Design and evaluation of an LQI-based beaconless routing protocol for a heterogeneous MSN.

In a mobile sensor network with a mobile sink, choosing the next hop depends on the current location of the sink. This necessitates a frequent update of routing paths within the network. In this paper, a link quality indicator (LQI) measured by a sensor when receiving a POLLING packet directly from the sink is employed to acquire the relative position of the sensor to the sink. By doing so, the sensor chooses the next hop with a higher LQI value (alternatively, closer to the mobile sink). Due to the heterogeneity of transmission power and for guaranteeing the reachability of the chosen next hop, an energy-efficient and reliable LQI-based beaconless routing (LQI-BLR) protocol is proposed in this paper. To avoid flooding REPOLLING packets, only the sensors with low LQI values are allowed to broadcast the REPOLLING packet to create a routing path for the sensors outside the transmission range of the sink. Through analytical and simulation approaches, the performance of LQI-BLR and the leader-based routing (LBR) Burgos et al. (Sensors 17(7):1587, 2017. 10.3390/s17071587) is compared. With extensive real-scenario simulations, we successfully show that LQI-BLR outperforms LBR Burgos et al. (Sensors 17(7):1587, 2017. 10.3390/s17071587) and the data-driven routing protocol (DDRP) Shi et al. (Int J Commun Syst 26(10):1341–1355, 2013. 10.3390/s17071587 in terms of packet delivery ratio, energy consumption, and packet delivery delay. [ABSTRACT FROM AUTHOR]