الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Antennas must have certain features and properties to be considered wearable, where they can be placed anywhere on the body, such as the wrist, chest, back, thigh, and abdomen, depending on the application. Flexibility, compact size, high gain, low Specific Absorption Rate (SAR), and a unidirectional radiation pattern are examples of such characteristics. With that in mind, this thesis presents five design approaches for wearable antennas that are designed, fabricated, evaluated, and measured in free space and near the human body.
The goals of the various wearable design approaches are to introduce different unique single, dual and triple frequency bands with small wearable antenna profiles while maintaining high antenna gain and efficiency and low SAR. Through the fabrication process, all reported designs have been fabricated using textile Felt substrate and ShieldIt conductive material to demonstrate the flexibility features needed for the wearable biomedical antennas.
For the single frequency band; two textile-based wearable-inspired folded dipole antenna FDAs fed by the Co-Planar Waveguide (CPW). Both antennas were evaluated in free space and the human body.
The first antenna is designed to operate at ISM 2.45 GHz and mounted on the human’s chest for monitoring the heart rate and respiratory rate of the patient unceasingly. The antenna was spaced by 10 mm from the human chest, where performance parameters; such as, realized gain, total efficiency, and SAR were analyzed; thus, leading to the optimum performance. While the second one was designed by modifying the first antenna to be operating at 2.4 GHz and backed by a textile-based 2 × 4 Artificial Magnetic Conductor (AMC) array structure that is placed on the surgical mask covering the patient’s mouth to detect the viral disease (flu/influenza) by analyzing the patient’s breath.
Second, a dual-band textile CPW monopole E-shaped antenna that works at 2.4 GHz and 5.8 GHz for wearable medical applications to monitor the heartbeat was designed. The antenna is integrated with a 4 × 4 dual-band textile AMC reflector to enhance the gain and specific absorption rate (SAR). The total design size is 98.65 mm × 98.65 mm. The SAR is reduced by nearly 95% at both 1 and 10 g. Afterward, further enhancement of dual-band antenna properties in terms of size was attained by designing an F-shaped antenna as the second antenna radiator. where the antenna was backed by an all textile 3 × 3 AMC to enhance the gain and reduce the SAR. To become the total system size of 74.2 mm × 74.2 mm.
Third, a triple-band antenna was designed to operate at the required frequencies of 2.4 GHz for ISM, 3.5 GHz for WLAN, and 5.8 GHz for the WiMAX applications. To minimize electromagnetic radiation inside the human body, enhance gain, and reduce SAR, the all-textile 2 × 3 array AMC array was incorporated with a total size of 75 mm × 50 mm to enhance the antenna gain and efficiency, as well as, reduce SAR levels.