The recent interest in coherently detected MIMO-OFDM systems has fueled research efforts on various channel estimation methods. Few, however, have addressed the practical problem of estimating the instantaneous channel length. This necessary but often overlooked component of channel estimation is crucial to accurate channel estimates in many OFDM channel estimation techniques. In this paper we propose a method for jointly estimating the channel and instantaneous channel length. We describe the algorithm in detail, provide a mathematical framework, and show simulated results, both in terms of the estimation accuracy and the impact it has on a system's packet error rate (PER) performance.