base amplitude modulation circuit

Base amplitude modulation is suitable for small signal amplitude modulation, and its circuit is as shown in the figure.
  In the figure, B, G, and C are high-frequency bypass capacitors. Tl and T2 are high-frequency transformers, the LC circuit resonates at the carrier frequency, and the passband
is 2Fr. .
Switch, and then detect it through a low-pass filter . This detection method is called diode square rate detection. Since the amplitude of the input high-frequency signal is small, it
is called a small signal square rate detector.