Updating Not Just Payload but Payload and Extra Data Simultaneously in Real-Time IoT Networks

A real-time Internet of Things (IoT) status update system is considered, where the IoT device needs to send not only the interested sensing information (payload) but also the controlling information (extra) to the destination for improving the quality of service. To simultaneously transmit these two types of information, a promising coding scheme, i.e., free-ride code, is utilized, in which the 5G low-density parity-check coded sensing sequence is superposed on randomly coded controlling sequence and is delivered to the destination without consuming additional bandwidth and power resources. The average age of information (AAoI) is evaluated for both two types of information. Numerical simulations indicate that the AAoI of extra can be reduced by free-ride codes without impairing the one of payload.