Modern wireless devices operate on multiple frequency bands and, thus, can benefit from frequency-reconfigurable radio frequency (RF) components, especially filters that are typically larger in size and are required for every frequency band. In addition, many applications, such as wearable electronics, desire stable performance from the devices when they are bent or flexed. However, most of the reconfigurable filters are built on rigid substrates and utilize expensive discrete RF switches, which needs to be soldered to the filters. In this work, we present a fully printed filter that achieves reconfigurability through printed vanadium dioxide (VO ₂ )-based switches that are extremely low cost and do not require any soldering for their attachment. The filter design is based on a dual-mode resonator, which enables a second-order filter despite a single resonator, thus helping in making the filter compact. It also helps in maintaining a decent insertion loss (2.6 dB), despite relatively low conductivity of the metallic ink. The switches, when activated thermally through a printed heater at the backside, reconfigure the frequency from 4 to 3.75 GHz. The filter has been realized on a flexible Kapton substrate, making the filter conformable to any surface. Measurements under various bending conditions reveal stable performance, making this filter design suitable for a number of wearable and the Internet-of-Things applications.

中文翻译：

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采用基于VO 2的开关的加法制造双模可重构滤波器

现代无线设备在多个频带上运行，因此可以受益于频率可重新配置的射频（RF）组件，尤其是通常尺寸较大且每个频带都需要的滤波器。此外，许多应用（例如可穿戴电子设备）都要求设备在弯曲或弯曲时具有稳定的性能。但是，大多数可重构滤波器都建立在刚性基板上，并使用昂贵的分立式RF开关，需要将其焊接到滤波器上。在这项工作中，我们介绍了一种完全印刷的过滤器，该过滤器可通过印刷的二​​氧化钒（VO ₂ ）的开关，成本极低，并且不需要任何焊接。滤波器设计基于双模谐振器，尽管有单个谐振器，该滤波器仍可实现二阶滤波器，从而有助于使滤波器紧凑。尽管金属油墨的电导率相对较低，但它也有助于保持良好的插入损耗（2.6 dB）。这些开关通过背面的印刷加热器进行热激活时，会将频率重新配置为4至3.75 GHz。该过滤器已在柔性Kapton基板上实现，使该过滤器适合任何表面。在各种弯曲条件下进行的测量显示出稳定的性能，从而使该滤波器设计适用于许多可穿戴和物联网应用。