US Patent 8666350 Analog front end circuit for cable and wireless systems

A circuit includes, an attenuator responsive to an input signal and a feedback signal, a variable gain low-noise amplifier responsive to the attenuator and to the feedback signal, a tracking filter, a frequency converter, and an RSSI responsive to the variable gain amplifier to generate an output signal to which the feedback signal is responsive. The frequency converter may be a mixer having a single-ended input and a differential output. The circuit may further include an analog baseband block responsive to the mixer to filter out high frequency signals. The tracking tuner performs bandpass filtering operation on the output signals of the variable gain low-noise amplifier.