Hi John,

It is my understanding that other protocols (like CDMA, UMTS, HSPA, LTE) have similar unencrypted, broadcast or "beacon" traffic that could be viewed the same way ...

correct.

But there are no tools like airprobe for CDMA or 3G or LTE ... why is that ?

I'm not sure if that's correct. At lest for LTE you should find several open source implementatiosn that at least claim to be able to decode the beacon/broadcast channel.

Is there a technical reason that they are much more difficult, or has it just not been done yet out of lack of interest ?

Yes, it is more difficult, as the modulation and encoding schemes are more complex. But the fundamental reason is probably that somebody needs to sit down and get it done. It's not like there is a magical group of people that just implements all of this for everyone else to use.

I'm not aware of a CDMA (IS-95 / CDMA2000) or WCDMA beacon receiver. But you you can find similar projects for TETRA, GMR and OP25 all under the Osmocom umbrella.

What's needed is somebody who scratches his (strong enough) itch for understanding / implementing the related bits of synchronization, demodulation and decoding.

Regards, Harald