Lunar Reconnaissance Orbiter
Ground System Requirements
NASA’s Goddard Space Flight Center
22 - 1
LRO Ground System Document Tree
(Key Ground System Requirements Documents)
LRO Level 1 Requirements
Development Document
Level 1
LRO Mission Requirements
Document
LRO Mission Concept of
Operations
(431-RQMT-000004)
(431-OPS-000042)
Level 2
Detailed Mission Requirements
(431-RQMT-000048)
3.1 Ground Network
3.2 Testing and Verification
3.3 Mission Operations Center
3.4 Communications
3.5 Data Distribution
3.6 Flight Dynamics
Level 3
Mission Operations
Center
Specifications
(431-SPEC-000055)
NASA’s Goddard Space
Flight Center
Ground Network
Specifications
ITOS
Specifications
Trending
Specifications
(431-SPEC-000056)
(431-SPEC-000057)
(431-SPEC-000059)
Mission Planning
System
Specifications
Flight Dynamics
Ground System
Specifications
(431-SPEC-000060)
(431-SPEC-000063)
Level 4 22 - 2
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Ground Networks General Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-039
MRD-041
MRD-121
MRD-151
431-RQMT-000048
3.1.1.4
DMR-4
Ground network shall provide S-Band tracking (Doppler and
Ranging) for a minimum of 30 minutes per orbit.
Complies – all ground stations
supporting LRO will have the
capability to provide tracking data
for orbit determination.
431-RQMT-000048
3.1.1.6
DMR-6
The ground network shall send tracking data measurements to
flight dynamics equal to or less than every 5 minutes during
early mission phase.
Complies – the ground network
will either send the tracking data
in real-time or send tracking files
every 5 minutes during early
mission support.
431-RQMT-000004
MRD-122
MRD-151
MRD-152
431-RQMT-000048
3.1.1.7
DMR-7
The S-Band system shall support a command uplink rate of 4
kbps using the S-Band frequency of 2091.3967 MHz.
Complies – the ground network
shall support a command uplink
rate of 4 kbps.
431-RQMT-000004
MRD-039
MRD-041
MRD-121
MRD-151
431-RQMT-000048
3.1.1.8
DMR-8
The S-Band system shall provide tracking data with an
accuracy equal to or less than 8 mm/sec (TBR).
431-RQMT-000048
3.1.1.9
DMR-9
The S-Band system Doppler measurement samples shall be
performed over a 10 second integration period.
Complies – all ground stations will
be capable of supply tracking
data at the accuracy and
frequency needed for flight
dynamics processing.
NASA’s Goddard Space Flight Center
22 - 3
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Ground Networks General Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Requirement
431-RQMT-000004
MRD-039
MRD-041
MRD-121
MRD-151
431-RQMT-000048
3.1.1.10
DMR-10
The S-Band system shall provide Range tracking data with
an accuracy equal to or less than 15 meters.
431-RQMT-000048
3.1.1.11
DMR-11
The S-Band system range measurement samples shall be
collected every 40 seconds.
431-RQMT-000004
MRD-155
MRD-136
MRD-138
431-RQMT-000048
3.1.1.15
DMR-15
The combination of different ground stations within all
supporting networks shall provide at least two separate SBand ground stations to perform telemetry capture,
command uplink, and tracking functions during all mission
critical activities.
NASA’s Goddard Space Flight Center
Concept/Compliance
Complies – the ground network
will send range tones on the
uplink and receive the turnaround tones from the spacecraft.
Ranging shall have an accuracy
of 15 meters or less and be
measured every 40 seconds.
Complies – the ground network
consist of 6 separate ground
stations. DSN will also provide
backup capability throughout the
mission. All mission critical
activities shall have redundant
station coverage.
22 - 4
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(White Sands Complex Ground Station Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-038
MRD-124
MRD-136
MRD-150
431-RQMT-000048
3.1.2.1.1
DMR-19
The Ka Band system shall support variable downlink rates
up to a maximum rate of 100 Mbps using the Ka-Band
frequency of 25.65 GHz.
