# Presentation: 914938

## Section 6

***Hyperion Grating Imaging Spectrometer***

*** ******. . . Steve Carman***
*Hyperion Project Manager*
*TRW Space & Electronics *

## Outline

***Outline***

***Driving Requirements***
***Design Overview******	***
***Performance Requirements***
***Calibration/Characterization***
***Flight Validation***

## Hyperion Driving Requirements

*** ******. . . Steve Carman***
*Hyperion Project Manager*
*TRW Space & Electronics *

## Purpose of Hyperion on EO-1

***Purpose of Hyperion on EO-1***

***Hyperion is the first hyperspectral imager in space, demonstrating this new technology***
***Hyperion will set the standard for hyperspectral imagery, enabling NASA to establish minimum requirements for future data buy***
***Hyperion FOV is coaligned with ALI’s active area to enable cross-calibration of earth scenes with complete spectrum***
***Discrete channels on Landsat and ALI can be checked with Hyperion***
***Comparison with Terra MODIS and ASTER also planned ***
***Hyperion satisfies NASA’s desire to replace the Hyper-Spectral Imager (HSI) that was lost with the Lewis mission.***
***This new technology can provide unique insight into many scientific and commercial disciplines***

## Hyperspectral Imaging Applications & Benefits

**	****	****Existing Satellite****	****	****Capabilities (SPOT,****   Application ****	****	****LandSat)****	****Hyperion Capability****	****Perceived Benefits**
- Mining/Geology	Land cover classification	Detailed mineral	Accurate remote mineral
- 			mapping	exploration
- Forestry	Land cover classification	Species ID	Forest health/infestations
- 			Detail stand mapping	Forest productivity/yield
- 			Foliar chemistry	analysis
- 			Tree stress	Forest inventory/harvest				planning
- Agriculture	Land cover classification	Crop differentiation	Yield prediction/commodities
- 	Limited crop mapping	Crop stress	crop health/vigor
- 	Soil mapping
- Environmental	Resource meeting	Chemical/mineral	Contaminant MappingManagement	Land use monitoring	mapping & analysis	Vegetation Stress

## Hyperspectral and Multispectral Scene Characterization

**Wavelength**

**Measured Reflectance**

- Band 3

- Band 4

- Band 2

- Band 1

**Wavelength**

**Measured Reflectance**

**Wavelength**

**Reflectance**

***Spectral characteristic of scene***

***Hyperspectral Imaging***
***Hundreds of bands ***

***Multispectral Imaging***
***Few bands ***

## Hyperspectral Image Provides Forestry Detail

- Open field

- No Data

- Red Maple

- Red Oak

- Mixed

- Hardwood

- Legend

- Hardwood/

- Conifer Mix

- White Pine

- Hemlock/

- Hardwood Mix

- Mixed Conifer

- Norway Spruce

- Red Pine

- Spruce Swamp

- Hardwood Bog

**LandSat Analysis**

**Hyperspectral Analysis**

- Analysis by Mary Martin  University of New Hampshire

## Hyperspectral Image Provides Geological Data

**Red: Hydro-thermal alteration**

**Red:  Calcite **
**Blue and Green:  Muscovite**

**MULTISPECTRAL ANALYSIS**

**HYPERSPECTRAL ANALYSIS**

**GEOTHERMAL**** ****AREA**
** ****(no specific mineral information)**

**CALCITE**
** ****(gold bearing quartz)**

- Analysis courtesy AIG Limited Liability Company

## Roof Analysis and Mapping Project - Redondo Beach Middle Schools

**Aerial Photo**

**Roof Composition Analysis ****Using Hyperspectral Data**

- Asphalt 1
- Asphalt 2
- Asphalt 3

- Wood
- Tile

*Objective:  Provide detailed map of roof composition clusters for Redondo Beach, CA fire department*

## Hyperion Hyperspectral Imager

*Hyperion is a push-broom imager with:*
*220 10 nm bands covering the spectrum from 0.4 ****m - 2.5 ****m*
*6% absolute radiometric accuracy*
*Image swath width of 7.5 km*
*IFOV of 42.5 ****rad*
*GSD of 30 m at 705 km altitude*
*12-bit image data*
*MTF 0.34 - 0.48*
*Power: 51W orbit avg., 126W peak*
*Mass: 49 kg*

***Hyperion***
***12 months from order to delivery***

- Hyperion Sensor Assembly before Environmental Test
- (5/6/99)

