Blog Post: GPS Tuning the Librem 5 Hardware

Phone Hardware debugging in a duopoly

Society is getting pretty used to the idea that the data and applications on phones are completely controlled by large corporations.

Purism is working hard to change that with the Librem 5.

Because of the market capitalization and duopoly control of the phone OS vendors, the hardware tool vendors use are trapped into one of those two OSes (Android or iOS).

GPS debugging as a case example

We’ve been working on antenna tuning in the Librem 5 for awhile to get the best possible reception. The GPS antennas are especially important because their signal level is so close to the noise floor.

The available GPS antenna tuning procedure is a GPS simulator, but the simulator requires feedback from the phone OS to help tune the antenna. If you are on Android the simulator vendor provides an apk that converts the NMEA to a format that the tools can use to do the tuning.

So now we have a tool to do the tuning but no way to use it.

Read more here:


Interesting little conundrum and solution. I’d be interested to hear some time in the future - when nothing else more pressing is on the radar - about testing and signals and antennas. The RayZone-1800 must have given all kinds of lessons on what works and what doesn’t and where to compromise. A possibility to understand L5 (its “ability envelope”) much more in depth than almost any other phone.

I feel your pain.

I resisted the joke yesterday, but here it is:

You can’t just tap it against a table and hold it to your ear?