1. Key Milestones Objective Develop a wideband instrument (8 GHz – 40 GHz) in support of Snow and Cold Land Processes (SCLP) mission as defined by the Decadal Survey. Perform both ground (Radar) and airborne experiments (Synthetic aperture radar/radiometry) using wideband passive arrays. Demonstrate improved Snow Water Equivalent measurements from ground and airborne experiments using new processing algorithms. Approach: WISM sensor is a new capability, offering a broadband, multi- function, software reconfigurable instrument. Dipole Layer Balun Layer Combiner Layer Single 8 GHz – 40 GHz feed replaces multiple feeds, reducing size/weight Mission Description Implement a version of Harris’ Current Sheet Array (CSA) antenna technology operating from 8 GHz – 40 GHz Fabricate the passive array, baluns, and power combiners to build the antenna using Polystrata process Utilize Harris’ ongoing Software Defined Radio development to achieve a wideband, software reconfigurable instrument CoIs/Partners: Leung Tsang, Univ. of Washington; Paul Racette, GSFC; Felix Miranda, GRC; Hans-Peter Marshall, Boise State Univ.; Scott Meller, Nuvotronics 1.Review of SAR/Radiometer enhancements 07/14 2.Perform airborne validation of snow measurement 01/15 3.Implement SAR and radiometer frequency expansions 09/16 4.Perform airborne validation of snow-free measurement 10/15 5.Perform airborne validation of peak snow measurement 04/16 6.Data Processing and Final Reporting 03/17 TRL in = 3 TRL current = 3 1

2. Requirements at a Glance TRL in = 3 TRL current = 3 1.Proposed flight dates and hours: Year 1 Campaign, 12 Flight Hours; 01/12/15 – 01/20/15 Year 2 Campaign, 12 Flight Hours; 10/12/15 – 10/20/15 Year 3 Campaign, 12 Flight Hours; 03/31/16 – 04/07/16 2.Location we wish to operate the aircraft: Grand Junction Colorado 3.Drawings/analysis that exist for WISM: See Charts 6 – 15 4.Number of people we wish to fly on the aircraft? 2 – 3 5.Map of flight lines: See Chart 4 for Preliminary Are of Investigation – 15 km x 3 km, details will be provided 1 week prior to campaign 6.Special requirements for the instrument or flight operations (aircraft flight restrictions such as bank angle, requirement for gases or liquids to support the instrument, etc.): See Chart 8 – 9 for preliminary info, details will be provided 1 week prior to campaign 7.Power requirements for the instrument? Radiometer: 28 V, 160 W | Radar: TBD 8.Size of the instrument: See Charts 12 – 13 9.Weight of the instrument and rack components: Approximately 600 lbs – 700 lbs 10.Total number of racks needed: 2 11.Are you using vendor supplied racks: Vendors Supplied Racks 2

3. WISM Flight Path Planning Site Location: the Grand Mesa in Colorado, Altitude 9.5 kft –SWE is Well Studied in this Region –Ground Truth Has Been Validated via HP Mashall, PhD –TOI Flight Facility Close by in Grand Junction –Flight Altitude: 9 kft Above Site Aircraft - Antenna Considerations –Total Altitude: 20 kft –Velocity: 72 m/s –Altitude: 2.8 km –Swath @ Altitude: 0.5 km Flight Plan Estimates –Raster Type Scan –Area: 15 km x 3 km –Starting Point: Longitude 39º, Latitude -108º, UTM Zone 12 –6 – 7 Lines/Passes –20 Total Lines With Repeat Passes –20 Min per Line (With Turns); 2 Hrs – 2.5 Hrs per Flight Ground Truth Data 15 km 3 km Site 3

4. WISM IIP Airborne Experiments  First Campaign, Jan 2015: Baseline SWE Measurement  Integration and Certification: 4 – 5 Days  Mission and Test Flights: 5 – 6 Days 4 flights, ~3 Hrs Per Flight 12 Hrs Total  Option 1, Oct 2015: Snow Free Measurement  Integration and Certification: 2 – 3 Days  Mission and Test Flights: 5 – 6 Days 4 flights, ~3 Hrs Per Flight 12 Hrs Total  Option 2, April 2016: Peak Snow Measurement  Integration and Certification: 2 – 3 days  Mission and Test Flights: 5 – 6 Days 4 flights, ~3 Hrs Per Flight 12 Hrs Total Twin Otter – DC6 4

