Complex sentence: Based on the success of these early experiments, the Department of Defense proposed to deploy a network of OTH-B radars as an early warning system, to detect incoming enemy bombers and cruise missiles.
Split into simpler sentences: Based on the success of these early experiments, the Department of Defense proposed to deploy a fully-operational radar system. The operational system consisted of multiple OTH-B radars functioning as an early warning system, to detect incoming enemy bombers and cruise missiles.