GNU Radio Projects

This page provides an overview of the various projects and experiments I am or have been doing with GNU Radio and the Universal Software Radio Peripheral (USRP). GNU Radio is a free, open source software development toolkit that provides the signal processing runtime and processing blocks to implement software defined radio. The USRP provides a … Read more

Portable S-band Ground Station Update

I made good progress with the portable S-band ground station this week.

I took the receiver to the OZ7SAT lab to measure its performance. Using the USRP+DBSRX and no LNA we could easily detect a -132 dBm CW signal with modest FFT integration (fraction of a second) in a GNU Radio spectrum scope. Using the LNA we could go down to about -138 dBm, i.e. an improvement in SNR of 6 dB. These figures were measured at an SNR ~5 dB. This is excellent, but please note that this is not real “sensitivity” in the traditional sense because we were not demodulating or decoding the signal. We were simply integrating the spectrum for a fraction of a second to detect the presence of the signal. The measurements were done by sampling a 250 kHz wide spectrum.

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New vLog: Introducing the S-band Ground Station Project for LRO/LCROSS Reception

In this new video blog I am introducing a new project that has kept me occupied for a few weeks now: A low cost S-band ground station for receiving signals from NASA’s lunar spacecrafts LRO and LCROSS. More info at Receiving LRO and LCROSS. Based on the Universal Software Radio Peripheral (USRP) with DBSRX daughterboard, … Read more