[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] TETRA phase adjustment bits

From: Harald Welte
Subject: Re: [Discuss-gnuradio] TETRA phase adjustment bits
Date: Mon, 3 Jan 2011 18:34:34 +0100
User-agent: Mutt/1.5.20 (2009-06-14)

Dear Tom (and others),

On Mon, Jan 03, 2011 at 11:22:11AM -0500, Tom Rondeau wrote:
> >
> > So the phase adjustment bits need to be set to the negated sum of the
> > phase shift of two other bits in the burst.
> >
> > Let's assume I'm using hc1, hc2 and thus look at the symbols 8 (bit 15+16) 
> > and
> > 108 (bit 215+216).

A friend has meanwhile (privately) solved the problem: It is not the sum of the
phase shift of two symbols, but the sum of the phase shift of all symbols in
the range n1...n2.  And as that range is always an odd number, we can always
compensate the cumulative phase shift in a single additional symbol.

> Have you looked at this paper?
> http://wsl.stanford.edu/~ee359/doppler2.pdf

I had seen this before, but thanks anyway.

I'll follow-up to this group once I'm getting anywhere with my code.

- Harald Welte <address@hidden>           http://laforge.gnumonks.org/
"Privacy in residential applications is a desirable marketing option."
                                                  (ETSI EN 300 175-7 Ch. A6)

reply via email to

[Prev in Thread] Current Thread [Next in Thread]