This paper presents electromagnetic encoders useful for chipless-RFID and motion control applications. The encoders consist in a pair of linear chains of rectangular apertures implemented by means of 3D printing. One of these chains is periodic and acts as a clock, whereas the other chain contains an identification (ID) code. With these two aperture chains, the ID code can be synchronously read, so that the relative velocity between the tag and the reader is irrelevant. Additionally, it is shown in the paper that by properly designing the reader, it is possible to determine the motion direction. The sensitive part of the reader is a microstrip line loaded with three complementary split ring resonators (CSRRs) etched in the ground plane and fed by three harmonic signals. By encoder motion, the characteristics of the local medium surrounding the CSRRs are modified, and the harmonic signals are amplitude modulated (AM) at the output port of the line, thereby providing the clock signal (which gives the encoder velocity), the ID code (providing also the quasi-absolute position) and the direction of motion. A fabricated prototype encoder is characterized by reading it with a dedicated reader.

中文翻译：

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用于无芯片RFID和运动控制应用的3D打印准绝对电磁编码器

本文介绍了适用于无芯片RFID和运动控制应用的电磁编码器。编码器由一对通过3D打印实现的矩形孔的线性链组成。这些链中的一条是周期性的，并充当时钟，而另一条链包含标识（ID）代码。通过这两个光圈链，可以同步读取ID码，因此标签和读取器之间的相对速度无关紧要。此外，论文显示，通过正确设计阅读器，可以确定运动方向。读取器的敏感部分是一条微带线，该微带线装有三个在接地平面上蚀刻并由三个谐波信号馈入的互补开口环谐振器（CSRR）。通过编码器运动，修改CSRR周围的本地介质的特性，并在线路的输出端口处对谐波信号进行幅度调制（AM），从而提供时钟信号（给出编码器速度），ID码（还提供准绝对位置）和运动方向。预制的原型编码器的特征在于使用专用的读取器进行读取。