Assessment of the Expansion of the Earth Exploration-Satellite Service in the 8025-8400 MHz Range

Copies of this report may be obtained from the author, Phil Gawthrop, at (202)482-3203, or [email protected] or write:

Phillip Gawthrop
NTIA, Room 6725
1401 Constitution Avenue, N.W.
Washington, DC 20230

NTIA TM 97-339

ASSESSMENT OF THE EXPANSION OF THE EARTH
EXPLORATION-SATELLITE SERVICE
IN THE 8025-8400 MHz RANGE

Philip E. Gawthrop

U.S. DEPARTMENT OF COMMERCE

William M. Daley, Secretary

Larry Irving, Assistant Secretary
for Communications and Information, and
Administrator, National Telecommunications
and Information Administration

June 1997

EXECUTIVE SUMMARY

This report contains the results of an NTIA study concerning the use of the Earth exploration-satellite service (EESS) in the frequency range 8025-8400 MHz for Government, non-Government and international operations. The intent of this report was to compile the current and proposed, national and international, spectrum usage in the 8025-8400 MHz frequency range (including the lower adjacent-band, 7900-8025 MHz, and the upper adjacent- band, 8400-8450 MHz), to identify potential sharing issues, and summarize some options available to alleviate the interference interaction that might occur. This report is intended to be a resource document for examining specific EESS issues within the frequency range of 8025-8400 MHz.

The EESS in the 8025-8400 MHz frequency range is expected to increase dramatically in the near future with the increased spectrum requirements of the LANDSAT satellite system, the NASA Earth Observing System (EOS), and systems proposed by four U.S. commercial entities (the AstroVision Incorporated, the Space Imaging LP, the Orbital Sciences Corporation, and the EarthWatch Incorporated). Other Administrations (e.g., France, Japan, Canada, India, Russia, South Africa, and the Ukraine) have or plan to have EESS systems that operate in the 8025-8400 MHz frequency range. Another anticipated change in use of the 8025-8400 MHz range is a result of the reallocation study [Spectrum Reallocation, 95] completed in February 1995. This reallocation study will necessitate moving of certain Government fixed services from the 2 GHz range into the 7/8 GHz range.

United States Government and numerous non-Government entities will launch EESS systems operating in the 8025-8400 MHz frequency range based on the policy directive on remote sensing space capabilities signed by the President (see Appendix¾A for the news release from the Commerce News). With the introduction of new and increased use of the EESS systems in that range, harmful interference among the various users of these and adjacent bands may occur. Nine potential interference scenarios involving combinations of EESS earth and space stations, MSS aircraft and FSS earth stations, fixed stations, space research earth stations, and future meteorological-satellite (MetSat) earth and space stations have surfaced. If existing standards and limits are adhered to, the majority of the interactions dealing with known Government services should be manageable.

The planned MetSat use of the 8025-8400 MHz frequency range may require further electromagnetic compatibility analyses between this service and existing services. Further analysis may also be necessary based on the reallocation study of 1995. The use of 30 cm diameter earth stations in the EESS or a large number of relatively small diameter EESS earth stations is a significant sharing issue with respect to terrestrial and other space services. These relatively inexpensive earth station antennas are being investigated for worldwide dissemination and will likely require further study. The 30 cm proposal will not be addressed in this report.

ABSTRACT

This report assesses the expansion of the Earth exploration-satellite service in the 8025-8400 MHZ frequency range. The report identifies allocations, standards, regulations and current and planned spectrum usage applicable to this range for Government, non-Government, and international operations. In addition, various potential interference scenarios among the EESS systems and the various other services (operating in this range) are identified.

U.S. Government and non-Government entities will launch Earth exploration-satellite service (EESS) systems in the 8025-8400 MHZ frequency range based on the policy directive on remote sensing space capabilities signed by President Clinton (attached in Appendix¾A; this policy is dictated by public law, Land Remote Sensing Policy Act of 1992). With the introduction of new and increased use of the EESS systems in that range, the potential for harmful interference exists among the various users of these and adjacent bands. NASA, among other Government agencies, is concerned by Earth exploration-satellite service use in the 8025-8400 MHZ frequency range in today's as well as future markets. One method of monitoring the use of the 8025-8400 MHZ frequency range by Earth exploration-satellite services is the Space Frequency Coordination Group (SFCG), (September 1994) of which NASA and NOAA are members.

KEY WORDS

8025-8400 MHz BAND

FIXED-SATELLITE SERVICE (FSS)

MOBILE-SATELLITE SERVICE (MSS)

EARTH EXPLORATION-SATELLITE SERVICE (EESS)

METEOROLOGICAL-SATELLITE SERVICE (MetSat)

FIXED SERVICE

ACKNOWLEDGEMENT

NTIA acknowledges the support and cooperation of the NASA X-Band Workshops, specifically the two Co-Chairmen, Mr. Joseph Deskevich and Mr. David Struba. NTIA also appreciates the efforts of several key manufacturers in providing the domestic satellite system information contained herein: AstroVision Incorporated, Space Imaging LP, Orbital Sciences Corporation (OSC), Resource 21, and EarthWatch Incorporated. Their technical expertise was helpful in gaining an understanding of these satellite system operations.

