M-Ary Aggregate Spread Pulse Modulation for Robust and Scalable Low-Power Wireless Networks

In this paper we present an overview of the M-ary Aggregate Spread Pulse Modulation (M-ASPM), and provide an assessment of its suitability and advantages for use in low-power wide-area networks (LPWANs). Notably, M-ASPM combines high energy-per-bit efficiency, robustness, resistance to interference, and a number of other favorable technical characteristics, with the spread-spectrum ability to maintain the network capacity while extending its range. We quantify the impact of mutual interference of multiple M-ASPM transmitters and demonstrate how such capacity-preserving range extension can be achieved for numerous desired areal distributions of the uplink nodes. Throughout the paper, LoRa is used for benchmark comparison and quantification of various M-ASPM features. In particular, we show that, while sharing many essential properties with LoRa, M-ASPM provides far more effective network range extension. When used in the same manner as LoRa, M-ASPM can serve as an appealing LoRa alternative. In addition, while being different LPWAN solutions, M-ASPM and LoRa can be designed to concurrently operate in the same spectral band and geographical area, cooperatively complementing each other’s coverage.