Re: MMDVM & UDRC

Annaliese McDermond
 

On Dec 7, 2018, at 12:14 AM, Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io> wrote:

Hi Annaliese

There are a set of filter coefficients for 48 kHz sample rate in a branch of the MMDVM firmware. I’ll look into slotting those in and altering the other variables.

Ideally I’d recalculate them in MATLAB as floating point but my license for it ran out. Octave can probably do it though. Even rescaling from Q15 format will probably give enough precision.
If you have some matlab code, I have a Matlab 2015b license on my Mac that I could spit out the coefficients for you. I’m mildly familiar with the process because I’ve done it for filter coefficients in the OpenHPSDR FPGA code that I was playing with.


It’s bizarre seeing Linux kernel AX25 being mentioned. I wrote that stuff 23 years ago and last looked at it 20 years ago. I’m not sure I could add anything to that discussion these days.

Jonathan G4KLX
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Annaliese McDermond (NH6Z)
nh6z@...

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