Circuit level paralleling of devices using two-way DC block for efficient power combining

Abstract

This paper presents a novel means for paralleling transistors at circuit level for combining power using a Microstrip coupled line based "two-way DC block". This approach offers several features in a single elegant structure, such as: power division, impedance matching between an arbitrary source and loads, inherent DC blocking capability and convenient post-production tuning where necessary. The implemented amplifier achieves the above mentioned functionalities with 17.5 dB of gain in 200 MHz bandwidth and 30dBm of output power at 50% output drain efficiency at Ku band.