Design and Performance Analysis of a Novel Constellation-Aided LoRa Communication System

To solve the low-transmission-rate problem of conventional Long-Range (LoRa) system, in this letter, we propose a novel constellation-aided (CA) LoRa scheme. In the proposed CA-LoRa system, PSK modulation, which is implemented with two LoRa signals that have <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pi /2$ </tex-math></inline-formula> phase difference, is employed to carry the additional information bits. We derive the theoretical expressions for bit-error-rate (BER) of the CA-LoRa system over additive white Gaussian noise (AWGN) and Rayleigh fading channels. Moreover, we analyze the throughput and complexity of the proposed CA-LoRa system. The analysis and simulation results demonstrate that the proposed CA-LoRa system has better BER performance while improving the transmission rate compared to the state-of-the-art LoRa modulation schemes. Therefore, the CA-LoRa system is promising as an alternative for Internet of Things (IoT) applications.