题目/Title：A Fast-Settling Wideband-IF ASK Baseband Circuit for a Wireless Endoscope Capsule

作者/Author：
                        Baoyong Chi,Jinke Yao,Patrick Chiang,Zhihua Wang

期刊/Journal：IEEE Transactions on Circuits and Systems II-Express Briefs

年份/Issue Date：2009Apr.

卷（期）及页码/Volume（No.）&pages：Vol.56, No.4, pp. 275 - 279

摘要/Abstract：
A novel automatic-gain-control (AGC) architecture utilizing wideband current feedback is proposed for the baseband circuit of a wireless endoscope capsule. The baseband circuit consists of a fast-settling wideband AGC loop and an amplitude-shift-keying demodulator. Additional integrators in the reverse signal path provide negative feedback, bandpass-filtering effect, attenuating low-frequency noises, and dc offset from the radio-frequency front end. The baseband circuit fabricated in a 180-nm complementary metal-oxide-semiconductor process achieves a wide-intermediate-frequency (IF) carrier frequency in the range of 0.5-40 MHz, a measured settling time of 2 mus, and an input sensitivity of -57 dBm. The entire baseband demodulator dissipates only 5 mA, with a 1.8-V supply at a data rate of 1.37 Mb/s and an IF carrier frequency of 10 MHz.