Análise da ortogonalidade imperfeita com um modelo de sinal LoRa

Abstract

With the growing number of devices connected to IoT, several network standards appear to attend requirements such as: scalability, energy efficiency, reliability, among others. With this, networks classified as LPWANs appear, they are networks that connect devices over long distances and low power. In this class of network, the LoRaWAN standard stands out, which uses a modulation based on CSS, which besides spreading the signal in a frequency band, transmits data through chirps. The present work analyzes LoRa modulation through models present in the literature. Mathematical and numerical analyzes of the correlation between LoRa signals are carried out, a factor that directly implies the scalability of the network, in addition to an analysis of the rejection between symbols. Finally, an analysis and a simulation campaign are performed using a demodulator in the literature. Formulas were found that show the correlation between all symbols that can be transmitted on the network. A table was also presented with the rejection between symbols of equal and distinct scattering factors.