Eigen Value Analysis Santanu Das Calculate Eigen Vectors

Eigen Value Analysis Santanu Das

Calculate Eigen Vectors We should get only one eigen vector 1. 2. 3. 4. So take Each frequency bin and time bin Write the Visibility Matrix Calculate the Eigen Vectors. Plot the absolute values of the Eigen Vector.

Problem with the Autocorrelation 1. Auto-correlations are large due to the presence of noise. 2. We can’t use the auto-correlations directly. If we use then the Eigen values will be almost same as the autocorrelations. So I replaced the autocorrelations with the following expression As we know

1. 5 feeds 2. Same polarization Result with 2015 data Probably due to noise I am getting the signals in all the eigen values. So we can’t separate out the signal.

1. Total 10 feeds 2. Same polarization Increase the number of feeds That will probably decrease the effect of noise and we can separate the signal from a particular direction 1. We get all the signal in only one Eigen value. 2. The signal from the other Eigen values are much smaller. 3. We still have some signal left from the Sun. But its significantly small.

20 feed with both polarizations 1. We see three Eigen values. 2. 2 Eigen values are expected from the Sun 3. The third one is probably due to noise isolation? Not sure. 4. During night time there are two large eigen values. Why? 5. Its separating out the Sun signal very clearly.