Setting TX Power for Cell Modem using qmilcil

[Harald Welte]

On Thu, Oct 26, 2017 at 05:15:57PM -0500, Balaji Sivakumar wrote:
> Is there a NAS command to set the Tx power for Cell Modem? Or logically is
> it possible to set the tx power for cell modem?

This would be highly unusual and have implications in terms of spec compliance
as well as possibly regulatory compliance.

In 3GPP cellular networks, the transmit power of the MS/UE is always under
control of the base station.  This is due to the fact that only the network
operator can determine which is a safe transmit power level avoiding any
unneccessary interference with surrounding cells on the same frequency (in 2G + 4G).

In 3G, it's actually worse due to its CDMA nature. A single phone transmitting
at too high power can have significant impact on the noise floor for all other
uplink transmissions by other phones at the same time.

So if Qualcomm had exposed the capability to manually adjust the transmit power
on the QMI side in an easy way, I would be seriously surprised.

You can use your own base station (such as OsmoBTS as Open Source) or a
handset tester to instruct the phone/modem for a given transmit power, if needed
for some lab / testing purpose.

Regards,
	Harald

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