Distributed active balun with improved linearity performance

A new active balun topology is introduced allowing to overcome gain and bandwidth limitations of traditional out-of-phase power dividers. Proposed architecture employs distributed circuits as Artificial Transmission Line Pair (ATLP) and Split Drain Distributed Amplifier (SDDA) for achieving a broadband signal balancing and featuring a positive insertion gain too. In this contribution a complete theoretical analysis for the ATLP and SDDA principle of operation is provided together with the description of the actual design flow. MMIC test vehicle operating on the multi-octave frequency range 2-18 GHz proves the effectiveness of presented topology.