[dvblast-devel] dvblast reception units

[Georgi Chorbadzhiyski]

On 01/22/2015 04:11 PM, Raúl Mansilla wrote:
> It´s about the units you use for measure reception levels of the locked
> satellite carrier. Where can I see how you calculate these number so I can
> put them into other measure units? I´m attaching you how we usually see them
> in a Tandberg Receiver...
> 
> <VALUE bit_error_rate="0"/>   -> normally this value is 1e-8...
> 
> <VALUE signal_strength="56283"/>   -> How can I measure it in dB´s?
> 
> <VALUE SNR="65535"/>    -> I think I can set them from 0 – 100% being
> 100%=65535  but it is also usually shown in dB´s

This values depend on your kernel driver. I don't know how to convert them
in every occasion.

dvblast just reports what it gets from the kernel.

Try this:

DVBLAST=$(dvblastctl -r $SOCKET fe_status)
STR=$(echo "$DVBLAST" | grep -i "strength" | cut -d\: -f2 | sed -e 's| ||g')
SNR=$(echo "$DVBLAST" | grep -i "snr" | cut -d\: -f2 | sed -e 's| ||g;s|\-||g')
[ "$STR" = "" ] && STR="0"
[ "$SNR" = "" ] && SNR="0"
STR=$(echo "scale=3;$STR/655.36"|bc)
SNR=$(echo "scale=3;$SNR/655.36"|bc)

if [ "$ADAPTER_TYPE" = "DVB-C" ]
then
  STR=$(echo "scale=3;$STR*100"|bc)
  SNR=$(echo "scale=3;$SNR*100"|bc)
fi

echo $STR $SNR