居家或是醫院的心臟健康照護一直都是熱門議題。心臟病變是健康管理和監控的主軸，心臟發生問題若無法即時發現，常會造成醫療嚴重負擔，而不舒適的心電監控，使得病人不願意主動使用設備，常造成不可收拾的後果，以致於增加醫療負擔。一般的ECG量測方式，通常使用三個電極，兩個電極用於電生理訊號讀取，第三個電極為參考電極用於參考電位接地，其中參考電極通常接在右腳。由於供應三個電極的放大器的地線要連接在一起，造成電線需佈滿全身而非常不方便。
為了解決這種不便，本研究提出了兩種方法。第一種方法是使用公用電極而非右腿參考電極的兩電極ECG測量方法。供應這兩組電極對的放大器的電源及地線不用連接在一起，彼此獨立。同時，這兩電極以人體當參考電位透過皮膚進行連接，以完成ECG的量測。兩個電極在讀取電生理訊號後，分別經由兩個隔離放大器傳送到儀表放大器、濾波器、放大器，來產生ECG波形。隔離放大器之前的兩個電極放大電路分別用不同電源且地線不相接，隔離放大器之後的電路也用不同電源，其地線不相接於其他兩個電源的地線。然而，即便是新型的兩電極對心電圖可以極大地改善佩戴舒適度，也必須克服無線電位差的問題，才能無線化。方法二介紹了兩個具有兩個調幅頻率的類比收發機，並結合了兩個前端放大器，兩個電極對和一個差動放大器，以實現兩電極對無線心電波形。
經過實驗結果，方法一可得到肢體導聯I、肢體導聯II和肢體導聯III的ECG信號波形，其中以肢體導聯I最接近常規參考電極的心電圖波形。方法二的實驗結果表明，無線電位差成為可能，即可以在無線傳輸之後構成心電波形。兩電極對無線心電圖可以大大改善佩戴或測量的舒適度，而無需在身體周圍纏上太多導線。即使肢體導聯I仍清晰可見且具有可接受的信噪比，並且肢體導聯II和III 只有清晰的QRS綜合波被檢測到，依然在健康應用中穿戴舒適。
用此方法設計出可攜帶式的新型心電圖，去除佈線的干擾，提供了心電圖量測的方便性，同時也可發展無佈線的無線心電圖。舒適的佩戴方式，身體周圍沒有任何電線，大大提高了人們將其用於家庭，運動甚至醫院的醫療保健的之意願。

Aspects of health care for patients with heart disease in home or hospital settings are crucial topics of research. In particular, health management and monitoring of patients is critical. If not diagnosed immediately, heart disease can result in serious health problems, which may lead to a high burden on the health care system. Without comfortable electrocardiogram (ECG) monitoring systems, patients may not be willing to use the equipment, which can increase health care burden. An electrocardiogram (ECG) records the electrical activity of the heart using two electrodes to detect electrophysiological signals from the organ and one reference electrode (typically attached to the right leg) as the reference potential. An inconvenience of the three electrodes is that the grounds of the amplifiers are interconnected all over the body.
To address this inconvenience, this study proposes two methods. The first method is a two-electrode ECG measurement method with common electrodes instead of the reference electrode of the right leg. The power supply and the ground of the amplifier supplying the two electrode pairs are not connected and independent. Pasted on the skin with the body as the reference potential, both electrodes detect electrophysiological signals, transmitting the signals through two isolation amplifiers to an instrumentation amplifier (IA) filter and generating ECG waveforms. Both previous-stage electrode amplifier circuits of the isolation amplifiers used their respective power supplies; their grounds were unconnected to those of the power supplies. Similarly, the next-stage electrode amplifiers used their respective power supplies, with their grounds unconnected to those of the power supplies. However, even the novel two-electrode-pair ECG can highly improve the wearing comfort, it must become wireless by overcoming wireless difference problem. The second method introduces two analog transceivers of two amplitude modulation (AM) frequencies combined with two front-end amplifiers, two electrode-pairs, and one difference amplifier to implement two-electrode-pair wireless ECG.
In a first method, experiments yielded ECG signal waveforms in Leads I to III, with that of Lead I most resembling the waveforms of conventional reference electrodes. The second method experimental results demonstrate that the wireless difference is made possible, i.e., ECG can be constructed after wireless transmission. Two-electrode-pair wireless ECG can greatly improve wearing or measurement comfort without many wires around the body, even Lead I is clear with the acceptable signal-to-noise ratio and only clear QRS complex waves of Lead II and III are detectable for wearing comfort in the health applications.
These methods can be used to develop wireless ECG devices and portable ECG devices that eliminate the need for wiring to facilitate ECG measurement. The comfortable wearing without any wire around the body greatly enhances the people’s willingness to use it for health care at home, sports, and even hospitals.

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