Abstract
in order to realize solid-state components with higher power and efficiency, power-combining techniques (PCTs) must be used. The PCT can integrate large numbers of devices with minimal signal distribution and combining losses, while maintaining desired amplitude and phase relationships. Two techniques are used for power combining: Planar (Circuit-level) PCT where the power combined through the circuit-level (planar-level), and Spatial PCT where the power combined in space. The planar PCT is divided into : corporate-feed PCT and chain (serial) PCT. For Corporate PCT the paper presents photographs and characteristics of Q-band and Ka band MMIC amplifier chips that illustrate the sate-of-the-art of circuit-corporate PCT using MMIC technology. For Chain PCT the paper presents the circuit schematic and characteristics of 85-116-GHz four-stage InP HEMT MMIC Amplifier.
Spatial power combining provides enhanced RF efficiency by coupling the active components to large-diameter guided beams or waveguide modes, rather than the planar transmission lines used in circuit-combining structures. The paper presents Current State-Of-The-Art for MMIC and MEMS Spatial PCT.