- This topic has 10 replies, 4 voices, and was last updated 9 years, 3 months ago by alistu.
-
AuthorPosts
-
-
July 27, 2015 at 10:14 am #22751Tayyab MehmoodParticipant
Good-evening everyone,
I need to improve the EVM(%) value of 16-QAM 4-SCM based simple optical system with SMF of 5 Km without using DSP components at the receiver side, kindly suggest me the changes in the parameters as well as the other components to improve the EVM (%) value. -
July 28, 2015 at 9:58 am #22810Ashu vermaParticipant
Hello tayyab
Since EVM is generaly a deviation of point at receiver side from ideal one,you can analyze it by incresing power.i am not able to open your file,but reccomend you firt try to simulate the system without fiber of 5 km,see the evm directly at receiver side.if you get good evm then try the transmission by boosting the signsl using edfa .i think this will help ypu. -
July 28, 2015 at 10:54 am #22812Alessandro FestaParticipant
Hi Tayyab, have you tried to decrease the noise of the electrical amplifier? It seems too close to the signal level to me.
-
July 28, 2015 at 10:27 pm #22829alistuParticipant
Hi Tayyab,
Increasing the power using optical amplifiers such as EDFAs is a good way, but optical and electrical amplifiers have a noise figure in reality which might make further problems for you. I suggest that you also boost the launched power by increasing the laser power on transmitter side as well.
Cheers
-
July 29, 2015 at 12:02 am #22831Ashu vermaParticipant
Hi tayyab,alessandro give a good point, and consider the points of alisthu which are almost similar to my first reply.
-
July 29, 2015 at 5:17 am #22853Tayyab MehmoodParticipant
1. I simulate the whole system without going into the optical domain but I did not get the improved results.
2. I also sweep the input power, data rate, frequency spacing between each electrical carrier of 4-SCM, EDFA gain and the gain & noise power of electrical amplifiers at the transmitter side as well as at the receiver side but did not get the improved EVM value. I am still working on it..-
July 29, 2015 at 5:37 am #22854Alessandro FestaParticipant
Can you attach your file without the optical domain?
-
July 29, 2015 at 5:48 am #22855alistuParticipant
I ran the optisystem file you have attached and got wrong results. I think the priority in here is to correct the system, and then improve EVM if it was necessary. And it is not something one would be able to modify by changing the aforementioned parameters. I myself am currently reading more about SCM OFDM and will let you know if I find the problem with your simulation.
-
-
July 29, 2015 at 7:19 am #22863Tayyab MehmoodParticipant
Here is the File without optical domain
-
July 29, 2015 at 7:23 am #22865Tayyab MehmoodParticipant
Hi alistu, would you suggest me the corrections to do in the optical system.
-
July 31, 2015 at 4:11 am #22943alistuParticipant
Hi Tayyab,
I am sorry I might have made a mistake then. But may I ask why you haven’t used any BER test sets or a haven’t used any method to be able to calculate the BER of your system? In other words, how would you evaluate the performance of your system in terms of BER now? I suggest that you do so.
-
-
AuthorPosts
- You must be logged in to reply to this topic.