應用於物聯網具 145uW 315MHz 倍頻技術之射頻發射機

Abstract

本論文主要針對透過利用室內光源激發的無線傳輸技術，設計與開發創新光激發無線射頻標籤(Photodiodes RF Tag)系統，此系統不需要額外的電力、也不需要電池裝置，回收且再利用室內光源的能量來供給無線感測器系統。此項技術，解決了過去微型化無線感測器系統的能量供給問題，並且實現低功耗、低成本、高速率資料傳輸的無線傳輸系統。此晶片採用 0.18um 1P6M CMOS 標準製程進行製作。近年來無線通訊快速的進步，微波與毫米波通訊系統已廣泛的使用在行動通訊、光通訊及區域網路相關的應用上。為了使無線收發端得到低相位雜訊、低成本信號源與低消耗功率的純淨訊號源，注入式鎖態振盪器漸漸地被實際使用。在論文中所開發的光激發無線射頻標籤系統，透過光源的激發，進行能量以及資訊的傳輸。為了獲得低相位雜訊，在設計上採用多相位注入鎖定式振盪器結構。此架構可以降低製程變異的影響或減少振盪頻率造成的偏移。此外，再透過一個鎖相迴路來進行頻率鎖定以及校正，此迴路僅需在無線資料發送時進行鎖定，在感測器工作時，則可以關閉，來節省能源消耗。為了降低整體的功率消耗，我們在晶片中設計了穩壓電路提供穩定的 0.8V 電壓源來供給整個系統。此發射機的發射功率為-21.324dBm ，發射頻率為 315MHz ，數據傳輸率約2Mbps，其系統總功率消耗為145uW。整體晶片面積為0.49mmx0.93mm。

This paper presents an innovative RF Tag system powered by an indoor light source. The RF transmitter design includes a trans-impedance amplifier, a sub-harmonically injection locked phase locked loops (PLL), and a low-power Class-E power amplifier. The prototype chip was fabricated in a 0.18m CMOS process. Nowadays, with rapid development in wireless communication, short-range communication systems have been widely used in wireless sensor networks and Internet of Thing (IoT) applications. Different from typical RF communication, the proposed system relies on recycling indoor light sources as an energy source. The new technology solves the problem of shortage of energy supply in miniaturized wireless sensors, however, it requires low-power and high data-rate wireless communication system that can be supported by the constrained energy harvested from the indoor lights. A wireless transmitter is usually the most power consuming blocks in the active wireless tags. The chip was fabricated using 0.18 um CMOS technology and was verified first on an assembled PCB. The proposed wireless transmitter achieves a maximum transmit power of -21.3dBm and data rate of 2Mbps while total power consumption is 145W. The chip area including pads is 0.944mm 2 . The measured results match well the theoretic analysis and the simulation results.