Cables and connectors help route signals through a system but at best add nothing to the signals. In extreme cases, faulty cables and connectors can lead to signal losses and system failures. For that reason, a trend is for cables and connectors with low loss and high reliability at higher frequencies.

Cables and cable/connector assemblies are available in a variety of types, including those that keep their shape once machined, (semirigid cables), those that are flexible, and hand-formable cables, which provide a combination of flexibility and rigidity. All of these cable types are available in a variety of diameters, with smaller diameters supporting higher operating frequencies.

For example, Mini-Circuits now offers handformable ("Hand-Flex") cable assemblies for applications from DC to 18 GHz as well as armored cables with Type N connectors for use through 18 GHz. The Hand-Flex cable assemblies are available in standard lengths from 3 to 24 in., with only 0.85 dB insertion loss for a 10-in. assembly with SMA male connectors at either end.

Huber + Suhner manufactures flexible cables, form-stable cables, and hand-formable cable assemblies through 40 GHz. For example, the company's SUCOFORM cable assemblies are hand formable with 5.4 dB loss through 40 GHz.

Crystek Corporation recently introduced its 190 series CCK26.5 and CCSMA26.5 flexible cables (Fig. 1) with K (2.92-mm) and SMA connectors, respectively, for applications from DC to 26.5 GHz. The cable assemblies exhibit attenuation of 0.50 dB/ft. at 26.5 GHz and shielding effectiveness (SE) of better than 90 dB.

SYNFLEX cables from Synergy Microwave Corp. feature low loss. The firm's SF series cables are usable from DC to 18 GHz while the SFR series are suitable for applications from DC to 8 GHz.

Micro-Coax has developed UTiFLEX MCJ185A flexible cable for space applications. With low loss (0.5 dB/ft.) through 32.3 GHz, the cables are formed of low outgassing, radiation-resistant materials that can handle operating temperatures from -200 to +150C.

To assist specifiers with sorting through cable and connector choices, W. L. Gore & Associates recently announced a white paper (Fig. 2). Additional cable assembly suppliers include Flexco Microwave, Maury Microwave Corp. (), MegaPhase, RF DepotRFMW Ltd., Rosenberger of North America LLC, Spectrum Elektrotechnik GmbH, Times Microwave Systems, and VMR Electronics.