在目前，記錄老鼠的神經細胞訊號都需要在大腦電極上連接電線至擷取系統。即使使用無線類比傳輸來代替有線系統，一些問題例如較大雜訊干擾、電路的困難度仍會影響實驗的狀況。假如能去除電線及類比無線傳輸，許多有趣的實驗將可能實行，且實驗的設計將因此簡單化。為了能免除電線的連接，及提昇無線傳輸的品質，我們發展了一個以藍芽為架構的無線傳輸資料擷取系統，能很輕易地讓老鼠背負其上。這個系統由3個部分組成：(1)一個兩級放大器放大ECG與EEG，放大倍率由150至10000；(2)數位電路，用來取樣、處理數位波形；(3)藍芽無線傳輸模組，以RS232為主控傳輸介面。數位資料(9kHz取樣頻率，12位元解析度)被傳送到藍芽模組，且再利用藍芽傳輸無線傳送到附近的電腦端。最多有4個頻道可同時在5公尺範圍內持續地傳送某段時間。老鼠背包尺寸大小為長4.5公分，寬4公分，高3公分，重40克，並且由鎳鎘充電電池供電可達30至60分鐘。這套系統可成功地在清醒的、長期植入下的老鼠身上測量其生理訊號。在未來系統改進方面，將採用以USB為主控傳輸介面的藍芽模組，來提昇傳輸速率達到藍芽理想的傳輸速度700kbps。

　　Recording neural cells signal from animals currently requires a cable to connect brain electrodes to the data acquisition system. Although wireless analogue transmission sysems have been applied to replace the wired system, some problems like easily induced interference and difficulties to implement still disturb the animal experimental conditions. To eliminate the need for a cable and improve the wireless transmission quality, this aims of this study is to develop a Bluetooth_based telemetry data acquisition system for recording the physiological signals of rats. The system is composed of a 2_stage preamplifier with gain from 150 to 10000 for EEG and ECG sensing, a digital circuitry for sampling and processing the digitized waveforms, and Bluetooth wireless transmission module with RS232 host interface. Digitized data (up to 12bits of resolution at 9kHz sampling rate) are transferred to the Bluetooth module and sent wirelessly to nearby computer by Bluetooth wireless transmission. Up to 4 channels can be transmitted simultaneously for sustained periods at a range of 5 m. The entire Bluetooth acquisition module can be mounted at a rat’s backpack which measures 4 cm╳4.5 cm╳3 cm, weighs 40g, and is powered from rechargeable Ni-Cd battery with a lifespan of 30-60 min. The device was successfully used to record signals from awake, chronically implanted rat. In a future improvement, Bluetooth module with USB host interface would be used to increase transmission data rate ideally up to 700 kbps of Bluetooth transmission rate.

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