Hi Harald,
Thanks for looking at my log!
So somehow your MS is moving extremely fast away from
the cell,
In actuality the MS was stationary during the entire test, and the
fixed distance between the BTS and the MS was the distance between two
rooms in one apartment turned lab - a few meters.
reporting enormous timing offset and causing a high TA
to be used on the TCH.
And despite that high TA, the MS still reports a timing offset of 63.
I suspect some serious problem in the TA control loop either on MS or BTS
side.
The two MS in this test were Motorola C139 for the origin leg of the
call and Pirelli DP-L10 for the destination leg. Both phones were
running their respective manufacturers' original fw, i.e., no
FreeCalypso fw in this test - hence FC is not to blame here. With
both MS being of the standard historical type-approved variety,
incorrect logic in the MS can probably be ruled out - so the finger of
suspicion points at nanoBTS then?
Aside from the generally unfortunate situation that the combo of
OsmoCNI+nanoBTS is not officially supported by anyone, there is also
the fact that this particular nanoBTS unit came from ebay in completely
unknown condition - a defect can't be ruled out... I have another
nanoBTS unit that is also from ebay but from a much more reputable
seller, and that one is probably defect-free - but that nanoBTS is for
GSM850 band, and I don't feel safe transmitting in that band without a
license - looking at my SA, that GSM850 band is much more crowded than
PCS1900 around here.
M~