[Discuss-gnuradio] Noise Source Output ~3dB Higher on E310?

[John Malsbury]

This was a surprising one.  When set with a the same seed (regardless of value) and amplitude, the noise source (gaussian) seems to have 3 dB higher power when running on E310 vs. an i7 platform.

(GNU Radio commit 8220b79653c6c7999a18fed075bdb1c41bca0613 on i7)

(e3xx release 3 from here: http://files.ettus.com/e3xx_images/e3xx-release-3/)

This problem came up when running unit tests on modems that check BER vs. Eb/n0.

Has anyone come across this before? 

I'm sure there's a good reason/explanation for this - but I'm too tired to think of it. 

-John

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