應用於物聯網技術上之低成本鎖相放大器研究

Abstract

物聯網時代的來臨，預告了新一代產品將具備無線傳輸資料、即時監控環境資訊的功能，也等同於宣告了世界即將踏入智慧生活的新世代。為了能維持搜集資料的精準性與完整性，如何在感測器端與無線傳輸端降低雜訊的干擾便顯得相當重要；另一方面，用來將感測器資訊上傳至網際網路的無線網路技術，也需要克服環境雜訊可能造成的影響，未來才能針對特定區域的特定目標進行即時資訊監控。 本論文為一低成本鎖相放大器研究，傳統的鎖相放大器大多由弦波作為輸入訊號，但是在電路複雜度方面，方波電路的製造成本比弦波電路來的低。因此，本研究將探討商用IC組成的鎖相放大器電路在驅動波形為方波與弦波下抑制雜訊的能力，分析當鎖相放大器全面採用方波數位化後，數位鎖相放大器在抑制雜訊方面可能遭遇的影響。在未來的物聯網產品中，廠商可以在製造成本與產品精準度的取捨中，挑選適合的鎖相放大器設計。

With the maturation of IoT technology, the new products are necessarily equipped with the abilities that can deliver wireless data and monitor real-time environmental circumstance, and it also declares that the world is going to enter the new era of intelligent living. In order to maintain the precision and integrity of the collected data, the ability of reducing noise interferences in both sensor part and wireless transmission part becomes the main point when deciding the efficiency of IoT products. Additionally, the wireless internet technology, which is responsible for uploading the data collected by sensor, has to conquer the impact of environmental noises. Under these premises, we are able to perform real-time monitoring toward the target within the certain area. In this master’s thesis, we examine the impact in the ability to against the interference when we change the sine wave into square waveform in the input part of low cost lock-in amplifier, hoping that we can lower the cost of lock-in amplifier by replacing the highly complicated sine wave with the simpler square waveform. This will help companies to lower their cost if they can choose the lock-in amplifier with appropriate data precision that matches their product.