S-Parameter - Insertion & Return Loss by means of TDR Measurement

S-Parameter ⇒ Insertion & Return Loss

Measuring the S-parameters of printed circuit boards, connectors and cables is enormously important ensuring high signal integrity. Selected S-parameters are very often also called insertion loss (S₂₁=IL) and return loss (S₁₁=RL).

TDR ⇔ S-Parameter (Time Domain ⇔ Frequency Domain)

Since the TDR signals can be converted to frequency domain data via the Fourier transform, the complex S-parameters can be calculated from the time domain data. Our TDR devices are calibrated for this purpose using OSLT (Open, Short, Load, Thru) measurements, just as is done in classical vector network analysis.

Performing Measurements

The S-parameter measurements can be performed using the Seunis software. This user interface provides an easy-to-use wizard for performing the OSLT calibration.

In the adjacent figure a single-ended S₁₁ measurement is shown in dB format (magnitude) as well as in a Smith chart. Phase and VSWR display are available as additional formats.

Required Accessories for Return Loss Measurements (RL)

• Time domain reflectometer DTDR-65 (single-ended & diff.) or STDR-65 (single-ended)
• Time domain reflectometer DTDR-800 (<1GHz, single-ended & diff.)
• Seunis basic software
• Software module DS₁₁ (diff.) and/or S₁₁ (single-ended)
• Phase matched SMA cabel SPMC-P (diff.) or SCC-P (single-ended)
• OSL calibration kit (S03K30R-OSL3 or SCKE-SF-R)

Accessories for Insertion Loss Measurements
(single-ended IL)

• Time domain reflectometer DTDR-65
• Seunis basic software
• Software module F2P (full 2-port)
• Phase matched SMA cable SPMC-P or 2×SCC-P (single-ended)
• OSLT calibration kit (S03K30R-OSLT)