S11 parameter measurement

A frequency dual polarized compact implantable antenna is designed and presented in this paper. The proposed circular antenna occupies a compact volume of 9.46 mm3 . To achieve frequency reconfigurability, the antenna uses switching configuration of PIN diodes and it operates at 1.395–1.432 GHz Wireless Medical Telemetry Service (WMTS) band and 2.4–2.48 GHz Industrial, Scientific, and Medical (ISM) band. Another feature of this antenna is its dual polarization capability, which allows it to operate at 1.4 GHz with Linear Polarization (LP) and 2.4 GHz with Right Hand Circular Polarization (RHCP).When compared to a conventional antenna, the proposed antenna design reduces size by approximately 88.6% for feed1 and 80.66% for feed2. Peak gains for the antenna are -31 dB at 1.4 GHz and -28 dBic at 2.41 GHz. The measured -10 dB bandwidths of the fabricated antenna are 11.48% and 6.81% at 1.4 GHz and 2.4 GHz respectively. The measured ARBW value at 2.4 GHz is 7.21%.

本文设计并提出一款紧凑型双频双极化植入式天线。所提出的圆形天线体积仅为9.46 mm³，尺寸极为紧凑。为实现频率可重构特性，该天线采用PIN二极管（PIN diode）开关配置，可分别工作于1.395–1.432 GHz无线医疗遥测服务（Wireless Medical Telemetry Service, WMTS）频段与2.4–2.48 GHz工业、科学与医疗（Industrial, Scientific, and Medical, ISM）频段。该天线另一核心特性为双极化能力：在1.4 GHz频段可工作于线极化（Linear Polarization, LP）模式，在2.4 GHz频段则可实现右旋圆极化（Right Hand Circular Polarization, RHCP）模式。相较于传统天线，本次提出的天线设计在馈电1处尺寸缩减约88.6%，在馈电2处缩减约80.66%。该天线的峰值增益分别为1.4 GHz时的-31 dB，与2.41 GHz时的-28 dBic。经实测，所制备的天线样机在1.4 GHz与2.4 GHz频段的-10 dB带宽分别为11.48%与6.81%。该天线在2.4 GHz频段的实测轴比带宽（Axial Ratio Bandwidth, ARBW）为7.21%。