GPS Clocks in Space: Current Performance and Plans for the Future

reportActive / Technical Report | Accession Number: ADA484558 | Open PDF

Abstract:

The ITT Industries-developed GPS IIR satellite payloads have been on-orbit since 1997 providing outstanding signal-in-space performance. Much of credit for this outstanding performance can be given to the GPS IIR Time Keeping System TKS and the GPS-IIR spacecraft bus, which keeps the payload in a mechanically and thermally stable condition. A key component of the TKS system is PerkinElmers rubidium atomic frequency standard RAFS. We now have a grand total of 15 years of on-orbit experience with the GPS IIR and . In this paper we will present the current on-orbit performance of GPS IIR TKS and RAFS. Since GPS IIR, ITT and PerkinElmer have made significant performance enhancements to the TKS and RAFS. This paper will highlight performance of the next generation TKS with the enhanced RAFS ERAFS and an improved precision phase meter PPM. The paper discusses current on-orbit performance of the GPS IIR TKS and RAFS and shows that they match expectations. The paper also discusses the modifications that comprise the ERAFS and associated performance improvement over the legacy RAFS. Finally, the paper discusses potential performance enhancements for the next generation TKS.

Author(s):
Dass, Todd ; Freed, Gerald ; Petzinger, John ; Rajan, John ; Lynch, Thomas J. ; Vaccaro, John
Author Organization(s):
ITT INDUSTRIES AEROSPACE CLIFTON NJ COMMUNICATIONS DIV
Descriptive Note:
Conference paper
Supplementary Note:
See also ADM001507. Presented at Annual Precise Time and Time Interval (PTTI) Planning Meeting (34th), held on 3-5 December 2002, in Reston, VA. The original document contains color images. Prepared in cooperation with PerkinElmer Optoelectronics, Salem, MA.
Pagination:
0019

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Monitor Series:
NIMA/REST
 Subject Terms
Joint Capability Areas:
JCA_5_Command and Control; JCA_4.6_Engineering; JCA_4.6.1_General Engineering; JCA_6_Net Centric; JCA_6.4.1_Secure Information Exchange; JCA_6.1.3_Switching and Routing; JCA_6.3.3_Spectrum Management; JCA_1.4.2_Health Service Delivery; JCA_1.4_Force Support; JCA_6.4_Information Assurance; JCA_8_Building Partnerships; JCA_5.3_Planning; JCA_6.1_Information Transport; JCA_6.3_Net Management; JCA_8.2_Shape
Modernization Areas:
Space
Communities of Interest:
Space
Descriptor(s):
*ORBITS, *GLOBAL POSITIONING SYSTEM, *ARTIFICIAL SATELLITES, RUBIDIUM, FREQUENCY STANDARDS, ATOMIC CLOCKS, THERMAL STABILITY, PAYLOAD, MEASURING INSTRUMENTS
Field(s)/Group(s):
Celestial Mechanics, Navigation and Guidance
Keyword(s):
TKS(TIME KEEPING SYSTEM), RAFS(RUBIDIUM ATOMIC FREQUENCY STANDARD), PPM(PRECISION PHASE METER)
Report Date:
2002 Dec 01
Creation Date:
2008 Aug 20