It’s similar, in that both processes use impact to improve the soils.  However, RIC uses a relatively light weight (7 tons) falling a very small distance (3 to 4 feet), so its effect is very limited.  Its manufacturer suggests a maximum depth of compaction of 3 meters in very clean sands, decreasing rapidly with increasing fines content.  Dynamic compaction, on the other hand, uses weights of 6 to 20 tons falling from heights of up to 80 feet, and can achieve a significantly greater depth and degree of improvement.