We recently reported a new class of broadband and high gain antennas for into-body radiation, called Bio-Matched Antennas (BMAs). A major limitation of our prior work is that BMA volume increases significantly as the low cutoff frequency is reduced. This is particularly troublesome for into-body applications where low operating frequencies are needed to penetrate deep into the tissues. Here, we overcome this challenge via a novel design that extends the BMA’s conducting flares along the tissue surface. In doing so, the antenna’s lowest operating frequency is reduced, while its volume remains unaltered. For an example BMA of 1161.3 mm ³ in volume, our new approach results in lowering the cutoff frequency from 1.9 GHz to 830 MHz. Additional novelties brought forward include: (a) the first testing of BMAs through stratified tissue models (as opposed to homogeneous models explored in the past), and (b) the smallest volume BMA reported to date, which also exhibits the lowest frequency cutoff as well as comparable or better transmission loss vs. previous designs.

中文翻译：

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具有火炬扩展功能的生物匹配天线，可减少低频截止

我们最近报告了一种用于人体辐射的新型宽带和高增益天线，称为生物匹配天线（BMA）。我们先前工作的一个主要限制是，随着低截止频率的降低，BMA的体积会显着增加。对于需要低工作频率来深入组织的体内应用而言，这尤其麻烦。在这里，我们通过一种新颖的设计克服了这一挑战，该设计将BMA的导电光斑沿组织表面延伸。这样做可以降低天线的最低工作频率，而其体积却保持不变。例如1161.3 mm ^3的BMA 在数量上，我们的新方法可将截止频率从1.9 GHz降低至830 MHz。提出的其他新颖性包括：（a）通过分层组织模型进行BMA的首次测试（与过去探索的同质模型相对），以及（b）迄今为止报道的最小BMA体积，其频率截止值最低与以前的设计相比，传输损耗相当或更好。