RF Attenuator Performance Qualification

1. Verify Attenuation Meets Specification

Establish a test link using an RF signal generator and a power meter.
Compare signal power values before and after connecting the RF attenuator.
Calculate the deviation between the actual attenuation and the nominal value.
If deviation is within the allowable range, the attenuation is qualified.
Excessive deviation beyond the design threshold indicates a faulty attenuator that cannot effectively weaken the signal.

2. Assess Impedance Matching Status

Use a network analyzer to test the VSWR (Voltage Standing Wave Ratio) at input and output ports.
VSWR directly reflects the degree of impedance matching.
Good matching is close to ideal; a high VSWR indicates severe impedance mismatch.
Impedance mismatch increases signal reflection loss, reduces power transmission efficiency, and affects downstream equipment.
An excessive VSWR signifies a faulty attenuator.

3. Inspect Physical & Connection Integrity

Perform a thorough visual inspection of the RF attenuator.
Check the casing for damage, deformation, or oxidation.
Inspect interfaces for looseness, poor contact, bent pins, or damage.
A damaged casing can lead to internal component moisture ingress and failure.
Interface failures directly disrupt signal transmission. Presence of defects indicates a damaged attenuator.

4. Test Frequency Response Stability

A high-quality RF attenuator must maintain stable attenuation performance across its rated frequency range.
Use a network analyzer to test attenuation at multiple frequency points.
Small deviations across the specified range indicate stable frequency response.
Large fluctuations in attenuation with frequency change, exceeding allowable limits, indicate abnormal frequency characteristics.
Such an attenuator cannot function stably across its operating band and is considered performance-damaged.

Note: All tests should be conducted per the attenuator's datasheet and relevant industry standards (e.g., MIL-STD, IEC).

RF Attenuator Qualification Procedure | Core Performance Verification