Internet of Things: A Review on Theory Based Impedance Matching Techniques for Energy Efficient RF Systems

Abstract

Within an increasingly connected world, the exponential growth in the deployment of Internet of Things (IoT) applications presents a significant challenge in power and data transfer optimisation. Currently, the maximization of Radio Frequency (RF) system power gain depends on the design of efficient, commercial chips, and on the integration of these chips by using complex RF simulations to verify bespoke configurations. However, even if a standard 50Ω transmitter’s chip has an efficiency of 90%, the overall power efficiency of the RF system can be reduced by 10% if coupled with a standard antenna of 72Ω. Hence, it is necessary for scalable IoT networks to have optimal RF system design for every transceiver: for example, impedance mismatching between a transmitter’s antenna and chip leads to a significant reduction of the corresponding RF system’s overall power efficiency. This work presents a versatile design framework, based on well-known theoretical methods (i.e., transducer gain, power wave approach, transmission line theory), for the optimal design in terms of power delivered to a load of a typical RF system, which consists of an antenna, a matching network, a load (e.g., integrated circuit) and transmission lines which connect all these parts. The aim of this design framework is not only to reduce the computational effort needed for the design and prototyping of power efficient RF systems, but also to increase the accuracy of the analysis, based on the explanatory analysis within our design framework. Simulated and measured results verify the accuracy of this proposed design framework over a 0–4 GHz spectrum. Finally, a case study based on the design of an RF system for Bluetooth applications demonstrates the benefits of this RF design framework.

Internet of Things: Development Intelligent Programmable IoT Controller for Emerging Industry Applications

“…For a small control system (eight input signals, four output signals), the previous PLC and HMI design can only display the information locally. To minimize the cost of the existing IoT devices is one of the main challenges [ 72 ]. If the user wants to view the system status in a different location, another computer must be added to view the system status from a different location, and the programming and related hardware are costly and require professional design help.…”

Progress of Materials and Devices for Neuromorphic Vision Sensors

“…To realize higher resolution and smaller chip size, compact design of individual components and overall circuits and further development of precision manufacturing techniques are required. In addition, when light spikes are repeatedly incident on the photosensor in the OSC, some amplitude of the voltage output signal supplied from the photovoltaic divider to the voltage output electrode may be lost due to the problem of impedance mismatch between elements [ 121 , 122 ]. This problem becomes more serious in the high-frequency optical spikes condition.…”

Reliability Analysis and Optimization of a Reconfigurable Matching Network for Communication and Sensing Antennas in Dynamic Environments through Gaussian Process Regression

“…By connecting the antenna to port 2, the network further reduces to a one-port network. As a way to quantify the performance of the system, the reflection coefficient S 11 and transducer gain G T are used [34,35]. These parameters can be calculated for a one-port network with…”