||Optimum Wireless Powering Design for the Applications of Wireless Biotelemetry Systems
||Department of Electrical Engineering
medical implant communication service (MICS) band
microelectromechanical systems (MEMS)
application-specific integrated circuit (ASIC)
最後將此兩種無線充電電路與傳能系統在接近人體組織的情況下進行驗證與測試其可行性。無線充電系統中，在10-dBm 輸入射頻功率與電池可充電的電壓區間內 (3.7 to 4.2 V) 條件下，可以達到高於百分之75%的射頻轉直流的轉換效能且可涵蓋90%的充電期。同時，在功率傳輸距離50 cm還可有76.2 % 的充電效能。在無線傳能系統中，利用TSMC 0.18-um製程製作特定應用之積體電路，其占據面積為500 um × 780 um，同時與微型天線整合進行無線功率傳送效能的量化。實驗結果指出在輸入功率+9 dBm與3.5 kΩ的負載之下，其最佳化的整流電路可以產生2.94 V的輸出電壓與31%的轉換效能。根據在傳輸距離4 cm、傳輸功率+32 dBm以及被摘除豬眼球組織的組合條件下，步階式環狀天線與偶極天線分別可以產生出2.01 mW 與 1.2 mW 的輸出直流功率。重要的是此研究驗證了最佳化的微型整流天線設計的可行性與克服在眼球組織上的功率損耗達到增加傳送距離與縮減傳遞功率的能力。
The bio-telemetry system has received considerable attention recently for its high accuracy, long-term availability and convenience. To achieve the goal of data capture and health monitoring through high dielectric constant of human tissue, generating sufficient electrical power by harvesting RF energy for wireless powered portable and wearable monitoring devices has been an important issue. In general, wireless battery charging and real-time wireless powering were often used in the far-field application where efficiency is the dominant factor of its performance. Thus, this thesis proposed two methods to improve the efficiency of far-field wireless charging/powering system.
In wireless charging system, a DC current driving impedance matching method is proposed for rectennas for the wireless charging of implantable lithium-ion (Li-ion) rechargeable batteries using the medical implant communication service (MICS) band. Unlike the traditional method, which uses only the direct-current (DC) resistive load or battery potential, the proposed method adopts the output DC current of the dual-diode rectifiers to establish a simple equivalent model for wireless battery charging. Using this model, the optimized impedance matching network of the rectenna is derived to maximize efficiency within the charging range of a Li-ion battery. As to real-time wireless powering system, a prototype of miniaturized rectifying antenna (rectenna) design is presented for the wireless powering of ocular device. In contrast to the conventional on-lens loop antenna, two types of miniaturization antennas - a stepped-loop antenna and a stepped-dipole antenna - on the substrate of a transparent contact lens, which are based on micro-electromechanical systems (MEMS) technology, are designed for use on ocular tissue and their electromagnetic characteristics are analyzed. Additionally, the RF rectifier and voltage-boosting network (VBN) are optimized to enhance the power conversion efficiency (PCE) by using the voltage boosting technique.
Finally, the two forms of wireless charging/powering system were tested under physiological conditions to verify their reliability. For a 10-dBm input radio-frequency (RF) power in the wireless charging system, the RF-to-DC conversion efficiency is higher than 75% in the potential range of 3.7 to 4.2 V, which is the range used for over 90% of the charging duration. The best battery charging efficiency was 76.2% at a transmission distance of 50 cm. As to the powering harvester ASIC in the real-time wireless powering system which was fabricated using a TSMC 0.18-um process, it occupied an area of 500 um × 780 um and integrated with miniaturized antennas to quantify the effectiveness of wireless power transfer. Experimental results indicate that the optimal rectifier produces a DC output voltage of 2.94 V and a conversion efficiency of 31% across a resistive 3.5 kΩ load with an input power of +9 dBm. According to the measurements made, the stepped-loop and stepped-dipole rectennas generate 2.01 mW and 1.2 mW of output DC power, respectively, at a distance of 4 cm and a transmitting power of +32 dBm under an enucleated porcine eye. Importantly, this work demonstrates the feasibility of an optimal miniaturized on-lens rectenna design, capable of overcoming the RF power attenuation on the ocular tissue to increase the delivering distance and reduce the transmitting power.
