Dealing with the Hidden Node Problem in Multioperator LAA-LTE Scenarios
Pablo Campos, Ángela Hernández‐Solana, Antonio Valdovinos-Bardají · 2018
LTE operation in unlicensed spectrum bands, based on Licensed-Assisted Access (LAA-LTE), is nowadays considered as an option to increase the capacity of 4G wireless networks. These solutions use a Listen Before Talk (LBT) protocol that enables the eNodeB (eNB) to opportunistically access the medium avoiding collisions from/to other eNBs or Wi-Fi stations. However, the hidden node problem in the context of LAA-LTE networks is a challenge that must be addressed in order to reduce or avoid the degradation of the network. Identifying hidden nodes and understanding the main metrics concerning their behavior will make it possible to take intelligent decisions and to improve the efficiency of LAA. In this work, different LAA-LTE scenarios with hidden nodes are analyzed. The results show that it is possible to detect the presence of hidden nodes by only using CQI (Channel Quality Indicator) metrics, and also that there is a set of metrics associated to hidden nodes that make it feasible to understand why and how much a hidden node degrades the network performance.