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.

无线传感器网络（WSN）的分布式节点之间相互协作以模拟虚拟多天线系统，从而获得与常规MIMO系统相似的收益。在WSN中，这种系统称为协作多输入多输出（CMIMO）系统。CMIMO系统具有巨大的能力来改善WSN的性能。但是，对数据速率的不断增长的需求以及所需的服务质量（QoS）使得必须恢复1990年代初最初对CMIMO的认识。因此，本文确定了几种新兴的支持技术，例如压缩感知（CS），同时无线信息和功率传输（SWIPT），空中计算等，这些技术可以集成到CMIMO框架中，以增强网络性能。吞吐量，延迟，能源效率（EE）等。由于包含了这些新颖的思想，因此有必要进一步探索WSN中的CMIMO及其相关的挑战和可能的解决方案。本文提供了CMIMO WSN的全面概述及其挑战，这些挑战已基于协议栈的各个层进行了分类。由于能源效率是能源稀缺的WSN中的关键问题，因此已经详细讨论了节能技术。此外，挑战和悬而未决的问题也被强调出来，这为该领域的研究提供了新的方向。本文提供了CMIMO WSN的全面概述及其挑战，这些挑战已基于协议栈的各个层进行了分类。由于能源效率是能源稀缺的WSN中的关键问题，因此已经详细讨论了节能技术。此外，挑战和悬而未决的问题也被强调出来，这为该领域的研究提供了新的方向。本文提供了CMIMO WSN的全面概述及其挑战，这些挑战已基于协议栈的各个层进行了分类。由于能源效率是能源稀缺的WSN中的关键问题，因此已经详细讨论了节能技术。此外，挑战和悬而未决的问题也被强调出来，这为该领域的研究提供了新的方向。