xaVNA T/R and two port
The xaVNA is a two port VNA with a typical frequency range of 137MHz to 3.5GHz (accuracy specs guaranteed to 2.5GHz). It plugs directly into USB and requires no additional power supply. All measurements are done using an intuitive and easy to use UI on a computer.
It is both open source hardware and open source software, with a GitHub repository containing all schematics, PCB layouts, FPGA VHDL, and software:
What is a VNA useful for?
A VNA (Vector Network Analyzer) allows you to measure the impedance of an arbitrary device (such as an antenna) across a wide range of frequencies, as well as the transmission coefficient (gain/loss and phase) of a two port device (such as an amplifier, filter, or isolator).
It can do everything an antenna analyzer can do, but 10x better: it gives you phase information as well, and lets you see the exact complex impedance of an antenna, allowing you to easily design matching networks without tedious trial and error tuning.
- Frequency range (guaranteed specs): 140MHz to 2.5GHz
- Frequency range (typical): 137MHz to 3.5GHz
- Signal level: -20dBm to 10dBm
- S11 trace noise: << 0.1dB
- S11 dynamic range (calibrated): > 50dB
- S21 dynamic range:
- 70dB, f < 800MHz
- 50dB, f >= 800MHz
- Dimensions of the VNA board: 10cm x 10cm
- Weight: <200g (xaVNA T/R)
- Weight: <400g (xaVNA two port)
- Interface: Micro USB
- RF ports: SMA Female
- Current draw: ~500mA @ 5V
- Windows, Linux, and Mac OS will be supported
xaVNA two port
The xaVNA two port is composed of 2 xaVNA T/R boards synchronized to the same clock, and has two TX/RX capable ports. This allows full S parameter characterization of the DUT, and enables the use of more advanced calibration techniques like unknown thru, as well as being able to correct for more error sources such as imperfect port matching.
Accuracy comparison (measured vs simulated)