Wideband Wearable Antennas for 5G, IoT, and Medical Applications

*Albert Sabban*

### **Abstract**

Wearable compact antennas are a major part of every wearable 5G communication system, IoT, and biomedical systems. Several types of printed antennas are employed as wearable antennas. Printed dipole, microstrip antennas, printed loops, slot antennas, and PIFA antennas are employed as wearable antennas. Compact efficient antennas significantly affect the electrical performance of wearable communication systems. In several communication and medical systems, the polarization of the received signal is not known. The polarization of the received signal may be vertical, horizontal, or circular polarized. In these systems, it is crucial to use dual-polarized receiving antennas. The antennas presented in this chapter may be linearly or dually polarized. Design trade-offs, simulation results, and measured results on human body of small wideband printed antennas with high efficiency are presented in this chapter. For example, the low-volume dually polarized antenna dimensions are 50 50 0.5 mm. The antenna beamwidth is around 100°. The antennas gain is around 0–4 dBi. Metamaterial technology is used to improve the electrical performance of wearable antennas. The proposed antennas may be used in wearable wireless communication and medical RF systems. The antennas' electrical performance on human body is presented in this chapter.

**Keywords:** wearable antennas, 5G communication system, IoT, biomedical systems, metamaterial technology, metamaterial antennas, microstrip antennas

#### **1. Introduction**

Microstrip antennas are widely used in communication system and seekers. Microstrip antennas possess attractive features that are crucial to 5G communication, IoT, and medical systems. These antennas are compact, flexible, lightweight, and relatively cheap. In addition, we can integrate the RF modules with the antennas on the same substrate. Printed antennas have been widely presented in the literature in the last 20 years [1–9]. Electromagnetic fields' transmission losses of human tissues have been investigated in the papers [10, 11]. However, the effect of human body on the impedance and efficiency of wearable antennas was not always presented [12, 13]. Printed wearable antennas have been presented in the last 10 years [1–20]. A review of wearable antennas designed and developed for several applications at different frequencies over the last 10 years is listed [15]. Wearable meander line antennas are presented in [12]. These antennas function in the frequency range between 750 and 2600 MHz. A textile antenna performance near human body is presented at 2.4 GHz, see [13]. The effect of human body on

portable RF antennas is studied in [16]. In this chapter, the authors determine that the antennas' length in free space is larger by 10–20% from the length of wearable antennas. Measurement of the antenna gain in this paper shows that a wide dipole (1.16 0.1 m) has 13 dBi gain. Wearable antennas for cellular applications are presented in [12–16]. Electrical specifications of medical devices are different from the electrical specifications for cellular devices. Medical wearable sensors are presented in [21–48]. Wearable devices support the development of personal medical sensors and systems with real-time response to help improve patient's health. Wearable medical sensors and devices can measure the sweat rate, body temperature, heartbeat, and blood pressure, perform gait analysis, and measure other body health parameters of the patient wearing these sensors, see Refs. [21–49]. In this chapter, novel wideband compact wearable antennas for 5G communication and medical systems are presented. Numerical results in free space and near the human body are presented.

determines the antenna bandwidth. However, thinner antennas are flexible. The antenna dimensions are designed to operate on the patient's body by using electromagnetic software [50]. The double-layer antenna is shown in **Figure 1**. The direc-

A double-layer 460 MHz dipole antenna is shown in **Figure 3**. The antenna dimensions are 20 4 cm. The directivity of the antenna at 460 MHz is around 5

tivity of the antenna at 420 MHz is around 4 dBi as shown in **Figure 2**.

*Wideband Wearable Antennas for 5G, IoT, and Medical Applications*

*DOI: http://dx.doi.org/10.5772/intechopen.93492*

dBi as presented in **Figure 4**. The antenna beamwidth is around 120°.

*Wearable double-layer 420 MHz printed dipole antenna.*

*Radiation pattern of a wearable double-layer printed dipole antenna.*

*Wearable double-layer 460 MHz printed dipole antenna.*

**Figure 1.**

**Figure 2.**

**Figure 3.**

**23**
