適用於人體區域網路之小型化超寬頻天線設計

Abstract

本論文研究設計一支可運用於人體區域網路(Body Area Network, BAN)中On-body通訊(發射天線與接收天線皆配戴於人體上)之小型化超寬頻(Ultrawideband, UWB)天線。 在On-body通訊情境下，使用者身體會對天線特性造成很大的影響，過去使用之平面天線貼於人體時，無論該天線原來在自由空間場型為何，由於受到人體影響，最終會成為主波束朝向人體外發射的方向性場型，而非朝向On-body通訊中配戴於人體上的接收天線，如此電波將依賴附近散射體的反射波傳播，造成很高之路徑損耗(Path loss)，且通道特性也容易受到環境影響。

因此本論文提出一符合IEEE802.15.6(人體區域網路標準)協定下超寬頻upper band(6.2 – 10 GHz)之金屬架構，由於有特別設計的窄寬度，因此可以裝置在無線元件之側邊。使天線主波束朝向身體表面，因此大部分的能量可以透過直接波或繞射波有效的傳送至接收天線，進而大幅改善On-body通訊效能，且純金屬結構也有助於實做上與裝置側殼做結合。本天線的設計細節與實驗結果在論文中有詳細討論。

In this thesis, we propose a copper structure contain 6.2-10 GHz ultra wide band for involving on-body wireless body area network.

When develop the use of on-body communication devices, the human body can exert a strong influence on the characteristics of the antennas used in the devices. As previous study, when a planar antenna is set parallel on the body surface, the .body will alter the radiation pattern. Finally, the resultant pattern will be directional. With main bean is oriented away from the body. Therefore, most of the electromagnetic energy is radiated away from the body, so the propagation between the on-body antennas is depend on the reflected wave by scatterers nearby, lead to highly path loss.

The proposed antenna is designed with a very narrow width, can be mounted on the side of the wireless device. As this side-mounted structure is set on the human body, the electromagnetic energy can transmitted by direct wave, increase the whole efficiency. The details of antenna design and the experimental result are discussed is discussed in this thesis.