**4.1 Wearable microstrip antennas for 5G and medical systems**

Microstrip antennas are etched on a low loss dielectric substrate. A crosssectional view of the microstrip antenna electric fields is presented in **Figure 13**. Microstrip antennas are thin conducting patches etched on a substrate with dielectric constant εr and thickness H. Usually, H is less than 0.1 λ. Microstrip antennas are presented in [1–7]. The wearable antenna may be attached to the human body or inserted inside a belt.