## Hyperion Origins

***Hyperion Origins***

***Following contract termination of planned Grating Imaging Spectrometer (GIS) and Wedge Imaging Spectrometer (WIS) due to technical problems, TRW offered to build Hyperion, a hyperspectral GIS integrated with the Advanced Land Imager (ALI), to be assembled from Lewis Hyperspectral Imager (HSI) spares and delivered to EO-1 in just 12 months***
***Hyperion instrument redefined in first week of project as a stand-alone instrument to simplify EO-1 integration by eliminating integration with ALI ***
***Added foreoptics and structure design based on spares from the Electro Optical Camera (EOC), another TRW instrument program***
***Schedule remained 12 months to delivery***
***Even with a tight one-year schedule, the EO-1 quality requirements and technical design reviews were fully incorporated into the Hyperion program***

## Hyperion Master Schedule

***Even though Hyperion was an extremely fast-paced program, the parts selection and design standards were not compromised. Hyperion met the GSFC/EO-1 program quality requirements, including numerous reviews.***

**VNIR Focal Plane Electronics (FPE)**

- Design

- Procurement

- Fab/Assy/Test

**Electronics Assembly (HEA)**

- Design

- Procurement

- Fab/Assy/Test

- Software

**Optical-Mechanical Subsystem (OMS)**

**...**

**Instrument Test Set (HITS)**

- Design

- Procurement

- Fab/Assy/Check-out

- Software

**System Mechanical Design**

**System Mechanical Fabrication**

**System Assembly & Test**

- Instrument Assembly

- Instrument Test

**Pack & Ship**

- 7 Oct 1998

- Hyperion

- Shipped

- 6 July 99;

- Delivered

- 7 July 99

## Key System Trades & Critical Analyses

***Key System Trades & Critical Analyses***

***Dichroic Beam Splitter Vs. Dual Blazed Grating***
***Selected Dichroic separation of VNIR and SWIR requiring two gratings, improving performance over dual blazed grating***
***Instrument Spectral Bandwidth***
***Trade to maximize signal-to-noise ratio by optimizing the 10nm spectral width and the number of channels***
***Thermal Control of Opto-Mechanical Structure***
***Moved heaters from outside of honeycomb enclosure to the OMS structure inside honeycomb enclosure to save heater power.***
***1553 / 1773 Conversion***
***Selected transceiverless 1553 chip that matched input to EO-1 1773 fiber optic device, avoiding significant expense of developing a separate converter***

## Hyperion Design Overview

*** ******. . . Steve Carman***
*Hyperion Project Manager*
*TRW Space & Electronics *

## Hyperion Functional Block Diagram

- Hyperion Sensor Assembly (HSA)

- Hyperion Electronics Assembly

- Aperture Cover

- Actuator

## Hyperion Subassemblies

- Hyperion
- Electronics
- Assembly
- (HEA)

- Cryocooler
- Electronics
- Assembly
- (CEA)

- Hyperion Sensor Assembly (HSA)

## Hyperion Spacecraft Accommodation

***Hyperion Spacecraft Accommodation***

## Hyperion Performance Requirements

*** ******. . . Steve Carman***
*Hyperion Project Manager*
*TRW Space & Electronics *

## Hyperion Requirements Flowdown

## Hyperion Performance Requirements

**Signal to Noise Ratio (SNR)**

**Modulation Transfer Function (MTF)**

## Hyperion Calibration/Characterization

*** ******. . . Peter Jarecke***
*Hyperion Calibration*
*TRW Space & Electronics *

## FPA Rectilinearity
Cross-Track Spectral Alignment (CTSA)
Spatial Co-Registration of Spectral Channels (SCSC) 
Image Quality
Cross-track and Along-track MTF
Radiometric Responsivity - Calibration
Long Term Repeatablity 
Pixel Center Wavelength Calibration
Signal to Noise
Ground Sample Distance and Swath Width

***FPA Rectilinearity***
***Cross-Track Spectral Alignment (CTSA)***
***Spatial Co-Registration of Spectral Channels (SCSC) ***
***Image Quality***
***Cross-track and Along-track MTF***
***Radiometric Responsivity - Calibration***
***Long Term Repeatablity ***
***Pixel Center Wavelength Calibration***
***Signal to Noise***
***Ground Sample Distance and Swath Width***

