Abstract
Internet of Things is arising as the technology of the future where an estimate of many of devices around us will be connected to the internet. When all of these nodes and sensors get connected to the cloud, a huge portion of their energy is consumed by their wireless communication systems. However, most of them have a highly constrained power budget. With billions of data being transmitted through the IoT nodes, the specifications instruct an ultra-low power design with secure communication. Thus, this paper provides an overview of the design considerations and challenges of wake-up receivers as well as an analysis of state-of-the-art research. A comparison of some existing architectures is also detailed. Perspectives and future work to optimize wake-up receiver limitations are presented.