EHF active integrated arrays designed for device integration

A conventional transmit system design comprises a high gain antenna followed by a solid state power amplifier (SSPA). However, the SSPA used within a transmit system have in general multiple devices to provide the high output power and suffers from the combining losses within the unit. To reduce these losses, low to medium power amplifiers are integrated within an array architecture. Spatial power combining is employed thus the path loss from the amplifier to radiating element within the array is the only source of combining loss. It is therefore preferred to locate amplifiers as close as possible to the radiating elements. This is essential when developing array architectures at EHF where a microstrip feed network is utilized. The resistive losses increase rapidly with frequency hence the path loss from amplifier to radiating element could be severe. In addition, the structural aspects of the array must be such to accommodate device integration near the radiating elements.