Radial Power Combiners—An Overview: A Comprehensive Analysis of Power Combiners, Their Structures and Evolution From Their Inception to the Present

The demand for progressively higher microwave power levels is growing fast. In the past, traveling-wave tubes (TWTs) played a key role in constructing a wide range of microwave systems for various applications, such as radars, satellites, and wireless communication links. However, their poor resilience to degradation significantly affects system reliability. Meanwhile, TWT amplifiers (TWTAs) are expensive, bulky, and require a considerable warm-up time and high-dc voltage levels, especially in low-frequency bands
[1]
,
[2]
.