摘要:工程结构物体随着时间的推移由于自身以及环境因素会产生裂纹, 裂纹一般来说都很小, 并不容易被检测到;当裂纹被检测到时, 一般来讲一经产生了严重的问题, 甚至接近临界尺寸, 危及结构安全. 由于裂纹主要产生在结构的应变集中处, 所以对敏感区域或则易损区域进行监测可以作裂纹萌生的表征. 传统∣的应变测量技术∣很难满足∣长时间、低成本、快速检∣测等要求. 由于传统应变器存在这些问题,本文对基于微带天线的应变测量技术进行理论研究和实验证明. 微带天线的中心频率与自身尺寸有关: 当它发生变形时, 中心频率会发生相应的偏移. 因此, 可利用微∣带天线中心频∣率的变化来反应物体发∣生的形变。52790
. 本文通过设计仿真以及进行试验测试来探究基于微带天线的应变测量技术, 同时研究其影响因素.将天线焊接在铝板上, 并在旅伴中间添加重物, 进行应变测量实验. 通过∣矢量网络分析仪来∣得到回波损耗曲线图,并进行分析, 再获得∣应变与微带天线频∣率偏移的关系. 分析结∣果显示, 应变∣与中心频∣率偏移之间存在近∣似线性关系, 可利∣用微∣带天线测量应变。
毕业论文关键词:传感器;RFID天线;结构测量
Abstra∣ct:the stru∣cture saf∣ety∣. Because∣ of∣ the crack is mainly∣ produced in the structure of ∣the strain concentration, ∣so the "crit∣ical areas" of the strain monitoring can∣ be used as a ∣sign of crack∣ initiation. Traditional strain measurement technique is very difficult to meet for a long time, low cost, fast detection, etc. To overcome the ∣shortcomings of the∣ traditional strain sensor∣, in this paper, based on the strain∣ measurement technology has carried on the feasibility of micros trip∣ antenna∣. The center frequency of a microstrip antenna is associated with its size: when its deformation, the center frequency and the corresponding shift happens. Therefore, available to characterize the strain microstrip antenna center frequency changes. In this paper, design and production of the four different size of the microstrip antenna, to explore the strain measurement technology based on microstrip antenna, and study the influencing factors. Attaching the antenna on the cantilever beam, and free in cantilever end applied load, strain measurement experiment. Return loss 11 S curve is obtained by vector network analyzer, and access to strain the relationship between the frequency deviation and the microstrip antenna. The analysis results show that approximate linear relationship between strain and the center frequency∣ deviation and micro strip antenna avai∣lable to mea∣sure∣ the strain.
Key words: RFID antenna;sensors;Structure of∣ the mea∣suring
目 录
1 引言 1
1.1 RFID的背景和意义 1
1.2 阻尼器概述 1
1.3 RFID系统概述 2
1.4 RFID应变器概述 2
1.5 国内外发展的现况 3
2 RFID天线基础 5
2.1 天线基本理论 5
2.1.1 电磁波产生的原理 5
2.1.2天线原理 5
2.1.3 RFID天线分类 6
2.1.4 天线的组成 6
2.2 天线基本参数 7
2.2.1 输入阻抗 7