- This topic has 10 replies, 3 voices, and was last updated 10 years, 1 month ago by boldoo.
-
AuthorPosts
-
-
November 6, 2014 at 6:37 am #14989boldooParticipant
Dear all,
how to draw clear 2ASK ?
-
November 6, 2014 at 11:55 am #15023Damian MarekParticipant
Couldn’t you use a simple externally modulated laser for ASK? I don’t believe you need a coherent type setup. If not could you attach an article or explanation of 2ASK?
Thanks
-
November 6, 2014 at 6:21 pm #15024RavilParticipant
I agree with Damian, regular 2ASK format doesn’t require coherent detection (can’t open your scheme for some reason…)
-
November 6, 2014 at 10:23 pm #15061boldooParticipant
Hi
need change Receiver? then how to see 2ASK constellation map?
But if it is succeeded, I will add phase modulation, fiber and QAM receiver. My final aim is square-16QAM constellation.
-
November 7, 2014 at 10:06 am #15078Damian MarekParticipant
Wouldn’t a simple NRZ signal be considered 2ASK? If so I think the constellation diagram would be as simple as the one attached. The signal varies between two values 1 and 0 and the phase is always the same.
-
-
November 7, 2014 at 11:46 am #15083RavilParticipant
NRZ and RZ format just defines the bit interval duration and in my opinion 2 of them can be used for 2ASK.
-
November 7, 2014 at 11:48 am #15084RavilParticipant
The presented constellation diagram belongs to ASK, I think. For 2ASK we should have 2 different values of amplitudes on axis if I’m not mistaken…
-
November 10, 2014 at 8:59 am #15133Damian MarekParticipant
Ok, but then that would be exactly the same as BPSK, which is not necessarily a bad thing. Boldoo let us know what constellation diagram you want. If it is what Ravil suggested then you could simply use a 2-QAM or BPSK modulator.
-
-
November 11, 2014 at 4:39 am #15181boldooParticipant
Dears, since I need to draw 16QAM constellation, I asked about 2ASK. then I drew attached fig.
is it 16QAM right? there is any requirement?
-
November 11, 2014 at 2:26 pm #15209Damian MarekParticipant
Hi Boldoo,
That looks exactly like 16-QAM glad we could help. In this case you could have used our QAM components to create the constellation diagram, but nevertheless it indeed looks correct.
Cheers!
-
-
November 13, 2014 at 9:45 am #15336boldooParticipant
thanks Damian,
now that 16QAM pass through fibers, constellation is rotated as certain phase. but i can’t fix this to correct phase. You can see another post of mine.
-
-
AuthorPosts
- You must be logged in to reply to this topic.