm based on zero-forcing principle,
over frequency selective channels. In the considered HetNet, the practical case
of limited signaling information exchanged via backhaul connections is also
taken under advisement. We hence organize a distributed power loading strategy,
in which macrocell users are treated with a superior priority compared to
femtocell users. By Monte-Carlo simulation, the obtained results show that TR
is preferred to zero-forcing in the perspective of beamforming technique for
femtocell environments due to very high achievable gain in saving energy, and
the validity of power loading strategy is verified over multipath channels.
