Wideband Systems with Energy Harvesting Units for 5G, Medical and Computer Industry

*Albert Sabban*

### **Abstract**

Demand for green energy is in tremendous growth in the last decade. The continuous growth in production of portable RF systems increase the consumption of batteries and electrical energy. Batteries and conventional electrical energy increase the environmental pollution. Compact wideband efficient antennas are crucial for energy harvesting commercial portable sensors and systems. Small antennas have low efficiency. The efficiency of 5G, IoT communication and energy harvesting systems may be improved by using wideband efficient antennas. Ultrawideband portable harvesting systems are presented in this chapter. This chapter presents new Ultra-Wideband energy harvesting system and antennas in frequencies ranging from 0.15GHz to 18GHz. Three wideband antennas cover the frequency range from 0.15GHz to 18GHz. A wideband metamaterial antenna with metallic strips covers the frequency range from 0.15GHz to 0.42GHz. The antenna bandwidth is around 75% for VSWR better than 2.3:1. A wideband slot antenna covers the frequency range from 0.4GHz to 6.4GHz. A wideband fractal notch antenna covers the frequency range from 6GHz to 18GHz. Printed passive and active notch and slot antennas are compact, low cost and have low volume. The active antennas may be employed in energy harvesting portable systems. The antennas and the harvesting system components may be assembled on the same, printed board. The antennas bandwidth is from 75–200% for VSWR better than 3:1. The antennas gain is around 3 dBi with efficiency higher than 90%. The antennas electrical parameters were computed by using 3D electromagnetic software in free space and in vicinity of the human body. There is a good agreement between computed and measured results.

**Keywords:** green energy, energy harvesting, wideband antennas, metamaterial antenna, notch, slot antennas

#### **1. Introduction**

This chapter presents new Ultra-Wideband programmable communication systems with energy harvesting modules and efficient compact antennas in frequencies ranging from 0.15GHz to 18GHz. In last twenty years free space energy in the forms of light, heat, vibration, electromagnetic waves, muscle motion and other type of energy, is used to produce green energy. Methods to produce green electricity from these different types of energy sources have been presented and investigated [1–4]. Energy harvesting systems provide green energy and may eliminate the need to replace batteries every day and the usage of power cords. Batteries and cables waste pollute the environment. To use as much free space energy as possible it is important to harvest the electromagnetic power from wideband range of wireless communication systems. In these cases, we should use ultra-wideband antennas. Moreover, a programmable array with two to four antennas can harvest energy from 100 MHz to 18GHz. The energy harvesting antenna must satisfy the requirements related to the system application. Due to considerably low-power electromagnetic energy densities in free space, highly efficient antennas are significant. Patch, slot, and dipole antennas were employed to harvest electromagnetic energy [4–7]. Printed antennas are used in communication and medical system [4–25]. Wideband slot and notch antennas may be used in wideband harvesting energy systems. Slot and notch antennas have low volume, low weight, low cost, and are flexible. Moreover, a compact low-cost energy harvesting network and matching network may be produced by integrating the system RF components with the resonators on the same board. Printed compact antennas are widely presented in the literature in the last twenty years as referred in [7–25]. Human body effect on the electrical performance of wearable medical system and antennas at microwave frequencies should be considered. Electrical properties of human tissues have been presented in several papers such as [26–27]. Several wearable antennas were presented in books and papers in the last years as referred in [27–36]. Printed notch and slot antennas for harvesting energy applications are rarely presented in the literature. New ultra-wideband wearable antennas for 5G, IOT and medical RF systems with energy harvesting units are presented in this chapter.
