Active Millimeterwave Antennas on Silicon

In this paper we design and optimize a planar patch antenna using the Transmission Line Matrix (TLM) method. The planar antenna is part of a monolithic integrated millimeter-wave emitter on a high resistivity silicon substrate and features a radiation frequency in the 60 GHz range. The active part will be realized by a negative impedance amplifier, here an IMPATT diode. The antenna patch operates not only as a radiating element but also as a resonator. For designing an appropriate patch resonator one important design criterion is the impedance match with the impedance of the IMPATT diode. This represents a very critical requirement due to the low negative resistance level of the IMPATT diode. Therefore a full wave analysis has to be applied to the whole structure including patch and feeding network. The TLM method has proven to be a very powerful and flexible numerical method for the analysis of various planar and three-dimensional topologies, especially useful for the investigation of broadband structures, but yet has not been utilized extensivly for the analysis of radiating structures. It will be shown, how TLM can be used for antenna modeling. The necessary steps for the design of the patch antenna will be demonstrated and results will be validated by comparison with those obtained by a spectral domain method.