Title: A low-complexity demodulation for oversampled LoRa signal
Authors: Vincent Savaux
Addresses: Advanced Connectivity Lab., b<>com, 35000 Rennes, France
Abstract: This paper deals with a demodulation technique for oversampled LoRa signal. The usual maximum likelihood (ML) based demodulation method for LoRa chirp spread spectrum (CSS) waveform is dedicated to signals sampled at Nyquist rate, whereas considering oversampled signals may improve the performance of the LoRa demodulation process. Accordingly, when an oversampling rate (OSR) 2 is assumed, the suggested method consists of applying two demodulation processes to the even and odd samples of the oversampled LoRa signal, and then combining the results. This principle is then generalised to any OSR, and we show that the complexity of the method is low since it only involves discrete Fourier transforms (DFT). Moreover, a performance analysis in terms of symbol and bit error rate (SER and BER) is presented considering both additive white Gaussian noise (AWGN) and Rayleigh channel models.
Keywords: LoRa; demodulation; equalisation; maximum likelihood; low-complexity.
DOI: 10.1504/IJMNDI.2022.126452
International Journal of Mobile Network Design and Innovation, 2022 Vol.10 No.3, pp.148 - 153
Received: 18 Dec 2021
Accepted: 30 Dec 2021
Published online: 26 Oct 2022 *