I don't understand clearly your question, but the damping ratio and natural frequency can be found mathematically as follows:
It is known that an ideal second order transfer function is as follows:
K*Wn^2
------------------------
s^2 + 2*zeta*Wn*s + Wn^2
If we extract the coefficients of both transfer functions' denominator and solve for zeta and Wn,
2*zeta*wn=3
Wn^2=2;
From this, Wn is found as sqrt(2) and zeta(damping ratio) is found as 3/(2*sqrt(2)). This means zeta is greater than 1, which is normal since both poles are real, which will result in an overdamped step response. Hope this helps.
