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.

 
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