Combined gain-enhanced power recycling feedbacks for distributed amplifier-based CRLH-leaky wave antennas

A distributed amplifier based CRLH-leaky wave antenna (LWA) equipped simultaneously with two types of power recycling scheme is proposed. By connecting a closed loop to the LWA on the drain side of the distributed amplifier, we can obtain gain enhancement compared to the one directly terminated without the loop. In addition to this, by using a rat- race coupler connected to the gate line, we can have extra +3dB gain increase theoretically. The operation frequency is designed at the broadside frequency of the CRLH-LWA. The methodology is demonstrated through the measurement and simulation in this paper.