Cross-layer network lifetime optimisation considering transmit and signal processing power in wireless sensor networks

Maintaining high energy efficiency is essential for increasing the lifetime ot wireless sensor networks (WSNs), where the battery of the sensor nodes cannot be routinely replaced. Nevertheless, the energy budget of the WSN strictly relies on the communication parameters, where the choice of both the transmit power as well as of the modulation and coding schemes (MCSs) plays a significant role in maximising the network lifetime (NL). In this paper, we optimise the NL of WNSs by analysing the impact of the physical layer parameters as well as of the signal processing power (SPP) P_sp on the NL. We characterise the underlying trade-offs between the NL and bit error ratio (BER) performance for a predetermined set of target signal-to-interference-plus-noise ratio (SINR) values and for different MCSs using periodic transmit-time slot (TS) scheduling in interference-limited WSNs. For a per-link target BER requirement (PLBR) of 10^-3, our results demonstrate that a `continuous-time´ NL in the range of 0.58 - 4.99 years is achieved depending on the MCSs, channel configurations, and SPI.