Global quasi-optical receiver simulation with FDTD

Low-cost millimeter-wave integrated-circuit receivers can be realized by the advancement in lithography and micro-machining technology. To design and optimize this type of receiver, it is essential to consider the close proximity among the antenna, passive devices and active devices. The FDTD method is used to analyse a quasi-optical receiver at millimetre wavelength to provide better design and hence optimum mixer operation. The receiver can be divided into two interconnecting analytical domains. The primary domain is two-dimensional and involves the analysis of the lens alone. The secondary analysis involves the planar antenna with its passive and active devices. The receiver considered is a 90 GHz integrated double-slot lens antenna with a Schottky diode. The voltage and current spectrum across the diode and across the load can provide vital information about the mixer operation. The mixer conversion loss defined as the IF power in the 50 ohm load divided by the RF power available at the diode terminals can be calculated for different input power levels.