English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

This paper considers a cooperative Internet of Things (IoT) system with asource aiming to transmit randomly generated status updates to a designateddestination as timely as possible under the help of a relay. We adopt arecently proposed concept, the age of information (AoI), to characterize thetimeliness of the status updates. In the considered system, delivering thestatus updates via the one-hop direct link will have a shorter transmissiontime at the cost of incurring a higher error probability, while the delivery ofstatus updates through the two-hop relay link could be more reliable at thecost of suffering longer transmission time. Thus, it is important to design therelaying protocol of the considered system for optimizing the informationfreshness. Considering the limited capabilities of IoT devices, we propose twolow-complexity age-oriented relaying (AoR) protocols, i.e., thesource-prioritized AoR (SP-AoR) protocol and the relay-prioritized AoR (RP-AoR)protocol, to reduce the AoI of the considered system. By carefully analyzingthe evolution of the instantaneous AoI, we derive closed-form expressions ofthe average AoI for both proposed AoR protocols. We further optimize thegeneration probability of the status updates at the source in both protocols.Simulation results validate our theoretical analysis, and demonstrate that thetwo proposed protocols outperform each other under various system parameters.Moreover, the protocol with better performance can achieve near-optimalperformance compared with the optimal scheduling policy attained by applyingthe Markov decision process (MDP) tool.

Optimizing Information Freshness for Cooperative IoT Systems with Stochastic Arrivals