Impact of Outdated Channel State Information and Line-of-Sight Power on Age of Information

Using a practical relay model, in which an energy transmitter (ET) transmits energy to a sensory node S and an information receiver D, information freshness or age of information (AoI) under outdated-channel-state-information (oCSI) severity and line-of-sight (LoS) power is examined in this paper. The sensory node—equipped with a finite-size-battery capacitor—harvests energy from the ET to sustain its operation. Rician fading under non-oCSI and oCSI environments is employed to study the AoI, in which benefits and severity of LoS power and oCSI will be elaborated. The proposed AoI results exactly reduce to existing ones under Rayleigh fading, which validates this work. Simulation results are additionally deployed to validate the proposed AoI results. Impact of parameters such as capacitor capacity, system incoherence coefficient and spectral efficiency on AoI under specific scenarios is also discussed.