GPS Block IIF Atomic Frequency Standard Analysis

Abstract : The first Global Positioning System (GPS) Block IIF space vehicle (SV) was launched on 28 May 2010 with one Digital Cesium Beam Frequency Standard (DCBFS) and two Rubidium Frequency Standards (RFS) onboard. The DCBFS was manufactured by Symmetricom and the RFS was manufactured by PerkinElmer Optoelectronics. This paper will present a performance analysis of the early test operation of the DCBFS and the initial operation of the RFS. The early orbit data of these two GPS Block IIF space clocks will be compared to the Life Test data from Block IIF flight-qualified DCBFS and RFS units evaluated at the Naval Research Laboratory (NRL) prior to space flight. The DCBFS Life Test was conducted with two flight units between August 2004 and October 2006, and the RFS Life Test has been ongoing since August 2008.