5.  Estimated Mounting  Antenna: Fuselage at 45º  Regal Mini-ATM Lidar (Lidar): Nadir Port/Well  WISM Radar-Radiometer (WISM): Close to the Antenna  Boise Radar: Close to the Antenna  Racks: Close to the Radar and Radiometer System Block Diagram and Mounting 5 Boise Radar Lidar

6. Antenna / SAR / Radiometer Details QU 12-JA- 231-C Triplexer Radiometer Ku / X Band SAR RF Rack Ku / X Band SAR Digital Rack Ka Ku X Focal Plane Array X / Ku / Ka CSA INS Radar components assembled into 40” racks attached via vibration dampeners to floor rail system in Twin Otter INS, T/R Box and Radiometer mounted close to antenna to minimized noise and increase inertial mass Complete system runs on 28 Vdc aircraft power with master shut off breakers T/R Box

7. Design Assumptions System will be designed for an airborne environment  Lidar will be mounted in the Wildcad-3 Nadir port for a 0 degree look-down  Reflector Mount Assy must be such that  a 45 degree look-down angle Reflector will aim completely out of the hatch towards earth  will be able to attach to existing seat rails  will fit within the interior dimensions of the cabin Seat Rail locations 50” Tall Hatch Nadir Port Dimeonsinos (36”x23”x13”|15”)

8. Beam View of Reflector in A/craft Hatch Approx. Reflector position in Fuselage Twin Otter Fuselage System will be designed for an airborne environment  Reflector Mount Assy must be such that  a 45 degree look-down angle Reflector will aim completely out of the hatch towards earth  will be able to attach to existing seat rails Rear A/craft Hatch Twin Otter Cabin 45 0 Beam Angle Seat Track Brackets ZfZf T/R Box (24”x18”x10”) INS Beam Radiometer (23”x15”x11”) Triplexer (1.5”x3”x0.5”) Feed Array (2.8”x2.8”x0.25”) Installation Details

9. Approx. Reflector position in Fuselage Twin Otter Fuselage System will be designed for an airborne environment  Reflector Mount Assy must be such that  Triplexer, INS, Radiometer and T/R Box will be located in close proximity Rear A/craft Hatch Seat Track Brackets T/R Box INS Radiometer Triplexer Feed Array Boise St. Radar Installation Details

10. Approx. Reflector position in Fuselage Antenna Assy Details  Triplexer, INS and Radiometer are especially located in close proximity Rear A/craft Hatch Seat Track Brackets INS Radiometer Triplexer Feed Array Installation Details

11.  Antenna and Radome: .34 m Aperture Diameter,.185 m Focal Length  Sheet Array 3 x 3 x 2 inch  Total Mass ~ 30 lbs  Radar Box  24 x 24 x 26 inch  Mass ~ 100 lbs  Radiometer Box  23 x 15 x 11 inch  Mass ~ 50 lbs  Control Racks: x 2 to 3  Standard 20 x 30 x 40 inch  Mass ~ 350 lbs – 450 lbs  Boise State Radar  12 x 12 x 10 inch  Mass ~ 30 lbs  Lidar  21.9 x 13.4 x 9.7 inch  Mass ~ 30 lbs Radar Radiometer 11 Boise St. Radar Lidar WISM Instrument Suite Size and Weight Information

12. F Z X XfXf ZfZf Current Sheet Array Feed 0.34 m dia 0.34 m Offset Reflector Geometry 0.055 m 0.185 m 76.8° 7.3° between bisector and aperture center f/D=0.544 Reflector 12

13. Instrument Mounting and Flight Environment Mission Location: Grand Mesa Colorado, Altitude 9.5 kft – Altitude: 9K feet above the Grand Mesa; Total Altitude 18 kft – 20 kft – Mission season temperature: 230 K – 275 K Instrument Mounting: Side Door of Fuselage – Antenna pointed out of the rear door hatch of the twin otter @ 45º incidence – Radiometer located in the aircraft main fuselage close, < 1 m, to antenna – Lidar Located in Aircraft Nadir Port Twin Otter – DC6 13

14. Nadir Port (36”x23”x13”|15”) Instrument Suite Mounting 14 Twin Otter – DC6 Rear Nadir Port Mini-ATM Lidar in Nadir Well Approx. Position in Fuselage Twin Otter Fuselage Seat Track Brackets T/R Box INS Radiometer Triplexer Feed Array Boise St. Radar Rear Door Hatch