Low-Latency Frame Forwarding Scheme Applicable to the Heterogeneous Channel Allocated Low-Energy Wireless Grid Structure

The paper proposes an effective low-latency frame forwarding scheme for the wireless grid structure that assumes heterogeneous channel allocation. In the assumed structure of the wireless grid, several numbers of radio devices autonomously and automatically harmonize together and exchange data frames to effectively realize the required Internet of Things (IoT) specified functions in Beyond 5^th Generation (B5G)/6^th Generation (6G) systems. The assumed structure employs IEEE 802.15.4g/4e compliant Medium Access Control (MAC) that enables expansions of the service available areas by conducting the multi-hop transmission, and low-energy operation by suitably exploiting the sleeping periods. By considering several complicated and advanced applications, the superframe structure that is defined by IEEE 802.15.4e can be customized to provide the low-latency frame exchange. On the other hand, the structure also enables different frequency channel allocation in the same device network that enables capacity increase as well as interference avoidance. The proposed scheme is an enhancement of such wireless grid structure and is to enable the low-latency frame exchange even under the heterogeneous channel allocated situations. The proposed scheme also works very effective to satisfy such complicated and diversified requirements in the IoT testbed environment where the testbed users evaluate such systems and services in B5G/6G era. In the paper, improved performances on the frame forwarding by the proposed scheme is investigated via the computer simulations. Furthermore, the improved performances of the proposed scheme are also evaluated via the experiments employing the operational Smart Utility Network (SUN) devices. The paper has confirmed the proposed scheme drastically improve the data forwarding latency performance under the heterogeneous channel allocated situations.