為了解決RFID晶片特性量測之問題，本論文提出一種簡單、快速且僅需一台網路分析儀，即可測得RFID晶片在讀取或寫入時的阻抗，以及其最低觸發功率等參數的近似值；取得這些參數後，設計RFID標籤的人員，即可事先估測所設計之標籤實作後的最大讀取距離；因此，可大幅降低實作的成本與縮短開發設計的時程。除了RFID晶片特性量測方法外，本論文中還提出一種RFID標籤阻抗匹配的量測與驗證方法，可直接量測晶片與天線組裝後的阻抗匹配程度，同時，還可判別出實部與虛部不匹配的程度和差異，提供設計者精確的修改方向，減少重覆設計、實作與量測的開發週期；此外，驗證量測所得之數據，可用以推算不同組裝條件下所造成的組裝誤差，藉此修正RFID晶片的等效模型，讓設計者可精準的設計出組裝後的天線與晶片可達到共軛匹配條件，確保設計的RFID標籤可發揮其最大的功效。

在金屬用RFID標籤的設計上，本論文中以鋼鐵廠的應用需求為對象，提出一系列用於設計直接貼附式RFID金屬標籤的結構與方法，包括：薄形化、小型化與長讀取距離的貼附式金屬標籤設計；對於以吊掛式鐵片標籤牌為主的應用，利用不同的耦合原理，亦提出一系列的鐵片RFID標籤牌的結構與設計方法，包括：直接饋入式的槽孔天線、電感耦合式以及間接耦合式的鐵片RFID標籤設計。所提出的兩系列RFID金屬標籤之設計，可含蓋大部份鋼鐵廠的實際應用需求，解決RFID技術在金屬環境應用的瓶頸。

A measurement method for characterizing RFID chip has been proposed that can measure the approximate Read/Write threshold power and impedance of RFID strap with minimum operating procedures; furthermore, the complicated RF facilities are not required. Obtaining the specifications of RFID strap allows designers to estimate maximum read range of designed RFID tag in advance. Therefore, the implemented cost and design cycle times can be reduced substantially. For the verification of the final match condition of assembled RFID tag, a direct measurement technique has been developed, which not only can verify the final impedance match condition of the assembled RFID tags, but can also be used to identify the resistance and reactance mismatch condition between the RFID chip and antenna. The measurement data obtained from the verification method can also be used to estimate the assembly error introduced by different mounting methods. The use of the corrected circuit model of the RFID chip impedance, which includes the assembly error, helps improve the accuracy of the RFID tag design. In the RFID metal tag design, a series of low profile and miniature RFID tags, which is directly attached on metallic objects, has been developed. A series of low cost and easily produced RFID tag antenna structures also has been realized for RFID application on hanging metallic tag, which makes the RFID solution well suited for metallic tag of labeling system that requires integration of RFID technology. The attached RFID metal tag and the metallic RFID hanging tag cover most of the RFID application on steel products in the steel industry.

1. Introduction 1
2. Measurement Method for Characterizing RFID Strap 4
2.1 Conventional Source-Pull System 4
2.2 Single-Ended Probe Method 6
2.3 Enhanced RFID Source-Pull System 11
2.4 Measurement Results 15
3. A Measurement Technique for Verifying The Match Condition of RFID Tags 22
3.1 Verification Method for An Assembled RFID Tag 23
3.2 Setup of RF Output Power of The Measurement Equipment 28
3.3 Corrected Circuit Model of RFID Chip 30
3.4 Simulation and Measurement Results 32
4. RFID Tag Design for Attaching on Metallic Objects 44
4.1 Double-Mushroom Tag 45
4.2 Double-Mushroom with Capacitive Load Bar 51
4.3 Double-Mushroom with an Inner Conductive Layer 55
4.4 Double-Mushroom in Bowtie-Shaped 60
5. RFID Tag Design for Hanging Metallic Tag Applications 65
5.1 A Y-Y-Shaped Slot Antenna 66
5.2 A Multi-Feed Y-Shaped Slot Antenna 70
5.3 An Inductively Coupling Metallic Tag Antenna 76
5.4 A Miniature and Near-3D Omni-Directional Metallic Tag Antenna 88
5.5 A Multi-Feed and Near-3D Omni-directional Metallic Tag Antenna 93
5.6 A Small Dipole Coupling Metallic Tag Antenna 97
6. Conclusions 102
6.1 Summary 102
6.2 Future Research 106
APPENDIX I 108
APPENDIX II 109

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