首页>
外国专利>
Demodulator employing cyclic switching of the gain factor of an operational amplifier between different predetermined values
Demodulator employing cyclic switching of the gain factor of an operational amplifier between different predetermined values
展开▼
机译:在不同预定值之间采用运算放大器增益因子的循环切换的解调器
展开▼
页面导航
摘要
著录项
相似文献
摘要
An AM demodulator circuit arrangement includes an operational amplifier having at least two alternate input networks and at least two alternate feedback networks which can be selectively activated by switching signals so as to establish an amplifier gain factor having at least two different predetermined values. The switching signals are derived from a square wave clock control signal of a frequency which is an integral multiple of the carrier frequency of the AM input signal supplied to the demodulator. As a result of the periodic variation of the amplifier gain factor, the demodulated signal is produced at the output of the amplifier. Such a demodulator avoids offsets or interference frequencies due to manufacturing tolerances. Sensitivity to interference at higher harmonics of the carrier frequency can be suppressed by appropriate selection of the waveform of the gain factor variation, which is determined by the waveform of the switching signal.
展开▼