Discussion @ 1704. Demodulation @ Timus Online Judge

Hints Fyodor Menshikov 21 Apr 2009 21:30

1. Minimize sum of squares of differences, not sum of absolute values of differences.

2. It is important, that constant AMP (amplitude) is the same for all bits.

3. There is no test with negative amplitude.

Re: Hints svr 28 Oct 2009 17:35

Hint should be:
notion of appropriate statistical processing:
extracting a and b in a+b*k from noise
Or
MNK
Or
sequental analysis
Or
maching learning
Or
optimal decision theory
What artical in Wikpedia should read?

Re: Hints Pavel Atnashev 10 Nov 2009 12:39

Start with this one:
http://en.wikipedia.org/wiki/Frequency-shift_keying

Re: Hints Alipov Vyacheslav [Tomsk PU] 22 Jul 2010 01:48

Would you be so kind to give the slightly more detailed description of your solution?
I tried to used DFT but it seems to be too sensitive to noise.

I heard of Arctan-Differentiated Demodulator, but I can't find the literature on this theme. Does anybody know, is it applicable here?

Re: Hints Vedernikoff Sergey (HSE: АОП) 23 Jul 2010 02:29

Use OLS (ordinary least squares) estimator for this problem

Re: Hints Alipov Vyacheslav [Tomsk PU] 23 Jul 2010 19:55

Thanks a lot. I've never used this method before. But it's worth keeping in mind :)

Discussion of Problem 1704. Demodulation