A unique approach to wavefront calibration

Significant progress has been made in recent years in wavefront technology using Global Positioning System (GPS) simulators. We demonstrate here a novel approach to surpassing some of the limiting obstacles that plague the simulation world in achieving notable carrier-phase parameters. The controlled reception pattern antenna (CRPA) realistically collects and sends the RF downlink data to the antenna electronics (AE) through the natural order of physics through the atmosphere. The dilemma in the simulation environment is to achieve realistic numbers in carrier-phase calibration to mimic a natural RF environment. We found that a unique approach is to characterize the AE under test by using a vector network analyzer that measures the RF delays between the reference node in relation to the six auxiliary nodes. This in conjunction with a discriminating carrier-phase receiver technique that outputs the required data files enables our wavefront to achieve results of better than a tenth of a degree of precision in the L1 frequency. The significance of these two pieces of equipment working in unison is to limit the movement of the radio frequency (RF) cables that are connected from the GPS simulators to the AE. Previous methods involved connecting and reconnecting RF cables through combiners and amplifiers that individually added errors to the system. The modification to the original method increased calibration accuracy thus better emulating the actual RF environment.