In previous years, mmWave frequencies were used for niche military, aerospace, SATCOM and scientific research. This has changed, however, as emerging 5G, 60 GHz Wi-Fi, automotive radar and high speed data applications, operating in the tens to hundreds of GHz, are becoming common. The diversity of applications and the demand for higher frequency test systems are driving coaxial cable assemblies to the next level. These performance parameters for test cables extend beyond laboratory performance to address features specific to the new applications. From extremely tight tolerance for pristine laboratory conditions to rugged reliability for automated test facilities, the next generation of precision coaxial test cables operating at mmWave faces a wide range of "stiff" performance requirements. [ABSTRACT FROM AUTHOR]