In this letter, a single-antenna-based compact harmonic RFID tag having efficient power harvesting topology is demonstrated. The harmonic RFID receives a continuous signal at the fundamental frequency ( $fo = 434$ MHz) and replies back with modulation at the second harmonic ( $2fo = 868$ MHz). To enhance the read range, the harmonic RFID tag topology was designed to harvest energy simultaneously while performing modulation in a continuous mode. Furthermore, the harmonic RFID allows the use of lower modulation rates to reduce power consumption, thus further enhancing the read range. Performance at different modulation rates is demonstrated. Overall, a compact and efficient harmonic RFID is demonstrated with a read range of 8 m at a 1-kHz tag data modulation rate and 30-dBm transmit power.

中文翻译：

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一种连续模式单天线谐波 RFID 标签

在这封信中，展示了具有高效功率收集拓扑的基于单天线的紧凑型谐波 RFID 标签。谐波 RFID 接收基频的连续信号（ $fo = 434$ MHz) 并以二次谐波 ( $2fo = 868$ 兆赫）。为了提高读取范围，谐波 RFID 标签拓扑被设计为在以连续模式执行调制的同时收集能量。此外，谐波 RFID 允许使用较低的调制率来降低功耗，从而进一步提高读取范围。演示了不同调制速率下的性能。总体而言，在 1 kHz 标签数据调制速率和 30 dBm 发射功率下，具有 8 m 的读取范围展示了紧凑且高效的谐波 RFID。