A terrestrial-digital multimedia broadcasting (T-DMB) and digital audio
broadcasting (DAB) low intermediate frequency (IF) receiver comprises a
low noise amplifier (LNA), an image rejection down-conversion mixer, a
low pass filter, an amplifier, a local oscillator, a phase-locked loop,
and an automatic gain controller (AGC). Particularly, the LNA, the image
rejection down-conversion mixer, the low pass filter, the amplifier, the
AGC, the local oscillator, and the phase-locked loop are integrated in
monolithic semiconductor integrated circuit substrate. The AGC supplies a
gain control signal to the LNA and the amplifier according to the
magnitude of the RF signal, and the gain control signal is controlled by
a null control signal based on a null signal comprised in a received
radio frequency (RF) signal.