Insertion Loss Magnitude and Phase Stability Testing (<40 GHz)
Introduction:
This document describes how insertion loss (S21) magnitude and phase stability is performed on two fixtures; the first
being a wrap of the cable around a 4.5 inch diameter mandrel and the second being a plus to minus 180 degree bend
test around two mandrels perpendicular to the plane of the cable assembly.
Method 2:
1.
2.
3.
4.
5.
The VNA is calibrated using 2.4 mm standards and adapters with appropriate calibration constants kit as
needed.
The cable assembly is connected to the VNA.
A mandrel with a 2.25” radius is placed adjacent to one side of the assembly.
The S21 parameter is stored in memory for the upcoming test condition.
The cable is disconnected, coiled 360 degrees around the assembly and reconnected this position. The cable
should be allowed to follow its natural coil. Do not twist or toque the cable assembly. At least one full sweep of
the signal generator is allowed to occur. See Figure 1.
Figure 1.
6. The change in the magnitude and phase of insertion loss (S21) is recorded through 40 GHz at 5 GHz intervals.
This is done using the data divide by memory function.
7. The cable is then returned to its normal and relaxed position. Once again S21 is stored in memory for the
upcoming test condition.
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Do not Reproduce or Distribute.
Method 1: In accordance with IEC 60966-1 section 8.6.2 (method 1)
8. The test fixture for bend testing is placed adjacent to the assembly. The cable assembly is clamped at the ends
and wrapped around the upper mandrel and brought to a 180 degree bend with respect to the initial plan of the
cable assembly. See Figure 2.
Figure 2.
9. The change in the magnitude and phase of insertion loss (S21) is recorded through 40 GHz at 5 GHz intervals.
10. The cable assembly is wrapped around the lower mandrel and brought to a negative 180 degree bend with
respect to the initial plan of the cable assembly. See Figure 3.
11. The change in the magnitude and phase of insertion loss (S21) is recorded through 40 GHz at 5 GHz intervals.
Figure 3.
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Do not Reproduce or Distribute.
12. The cable assembly is brought back to its relaxed state. See Figure 4.
13. The change in the magnitude and phase of insertion loss (S21) is recorded through 40 GHz at 5 GHz intervals.
Figure 4.
Information is Swift Bridge Technologies Confidential & Proprietary
Do not Reproduce or Distribute.