How can I evaluate the arg min/argmin of a secuence in Simulink/real-time?

I am wondering whether someone could give me some hints on how to evaluate/implement the math function arg min/argmin in Simulink.

Let's say that I have the following expression, I am reading it as, the minimum value of x that makes (x) smaller than zero

where (x) is a scaled version of 16 autocorrelation from x

My question is how can I implement that in Simulink?

Thanks in advance,

Regards