W-Band Sb-Diode Detector MMICs for Passive Millimeter Wave Imaging

A W-band monolithic microwave integrated circuit (MMIC), including an Sb-heterostructure diode on a GaAs substrate, has been demonstrated. The MMIC also includes the RF choke and output shorting capacitor essential to detector circuits. Additional input matching has yielded peak sensitivities on the order of 10 000 V/W and equivalent bandwidths of 40 GHz. Using these circuits in conjunction with current W-band low-noise amplifier technology can achieve the sub-1degK noise equivalent temperature difference necessary for producing discernible images with W-band passive imaging cameras.