Energy Efficient LPWAN Decoding via Joint Sparse Approximation

Abstract

We propose a sparse approximation based joint-decoding system for LPWAN (LoRa) PHY-layer frame decoding. Recent research has shown that joint-decoding raw radio ADC samples in the Cloud offloaded from LPWAN gateways can decode weak radio signals by combining coherent frames. However, this approach requires high network bandwidth usage to collect a large amount of ADC samples from each gateway, which results in network congestion and high financial cost due to Internet data usage between the gateway and the Cloud server. In order to reduce the bandwidth usage of this data offloading operation, we propose a LPWAN packet acquisition mechanism based on joint sparse approximation.