Abstract
We present a W-band radiometer to detect the metal targets on the ground environment. The type of the designed radiometer is the total power radiometer(TPR) for the simple configuration. The front end of the TPR consists of only the Mixer and LO for miniaturizing the system. Because the radiometer system does not use the low noise amplifier, we use matching circuits and a diode detector configured as a voltage doubler to compensate the degradation of sensitivity. We solve the temperature variation problems by filtering the reference voltages of the radiometer output signals. Through some experiments, we have verified that the designed radiometer system has good performances in detecting metal targets lying at several hundred meters.