Characterization, Calibration and Validation: An INTA Approach

Characterization, Calibration and Validation: An INTA Approach Nuria Casal Vázquez, Javier del Castillo Mena, Patricia Cifuentes Revenga, Juan Manuel Cuerda Muñóz, Marcos García Rodríguez, Nuria Gimeno Martínez, Beatriz Gómez Miguel, María José González Bonilla, Juan Ramón Larrañaga Sududpe, Adolfo López Pescador, Laura Ojalvo Sánchez gomezb@inta.es 27/09/2013 Pag.: 1

Contents Introduction: CALVAL Centre General Approach On Ground tasks Antenna Instrument Performance assessment SAR E2E Configuration On Ground Tests Basic Product Definition In Flight tasks Summary 27/09/2013 Pag.: 2

Introduction: Governmental mission part of PNOTS (Spanish Program for Earth Observation) Intended to support Spanish needs Dual System: Commercial / scientific SAR system Security and defence / civil users Attitude and Orbit Parameters Nominal height at equator: Orbits per day Nominal radar duty cycle System Parameters Incidence angle range for Stripmap/ ScanSAR / Spotlight Antenna length Nominal antenna look direction Antenna width Number of Stripmap/ScanSAR/SpotLight elevation beams Number of spotlight azimuth beams Polarization PRF Range Bandwidth Radar carrier frequency Radiated RF power Inclination LTAN Total zero Doppler steering 514 km 15 + 2/11 13% - 18% 20º-45º (full performance) 15º-60º (accessible) 4.7 m right 0.7 m up to 256 up to 256 H/V Single, Dual 2200-6500 Hz 100/150/300 MHz 9.65 GHz 2 KW 97.4º 18:00 ± 0.25 h (local time) Yes Main Applications: Security/defence, marine, land use, hydrology, pollution, natural hazards, science, etc 27/09/2013 Pag.: 3

Introduction: CALVAL Centre PAZ SPACE SEGMENT PAZ SATELLITE PGS S Band TC/TM X Band TM PDGS Payload Data Ground Segment FOS Flight Operation Segment G/S Ground Station ARF Acquisition & Routing Facility M&C Monitoring & Control SMC Secure Management Centre 27/09/2013 FOCC Flight Operations Control Centre IO Instrument Operation MPF Mission Planning Facility MCS Mission Control System FDS Flight Dynamics System SSIM Spacecraft Simulator DT Orders PDS Payload Data System CalVal Centre Calibration &Validation Mission Plan PSP PAZ SAR Processor OP Operation Package TM Decrypter C&CP Characterization and Calibration Package MAC Mission Archive and Catalogue V&MP Verification and Monitoring Package DT Files Science Package MUS Master User Services Request PAZ Product delivery PM Perform Monitoring SAR system operation Commanding Configuration Processing SAR system performance Characterization Calibration Performance analysis SAR system verification Operation monitoring Quality limits checks PAZ Mission Pag.: 4

General Approach PAZ SAR System: TSX + New Frontend CN facility Individual TRM characterization Antenna System configuration / Commanding / Processing External inputs HDS provides: CN element characterization, antenna measurements Base for commanding processing provided by DLR Pre launch Launch In-flight Antenna Instrument E2E System Configuration Performance Assessment Product Definition Pre-imaging tests First Validation Characterization/Calibration Second Validation Instrument measurements Instrument tests CP Plan / Procedures Support (SW tools and Cal elements) Space Segment Specific Tasks Instrument tests 27/09/2013 Pag.: 5

On Ground Tasks Ant Patterns Antenna Instrument PAZ config update Int Cal Proc, HK Inst Model = f (temp, BW, TRM duty cycle, ) Nom Op limits Ant Patterns Perf Assess Monitoring IRF, Inst stability Antenna Instrument: Internal Calibration Processes CN Signal Analysis Performance Assessment SAR E2E configuration On Ground Test Basic Product Definition Signal statistics, T Ant Model Validation Validation-0 Product Def Ambiguities, NESZ, IRF, Inst stability Contributions to: IRF Stability NESZ Radiometry 27/09/2013 Pag.: 6

