Tactical Targeting Network Technology System as a new generation of tactical data link system of American troops, on the basis of the “full-duplex communication” realizes the statistic priority-based multiple access protocol(SPMA) in the link layer. The link layer protocol or MAC protocol of tactical data link describes rules that the nodes access wireless channel. Using appropriate MAC protocol, can more reasonably allocate the limited wireless bandwidth resources, is the key technology of tactical data link. This paper mainly study the channel occupancy state of SPMA protocol, from two aspects of the physical layer and network layer to statistical channel occupancy state, then adopts prediction technology effectively to estimate the actual channel state. Designing an accurate hybrid channel load statistical method, which effectively reduce the channel conflict, ensure real-time of data and transmission probability of high priority data.