GLOSSARY of TERMS and ACRONYMS

ADEOS		Japanese satellite
AF		Air Force
AR		Army
ARTCC		Air Route Traffic Control Centers
ATC		Air Traffic Control
AVSAT-1		Geostationary satellite of AstroVision
BPSK		Bi-Phase Shift Keying
BW		Authorized Bandwidth
bins		Example: 10 MHz Bins = a list of frequencies 7910-7920, 7920-7930 MHz, etc.
CG		Coast Guard
CDMA		Code Division Multiple Access
CRSS		Commercial Remote Sensing System satellite of the Space Imaging LP
dBi		decibels relative to an isotropic antenna
dBm		decibels relative to a milliwatt
dBW		decibels relative to a Watt
dBW/Hz		decibels relative to a Watt per Hertz
dB(W/m2)	decibels relative to Watts per meter squared
DISA		Defense Information System Agency
DOC or C	Department of Commerce (defined as C in the GMF)
DoD		Department of Defense
DOE		Department of Energy
DOI or I	Department of Interior (defined as I in the GMF)
DOJ or J	Department of Justice (defined as J in the GMF)
DOT or T	Department of Treasury (defined as T in the GMF)
DSCS		Defense Satellite Communications System satellite
DSN		Deep Space Network
Early Bird	An EarthWatch satellite(s)
EESS		Earth exploration-satellite service
EIRP		equivalent isotropically-radiated power
EOS		Earth Observing System
EOS AM series	EOS satellite crossing the equator southbound at 10:30 am
EOS PM series	EOS satellite crossing the equator northbound at 1:30 pm
EOS CHEM series	EOS satellite named for its measurement of atmospheric chemistry
ENVISAT-1	French satellite
ERS-1, -2	French satellites
ESA		European Space Agency
EYEGLASS	Orbital Science Corp. satellites
FAA		Federal Aviation Administration
FCC		Federal Communications Commission
fd		Displacement Frequency
FDM		Frequency Division Multiplex
FDMA		Frequency Division Multiple Access
FDM/FM		Frequency Division Multiplex/Frequency Modulation
FLTSATCOM	Fleet Satellite Communications
FSS/MSS		Fixed-Satellite Service/Mobile-Satellite Service
GEO satellite	Geostationary satellite
GMF		Government Master File
GREENSAT-1	South African satellite
GREENSENSE	South African satellite
IDCSP		Initial Defense Communications Satellite Program
I/N		Interference-to-Noise Ratio
IPO		Integrated Program Office
IRAC		Interdepartment Radio Advisory Committee
IRS-1A, 1B, 1C	India satellites
ITU		International Telecommunication Union
ITU-R		International Telecommunication Union-Radiocommunications Sector
ITU-R IS.###	ITU-R Inter-Service Sharing and Compatibility Series
ITU-R SA.###	ITU-R Space Applications Series
JERS-1		Japanese satellite
JPL		Jet Propulsion Laboratory
LEASAT		low Earth satellite system owned by DOC/NOAA
LEO satellite	Low Earth Orbiting satellite
LANDSAT-4,-5,-6	DOC/NOAA satellites
LANDSAT-7	NOAA/NASA/AF satellite
LOS		Line Of Sight
Mbps		Megabits per second
METOP		Meteorological Operational Satellite
MetSat		Meteorological-Satellite
Mchip		Megachip
MOS-1, 1B	Japanese satellites
MSS		Mobile-Satellite Service
N		Navy
NASA		National Aeronautics and Space Administration
NATO		North American Treaty Organization
NOAA		National Oceanic and Atmospheric Administration
NPOES		National Polar Orbiting Operational Environmental Satellite
NSF		National Science Foundation
NTIA		National Telecommunications and Information Administration
OQPSK		Off-set Quadrature-Phase Shift Keying
OSC		Orbital Sciences Corporation
PFD		Power Flux Density
POEM 1		French satellite
ppm		Parts per million
PSK		Phase Shift Keying
QPSK		Quadrature-Phase Shift Keying
RADARSAT-1A	Canadian satellite
RCL		Radar Communications Link
REC		Recommendation associated with SFCG
RF		Radio frequency
RR		Radio Regulations
SFCG		Space Frequency Coordination Group
SITCH		Ukrainian satellite
SQPSK		Staggered Quadrature-Phase Shift Keying
SPEKTR-R	Russian satellite
SPD		Spectral Power Density
SPOT 1-6	French satellites
SPS		Spectrum Planning Subcommittee 
SRA		Spectrum Resource Assessments
SRV		Spectrum Resource file
SSIPR		Russian satellites
SSMA		Spread Spectrum Multiple Access
TDRSS		Tracking and Data Relay Satellite System
TT & C		Tracking, Telemetery and Control
TVA		Tennessee Valley Authority
US & P		United States and Possessions
VA		Department of Veterans Affairs
WARC		World Administrative Radio Conference
WRC		World Radiocommunication Conference
X-Band		bands of 8,000-12,000 Mhz
XXM		French/European Space Agency satellite