Improvement of Rated Power and VSWR Characteristics for Termination Resistor with Integrated Matching Network and Efficient Thermal Management

Abstract

Matching RF and Microwave signals to components within a circuit has become more challenging for circuit designer as operating frequency and power handling requirement increase. Termination resistors with excellent power handling capability with superior voltage standing wave ratio (VSWR) characteristics are needed for microwave circuit components in various wireless and telecommunication application. In this work, we extensively studied to improve the power handling capability and VSWR of termination resistor while maintaining the smaller size. We optimized the energy transmission within the component and significantly improved the efficiency of energy transfer between the transmission lines and the terminations. We discussed techniques of improving power handling capability and reduction of thermal fatigue to the component’s structure. By using innovative techniques of heat transfer we appreciably increased power handling capability while keeping the product size as minimum. We constructed matching network using integrated microstrip line at the beginning of the resistor material. We optimized impedance matching by varying length, width and pattern of transmission line as well as using defective ground structure (DGS) technique. We minimized the detrimental influence of component footprint and resistor material characteristics effect on signal reflection. Considering the necessary microwave parameters and required thermal performance, we designed and manufactured Pb free high power termination resistor. Several sizes of resistor are manufactured with rated power of 20 Watt, and 100 Watt which provides excellent VSWR characteristics for frequency up to 4 GHz. Resistors are manufactured for 50 ohm impedance; however, methods mentioned in the study are applicable to any impedance.