由於微機電技術和超大型積體電路技術的提昇使得生醫工程研發人員已邁向植入式生醫診療電子系統這類前瞻性的研發。近年來，植入式遙測系統已經應用於動物實驗和人體訊號的量測，植入裝置的電源供可由透膚式磁場耦合獲得；使用外部發射線圈傳送電源及命令與植入裝置進行溝通，這種方法能避開傷口感染和電池電力竭盡的危險。本研究的目的在於發展以植入式微控制器為基礎實現具雙向資料傳輸的生醫微系統，經由電磁感應測量生理訊號。此系統由兩個部分所組成︰外部模組及植入模組。外部模組包含高效率Ｅ類放大器和資料復原解調器；Ｅ類放大器傳送電源及指令資料給植入模組，解調變電路將植入模組所傳送出來的生理訊號資料解調並傳送給個人電腦進行資料的處理。植入模組包含雙通道生物信號檢測及資料擷取；所檢測的訊號在經過放大、帶通濾波及數位化後傳送至外部。為了降低在檢測訊號時從載波頻率的磁場干擾，使用兩個分開獨立的線圈做為雙向傳輸時的資料傳遞。
　　我們已經成功地設計、實現與測試完成了可植入式雙向無線傳輸生醫微系統的所有的玏能。振幅移鍵控(ASK)調變用以輸入指令的傳送;資料傳出的方式為負載移鍵控(LSK)調變，此種調變允許透過同一個無線射頻電磁波傳輸能量及資料。所量測的訊號具有10位元解析度且最大傳輸速度可逹 115 kbps。植入量測裝置利用離散電子元件實現在 3x4.5 cm2 矩形雙面印刷電路板上消耗功率約為 90 mW。系統的電磁感應效率在距離 3.5 公分之內可維持在 25% 以上。此植入式裝置可以進行多種神經科學研究上的動物實驗。

　　The advances of microelectromechanical system (MEMS) and very large scale integration (VLSI) technologies have made biomedical researchers to gear their research activities toward the development of implantable biomedical electronic devices. Recently, the implantable telemetry systems have been used for animal experiments and human measurements. The implanted device can be powered by transcutaneous magnetic coupling, by using an external transmitter coil to power and commands communicate with the implanted device. This arrangement can avoid the risk of wound infection and the exhaustion of battery life. The aim of this study is to develop an implantable microcontroller-based bi-directional wireless transmission biomicrosystem through inductive link for the physiological signal measurement. The system consists of two sub-systems: the external and implantable module. The external module includes a high efficient class-E power transmitter and a data recovering demodulator which the transmitter transmits power and commands into the implant and the demodulator recovers the recorded physiological signal data from the implant and is connected to a PC for further data processing. Two channels of biological signal sensing and data acquisition are included in the implanted module. The recorded signals were amplified, bandpass filtered, and digitized for sending outwards. To reduce the electromagnetic interference from the carrier frequency while sensing, two coils are used separately in the implant for carrying out the two-way data transmission.
　　The amplitude-shift keying (ASK) modulation is used for inward command transmission. For outward transmission, a load-shift keying (LSK) approach which allows wireless power and data transmission through the same RF link. The sensed signal with 10-bit resolution can achieve a maximum read-out transmission rate around 115 kbps. The implanted sensing device was implemented with a double-layered rectangular PCB in 3x4.5 cm2 by surface mount device (SMD)-type discrete components with consuming power around 90 mW. The overall systemic efficiency can reach about 25 % within the coupling distance of 3.5 cm. We have successful designed, implemented and tested all the functional blocks of the bi-directional wireless implantable biomicrosystem. This implantable device is ready for implanted animals experiment for varied neuroscience studies.

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