Early Development of the Project Sanguine Radiating System

The Project Sanguine system is the result of many years of research and analysis into radiating system configurations. The paper describes the early portions of this search, the recognition of equivalences among several of the candidate systems, the conduct of an early transmission experiment, and the initial efforts at system optimization and choice of the radiating system configuration. The early research and tests provided confirmation of the theory that a vertically polarized -field propagates through the earth ionosphere cavity at ELF with a slight forward tilt which allows it to enter the sea water and then penetrate to considerable depths. It also verified the behavior of the earth return antenna element through the operation of an experimental system. In addition, a system optimization program was developed to allow the cost of achieving various levels of system performance to be assessed.