1. UNB PHY layer

In order to offer a transmission system suited to the IoT and all its applications (figure 1 ), SigFox has developed an LPWAN network based on UNB, also known as the 0G network. Unlike 4G and 5G, which aim to increase transmission rates (at the cost of a spatially denser and algorithmically more complex architecture), the aim of 0G is to simplify the system, making it as efficient as possible for the transmission of small quantities of information. This simplification is achieved at the PHY (PHYsique) layer, detailed in this section, but also at the MAC (Media Access Control) layer, which will be presented in section ...