Performance Analysis of Carrier-less Modulation Schemes for Wireless Nanosensor Networks

Wireless Nano-scale Sensor Networks (WNSNs) are very simple and energy restricted networks that operate over terahertz band ranging from 0.1-10 THz, which faces significant molecular absorption noise and attenuation. Given these challenges, reliability, energy efficiency, and simplicity constitute the main criteria in designing communication protocols for WNSNs. Due to its simplicity and energy efficiency, carrier-less pulse based modulation is considered the best candidate for WNSNs. In this paper, we compare the performance of four different carrier-less modulations, PAM, OOK, PPM, and BPSK, in the context of WNSNs operating within the terahertz band. Our study shows that although BPSK is relatively more complex in terms of decoding logic at the receiver, it provides the highest reliability and energy efficiency among all the contenders. PAM has the worst performance in terms of reliability as well as energy efficiency. OOK and PPM have simpler decoding logic, but perform worse than BPSK in both reliability and energy efficiency.