頁籤選單縮合
| 題 名 | A Programmable Gain Amplifier for Automated Gain Control in Auditory Prostheses |
|---|---|
| 作 者 | Hintea, Sorin; Paul Faragó,; Roman, Marius N.; Oltean,Gabriel; Feştilă, Lelia; | 書刊名 | Journal of Medical and Biological Engineering |
| 卷 期 | 31:3 2011.06[民100.06] |
| 頁 次 | 頁185-192 |
| 分類號 | 410.01344、410.01344 |
| 關鍵詞 | Cochlear implants; Continuous interleaved sampling; Programmability; Automated gain control; |
| 語 文 | 英文(English) |
| 英文摘要 | A cochlear implant (CI), also called a bionic ear or electronic cochlea, is an implantable electronic device that can partially restore hearing to profoundly deaf patients by directly stimulating the patient’s auditory nerve via surgically implanted electrode arrays. Hearing impairment of the severely deaf patients translates into a 70-80 dB hearing loss, reaching a hearing dynamic range as low as 15-25 dB. As such, gain control systems are needed in CIs to map the acoustic input signal into the patient’s hearing dynamic range. This paper proposes a programmable gain amplifier (PGA) which can be used to implement a dual-loop automated gain control (AGC). An analog signal processing technique is used, due to its advantages over the digital processing equivalents, such as potentially lower power consumption and higher processing speed. Programming the analog processing parameters, i.e. gain levels and time constants, is done by means of digital control words that set the values of corresponding bias currents. Computation of the control words is done in a digital fashion, allowing a hardware description language implementation of the gain control algorithm. This adds flexibility to the resulting gain control system: ability to choose between a feed-forward and feed-back topology, ability to choose between different compression functions: linear, logarithmic and power-law, and ability to set the desired compression limits. Finally, a fully adaptive gain control system is implemented. The programmable aspect of the adaptive AGC implementation also enables the adjustment of the AGC operation to meet the patient’s individual needs. Circuit simulation proves the functionality of the proposed PGA for automated gain control in CI applications. |
本系統中英文摘要資訊取自各篇刊載內容。