Analysis of a Near Field Communication wireless power system
Analysis of a Near Field Communication wireless power system
复制标题
近场通信无线电力系统分析
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Joshua R. Smith
中科院分区：
文献类型：
--
作者：
Yi Zhao;Brody J. Mahoney;Joshua R. Smith
近场通信(NFC)阅读器无处不在地嵌入在智能手机、公共汽车和其他基础设施中，能够通过耦合磁场向超低功率、无源NFC标签无线提供毫瓦级的功率。此外，NFC读取器可以利用耦合的通信信道来支持相对繁重的计算应用，例如感测、视觉显示等。因此，需要在CM读取范围内具有稳健通信的可靠和高效的功率传输，以实现各种更苛刻的NFC-WISP应用。然而，在无线功率传输和谐振器带宽之间有一个基本的权衡，这对NFC通信至关重要。磁耦合系统的另一个共同特征是易受标签读取距离和天线未对准变化的影响。为了缓解这些挑战，我们提出了两个基于仿真的研究，以研究在考虑寄生效应的情况下，不同NFC读取范围下的功率传输和带宽性能。首先，在忽略交叉耦合影响的情况下，利用简化的仿真模型对两线圈和三线圈的NFC系统进行了理论分析比较。其次，我们用一个复杂的模型描述了三线圈系统的交叉耦合效应的影响。最后，我们演示了2线圈和3线圈系统中跨线圈的寄生电容的影响。
Near Field Communication (NFC) readers, ubiquitously embedded in smart-phones, buses and other infrastructures, are able to wirelessly deliver mW-level power to ultra-low power, passive NFC tags via a coupled magnetic field. Additionally, an NFC reader can leverage the coupled communication channel to support relatively heavy computational applications, such as sensing, visual displays, etc. Consequently, reliable and efficient power-transfer with robust communication in the cm reading range is required to enable various more demanding NFC-WISP applications. However, there is a fundamental tradeoff between wireless power delivery and resonator bandwidth, which are critical to NFC communication. Another common trait of magnetically coupled systems is the vulnerability to variations in tag reading distance and antenna misalignment. To mitigate these challenges, we present two simulation-based investigations to study the power transfer and bandwidth performance given different NFC reading range with consideration of parasitic effects. Firstly, we compare a 2-coil NFC system with a 3-coil NFC system via theoretical analysis utilizing a simplified simulation model by ignoring the cross-coupling effect. Secondly, we present the influence of cross-coupling effects of a 3-coil system using a complex model. Finally, we demonstrate the effect of parasitic capacitance across coils for both 2 and 3-coil systems.