List of Figures X
List of Table XIII
Chapter 1. Introduction 1
1.1 Literature of Wireless Charging /Powering 1
1.1.1 Wireless Charging Battery 1
1.1.2 Real-Time Wireless Powering 4
1.2 Motivation 8
Chapter 2. Design of Wireless Powering/Changing System 10
2.1 Field Boundary 10
2.2 Wireless Battery Charging System 12
2.2.1 Overview of Wireless Battery Charging 12
2.2.2 Rectifier Modeling and Design 13
2.2.3 Voltage Boosting Network (VBN) Design 17
2.2.4 Implantable Rectenna Design 22
2.3 On-lens Wireless Powering on Enucleated Porcine Eyes 24
2.3.1 Overview of On-lens Wireless Powering 24
2.3.2 Contact lens of character and Microfabrication 25
2.3.3 Design of a Stepped Loop Rectenna 26
2.3.4 Impedance Matching Network and Rectifier Design 31
Chapter 3. Experiment and Results 41
3.1 Setup of Wireless Battery Charging 41
3.2 Results of Wireless Battery Charging 42
3.3 Setup of Real-time Wireless Powering 46
3.4 Results of Real-time Wireless powering 49
3.5 Safety Code 55
Chapter 4. Conclusion and Future Work 57
 S. J. A. Majerus, P. C. Fletter, M. S. Damaser, and S. L. Garverick, "Low-Power Wireless Micromanometer System for Acute and Chronic Bladder-Pressure Monitoring," IEEE Transactions on Biomedical Engineering, vol. 58, pp. 763-767, 2011.
 S. Y. Lee, C. H. Hsieh, and C. G. M. Yang, "Wireless Front-End With Power Management for an Implantable Cardiac Microstimulator," IEEE Transation on Biomedical Circuits and Systems, vol. 6, pp. 28-38, 2012.
 Y. T. Liao, H. Yao, A. Lingley, B. Parviz, and B. P. Otis, "A 3-uW CMOS Glucose Sensor for Wireless Contact-Lens Tear Glucose Monitoring," IEEE Journal of Solid-State Circuits, vol. 47, pp. 335-344, 2012.
 H. Miranda, V. Gilja, C. A. Chestek, K. V. Shenoy, and T. H. Meng, "HermesD: A High-Rate Long-Range Wireless Transmission System for Simultaneous Multichannel Neural Recording Applications," IEEE Transation on Biomedical Circuits and Systems, vol. 4, pp. 181-191, 2010.
 D. M. Spillman and E. S. Takeuchi, "Lithium ion batteries for medical devices," in Battery Conference on Applications and Advances, Long Beach, CA, 1999, pp. 203-208.
 V. L. Teofilo, L. V. Merritt, and R. P. Hollandsworth, "Advanced lithium ion battery charger," in Battery Conference on Applications and Advances, Long Beach, CA, 1997, pp. 227-231.
 R. S. Rubino, H. Gan, and E. S. Takeuchi, "Implantable medical applications of lithium-ion technology," Battery Conference on Applications and Advances, 2002.
 B. D. Valle, C. T. Wentz, and R. Sarpeshkar, "An Area and Power-Efﬁcient Analog Li-Ion Battery Charger Circuit," IEEE Transation on Biomedical Circuits and Systems, vol. 5, 2011.
 L. Pengfei and B. Rizwan, "A Wireless Power Interface for Rechargeable Battery Operated Medical Implants," IEEE Transation on Circuits and Systems--II: Express Briefs, vol. 54, pp. 912-916, 2007.
 W. S. Yeoh, W. S. T. Rowe, and K. L. Wong, "Decoupled dual-dipole rectennas on a conducting surface at 2.4 GHz for wireless battery charging," IET Microwaves, Antennas & Propagation, vol. 6, pp. 238-244, 2011.
 E. Y. Chow, C. L. Yang, and W. J. Chappell, "Wireless Powering and the Study of RF Propagation Through Ocular Tissue for Development of Implantable Sensors," IEEE Transactions on Antennas and Propagation, vol. 59, pp. 2379-2387, 2011.
 S. D. Smedt, A. Mermoud, and C. Schnyder, "24-hour intraocular pressure fluctuation monitoring using an ocular telemetry Sensor: tolerability and functionality in healthy subjects," J. Glaucoma, vol. 8, pp. 539-544, 2012.
