Internal Calibration Software Requirements

SAO-USS-RS-00001-A

REQUIREMENT SPECIFICATION

Internal Calibration Software

Requirements

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SAOCOM PROJECT

SAOCOM PROJECT

Title Internal Calibration Software Requirements

Summary Requirements Specification for SAOCOM SAR Internal Calibration Software

Secondary Reference Circulation Level 1 o 2

This document is digitally signed Workflow Summary

State Assignee Action Completed Date

hmartirena

Review

Approved

05/10/2012

jpcuesta

Review

Approved

06/10/2012

mpetruccioli Review

Approved

09/10/2012

jmedina

Approve

Approved

09/10/2012

Changes Record

Issue Date Author PARA Description

A 14/Sep/12 J. Giardini Systems Engineer J.P. Cuesta SAR System Manager Initial Release

Comisión Nacional de Actividades Espaciales (CONAE) from Argentina owns the copyright of this document which is supplied in confidence and which shall not be used for any purpose other than that for which it is supplied and shall be only reproduced, copied or communicated, in whole or in part, for internal use of CONAE, directly or by third parties holding confidentiality agreements with CONAE. Any person other than the authorized holder obtaining possession of this document by finding or otherwise, should send it, together with his name and address, in a sealed envelope to:

INDEX

1 OBJECTIVE ... 4

2 SCOPE ... 4

3 APPLICABLE AND REFERENCE DOCUMENTS ... 4

3.1 APPLICABLE DOCUMENTS ... 4

3.2 REFERENCE DOCUMENTS ... 5

4 DEFINITIONS AND ABBREVIATIONS ... 5

4.1 DEFINITIONS ... 5

4.2 ABBREVIATIONS AND ACRONYMS ... 5

5 INTRODUCTION ... 7

6 INPUT AND OUTPUT PRODUCTS ... 7

7 REQUIREMENTS ... 9 7.1 GENERAL ... 9 7.2 FUNCTIONAL ... 10 7.3 PERFORMANCE ... 11 7.4 SOFTWARE DESIGN ... 11 7.5 SOFTWARE CONFIGURATION... 11

7.6 SOFTWARE TOOL PLATFORM AND RESOURCES ... 11

7.7 SOFTWARE TOOL INTERFACE ... 11

1 OBJECTIVE

The objective of this document is to specify the software requirements for the Internal Calibration tool.

2 SCOPE

This specification is applicable to the SAOCOM mission Ground Segment software.

3 APPLICABLE AND REFERENCE DOCUMENTS

3.1 APPLICABLE DOCUMENTS

ID DOC ID TITLE

[AD 1] SAO-TN-ARE-PL-0003 SAOCOM Acquisition Modes Design [AD 2] SOG-CAL-TN-300-A SAOCOM Internal calibration scheme [AD 3] SAO-SYS-PL-00006-A SAOCOM System Calibration Plan [AD 4] SOR-SRS-DS-00300-A SAR Instrument Design Document

[AD 5] TBW SAR Antenna Requirements Document

[AD 6] TBW SAR Antenna Design Document

[AD 7] TBW SAR Antenna AIT Plan

[AD 8] TBW SAR Antenna V&V Plan

[AD 9] TBW CTR Requirements Document

[AD 10] TBW CTR Design Document

[AD 11] TBW CTR AIT Plan

[AD 12] TBW CTR V&V Plan

[AD 13] TBW PSU Requirements Document

[AD 14] TBW PSU Design Document

[AD 15] TBW PSU AIT Plan

[AD 16] TBW PSU V&V Plan

[AD 17] TBW TRM Requirements Document

[AD 18] TBW TRM Design Document

[AD 19] TBW TRM AIT Plan

[AD 20] TBW TRM V&V Plan

[AD 21] TBW RM Requirements Document

[AD 22] TBW RM Design Document

[AD 23] TBW RM AIT Plan

[AD 24] TBW RM V&V Plan

[AD 25] SAO-PAS-RS 00001-A L2B SAOCOM SAFETY AND PRODUCT ASSURANCE REQS

[AD 26] GS-USS-DSN-IC-00200 User Segment Service ICD For Applications and Processors

[AD 27] GS-USS-DSN-IC-00200 User Segment Service ICD For Applications and Processors

[AD 28] TBW ICAL SYSTEM LEVEL PHILOSOPHY

3.2 REFERENCE DOCUMENTS

No reference documents are specified within this document.

4 DEFINITIONS AND ABBREVIATIONS

4.1 DEFINITIONS

No specific definitions are used within this document.

4.2 ABBREVIATIONS AND ACRONYMS

AIT Acceptance, Integration and Test AIV Acceptance, Integration and Validation

AM Antenna Model

ANT Antenna

API Application Program Interface ARCH Archive and database subsystem CAL Calibration

CDR Critical design review CE Central electronics CGSS Conae GS services

CODS Conae orbit dynamic services CTR Reception and Transmission Unit DEM Digital elevation model

ECSS European Cooperation on Space Standardization EDSM External data sources management system EM Engineering Model

FTP File transfer protocol

GB Gigabyte

GPPU Generic product processing unit

GS Ground Segment

HH Horizontal-Horizontal HV Horizontal-Vertical ICAL Internal Calibration

ICALSW Internal Calibration software tool ISLR Integrated Side Lobe Ratio

L0 Level zero

L1 Level one

ORR Operations Readiness review OS Operating system

PCC Pulse coded calibration PDR Preliminary design review PFM Proto-Flight Model

PM Production management subsystem PSLR Peak Side Lobe Ratio

PSU Power Supply Unit QR Qualification review RAM Random access memory RF Radiofrequency

RM Radiating Module

SAR Synthetic Aperture Radar SARS

TBC To be confirmed TBW To be written

TRM Transmission and Reception Module VAL Validation

VH Vertical-Horizontal VV Vertical-Vertical

5 INTRODUCTION

This introductory notice is not part of the requirement and is only provided as background information. Internal calibration software (ICALSW) is a tool that allows SAR System (SARS) calibration. From the functional point of view, the SARS is composed of a flying SAR sensor, which is equipped with an on board calibration system and a ground processing station generating calibrated images. On ground, the images are produced and calibrated based on the downstream data obtained via the downlink channel. These information includes both SAR echo signals and calibration signals. The software tool specified within this document is responsible for extracting the calibration data from the stream, and producing a set of calibration constants, a process aided by telemetry information.

