**7. Conclusions**

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. 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. The electromagnetic energy is converted to DC energy that may be employed to charge batteries, wearable medical devices, IOT, laptop batteries and commercial Body Area Networks, BANs. The harvesting energy system operates as a dual mode RF harvesting system. The harvesting unit can be part of a medical, IOT, computer, and smartphone. The notch and slot antennas were analyzed by using 3D full-wave software. Harvested power from RF transmitting links is usually lower than 0.1 μW/ cm2 . All antennas presented in this chapter can operate also as active antennas. Active antennas may improve the energy harvesting system efficiency. The wideband RF energy harvesting system consists of wideband antenna, DC and control unit, a rectifying circuit, and a rechargeable battery. The harvesting energy system operates as a Dual Mode Energy harvesting system. The active devices DC bias voltages are supplied by the communication system. The wideband programmable energy harvesting panel can harvest energy in frequencies from 150 MHz to 18GHz as part of communication, medical, and IOT systems. The antennas presented in this chapter provide a wideband wearable communication system with a wideband RF harvesting system. There is a good agreement between computed and measured results.