On Ground Tasks: Antenna (I) On-ground Antenna Raw measurements Data Analysis Embedded SubArrays patterns Antenna Geometry Derive Other characterisation data needed: (Antenna Polarization crosstalk, Antenna beamwidth, SAs losses) Antenna Model Input Files Generation/configuration Antenna model configuration Excitation coefficients Excitation errors AM On-Ground Validation Antenna model patterns comparison to Ground measured test dataset One EQM panel validation campaign Three FM leaves validation campaign Establish Antenna Model accuracy amplitude deviation db Full BW and TX/Rx reciprocity check 1.2 Tx amplitude deviation db 1 0.8 Rx amplitude deviation 0.6 0.4 0.2 0 0 5 10 15 20 25 30 35-0.2-0.4-0.6-0.8-1 TRM phase deviation (º) 10 5 0 0 5 10 15 20 25 30 35-5 -10 Tx phase deviation degrees Rx phase deviation degrees -15 TRM Strip 015 2way VV Shape LEAF Accuracy C validation Strip 01 Bore 05 10 15 26 HH(dB) 0.43 0.19 0.16 0.07 0.23 0.26 VV(dB) 0.28 0.15 0.16 0.05 0.05 * RESULTS FOR:strip_015V_Polarization * 0.11 * AMT Beam Gain shape Accuracy max error (db): 0.19 Strip * AMT Gain error (db): -0.21 * 01 AMT p2p Gain 05 error 10 (db): -0.18 15 26 HH(dB) -0.04-0.09-0.01 +0.05 +0.6 VV(dB) -0.76-0.27 +0.04-0.17-0.64 27/09/2013 Pag.: 7

On Ground Tasks: Antenna (II) First PAZ Configuration Antenna Pattern Generation. Coefficients synthesis to match system beam definition. Reference patterns generation. Do not include TRM reference errors. Not received from Space segment yet. Experimental Antenna model 3D Subarray radiation pattern. Both Co-polar and crosspolar pattern calculation. Easy Antenna Errors simulation (TRM setting, Antenna geometric distortion) Used to analyse Antenna error budget and effect on performance degradation. NESZ(dB) -10-12 -14-16 -18-20 -22-24 -26 system sensitivity-nesz 14 12 10 8 6 4 2 beam Strip-005 NESZ variation 0-28 -21.05-21 -20.95-20.9-20.85-20.8-20.75-20.7-20.65 10 15 20 25 30 35 40 45 50 55 NESZ-dB look angle 27/09/2013 Pag.: 8

On Ground Tasks: Instrument (I) RF design CN facility Performance assessment Budget error Signal Paths Engineering Design Temp sensors HW characterization Operation modes Data processing Commanding-processing customization for PAZ Monitoring definition Instrument stability and uncertainty estimation Internal calibration processes Signal Analysis 27/09/2013 Pag.: 9

On Ground Tasks: Instrument (II) Internal Calibration Processes Element Characterization (Amp & ph = f (freq, temp, )) Temp in oper assessment PAZ housekeeping Replica reconstruction Raw data pre processing Path signal (Imaging, TxCal, RxCal, CE Cal) Base of operation/commanding Inst effects model simulation Error estimation Int Cal Processes Design Other points Prelim PAZ Config Signal analysis Test Desgin (DT, process,analysis) Customization Perf Assessment E2E Config Key points: Instrument stability Internal Calibration Processes HK temp and stability monitoring Validation Error assessment after internal calibration Calibration processes 27/09/2013 Pag.: 10

On Ground Tasks: Instrument (III) Internal Calibration Processes Simulation of effects TRM duty cycle effect model CN effect on replica Based on DT data analysis (PSP by default) IQ correction Replica reconstruction Drift correction Based on DT data analysis (PSP customization) Effects of CN on replica reconstruction TRM duty cycle effect correction 27/09/2013 Pag.: 11

On Ground Tasks: Instrument (IV) Signal analysis TRM temperature compensation mode Base of operation/commanding Other points Prelim PAZ Config Test Data Takes CN Characterization PAZ housekeeping Signal parameter limit thresholds Rx Gain for Cal signals CN facility signal analysis Signal parameters Error estimation Test Design Customization Perf Assessment E2E Config Key points: Instrument stability Limits monitoring IRF product performances Validation Instrument stability IRF performances Calibration strategy 27/09/2013 Pag.: 12

On Ground Tasks: Instrument (V) Signal analysis Signal Parameter Derived parameters Limits and performances Noise Power IQ parameters SNR Noise figure IQ param limits Tx Cal Rx Cal CE Cal Replica IQ parameters Overflow Dynamic range Energy start end spectrogram SNR Internal delay Length Frequency components IRF: maximum (amplitude, phase and position), resolution, ISLR PSLR Amplitude and phase Drift Limits for monitoring IRF degradation Instrument stability Product definition: performances Individual TRM characterization TRM deviations, TRM failures TRM reference Limits for Antenna beam required optimization 27/09/2013 Pag.: 13

On Ground Tasks: Instrument (VI) Signal analysis TX Cal pulses analysis example Stripmap Data Take executed with PAZ complete Front end assembled Instrument Drift 27/09/2013 Pag.: 14

