  Beaconless position-based forwarding protocols have recently evolved as a
promising solution for packet forwarding in wireless sensor networks. However,
as the node density grows, the overhead incurred in the process of relay
selection grows significantly. As such, end-to-end performance in terms of
energy and latency is adversely impacted. With the motivation of developing a
packet forwarding mechanism that is tolerant to node density, an alternative
position-based protocol is proposed in this paper. In contrast to existing
beaconless protocols, the proposed protocol is designed such that it eliminates
the need for potential relays to undergo a relay selection process. Rather, any
eligible relay may decide to forward the packet ahead, thus significantly
reducing the underlying overhead. The operation of the proposed protocol is
empowered by exploiting favorable features of orthogonal frequency division
multiplexing (OFDM) at the physical layer. The end-to-end performance of the
proposed protocol is evaluated against existing beaconless position-based
protocols analytically and as well by means of simulations. The proposed
protocol is demonstrated in this paper to be more efficient. In particular, it
is shown that for the same amount of energy the proposed protocol transports
one bit from source to destination much quicker.
