In the iort, when satcom is the preferred or the only available connection for iot-devices, mmtc is enabled by upcoming and established systems using sophisticated ma techniques. To close the radio-link between compact and battery powered devices, very low symbol rates must be chosen in many cases, due to the constraints of the link-budget. If at the same time ma interference must be tolerated, orthogonal signaling with sic receivers is usually the physical layer technology of choice in many iot solutions. While sic has been investigated for medium and high data rates, pn poses additional challenges for very low data rate transmission. We derive a general performance estimation applicable to sic-based transmission schemes under pn with different levels of orthogonality between the user signals. Realistic values for the PN are derived from a PN-model that includes all relevant PN-processes and is parametrized by measurements of the Allan variance of real hardware. It is shown that PN strongly limits the performance of systems with high orthogonality at symbol rates below 1kHz, while systems with less orthogonal transmit signals and lower spreading gain are more robust.    «

In the iort, when satcom is the preferred or the only available connection for iot-devices, mmtc is enabled by upcoming and established systems using sophisticated ma techniques. To close the radio-link between compact and battery powered devices, very low symbol rates must be chosen in many cases, due to the constraints of the link-budget. If at the same time ma interference must be tolerated, orthogonal signaling with sic receivers is usually the physical layer technology of choice in many iot...    »