 P. Auvray, L. Rousseau, G. Lissorgues, F. Soulier, O. Potin, S. Bernard, F. Dieuleveult, E. Scorsone, P. Bergonzo, L. Chicaud, and S. Picaud, "A passive pressure sensor for continuously measuring the intraocular pressure in glaucomatous patients," IRMB, pp. 117-122, 2012.
 H. Yao, A. J. Shum, M. Cowan, I. Lähdesmäki, and B. A. Parviz, "A contact lens with embedded sensor for monitoring tear glucose level," Biosensors and Bioelectronics, vol. 7, pp. 3290–3296, 2011.
 K. Gosalia, M. S. Humayun, and G. Lazzi, "Impedance Matching and Implementation of Planar Space-Filling Dipoles as Intraocular Implanted Antennas in a Retinal Prosthesis," IEEE Transaction on Antenna and Propagation, vol. 8, pp. 2365-2373, 2005.
 H. Permana, Q. Fang, and S. Y. Lee, "Comparison study on specific absorption rate of three implantable antennas designed for retinal prosthesis systems," IET Microwaves, Antennas & Propagation, vol. 7, pp. 886-893, 2012.
 K. Gosalia, M. S. Humayun, and G. Lazzi, "Impedance Matching and Implementation of Planar Space-Filling Dipoles as Intraocular Implanted Antennas in a Retinal Prosthesis," IEEE Transation on Aantennas and Prpgration, vol. 53, pp. 2365-2373, 2005.
 T. B. Tang, S. Smith, B. W. Flynn, J. T. M. Stevenson, A. M. Gundlach, H. M. Reekie, A. F. Murray, D. Renshaw, B. Dhillon, A. Ohtori, Y. Inoue, J. G. Terry, and A. J. Walton, "Implementation of wireless power transfer and communications for an implantable ocular drug delivery system," IET Nanobiotechnology, vol. 2, pp. 72-79, 2008.
 E. Y. Chow, C. L. Yang, A. Chlebowski, S. Moon, W. J. Chappell, and P. P. Irazoqui, "Implantable Wireless Telemetry Boards for In Vivo Transocular Transmission," IEEE Transation on Microwave Theory and Techniques, vol. 56, pp. 3200-3208, 2008.
 J. Pandey, Y. T. Liao, A. Lingley, R. Mirjalili, B. Parviz, and B. P. Otis, "A Fully Integrated RF-Powered Contact Lens With a Single Element Display," IEEE Transactions on Biomedical Circuits and System, vol. 4, pp. 454-460, 2010.
 P. J. C. A. S. S. R. Varma, M. S. Humayun, and Y. C. Tai, "Wireless Intraocular Pressure Sensing Using Microfabricated Minimally Invasive Flexible-Coiled LC Sensor Implant," Journal of Microelectromechanical System, vol. 4, pp. 721-734, 2010.
 A. R. Lingley, M. Ali, Y. Liao, R. Mirjalili, M. Klonner, M. Sopanen, S. Suihkonen, T. Shen, B. P. Otis, H. Lipsanen, and B. A. Parviz, "A single-pixel wireless contact lens display," Journal of Micromechanics and Microengineering, vol. 21, pp. 125014-125022, 2011.
 A. Shameli, A. Safarian, A. Rofougaran, M. Rofougaran, and F. D. Flaviis, "Power Harvester Design for Passive UHF RFID Tag Using a Voltage Boosting Technique," IEEE Transation on Microwave Theory and Techniques, vol. 55, pp. 1089-1097, 2007.
 G. D. Vita and G. Iannaccone, "Design Criteria for the RF Section of UHF and Microwave Passive RFID Transponders," IEEE Transation on Microwave Theory and Techniques, vol. 53, pp. 2978-2990, 2005.
 F. J. Huang, C. M. Lee, C. L. Chang, L. K. Chen, T. C. Yo, and C. H. Luo, "Rectenna application of miniaturized implantable antenna design for triple-band biotelemetry communication," IEEE Transation on Aantennas and Prpgration, vol. 59, pp. 2646-2653, 2011.
 S. K. H. T. C. Chou and B. J. Hwang, "Effect of cathode structure on cell performance in wireless charging process," Journal of Power Sources, vol. 146, pp. 606-610, 2005.
