I've been doing a good bit of satellite work and had the need to blow the dust off of a discontinued gr-gpredict-doppler OOT module and enhance it. The goal was to have a state value to pass in and key off of gpredict's perspective of if the satellite was visible or not for recording purposes (better yet preventing huge blind-saving files), and to better pass the doppler frequency through to GNURadio. So I've forked it (https://github.com/ghostop14/gr-gpredict-doppler.git
) and added a bunch of new features:
- Now adds freq output block to make it compatible with other message blocks like the USRP source
- Now supports AOS / LOS commands from gpredict - a state output message block compatible with all of the state inputs in the gr-filerepeater block is also produced. Result: A file record can be triggered to start when a satellite is in range, then automatically closed when it goes out of range.
- Enhanced the gqrx / gpredict radio control command handling to handle additional messages and correctly handle exit
[new] rotor block:
- Accepts inputs from rotctl / gpredict's rotor control.
- Az/El are passed in, interpreted, and packed in an output message with 'az' and 'el' meta keys
- A basic minimum elevation is added to the block where if the elevation is > min, an optional state output is produced (1= >= min, 0 is below min). Again this can be used with the gr-filerepeater adv sink
[new] az el limit block:
- Allows az/el min/max values to be set. If the rotor block output az_el is fed into this block, an output state message is produced for "inside the az/el limits" / outside the az/el limits. Again, this can interface with the file blocks
) has also gotten a lot of enhancements to help with controlling unsupervised file writes. The concept of this state 1/0 has worked its way through for easy file write control. The file sink can also now extract/save message-based data in exactly the same way streaming data was handled.
Anyway let me know if there's any other enhancement requests or if you run into any new issues.