OnSense is a hybrid spectrum sensing scanner using a combination of SDR and conventional receivers.
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OnSense is a hacktastic hybrid spectrum sensing scanner using a combination of SDR and conventional receivers. It is currently a simple wrapper for osmocom_spectrum_sense and is known to function with the HackRF Jawbreaker and UHD devices (but other devices supported by the osmosdr front end should work to some degree) and uses hamlib's rigctl (optionally via rigctld) to tune a communications receiver.

I've mostly been using OnSense with a HackRF Jawbreaker and an AOR-8600mk2 receiver. With a HackRF, OnSense is capable of scanning the entire military UHF band in less than a second and commands the AOR receiver to tune to the strongest detected signal. There is a mechanism lurking in the code that pretends to be an algorithm which tries to avoid attention deficit disorder in the receiver. It can only be improved upon.

The file "onsense.py" contains the application script. The "onsense" file is a simple bash script taking one of two alternate options, "civair" or "milair" and expects a HackRF device to be present. The "onsense_usrp" file is a bash script with options for a UHD device (tested with a B100/WBX combo). These bash scripts contain configuration options for onsense.py that I've used here with success. You may need to edit some or most of the options yourself, for some reason or another, mostly likely to try and avoid osmocom_spectrum_sense crashing so often, which OnSense conventiently handles fairly well (if osmocom_spectrum_sense seems to be crashier than usual simply disconnecting and reconnecting the HackRF device works for me).

More words will follow imminently, and probably more code. I'm trying to get my head around QT in order to give this a GUI and more features. A database is likely to put in an appearance in the near future too.

Oh yeah. I almost forgot. There's a hardcoded blacklist in "onsense.py". You either want to delete it or modify it, or both. Also, try and avoid receiving a mess of intermod. It will result in frustration and probably a headache.

Onsense spits out a bunch of characters as well as detection reports and perhaps desktop notifications as it eats output from osmocom_spectrum_sense. The characters emmitted on stdout are probably:

'c' ... a detection report was for a dwell centre frequency, and was surpressed by the mechanism for reducing detections of the 0Hz centre from each dwell. The -c option controls the margin used for centre suppression. This isn't needed for uhd devices as we use advanced tuning, although you should make sure the lo_offset is greater than half the sampling rate.

'x' ... a blacklisted frequency was supressed. The blacklist is currently hardcoded in "onsense.py"

'-' ... the power threshold for slave receiver tuning was reduced as some weaker signals may deserve attention

'=' ... the power threshold for slave receiver tuning is the squelch threshold

'.' ... no reports were received in a 1 second interval.

I use rigctld to control the conventional receiver. I keep grig running at the same time so I don't have to stare at the receiver to figure out what is going on.

Happy listening :)