Measuring the Fried parameter $r_0$ (atmospheric optical coherence length) in optical link scenarios is crucial to estimate a receiver’s telescope performance or to dimension atmospheric mitigation techniques, such as in adaptive optics. The task of measuring $r_0$ is aggravated in mobile scenarios, when the receiver itself is prone to mechanical vibrations (e.g., when mounted on a moving platform) or when the receiver telescope has to track a fast-moving signal source, such as, in our case, a laser transmitter on board a satellite or aircraft. We have derived a method for estimating $r_0$ that avoids the influence of angle-of-arrival errors by only using short-term tilt-removed focal intensity speckle patterns.