Complies – the WSC ground
station shall have variable KaBand receivers that can support
the 100 Mbps and lower rates.
431-RQMT-000004
MRD-126
MRD-150
MRD-151
MRD-152
431-RQMT-000048
3.1.2.1
DMR-18
The S/Ka Band ground station shall support simultaneous
S and Ka band frequency
Complies – The WSC ground
antenna will have a dual feed S
and Ka system that will allow
simultaneous S and Ka
operations.
431-RQMT-000004
MRD-121
MRD-150
431-RQMT-000048
3.1.2.1.2
DMR-20
The Ka Band system shall support a receive G/T of not
less than 45 dB/K in the presence of full lunar noise
Complies – The WSC ground
station shall meet or exceed the
45 dB/K Ka-Band receive
requirement.
431-RQMT-000004
MRD-110
MRD-140
MRD-150
431-RQMT-000048
3.1.2.1.3
DMR-21
The Ka-Band system shall support CFDP operations on the
maximum Ka-Band telemetry rate.
Complies – The WSC ground
station CFDP processor shall
operate at all Ka-Band telemetry
rates for LRO.
NASA’s Goddard Space Flight Center
22 - 5
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(White Sands Complex Ground Station Driving Requirements)
Level 2 Req.
Level 3: Requirements
Concept/Compliance
Paragraph
Requirement
431-RQMT-000004
MRD-123
MRD-151
MRD-152
431-RQMT-000048
3.1.2.1.6
DMR-24
The S-Band system shall support a receive G/T of not less
than 27 dB/K in the presence of full lunar noise.
Complies – The WSC ground
station shall meet or exceed the
27 dB/K receive S-Band
requirement.
431-RQMT-000004
MRD-122
MRD-151
MRD-152
431-RQMT-000048
3.1.2.1.7
DMR-25
The S-Band system shall provide an S-Band transmit EIRP
of not less than 79 dBW.
Complies – The WSC ground
station shall have 2 kW
transmitter that allows the
antenna to meet the 79 dBW
EIRP.
431-RQMT-000004
MRD-042
MRD-043
MRD-136
431-RQMT-000048
3.1.2.2.3
DMR-30
The ground station shall timetag all commands transmitted
on the S-Band uplink and forward the time stamp to the
MOC using the status packets as defined in the LRO
Ground System Interface Control Document (431-ICD000049)
Complies – The WSC ground
station will contain a time capture
unit for commands. Information
will be included in general station
status packets.
NASA’s Goddard Space Flight Center
22 - 6
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(S-Band Network Ground Station Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-123
MRD-136
MRD-151
MRD-152
431-OPS-000042
4.4.2
431-RQMT-000048
3.1.3.1.1
DMR-33
The S-Band system shall support a maximum downlink
rate of 300 kbps during early mission phase (Launch and
Early Cruise Phase).
Complies – the S-Band network
shall support the 300 kbps and
lower rates and forward the data
in real-time to the MOC.
431-RQMT-000004
MRD-123
MRD-136
MRD-151
MRD-152
431-OPS-000042
6.2.5
431-RQMT-000048
3.1.3.1.2
DMR-34
The S-Band system shall support a maximum downlink
rate of 128 kbps during the nominal mission phases using
the spacecraft HGA.
Complies – the S-Band network
provides enough link margin to
support the 128 kbps telemetry
rate during the nominal mission
and forward the data in real-time
to the MOC.
431-RQMT-000004
MRD-123
MRD-150
MRD-151
431-RQMT-000048
3.1.3.1.3
DMR-35
The S-Band system shall support a receive G/T of not
less than 20.3 dB/K (TBR) in the presence of full lunar
noise.
Complies – the S-Band network
shall meet or exceed the 24 dB/K
receive requirement.
NASA’s Goddard Space Flight Center
22 - 7
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(S-Band Network Ground Station Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-122
MRD-150
MRD-151
431-RQMT-000048
3.1.3.1.4
DMR-36
The S-Band system shall provide an S-Band transmit
EIRP of not less than 79 (TBR) dBW.