***Radiometric Quantities To Be Characterized***

## Overview of Calibration Process

***Overview of Calibration Process***

## Conversion to Radiance

## Spectralon Panel Assembly Installed

- Black Panel Over White Chamber Wall

- FEL 1000 Watt Lamp

- Chamber Window Covered

- Back of Spectralon Panel

- Gold Plated Baffle

## Hyperion Radiometric Characterization Facility

***Hyperion Radiometric Characterization Facility***

- Formerly Known as the MSTB - Upgraded for
- Hyperion Characterization
- Two modes of Operation:
- 1) Pinhole, slit and/or Knife Edge
-     at end of light pipe put at focus
-     of OAP
- 2) End of light pipe is re-imaged onto Spectralon panel.
- Both are shown simultaneously
-       in chart without re-imaging
- 	optics
- Steering mirror is a two axis, fine pointing mirror
- 	( rad) for sub-pixel scanning in spatial dimensions

- The transfer radiometer is a removable box for calibration of the
-    Characterization Facility output.
- It uses a chopped pyroelectric detector traceable to the
-    TRW primary irradiance scale.
- An accurate A is calculated from precision apertures and
-    OAP focal length.

- Chopper

## Spectral Wavelength Calibration

***High resolution scans of the Holmium and Erbium Oxide doped Spectralon are shown in the next chart.***
***Two sensor data frames are taken: one from a doped Spectralon panel and one from a high reflectance Spectralon panel.***
***The ratio of these two frames removes lamp illumination source wavelength variations and sensor response variations. ***
***To derive a calculated curve for the above data, the high resolution scans are convolved with the sensor spectral response function. This degrades the high resolution scans to the lower sensor resolution.***
***A linear least squares (LLS) regression of the data points with the curve fixes the wavelength calibration of the sensor. Each spatial FOV position is calibrated in wavelength simultaneously for all spectral pixels saving time greatly.***
***The linear regression at each FOV position allows three constants for wavelength values at the pixel center (i.e. a second order fit in l versus pixel number). The width of the sensor pixel response function is also allowed to take on a best fit value for the LLS.***
***The accuracy of the fit is about 0.02 pixels (judgement call based on the width of the standard error minimum of the LLS fit)***

## Spectral Wavelength Calibration

***Spectral Wavelength Calibration***

## In-Flight Radiometric Calibration

## On-Orbit Calibration Verification

## Radiometric Long Term Monitoring Plan

## Image Quality

## Image Quality Example

- Vertical and Horizontal MTF can be calculated from diagonal edge

## Spectral Calibration Using Internal Calibration System

***Spectral Calibration Using Internal Calibration System***

- Examples of absorption lines of the white paint

## Hyperion Flight Validation

*** ******. . . Dr. Carol Segal***
*Hyperion Deputy Project Manager, Mission Operations*
*TRW Space & Electronics *

## Hyperion Performance Verification

***The On-orbit Performance Verification Plan was completed in preparation for the on-orbit 60 day checkout period:***

## Hyperion Activation

## On-Orbit Repeatability of Calibration Lamp

- -3

- -2

- -1

- 0

- 1

- 2

- 3

- 0

- 50

- 100

- 150

- 200

- 250

**Minutes of Operation **

**Percent Difference Relative to Lamp **

**associated with Solar Calibration  **

**Event**

- VNIR Band 40: 752 nm

- SWIR Band 150: 1649 nm

- Day 360

- Day 344

- Each point is coincident with a

- Data Collection Event (DCE)

## Hyperion Image of Fairfax, VA December 2000

- Golf Course Turf

- Athletic Field

- Dormant Trees

- Image taken by Hyperion shows the relative chlorophyll content of vegetation in Fairfax County.  The spectral profiles indicate healthy grass in the athletic field and golf course.  The spectral profile of the trees indicates dormant vegetation.

- Oxygen in the atmosphere is detected by the spectral
- profiles in the near infrared wavelength.

## Verrazano-Narrows Bridge, New York

***Verrazano-Narrows Bridge, New York***

## Geometric: Example

**Cordoba Soybean**
- False RGB, Red is healthy vegetation: 51,23,16
- ~(864,578,507 nm)

*VNIR Band 30: ~650 nm*

*VNIR Band 40:  ~752 nm*

*SWIR Band 85:  ~993nm*

*SWIR Band 150:  ~1649 nm*

***Geometric: Example***

## Oahu, HI

## Tariquia, Bolivia

- Visible RGB

- False RGB Representing Pixel Purity