mariuszprus
Newbie level 6
I am proposing my PhD thesis in Optical Network.
I'm looking for a problem to solve in a PON network.
1. E.g I read recently about DBA algorithms in PON networks. This is very interesting topics for my, but i don't know is there any problem not solved at this area. I was looking for some information in IEEE but i can't found any interesting issue.
2. I found some information about near-far problem in PON network. If I good know this problem was solved by burst mode tranciver in OLT.
OLT needs to know signal strength to set decision threshold
If large distance between near/far ONUs, then very different attenuations
If radically different received signal strength can't use a single threshold
– EPON: measure received power of ONU at beginning of burst
– GPON: OLT feedback to ONUs to properly set transmit power
I've heard that this solution is good only at speeds of 2.5 G. In speeds 10G we have more mistakes in network. Mayby this is a good PHD topics ? Solve this issue in a different way. Can anyone confirm that such a problem that occurs in the networks at speeds higher than 10G?
What is caused by the near-far problem?
-bad receivers? Can we compare this problem to the behavior of the human eye? (When looking at the sun and then go into the dark room we can't see anything? but when we leave the dark room to clearly, we can see exactly)?
-electronic systems that are unable to quickly process the signal?
I don't have good devices for research. I must based only on the simulation result e.g in OPNET Modeler.
Regards
any help I would appreciate
I'm looking for a problem to solve in a PON network.
1. E.g I read recently about DBA algorithms in PON networks. This is very interesting topics for my, but i don't know is there any problem not solved at this area. I was looking for some information in IEEE but i can't found any interesting issue.
2. I found some information about near-far problem in PON network. If I good know this problem was solved by burst mode tranciver in OLT.
OLT needs to know signal strength to set decision threshold
If large distance between near/far ONUs, then very different attenuations
If radically different received signal strength can't use a single threshold
– EPON: measure received power of ONU at beginning of burst
– GPON: OLT feedback to ONUs to properly set transmit power
I've heard that this solution is good only at speeds of 2.5 G. In speeds 10G we have more mistakes in network. Mayby this is a good PHD topics ? Solve this issue in a different way. Can anyone confirm that such a problem that occurs in the networks at speeds higher than 10G?
What is caused by the near-far problem?
-bad receivers? Can we compare this problem to the behavior of the human eye? (When looking at the sun and then go into the dark room we can't see anything? but when we leave the dark room to clearly, we can see exactly)?
-electronic systems that are unable to quickly process the signal?
I don't have good devices for research. I must based only on the simulation result e.g in OPNET Modeler.
Regards
any help I would appreciate