How to combine Random Gaussian Noises from different sources

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I have generated two different white gaussian random noises in MATLAB using two different seeds. For example:

Asn1 = sqrt(noisepow1/2)* (randn(size(As))+1i*(randn(size(As))));

Asn2 = sqrt(noisepow2/2)* (randn(size(As))+1i*(randn(size(As))));

Here, noisepow1 and noisepow2 are amplitudes of noise powers, As is signal array.

I will need to add these two noises to calculate the SNR. As the two noises are from different sources, I am confused about how to add these two noise signals.

I can't simply just add Asn1 and Asn2 to calculate the total noise, because some signal samples will have opposite phases. Should I add like below:

AA = sqrt(noisepow1/2).*(randn(size(As)));

BB = sqrt(noisepow2/2).*(randn(size(As)));

Asn = AA+BB + 1i*(AA+BB);

I am confused about the addition operation of these two white Gaussian random noise signals. Any suggestion would be helpful. Thanks.