Memristors for Low-Power, Passive RF Devices

摘要智能优势：自适应阻抗匹配使低成本混合天线具有动态波束形成能力，将提高无线通信性能。然而，现有方法存在一些挑战，包括：(i)混合天线中的固定阻抗限制了灵活性并阻止了动态波束形成；（ii）使用半导体进行阻抗开关有几个缺点。这些包括：(a)要求持有？晶体管在特定的状态下通过保持最小的激活电压导致其能量消耗的增加，并且(b)晶体管和半导体的非线性引入了偏置，这改变了天线接收到的强弱信号之间的有效阻抗。相比之下，本项目的目标是研究和设计一种新的射频前端设计方法，用忆阻器取代传统的基于cmos的阻抗开关。特别是，基于忆阻器的射频前端将用于无源RFID技术和混合天线设计。预期的贡献包括了解射频（RF）应用中忆阻器的性能，以及更灵活地设计天线阻抗匹配网络。这项工作的最终结果可能会导致天线和射频前端设备设计的变革范例。更广泛的影响：主要的建议成果是对如何将不同类型的忆阻器应用于RF系统的新知识和理解，例如用于弱信号的自适应天线阵列，以及阻抗匹配网络及其调谐的简化设计。这将使无源射频识别（RFID）系统中更便宜、更简单的波束形成混合天线的新设计成为可能。这些好处将适用于其他通信系统，如认知网络和雷达系统。一系列外展活动包括通过密苏里州学生多样性项目办公室吸引女性和少数族裔学生的参与，以及通过密苏里州夏季研究学院（SRA）项目吸引高中学生的K-12外展活动。从长远来看，该成果将支持通信系统中基于忆阻器的许多技术应用，包括可穿戴天线系统和传感器，并增强农村无线互联网接入系统的性能和覆盖范围，目前没有服务地区。

AbstractIntellectual Merit: Adaptive impedance matching enables development of low cost hybrid antennas with dynamic beamforming capabilities that will improve the performance of wireless communication. However, there are several challenges with existing approaches including: (i) fixed impedance in hybrid antennas restricts flexibility and prevents dynamic beamforming, (ii) employment of semiconductors for impedance switching has several drawbacks. These include: (a) requirement of ?holding? a transistor in a specific state by maintaining a minimum activation voltage leading to an increase in its energy consumption, and (b) nonlinearity of transistors and semiconductors introduce a bias, which changes the effective impedance between strong and weak signals received by an antenna. In contrast, the goal of this project is to study and design a novel approach to RF front-end design with memristors replacing traditional CMOS-based impedance switching. In particular, the memristor-based RF front ends will be employed in a passive RFID technology and hybrid antenna design. The expected contributions include understanding the performance of memristors in radio frequency (RF) applications, and more flexible design of impedance matching networks for antennas. The end result of this effort could lead to a transformative paradigm in designing antennas and RF front-end devices.Broader Impact: The main proposal outcomes are a new knowledge and understanding of how different type of memristors could be applied to RF systems such as adaptive antenna arrays for weak signals, and a simplified design of impedance matching networks and their tuning. This will enable new designs of cheaper and simpler beamforming hybrid antennas in passive radio frequency identification (RFID) systems. The benefits will apply to other communication systems such as cognitive networks and radar systems. A set of outreach activities include engagement of women and students from under-represented minorities through the Missouri S&T Student Diversity Programs office and K-12 outreach that engages high school students through the Missouri S&T Summer Research Academy (SRA) program. In the long term, the outcomes will support a number of memristor based technology applications in communication systems including wearable antenna systems and sensors, and enhancing performance and coverage of wireless Internet access systems for rural, currently-not-serviced areas.