Evaluation of an FM/CW Range Measurement System for VTOL Landing

A Precision Ku-Band FM/CW Range Measurement System was designed and built by Cubic for the Naval Ocean Systems Center to test and evaluate its effectiveness as a landing/guidance system for VTOL aircraft. Primary equipment consisted of an interrogator, transponder, control and display console, and government-furnished antennas and computer. The system operated on the principle that a continuous-wave signal modulated onto a radio-frequency carrier and propogated through free space undergoes a phase shift that can be measured to provide slant range. Test results conclusively indicate that the system provides more-than-adequate accuracy for the ranging requirements of a VTOL landing guidance system.