# Notation for a Probability Distribution

I came across this in a paper:

$$w_i\tilde{} \mathcal{CN}(0,2\sigma_{w_i}^2)$$

I am wondering what it refers to.

In English: $w_i$ is drawn from a complex normal distribution with mean $0$ and variance $2\sigma_{w_i}^2$.

This is the complex normal distribution. The real and complex values of the distribution are both normally distributed.