Fatigue Life Analysis and Maintenance of High-power Coaxial Cable Assemblies

Long-line high-power coaxial cable assemblies are mainly used in systems with long distances between transmitters and antennas. Their laying environments and high-power usage environments frequently make them to be in the state of thermal expansions and contractions. Because the inner conductor is restrained, it will withstand significant internal stress of cross section. Due to the integrity of the inner conductor and its low binding force, the internal stress will accumulate in the position where the inner conductor strength is relatively weak, causing fatigue effects to occur first and ultimately leading to failure, which affects the use of the system. In this paper the failure of long-line high-power coaxial cable assemblies after long-term operation is analyzed, and theoretical analysis and software simulation are conducted on the service life of long-line high-power coaxial cable assemblies. The ultimate number of internal stress impacts that the conductor inside the cable assemblies can withstand from cracking to failure has been verified through experiments. Life evaluations of high-power coaxial cable assemblies of different lengths under different loading powers and suggestions of maintenance during the life cycle are provided.