1. Mini-RF Requirements Overview
Mary Reden
NASA/GSFC SGT, Inc.
August 16-17, 2005

2. Mini-RF Overview
Mini-RF is a NAWC/WD-provided synthetic aperture radar technology demonstration provided to the LRO spacecraft for the purpose of demonstrating new radar technology for future use in planetary resource mapping.
Mini-RF is composed of the following major elements:
Fixed planar antenna with dimensions 125 x 75 x 5.5 cm
Electronics box with dimensions 14.2 x 20.3 x 12 cm
Cable harnessing between the electronics box and the antenna,
and to spacecraft electrical interfaces.
Mini-RF is the second in a spiral technology development effort, preceded by the Forerunner radar to be placed into Lunar orbit aboard the Chandrayaan-1 satellite.
Mini-RF will make a series of measurements to demonstrate enhanced technology capabilities over the Forerunner instrument.

3. Mini-RF Block Diagram

4. LRO Requirements Document Flow

5. Mini-RF Level 1 Requirements
Mini-RF Level 2 requirements are defined, and are traceable to a single Level 1 requirement:
LRO Program Requirements Document, #ESMD-RLEP-0010
RLEP-LRO-P160 Technology Demonstration - The LRO shall accommodate the NAWC provided Mini-RF device in order to provide the opportunity for demonstration of this technology in the lunar orbital environment provided it does not increase the project cost, delay the launch date, adversely impact the achievement of full mission success, or increase the overall risk posture of the primary mission.

6. Mini-RF Level 2 Requirements
Key mission requirements:
LRO Mission Requirements Document (MRD), #431-RQMT
LRO Mission Concept of Operations Document, #431-OPS
Mini-RF Requirements and Goals Document, #431-RQMT
Key performance assurance requirements:
Generic Instrument Performance Assurance User's Guide, #430-HDBK
Tailored for Mini-RF to specifically address those areas that may adversely impact the achievement of full mission success, increase the overall risk posture of the primary mission, or have safety implications
Key verification requirements:
LRO Electrical Systems Specification, #431-SPEC
LRO Mechanical Systems Specification, #431-SPEC
LRO Thermal System Specification, #431-SPEC
LRO SpaceWire Specification, #431-SPEC
LRO Technical Resource Allocation Specification, #431-SPEC

7. Mini-RF Requirements Implementation
Implementation of the Mini-RF requirements:
Mini-RF Spacecraft Mechanical ICD, #431-ICD
Mini-RF to Spacecraft Thermal ICD, #431-ICD
Mini-RF to Spacecraft Electrical ICD, #431-ICD
Mini-RF to Spacecraft Data ICD, #431-ICD

8. Driving Requirements on the Spacecraft
Mechanical
The spacecraft shall maintain a Mini-RF mass allocation of 12 kg, including margin
The spacecraft shall mount the Mini-RF antenna such that the antenna normal is ~45-degree off-nadir, on the anti-sun side of the spacecraft
Thermal
The spacecraft shall provide survival heater switch service to maintain the Mini-RF devices within the following temperature limits:
-34 to +71 C for electronics
-160 to +100 C for antenna

9. Driving Requirements on the Spacecraft
Electrical
The spacecraft shall provide 2 and 5 amp 28 v power services
The spacecraft shall provide a SpaceWire interface directly to the Solid State Recorder
The spacecraft shall accommodate a data transfer rate of 8 Mbps (nominal) up to 32 Mbps (maximum) during data collections
Operational
The spacecraft shall provide Mini-RF with a minimum of 12, 4-minute data collection opportunities over the LRO nominal 1-year mission
Mini-RF desires 2 successive orbits in each of 6 modes (S/X-bands, dual/quad polarization, mapping/zoom resolution)
Additional data collects at the lunar poles, bi-static radar operations and off-nadir pointing will be documented in the Concept of Operations Document as desirable targets of opportunity

10. Mini-RF Constraints
The Mini-RF antenna and electronics box shall be thermally isolated from the spacecraft
Accommodation of Mini-RF on LRO shall not interfere with achievement of full mission success, or increase the overall risk posture of the primary mission
Mini-RF shall not interfere with LRO S/C S-band and Ka-band operations
Mini-RF waveform and electronics shall be designed to eliminate any interference with spacecraft S-band operations
Impact of interference shall be minimized by limiting, if necessary, the duration of Mini-RF collection intervals
Mini-RF operations shall be deconflicted with LROC scenes and with the S/C communications timeline
Data collection orbits will be infrequent and will be chosen to accommodate LRO mission constraints.