Energy Detection Based Carrier Sense in LPWAN

Extensive research has been conducted on imperfect carrier sense based on energy detection; however, the effect of the finite packet length, finite carrier sense period, and arbitrary start time of the carrier sense for the arrived signal on the result of the energy detection based carrier sense has never been investigated. This paper presents a detailed discussion on the performances of an energy detection based carrier sense in low-power wide-area network (LPWAN) to detect a target signal with power below the noise power and employ it over a wide communication area. We theoretically derive the finite packet length, finite carrier sense period, and arbitrary start time of the carrier sense as the signal detection deterioration factors. The performance of LPWANs with the energy detection based carrier sense is numerically verified based on these theoretical analyses. The numerical examples demonstrate that the energy detection based carrier sense improves the performance of LPWANs, and an optimum carrier sense level is determined based on the width of the communication area and the packet length on air around the end devices.