Power and gain considerations in distributed amplifiers based on composite right/lefthanded transmission lines

Composite right/left-handed (CRLH) unit cells can be used to develop new distributed circuits with novel functionalities. In particular, their use in distributed amplifiers leads to an improvement in their power performance. An analysis of the intrinsic power performance of distributed amplifiers based on CRLH unit cells is presented in this contribution. As a result, optimum values for the unit cell phase shifts in different amplifier configurations are determined. A three-stage pHEMT CRLH unit cell-based distributed amplifier has been built and measured. The experimental results validate the main conclusions derived from the simplified analysis and suggest that a dual-fed configuration might provide an optimum output power with significant gain values.