Rugged 18 GHz Cable Assembly for High-Throughput Production Testing
For test applications that require precise, repeatable measurements, GORE® PHASEFLEX® Microwave/RF Test Assemblies have been designed to provide optimal phase and amplitude stability with flexure. The expanded polytetrafluoroethylene (ePTFE) material used in their construction enables them to be rugged yet lightweight and deliver reliable performance with longer service life and reduced equipment downtime. This results in lower costs for testing in laboratory, production and field test environments (see Figure 1).
Cable assemblies have a significant impact on the total cost of testing in production environments. Frequent troubleshooting, time-consuming recalibration and re-testing all have a direct impact on throughput in a manufacturing process which, in turn, significantly increases costs. Also, having to use a torque wrench to connect and disconnect each product from the test equipment slows the testing process.
Figure 1 GORE® PHASEFLEX® Microwave/RF Test Assemblies are designed for test applications that require precise, repeatable measurements (photo courtesy, Agilent Technologies Inc.).
In response to customer concerns about these issues, Gore has engineered a new Microwave/RF cable assembly that is smaller, more durable, lighter in weight and easier to use. Figure 2 shows the construction of the new GORE® PHASEFLEX® Microwave/RF Test Assemblies (18 GHz, 0G cable type) that are specifically engineered for high-throughput production test applications in the wireless infrastructure market. Although the assemblies' performance has been optimized for frequencies through 6 GHz (the "sweet spot" common to these types of high-throughput production test applications), they will perform well through 18 GHz, a well established performance category in the industry.
Figure 2 Construction of GORE® PHASEFLEX® Microwave/RF Test Assemblies.
The new GORE® PHASEFLEX® Microwave/RF Test Assemblies incorporate a unique connector design that includes a larger knurled area to facilitate hand-tightening as well as free-spinning, precision-coupling nuts that enable the connector to spin faster, returning to the home position in 1-1/2 turns while providing the necessary amount of engagement for a robust connection. The new cable assemblies maintain accurate measurement repeatability while withstanding demanding conditions such as continuous flexing, temperature cycling, broad temperature ranges and frequent connecting and disconnecting to the instrument or device under test (see Figure 3).
Figure 3 Typical amplitude stability with flexure and shake for 1 m (39.4 in) cable assembly.
What the new 18 GHz 0G type cable assemblies bring to the party is maximum strain relief at the point where the cable and connector meet and an internally ruggedized construction that is more durable, delivering crush resistance of 187 pounds per linear inch (85 kg/cm). These assemblies can withstand 100,000 flexures at a minimum bend radius of one inch. They are resistant to chemical exposure and can even be submerged in water. Available in 1.0 and 1.5 meter lengths with both SMA and N-type male connectors, they are also designed to be easy to use for operators in the wireless telecom market who may be inexperienced in handling cable assemblies. They are smaller and more lightweight, and can be connected and disconnected manually – the ergonomic design includes an enlarged knurled area that makes hand tightening easy and eliminates the need to use a torque wrench to accurately connect and disconnect, increasing throughput on the manufacturing line. Table 1 summarizes the specifications of the new 18 GHz 0G type cable assemblies.
The new 18 GHz cable assemblies reduce overall testing costs because they last longer, decreasing the frequency of cable assembly replacements. One reason is that Gore manufactures every component used in them, from the dielectric and the helically wrapped outer conductor to the ePTFE jacketing. This enhanced performance stability ensures ultra-precise measurements and accurate repeatability, reducing the risk of testing errors and the need for time-consuming troubleshooting and system calibration.
W.L. Gore & Associates, Inc.