Subject: Re: [Roll] question on gain control

From: Yoav Ben-Yehezkel <[email-masked]>
Date: Sun, 25 Jul 2010 23:40:47 +0300

One clarification –

Selection processes are with the transmission gain margin (lower
transmission power).

Maintenance processes are without the margin (higher and possibly maximal
transmission power).

So, after selection there’s margin reliability on the link for the
maintenance processes.

Thanks,

Yoav

*From:* Yoav Ben-Yehezkel [mailto:[email-masked]]
*Sent:* Sunday, July 25, 2010 11:37 PM
*To:* [email-masked]'
*Subject:* question on gain control

Hi,

I would like to probe the WG’s opinion on the issue of transmission at
different transmission gains to obtain more reliability on the link quality.

For example, somehow indicating the transmission power level on DIS/DIO/DAO
(maybe by percent of or db less than maximum transmission level) to make
sure that metrics are calculated/parents are selected, etc. only based on
transmissions received with low transmission gains.

We’ve used this to make our topologies more stable in proprietary solutions.
The motivation is to have sufficient level of margin for noise before
messages at high gain will not be received properly (i.e. if messages are
received at 6dB less than the maximum transmission gain, there’s room for at
least 6 dB more noise before the messages will not be received – 6 dB is a
lot of margin, so topologies remain very stable with this kind of margin).

I believe that such an option used by the RPL would bring benefit, and maybe
belong to one of the RPL drafts (i.e. metric, OF, other?).

Would this something the RPL WG would consider to add?

Your inputs would be greatly appreciated.

Regards,

Yoav