Publications

Spatial power combining of many MMIC amplifiers at millimeter wave frequencies using a fixed array of microstrip antenna elements places unique demands on dielectric media. The substrate must be relatively thick to allow space for MMIC placement, must provide rather high thermal conductivity to disipate MMIC heat, and be of...

We describe the design and measurement of a hybrid-circuit, tile-approach subarray for use in spatial power-combined transmitters. The subarray consists of 16 monolithic millimeter-wave integrated circuit (MMIC) amplifiers, each feeding a circularly polarized cavity-backed microstrip antenna. The average performance across the 43.5-45.5 GHz band is as follows: EIRP 18.3 dBW...

Three designs for a 4-by-4 are described for use in a spatial power-combined transmitter. The subarrays are constructed using a hybrid-circuit, tile-approach architecture and are composed of 16 cavity-backed, proximity-coupled microstrip antennas, each fed by a 0.5 watt amplifier. Both linearly and circularly polarized subarrays have been constructed for operation...

The radiation efficiency of conventional microstrip antennas generally decreases when the substrate thickness or permittivity is increased because of loss to surface waves. However, constructing a metal cavity around the microstrip antenna prevents the surface wave propagation. Thus, the cavity backed microstrip antenna has been predicted to have increased radiation...