Complies – the S-Band network
transmitters will be upgraded to
support the EIRP requirement of
79 dBW.
431-RQMT-000004
MRD-042
MRD-043
MRD-136
431-RQMT-000048
3.1.3.2.3
DMR-40
The S-Band ground network shall provide at least one
station capable of time stamping all commands
transmitted on the S-Band uplink and forward the time
stamp to the MOC using the status packets as defined in
the LRO Ground System Interface Control Document
(431-ICD-000049)
Complies – The time capture unit
will be deployed to one of the
ground stations for
backup/redundant capability.
NASA’s Goddard Space Flight Center
22 - 8
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Emergency/Backup Network Ground Station Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
The Deep Space Network (DSN) shall provide a ground
network capable of performing S-Band TT&C through the
spacecraft omni antenna and supporting the higher SBand telemetry rates through the HGA.
Complies – DSN capabilities
allow TT&C through either the
Omni or HGA at all different SBand telemetry modes.
431-RQMT-000004
MRD-122
MRD-123
MRD-138
MRD-136
MRD-151
MRD-152
431-OPS-000042
6.2.5
431-RQMT-000048
3.1.4.1
DMR-42
431-RQMT-000004
MRD-123
MRD-138
MRD-151
MRD-152
431-RQMT-000048
3.1.4.1.1
DMR-43
The S-Band system shall support a receive G/T of not
less than 31.53 dB/K (TBR) in the presence of full lunar
noise.
Complies – DSN S-band system
shall meet or exceed the 31.53
dB/K receive requirement.
431-RQMT-000004
MRD-122
MRD-138
MRD-151
MRD-152
431-RQMT-000048
3.1.4.1.2
DMR-44
The S-Band system shall provide an S-Band transmit
EIRP of not less than 87.78 (TBR) dBW.
Complies – DSN S-Band system
shall meet or exceed the 87.78
dBW EIRP requirement.
The LRO Ground System team
will work with DSN to develop an
operations agreement and
support plan.
NASA’s Goddard Space Flight Center
22 - 9
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Mission Operations Center Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-155
MRD-136
MRD-141
MRD-142
431-RQMT-000048
3.3.1
DMR-50
The LRO MOC shall perform orbiter telemetry and
command, mission planning, trending and paging, data
storage and distribution functions required to support all
mission phases.
Complies – The MOC will
provide separate systems for
T&C, trending, mission planning,
paging, data storage and
distribution.
431-RQMT-000004
MRD-056
431-RQMT-000048
3.3.1.5
DMR-57
Details of the LRO command data formats and coding shall
have restricted access.
Complies – the ground system
team will limit access to
command database and control
command format documents.
The ground system security team
is also working with the project
and GSFC’s Space Asset
Protection Team to ensure that
appropriate measures are in
place to protect LRO from
intentional or unintentional
disruption, exploitation, or attack.
431-RQMT-000004
MRD-141
MRD-144
431-RQMT-000048
3.3.2.1
DMR-58
NASA’s Goddard Space Flight Center
The T&C system shall forward all commands to the orbiter
via the ground network during flight.
Complies – The MOC T&C
system will generate and forward
all commands to the orbiter.
Ground network will be
configured to accept commands
from only the T&C system.
22 - 10
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Mission Operations Center Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-136
MRD-141
431-RQMT-000048
3.3.2.2
DMR-59
The T&C system shall provide the interface to the LRO
orbiter during pre-launch I&T and flight operations.
Complies – The T&C system
shall be used during spacecraft
and orbiter I&T. The MOC will
have communication interfaces
to I&T facilities for testing and
training.
431-RQMT-000004
MRD-155
MRD-136
MRD-141
431-RQMT-000048
3.3.2.7
DMR-64
The T&C System shall decomm real-time housekeeping
data and monitor health and safety of the orbiter.
Complies – The T&C system
shall receive and decomm all
real-time housekeeping data for
health and safety monitoring.
431-RQMT-000004
MRD-110
MRD-140
431-RQMT-000048
3.3.2.8.1
DMR-65
The T&C system shall be compatible with CCSDS AOS
version 2 telemetry.