On Ground Tasks: Performance Assessment (I) PAZ Config 0 Path signal characterization Internal calibration processes (with estimated HK) Antenna pattern measurements Antenna model Main sources: Antenna patterns Cal signal analysis Beam mode operation First Performance Assessment Ambiguities NESZ On Ground Tests Radiometry Cal signal conditioning IRF Rx Gain definition Cal signal analysis Parameters Internal calibration processes Resolution, pixel location, PSLR, ISLR Command strategy validation RAR, AAR, DTAR, swath width PAZ Config 1..N Second Performance Assessment NESZ Radiometric stability Relative radiometric accuracy Absolute radiometric accuracy IRF Radiometry 27/09/2013 Pag.: 15

On Ground Tasks: Performance Assessment (II) Ambiguity Assessment Performance Assessment and Validation Tool 27/09/2013 Pag.: 16

On Ground Tasks: SAR E2E Configuration (I) PAZ SAR System Space Segment is simple and flexible and requires to be configured by onboard tables and commanded state by state from ground. Ground Segment shall manage the E2E system configuration: Generation of system configurations and control the coherence Monitor the behaviour of the configured system Update of the configuration Default configuration Antenna patterns Coherence On board configuration Inst Charact Performance analysis Commanding configuration Processing configuration Int Cal Process Operation Verification System Tests Configuration Update 27/09/2013 Pag.: 17

On Ground Tasks: SAR E2E Configuration (II) [Manually] System Table Generation SystemTable Reference Orbit Inputs for Row, Panel, Module Leaf Leaf Levels AdditionalElevBeams AdditionalAzBeams Additional PRF Values Elevation Beam Constraints PRF Values Specification Operation Modes Definition: beams, angles, ovelaps Total Zero Doppler Steering Calculation Initial Beam Specification PN Gating Codes Generation PRFConfigTbl AttSteeringTbl PNGatingCodes BeamSpecTbl Antenna Requirement Performance Analysis: PRF selection, NESZ, required Two Way Gain Make SARProductInfo coherent with Elevation Beams Custom TX Pulse Definition CustomTXPulse [add_undefined_beams.m] (BST): Adds calbeam, notch, boresight and undefinded beams Set Beam Performance Requirement [set_fullperformanceflag_in_bst.m] BeamSpecTbl (ST): Check SARProductInfo coherent with Elevation Beams. Update RPGDataAcquisition [update_onboardbeammapping.m] Update Onboard Mapping (ST) keeping coherence with BST SystemTable SystemTable Azimuth Modes + Antenna Pattern Mask Generation Set Absolute Calibration Factor per antenna mode, imaging mode, beam, look direction and polarization Calculate Swath width and Azimuth Coverage per Imaging Mode, Beam, Polarization and Tx BW BeamSpecTbl AbsCalFactor SwathPreview 27/09/2013 Pag.: 18

On Ground Tasks: SAR E2E Configuration (III) 27/09/2013 Pag.: 19

On Ground Tasks: On Ground Tests (I) Considered flows: Production flows System configuration update flows Calibration User flows INTA Proposed SVTs High level objectives: Operation V&V Configuration V&V Measurements V&V On ground E2E Validation In flight pre-planning support 1.- Flow checking Operation and measurement capabilities 3.- Preliminary acceptance Configuration update capabilities SAR Requirement Validation In-flight demonstration 2.- On-ground characterization-calibration Performance assessment Final operation and configuration flows definition Characterization-calibration for monitoring and processing 27/09/2013 Pag.: 20

On Ground Tasks: On Ground Tests (II) Flow checking SVT 1 Configuration Update Operation (Production & Calibration) Nominal modes (all) beams (near far) Non imaging modes (PN Gating, noise, ) Experimental and Calibration modes Calibration strategies TRM temp compensation Calibration pulses structure Radar Parameters (BW, PRF, RxGain, first point delay,..) House Keeping Events Measurements & processes SVT 1DTs Summary Mode DT SM-S 6 SM-D 9 SL-S 4 SL-D 3 HR-S 4 HR-D 1 SC-S 3 Health Check 6 Cal & Noise 5 DRA 2 Characterization, Calibration, Validation tasks Cal modes TOTAL 9 52 27/09/2013 Pag.: 21

On Ground Tasks: Basic Product Definition TerraSAR-X inheritance & coordinated operation Beam-Mode Tree SM-S, SM-D SL-S, SL-D HR-S, HS-D SC Product Tree L1b Product data structure and annotations Performance parameter definition Beam - mode definition for PAZ Data structure provided by PSP and PDS Pre - launch performance parameters assessment 27/09/2013 Pag.: 22

