S-Parameter Export

The NanoVNA-H can export measurement data in standard Touchstone format (.s1p and .s2p files) for use in simulation software, documentation, and data analysis.

Touchstone Format Overview

Touchstone files are industry-standard formats for S-parameter data:

Format	Contents	Use Case
.s1p	S11 only	One-port measurements (antenna, load)
.s2p	S11 and S21	Two-port measurements (filter, amplifier)

Save S-Parameter File

1. Complete your measurement and verify data quality
2. Tap the screen to open the menu
3. Navigate to SD CARD
4. Tap SAVE S1P or SAVE S2P
5. The file is saved with an auto-generated filename

Note

Filenames are automatically generated based on date/time or sequential numbering (e.g., DATA0001.S1P).

File Format Details

S1P Format (One-Port)

! NanoVNA-H Touchstone Export
# Hz S RI R 50
50000 0.123456 0.654321
100000 0.234567 0.543210
...

Header line meanings:

• # Hz - Frequency in Hertz
• S - S-parameter data
• RI - Real/Imaginary format
• R 50 - Reference impedance 50 ohms

S2P Format (Two-Port)

! NanoVNA-H Touchstone Export
# Hz S RI R 50
50000 0.123 0.456 0.789 0.012 0.345 0.678 0.901 0.234
100000 0.234 0.567 0.890 0.123 0.456 0.789 0.012 0.345
...

Each line contains: frequency, S11_re, S11_im, S21_re, S21_im, S12_re, S12_im, S22_re, S22_im

Tip

The NanoVNA-H can only measure S11 and S21. S12 and S22 are set to zero in the S2P file. For reciprocal networks (like passive filters), S21 = S12.

Shell Commands

Export via serial console (requires PC software to save):

# Get measurement data
data 0    # S11 data (real imag pairs)
data 1    # S21 data (real imag pairs)

# Get frequency list
frequencies

The data is output as space-separated real/imaginary pairs, one point per line.

Using Exported Files

In Simulation Software

Import .s1p/.s2p files into:

• Keysight ADS
• AWR Microwave Office
• QUCS
• LTSpice (with Touchstone support)
• HFSS
• Sonnet

In Python

import skrf as rf

# Load S1P file
network = rf.Network('DATA0001.S1P')
print(network)

# Plot S11
network.plot_s_db()

In MATLAB

S = sparameters('DATA0001.S2P');
rfplot(S)

Practical Examples

Document Antenna Performance

1. Connect antenna to CH0
2. Calibrate and sweep
3. Save as S1P file
4. Import to simulation or documentation

Characterize a Filter

1. Connect filter between CH0 and CH1
2. Perform full 2-port calibration
3. Save as S2P file
4. Use in circuit simulation

Create Reference Data

1. Measure known component
2. Save S-parameter file
3. Use as reference in future comparisons

Data Quality Tips

Tip

Before exporting:

• Ensure valid calibration
• Check for reasonable data (no spikes or noise)
• Use adequate sweep points for your application
• Set appropriate frequency range

SD Card Requirements

• FAT32 formatted SD card
• Adequate free space (each file is typically a few KB)
• Insert card before powering on for best reliability

File Management

Files are saved in the root directory of the SD card:

/DATA0001.S1P
/DATA0002.S2P
/CAPTURE001.BMP
...

Caution

There is a limit on the number of files in the root directory (varies by SD card). Periodically transfer files to a computer and delete from the card.

Retrieving Files

Options for accessing saved files:

1. Remove SD card: Insert in computer’s card reader
2. SD card menu: Browse files on the NanoVNA-H display
3. Shell commands: Use sd_list and sd_read commands

# List files on SD card
sd_list

# List only S-parameter files
sd_list *.S?P