A comprehensive review of cooperative MIMO WSN: its challenges and the emerging technologies

Abstract

The distributed nodes of a Wireless Sensor Network (WSN) cooperate among themselves to emulate a virtual multi-antenna system to get similar benefits as the conventional MIMO systems. In WSN, such a system is known as the Cooperative Multiple Input Multiple Output (CMIMO) system. A CMIMO system has an enormous capacity to improve the performance of a WSN. But the increasing demand in the data rate and the desired Quality of Services (QoS), necessitates a revival in the way CMIMO was originally perceived in the early 1990s. Therefore, this article identifies several emerging supportive technologies such as the Compressive Sensing (CS), Simultaneous Wireless Information and Power Transfer (SWIPT), over the air computation, etc. which can be integrated to the CMIMO framework for enhancing the network performance in terms of throughput, delay, Energy Efficiency (EE), etc. The inclusion of these novel ideas necessitates further exploration of CMIMO in WSN along with its associated challenges and their possible solutions. This article provides a comprehensive overview of a CMIMO WSN along with its challenges which have been classified based on the layers of the protocol stack. Since energy efficiency is a key concern in a WSN having scarce energy resources, the energy-saving techniques have been discussed in detail. Further, challenges and open issues have also been highlighted which opens up new research direction in the area.