Internet of Things in the 5G Mobile Communication System: The Optimal Number of Channels in Channel Hopping

One of the typical goals of the 5G mobile communication system1 is to establish an Internet of Things (IoT)2 environment in which all objects are connected to the network to generate and share information through not only mobile terminals but also mobile communication infrastructure. 5G must support Machine-Type Communication (MTC)3 in IoT, and it must effectively support many devices distributed at high density. The IoT environment for MTC support has low transmission power and a narrowband channel environment and interference environment so that many devices can connect with minimum energy. In this environment, data transmission performance is negatively affected by retransmission, deep fading, and interference. One way of solving this problem is to propose various kinds of channel-hopping methods in which a frequency is periodically changed every time a packet is transmitted. However, current channel-hopping techniques do not indicate the proper number of channels to be used. In this paper, we propose the Optimal Number of Channels (ONC) in channel hopping algorithm, a reference method that can provide the optimal channel number to improve channel performance in 5G massive IoT environments. We show that using a hopping method that minimizes service inefficiency reduces the number of channels and improves the Quality of Service (QoS) of the channel.