Reference Hardware


The current Reference Hardware Platform is comprised of:

GPSDO setup


The GPS reference needs to be configured before use and a Windows utility can be downloaded from the Leo Bodnar website.

The GPSDO should be configured with:

  • 10000000 Hz output frequency

  • 32mA output drive strength


A block diagram can be seen below.


The Mini GPS Reference is powered via USB and this can be cabled to a NUC USB port, along with the SDR.


The GPS reference is locked when its LED is constant and not flashing.

Minimal configuration

It is possible to have a configuration:

  1. Without a GPSDO

  2. Without a duplexer

However, this will impact performance.

Without a GPS locked external reference there may be sufficient frequency error to result in network instability.

Without a duplexer there would be two antennas, one connected to receive and another to transmit. Such use will result in reduced RF performance, as there will be no receive filtering, meaning that the base station transmit signal may cause receive interference, along with any other out-of-band signals. Meanwhile the transmit output will not be filtered.