Use with OpenBTS on Amateur Bands

[AndrewHeim]

Occasionally projects intersect in interesting ways - this could be one.

There is an interest among the amateur radio community around getting a cellular base station set up and operating on amateur radio bands. There appears to be some overlap around TDD Band 40 (more details here: https://www.reddit.com/r/amateurradio/comments/9cfhqg/cellular_phone_on_ham_bands/).

There is also an open source cell base station software: OpenBTS (http://openbts.org/, and repo here: https://github.com/RangeNetworks/openbts). So the pieces exist. And here is a nifty demo: https://www.youtube.com/watch?v=pTb1_v8M6iA

It looks like the ZeroPhone uses a GSM modem. I tried digging up spec sheets, but was unable to find a clear answer to whether it can be made to work on Band 40.

Can it work on Band 40? And is there any interest in combining a hacker phone with a hacker base station?

[CRImier]

I'm interested in making ZP accessible for amateur radio tinkering - I'd like for ZeroPhone to be a platform for all kinds of ideas =) I've also addressed the mentioned thread on Reddit yesterday. TL;DR the GSM modem is physically capable of, what, 850, 900, 1800 and 1900 MHz? If we're talking about LTE bands, it's not going to be achievable until we, at least, have an LTE modem working on whichever band is being discussed. For example, our current pick for the 4G modem is SIM7500E, and it says "FDD-LTE B1/B3/B7/B8/B20", which, if interpreted as "bands it will support", doesn't list B40 - but maybe one of the other modems listed in the issue does?

As for hacker base station - it sounds something like the mentioned Reddit thread was talking about - if that's the idea, I like it! It doesn't sound like something that would have to be ZeroPhone-specific (as in, the idea ought to work with any phone), but it can be enhanced by whatever ZeroPhone can offer in terms of hackability - for even better integration! So, there definitely is interest - I can take the hackability into account when designing PCBs and working with software, for a start, then see if I have some more time to spare to help whoever decides to work on AR goals more closely =)