431-RQMT-000048
3.3.2.8.2
DMR-66
The T&C system shall be compatible with CCSDS
Telecommand format.
431-RQMT-000048
3.3.2.8.3
DMR-67
The T&C system shall support the CCSDS COP-1 protocol
Complies – The T&C system
shall provide command and
telemetry handling that complies
with the CCSDS standards for
the exchange of telemetry and
commands. The T&C system
shall also use CCSDS COP-1
protocol for reliable commanding.
NASA’s Goddard Space Flight Center
22 - 11
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Mission Operations Center Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-140
MRD-141
MRD-150
431-RQMT-000048
3.3.2.9
DMR-68
The T&C system shall support remote configuration and
control of the CFDP processor located at the White Sands
ground station.
Complies – The T&C system
shall support remote
configuration and control of the
CFDP processor at WSC. The
CFDP processor will be an
module added to the current T&C
system.
431-RQMT-000004
MRD-138
431-RQMT-000048
3.3.1.6
DMR-58
The ground system shall develop and maintain a backup
control center facility to monitor and maintain orbiter
health and safety.
Complies – The ground system
is planning to perform a trade
study to select the best location.
The backup MOC will contain
limited capability, only those
systems required to maintain
mission health and safety.
431-RQMT-000004
MRD-136
MRD-118
431-RQMT-000048
3.3.7.1
DMR-200
The flight operations team shall be required to respond to
an orbiter emergency within 2 hours.
Complies – The operations team
staffing and support plan will
respond to all anomalies within 2
hrs.
NASA’s Goddard Space Flight Center
22 - 12
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Flight Dynamics Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
431-RQMT-000004
MRD-136
MRD-149
431-RQMT-000048
3.6.1.2
DMR-278
Concept/Compliance
Requirement
Flight Dynamics Facility and Flight Dynamics Analysis
Branch shall provide mission products as defined in the
Lunar Reconnaissance Orbiter Ground System Interface
Control Document (431-ICD-000049).
Complies – Flight Dynamics shall
generate required mission
products to support mission
planning and data processing.
Implementation details for
mission products are not yet
defined but will be documented in
the LRO Ground System
Interface Control Document
(431-ICD-000049).
431-RQMT-000004
MRD-147
MRD-148
431-RQMT-000048
3.6.2
DMR-279
Flight Dynamics Facility (FDF) shall provide OD support
to LRO through all mission phases.
Complies – Flight Dynamics
Facility shall ingest tracking data
and generate updated orbit state
vector to support the LRO
mission.
431-RQMT-000048
3.6.2.2
DMR-281
FDF shall perform OD processing each day (TBR),
Sunday through Saturday, and after any orbiter
maneuver.
Complies – Flight Dynamics
Facility will perform orbit
determination seven times per
week using the previous ~48
hours of tracking data.
NASA’s Goddard Space Flight Center
22 - 13
Lunar Reconnaissance Orbiter (LRO)
Ground System Level 2 Flow Down Key
Requirements
(Flight Dynamics Driving Requirements)
Level 2 Req.
Level 3: Requirements
Paragraph
Concept/Compliance
Requirement
431-RQMT-000004
MRD-148
431-RQMT-000048
3.6.3
DMR-282
FDF shall provide AD support to LRO through all mission
phases.
Complies – Flight Dynamics
Facility shall provide attitude
determination support throughout
the mission including orbiter
slews planning, attitude
verification, and calibrations.
431-RQMT-000004
MRD-146
431-RQMT-000048
3.6.4
DMR-285
The Flight Dynamics Analysis Branch shall provide
trajectory and maneuver support to LRO through all
mission phases.
Complies – The Flight Dynamics
Analysis Branch (FDAB) shall
provide trajectory and orbit
trending and planning. FDAB will
plan all trajectory, orbit, stationkeeping, and momentum
maneuvers.
