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access icon free Cylindrical near-field assessment of wearable antennas for body-centric communications

© The Institution of Engineering and Technology
Received 02/08/2016, Accepted 29/12/2016, Revised 02/12/2016, Published 02/01/2017

In this study, a measurement methodology is proposed for characterising wearable antennas on different locations of the human body. With the conventional roll-over-azimuth far-field system, it is impractical to capture the full spherical radiation pattern. A cylindrical near-field (CNF) technique is employed here which facilitates wearable antenna measurements on a solid full-body anthropomorphic phantom and readily produces the antenna radiation efficiency. The installed antenna efficiency is an important parameter for optimising a wearable system design and improving channel performance. The procedure of the CNF measurement is validated using a printed dipole antenna as a reference in horizontal and vertical polarisation parallel to body surface. Two textile wearable antennas with distinct radiation characteristics are designed, fabricated and assessed on the body phantom to operate at 2.4 GHz ISM band. Near-field and transformed far-field measurement results are presented and compared with electromagnetic simulations in order to demonstrate the benefits of the proposed measurement method.

Inspec keywords: textile products; microstrip antennas; antenna radiation patterns; dipole antennas; wearable antennas

Other keywords: cylindrical near-field technique; solid full-body anthropomorphic phantom; ISM band; full spherical radiation pattern; CNF measurement; printed dipole antenna; antenna radiation efficiency; textile wearable antennas; frequency 2.4 GHz; body-centric communications

Subjects: Single antennas

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