 N. Carrara. (2012). Dielectric properties of body tissues at Italian National Research Council, Institute of Applied Physics (IFAC). Available: http://niremf.ifac.cnr.it/tissprop/htmlclie/htmlclie.htm
 M. Leonardi, E. M. Pitchon, A. Bertsch, P. Renaud, and A. Mermoud, "Wireless contact lens sensor for intraocular pressure monitoring: assessment on enucleated pig eyes," Acta Ophthalmologica, vol. 87, pp. 433-437, 2009.
 H. W. C. B. M. Jeng, C. Y. Chen, H. Y. Huang, J. C. Chiou, and C. H. Luo, "The Rectenna Design on Contact Lens for Wireless Powering of the Active Intraocular Pressure Monitoring System " in IEEE Int. Conf. Engineering in Medicine and Biology Society, Japan, 2013, pp. 2447-3450.
 M. T. W. M. L. Chuang, "Application of Transmission-Line Model to Dual-Band Stepped Monopole Antenna Designing," Antennas and Wireless Propagation Letters, vol. 10, pp. 1449-1452, 2011.
 J. Kim and Y. Rahmat-Samii, "Implanted antennas inside a human body: simulations, designs, and characterizations," IEEE Transation on Microwave Theory and Techniques, vol. 8, pp. 1934-1943, 2004.
 "IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3KHz to 300 GHz," ed: IEEE Standard C95.1-2005, 2005.
 A. M. S. Bagga and W. Serdijn, "A High Efﬁciency Orthogonally Switching Passive Charge Pump Rectiﬁer for Energy Harvesters," IEEE Transation on Circuits and Systems--I: Regular Papers, vol. 60, pp. 1959-1966, 2013.
 C. L. C. K. H. Chen and S. T. Liu, "Efﬁciency-enhanced CMOS rectiﬁer for wireless telemetry," Electronics Letters, vol. 18, pp. 976-978, 2007.
 C. Ma, T. U. Beijing, C. Zhang, and Z. Wang, "A Low-Power AC/DC Rectifier for Passive UHF RFID Transponders," in IEEE Int. Conf. Microwave Antenna Propagation, Hangzhou, 2007, pp. 309-314.
 C. M. L. T. C. Yo, C. M. Hsu, and C. H. Luo, "Compact circularly polarized rectenna with unbalanced circular slots," IEEE Transation on Aantennas and Prpgration, vol. 56, pp. 882–886, 2008.
 Y. H. Suh and K. Chang, "A High-Efficiency Dual-Frequency Rectenna for 2.45- and 5.8-GHz Wireless Power Transmission," IEEE Transation on Microwave Theory and Techniques, vol. 50, pp. 1784–1789, 2002.
 H.Takhedmit, L.Cirio, B. Merabet, B. Allard, F. Costa, C. Vollaire, and O. Picon., "Efﬁcient 2.45 GHz rectenna design including harmonic rejecting rectiﬁer device," Electronics Letters., pp. 811-812, 2010.
 Y. G. H. J. P. McCully and H. Alizadeh, "A pig model of acanthamoeba keratitis:transmission via contaminated contact lenses," Invest Ophthalmol Vis Sci., vol. 54, pp. 595-973, 1992.
 M. Leonardi, E. M. Pitchon, A. Bertsch, P. Renaud, and A. Mermoud, "Wireless contact lens sensor for intraocular pressure monitoring: assessment on enucleated pig eyes," Acta Ophthalmologica, vol. 87, pp. 433-437, , 2009.
 E. Vecino and S. C. Sharma. (2011). Glaucoma Basic and Clinical Concepts.
 E. Y. Chow, L. Chlebowski, and P. P. Irazoqui, "A Miniature-Implantable RF-Wireless Active Glaucoma Intraocular Pressure Monitor," IEEE Trans Biomed Circuits System, vol. 6, pp. 340-349, 2010.
 M. H. Ouda, M. Arsalan, L. Marnat, A. Shamim, and K. N. Salama, "5.2-GHz RF Power Harvester in 0.18-um CMOS for Implantable Intraocular Pressure Monitoring," IEEE Transation on Microwave Theory and Techniques, vol. 61, pp. 2177-2184, 2013.