In-flight Tasks (I) INTA Characterization, calibration, validation Plan Processes Calibration sites and targets Campaigns design Test design Steps in the plan: Tests on positioning and attitude capabilities, system timing, antenna pointing, and internal calibration. 1st System Validation phase will provide a first PAZ performance analysis. Main characterization/calibration stage 2nd System Validation where actual PAZ performance will be established and updated basic product definition shall be delivered. PAZ SAR system Acceptance 27/09/2013 Pag.: 23

In-flight Tasks (II): Processes Geometric Calibration Processes Instrument delay Propagation Delay CR, transponders location Data Takes (commanded delay, images, TZD LUT, ) Doppler estimation error CALIX CALIX Location Location Characterization Characterization & CALVAL CALVAL CR Locations in images (range & azimuth) Instrument Processes Instrument Drifts Calibration network on ICAL ICAL (Amp & Phase) ground measurements Replica CR location PT analysis Data Takes (CAL CALIX sequences, images, ) CALIX Instrument Instrument Drifts Drifts Characterization Characterization & CALVAL CALVAL Beam def (Pattern & Coefficients) Data Takes AMT (Rain Forest,reflectors, AMT TRM TRM Antenna patterns Health check, ) monitoring monitoring Excitation Coeff Images Performance Performance Assessment Assessment and and Validation Validation AMT Val and Beam Optimization Processes FD FD Antenna Antenna Attitude Attitude AMT AMT Pointing Pointing Characterization Characterization and and CALVAL CALVAL Calibration sites: rain forest Reflectors location ( range incidence angles) Relative CALIX Relative and and absolute absolute radiometry radiometry Receivers CALIX Characterization Characterization and and CALVAL CALVAL Data takes (nominal, notch, squint,) images Radiometric Calibration Processes 27/09/2013 Pag.: 24

In-flight Tasks (III): Calibration sites and targets Simulated test sites: Barrax and Los Monegros test site INTA-Torrejón A/D pass far and near range beams Other possible target locations at INTA facilities RIX sensor. 2012. Barrax Simulated test sites close to INTA: combined beams 4 and 12 & INTA facilities 27/09/2013 INTA s SAR sensor (07/07/2011) PAZ Mission Pag.: 25

In-flight Tasks (IV) Campaign Design Test Sites Definition Satellite coverage Point site opportunity analysis over an orbit cycle (11 days ) Test sites: beam, mode, location and timming Calibration targets Mega test sites definition Calibration targets management: from ground location to External Calibration CALIX SAR Ext Cal Perf assess and val tool Interf signature tool Pol signature tool 27/09/2013 Pag.: 26

In-flight Tasks (V): Test Design Test Design: DT commanding Support Inputs Test Sites Definitions Operation Modes Outputs Command Set and Planning Information Design Validation Radar Parameter Editor Command Editor 27/09/2013 Pag.: 27

In-flight Tasks (VI): Test Design Work Environment and Data Processing PSP INVOCATION: ORDER FILE PAZ SAR PROCESSOR DATA/PARAMETERS FROM CAMPAING AND TEST DESIGN: Datatake File ID Imaging Mode Polarization Mode Location or Timing Auxiliary Product DATA FROM SATELLITE: Instrument Source Packets Orbit and Attitude Files HouseKeeping INPUTS ATTITUDE FILE ORBIT FILE LOGICAL DATATAKE AUXILIARY PRODUCT HOUSE KEEPING PARAMETERS: TEST CASE DATE UNIQUEDATATAKE DATATAKE FILE ID LEVEL OF PROCESSING LEVEL 0 BASE PROCESSING LEVEL 0 SAR PROCESSING LEVEL1B PROCESSING NRT PROCESSING OUPUTS: PRODUCTS L0 PRODUCT BASE COMPONENTS SAR COMPONENTS L1B PRODUCT: SSC MGD (SE/RE) GEC (SE/RE) EEC (SE/RE) 27/09/2013 Pag.: 28

In-flight Tasks (VII): Performance analysis Distributed Area Analysis Performance Assessment and Validation Tool DLR/TSX DATA 27/09/2013 Pag.: 29

Summary PAZ SAR System deeply related to TerraSAR-X mission (DLR support) Modes SAR engineering Products INTA is implementing a characterization, validation and calibration plan On ground tasks: focused on internal calibration and antenna model Objectives to be ready at launch (tools, support, plans-procedures): Internal calibration processes Monitoring requirements PAZ E2E configuration Preliminary product definition CP characterization, calibration and validation plan In flight tasks (under design) Scientific / Experimental part of is not included here 27/09/2013 Pag.: 30

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