ip.access nano 3.5G : Any advice on how to configure channel and power?

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Harald Welte laforge at gnumonks.org
Wed Aug 9 17:23:34 UTC 2017


Hi Alan,

I think unless you've moved to the US, the 850+1900 MHz bands should not
have any macro network carriers.  However, there are of course possibly
other users in that spectrum that create a high interference level for your
signal.

If you have a spectrum analyzer around, you can check the signal levels
and check which UARFCN might me most suitable.  Make sure to cover both
the uplink and the downlink part of the UARFCN.

Aside from interference, it could also be that there is simply insufficient
output power configured.  There are a number of related DMI MIB entries,
I don't recall the details right now, but the following values appear to
be related to RF power

cpichTxPowerLowerLimit (2594) = -100
cpichTxPowerUpperLimit (2595) = 500
eAgchPowerOffset (3494) = -20
eDpcchToDpcchPowerOffset (3492) = 4
eHichErgchPowerOffset (3495) = -64
cpichTxPower_001 (2531) = -99999
hsScchPowerOffset (2875) = -10
maximumPowerCapability (1863) = 130
maximumTotalWidebandTransmitPower (2593) = 0
minimumPowerCapability (2044) = 0
powerHeadroom (2567) = 8
primaryCpichPowerPercent_002 (3606) = 100
maximumAllowedUlTxPowerDch (2216) = 24
dlPowerControlPerRab_001 (3486) = ({SRB_AND_DL_RAB_TYPE_3_4_SRB (1), -30, -20}, {SRB_AND_DL_RAB_TYPE_13_6_SRB (2), -30, -20}, {SRB_AND_DL_RAB_TYPE_CS_AMR_12_2 (3), 50, -20}, {SRB_AND_DL_RAB_TYPE_CS_UNKNOWN_DL64 (4), 0, -27}, {SRB_AND_DL_RAB_TYPE_PS_IB_DL64 (5), -30, -20}, {SRB_AND_DL_RAB_TYPE_PS_IB_DL128 (6), 0, -20}, {SRB_AND_DL_RAB_TYPE_PS_IB_DL384 (7), 40, -20}, {SRB_AND_DL_RAB_TYPE_PS_IB_DL32 (8), -40, -13})
ulPowerCtrlPerRab_001 (3487) = ({SRB_AND_UL_RAB_TYPE_3_4_SRB (1), -20, 1, 2, 1, 1, 30, 80, 0, 4, 2}, {SRB_AND_UL_RAB_TYPE_13_6_SRB (2), -20, 1, 2, 1, 1, 30, 80, 0, 4, 2}, {SRB_AND_UL_RAB_TYPE_CS_AMR_12_2 (3), -27, 1, 3, 0, 1, 40, 80, 30, 6, 1}, {SRB_AND_UL_RAB_TYPE_CS_UNKNOWN_UL64 (4), -27, 1, 6, 0, -1, 70, 90, 50, 4, 2}, {SRB_AND_UL_RAB_TYPE_PS_IB_UL64 (5), -20, 1, 6, 1, 1, 70, 90, 10, 4, 2}, {SRB_AND_UL_RAB_TYPE_PS_IB_UL128 (6), -20, 1, 6, 1, 1, 60, 80, 0, 4, 2}, {SRB_AND_UL_RAB_TYPE_PS_IB_UL384 (7), -20, 1, 6, 1, 1, 100, 120, 100, 4, 2}, {SRB_AND_UL_RAB_TYPE_PS_IB_ULHS (8), -10, 1, 10, 0, 1, 40, 150, 30, 2, 1}, {SRB_AND_UL_RAB_TYPE_PS_IB_UL32 (9), -20, 1, 6, 1, 1, 50, 50, 0, 4, 2})
powerOffsetPpm (3602) = 2
rfMeanWidebandPower (1784) = 0.000000
aichPowerOffset (1264) = -5
bchPowerOffset (1295) = -20
fachPowerOffset (1342) = 20
pchPowerOffset (1482) = 20
pichPowerOffset (1491) = -5
primarySchPowerOffset (1502) = -50
sccpchTfciBitsPowerOffset (1603) = 12
secondarySchPowerOffset (1606) = -50

However, I guess it really only makes sense to start to play with those
values when attached to a transmitter tester that can actually observe
how the channel power changes.  If anyone has played with this so far,
now would be a good time to step forward :)

Another possible source of confusion could be that the phones have some
kind of logic that they don't scan on US frequency bands in case they
see macro cells on non-US bands.  This is pure hypothesis at this point.

-- 
- Harald Welte <laforge at gnumonks.org>           http://laforge.gnumonks.org/
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