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I'm building a Sat-View that draws a small bar-chart for available satellites and their signal strength (or better: their signal-to-noise-ratio / SNR).

The javadoc doesn't say what value-range to expect for the SNR. The NMEA-Standard says 0-99, but even in best conditions my G1 doesn't reach that value. I also read that different manufacturers use different value-ranges for the SNR, so is that true for android-devices, too? Or is there a unified value range on that plattform and if so, what is it?

The lack of information in the docs leads me to suspect I just get the "raw" SNR from the driver, in which case I'd like to know: What do you think is the best approach to visualize that unknown value-range in a bar-chart?

A: 

Have you found your answer? I am facing the same question and google brought me to this page. After a bit research, I found a SNR->signal strength tab in this article. http://gauss.gge.unb.ca/papers.pdf/SNR.memo.pdf

SNR is mapped to signal strength [0,1,4-9] COMMENT
SNR: >500 >100 >50 >10 >5 >0 bad n/a COMMENT
sig: 9    8    7   6   5  4  1   0   COMMENT

Maybe we can visualise signal strength instead. Is that reasonable?

Dan