NASA’s Goddard Space Flight Center
22 - 14
Ground System Architecture Overview
High Gain
Antenna
Instrument
Module
S-Band
Cmd & Tlm
X
Mission Operations Center
Orbiter Cmds
S-Band Sites
Avionics
Module
Propulsion
Module
T&C System
Trending System
Y
Z
ULTRAFLEX
Solar Array
S-Band
Cmd & Tlm
S-Band
Cmd & Tlm
Real-Time Housekeeping
Telemetry
S-Band
System
LRO WSC
Ground
Station
Ka-Band
Tlm
Tracking
Data
Ø
Ø
Ø
Plan daily events
Create event plans
Generate daily
loads
Display short/long
term planning
events
Web viewable
timeline
Ø
Flight Dynamics
Products
Ø
Mission
Products
Central storage
system
Accessible for all
systems
Short/Long term
storage
Ø
Mission Planning
Spacecraft
Telemetry
Acq.
Data
Data Storage
Ø
Stored Housekeeping
Data Files
Ground Network
Ingest raw data
Trend data points
Produce plots and
reports
Remote access
Ø
Stored Measurement
Data Files
S-Band
System
Laser
Ranging
Network
Laser
Ranging
S-Band
System
Ø
Ø
Ka-Band
System
Deep Space
Network
Ø
CFDP Control
And Status
Ø
Ø
Ø
ITOS/CFDP
Telemetry
Monitoring
Command
Management
Automated
Operations
CFDP processing
Ø
Station Status
Packets
Ø
Data Distrbution
Ø
Ø
Distribute
measurement data
Distribute mission
products
Mission
Products
Flight Dynamics
Mission
Products
Mission
Products
Orbit
Determination
Attitude
Determination
HK
Tlm
Mission
Products
Maneuver
HK
Tlm
Mission
Products
HK
Tlm
Mission
Products
Legend
LOLA
SOC
LAMP
SOC
(GSFC)
(SwRI, CO)
Measurement
Products
Measurement
Products
Delayed/Post-processing Link
Real-time Link
LEND
SOC
(Moscow,
Russia)
LROC
SOC
Diviner
SOC
CRaTER
SOC
(Univ. NW)
(JPL)
(Univ. Boston)
Measurement
Products
Measurement
Products
Measurement
Products
Measurement
Products
Mini-RF
(APL)
LRO Ground System Element
NASA’s Goddard Space Flight Center
External Interfaces
Planetary Data System (PDS)
22 - 15
Ground System Preliminary Verification
Approach
•
Ground system verification and readiness will be performed through a series of
ground system verification tests, operations tests and simulations.
Test Level
Level 3
Level 4
Test Type
Description
Ground System Readiness Tests
•Verifies integration of the ground system elements by interface data flows between the
elements through to the full integrated end-to-end validation.
•Demonstrates/proves that the ground system satisfies the level 3 requirements.
•Demonstrates element-to-element interfaces as defined in the ground system ICD.
•Establishes ground system compatibility with orbiter and external systems.
RF Compatibility Tests
•Verifies links between the spacecraft and ground networks during orbiter integration.
Ground Network Tracking
Certifications
•Flight dynamics will provide tracking certifications on all new or upgraded ground
network sites.
•Verifies tracking requirements are met.
Mission Operations Simulations
•Small simulations focus mostly for the flight operations team that covers all mission
phases.
Mission Rehearsals
•Full simulations with all mission team personnel. Rehearsals will cover all critical
events throughout the mission.
Element Level Tests
•Software/Hardware provider system testing based on level 4 specs
Acceptance Tests
•Acceptance testing to verify system functionality and performance based on level 4
specs.
Operations Readiness Exercises
•Simulations focus at the procedure/activity level that will verify the operations team
individual flight procedures and activities.
NASA’s Goddard Space Flight Center
22 - 16
Summary
• A baseline mission concept of operations for the mission and
ground system have been developed
• Current LRO Ground System concept supports the LRO
development schedule and Mission concepts
• Additional ground system reviews will be performed
• Ground System Requirements Review
• Ground System Design Review
Ground System requirements are sufficiently defined and the design is ready to
proceed to detailed ground system requirements and design review
NASA’s Goddard Space Flight Center
22 - 17