6 INPUT AND OUTPUT PRODUCTS

As shown in Figure 1 the internal calibration processor products are the sensor calibration

constants for the central electronics and antenna phased array, and also chirp replicas for the CE. All of them are obtained by the calibration processor by using the products of the L0 Formatter and the antenna model, together with the information provided by the configuration file which defines processing options and also contains sensor pre-flight characterization data. Calibration at multiple points in the dynamic range may also require access to the ARCH database (CUSS Archive and Database Subsystem).

Table 1. Input and output elements and their relationship with sources and consumers.

Product Type Source Consumer

CE Calibration

Constants Output product - Antenna Model Software

Antenna Calibration

Constants

Output product - Antenna Model Software

On board

calibration data Input product L0 Formatter -

On board

calibration routine Input product L0 Formatter -

Sensor Telemetry Input product L0 Formatter -

Antenna Feed Input API Antenna Model -

Pre-Launch

Characterization Input product internal database - Processing

configuration Input product internal database -

Threshold

CUSS - Partial

PM (Production Manager Subsystem)

Precision orbit & attitude

ARCH (Archive and

Database Subsystem)

L0 Annotated formatter

Antenna model software

SAR W-K processor CODS Annotated L0 Product Antenna pattern Calibration Constants Chirp replica Precision orbit & attitude Calibrated L1 product Conf. File

GPPUGPPUGPPUGPPU Generic Product Processing Unit (GPPU) CGSS CCSDS virtual channels SAR raw data (CCSDS Virtual Channels) EDSM

(External Data Sources Managment Subsystem) References ARCH-based products transfer CUSS interface with processors XPNet FTP-based transfer xxx product PU CUSS Product Data processor ParameterFile.xml ReturnFile.xml ANT Phase & Gain Matrix CE Chirp Replica CE Phase & Gain Conf. File Conf. File Internal calibration processor Conf. File CAL/VAL DEM store StatusFile.xml LogFile.xml Calibration constants

7 REQUIREMENTS

7.1 GENERAL

Requirement: ICALSW shall be implemented as a software tool.

Requirement 7.1-1. Supported activities ICALSW shall:

- support the instrument on-ground AIT/AIV activities - support the instrument in-orbit calibration

- support the SAOCOM GS development activities

- support the performance assessment analysis of the SAR instrument, flight segment and system mission

Requirement 7.1-2. Integration

ICALSW shall be integrated to:- SAOCOM GS - SAOCOM SAR Instrument Simulator

- SAOCOM Flight Segment Simulator - SAOCOM System Mission Simulator.

Requirement 7.1-3. On-ground activities ICALSW on-ground activities shall include:

- Fitting, verification and validation of the ICALSW for in-flight operation against actual measurements results at SAR CE, SAR antenna and SAR instrument level.

Requirement 7.1-4: In-flight activities

The ICALSW in-flight activities shall include:

- Use of internal calibration modes for actual phased array antenna RF paths gain and phase drift measurement

- Estimation of phased array antenna elements excitation drift (in order to produce Antenna phase and gain drift matrix up to the TRMs, without including Radiant Modules since they are not included in Internal Cal. paths, and using the Antenna Model Software API to retrieve and compensate for antenna calibration network components behavior)

- Measurement of CE phase and gain drifts

- Generation of the CE chirp replica based on internal calibration modes (to which the Antenna model software shall later apply the antenna transference function to obtain the system replica) based in chirp reconstruction models . INFORMATION: Chirp reconstruction models are specified in [AD 29].

- Update of the software if major differences between estimated values and possible values to obtain in-flight antenna measured patterns are detected

Requirement 7.1-5: Agreement to SAOCOM SAR ICAL System Level Philosophy ICALSW results shall be in agreement with [AD 28] so that ICAL system level accuracy requirements are obtained.

7.2 FUNCTIONAL

Requirement 7.2-1.

ICALSW shall produce a set of system internal calibration constants used to correct the sensor state at the time of acquisition.

Requirement 7.2-2.

ICALSW shall use pre-launch characterization data to produce the calibration constants. Requirement 7.2-3.

ICALSW shall use on board calibration data generated by the on-board calibration system to produce the calibration constants.

Requirement 7.2-4.

ICALSW shall use sensor telemetry data to produce and / or validate the calibration constants. Requirement 7.2-5.

ICALSW shall use Antenna Model data through the AM provided API to produce the calibration constants.

Requirement 7.2-6.

ICALSW shall use predefined and yet configurable processing algorithms to produce the calibration constants.

Requirement 7.2-7.

ICALSW shall use sensor configuration data representing the system at the time of acquisition to produce the calibration constants.

Requirement 7.2-8.

ICALSW shall use on-board calibration routine to produce the calibration constants. Requirement 7.2-9.

ICALSW shall implement PCC of different lengths

Requirement 7.2-10.

ICALSW shall estimate CE gain and phase calibration constants for each polarimetric channel Requirement 7.2-11.

ICALSW shall estimate TRM internal calibration constants for each polarimetric channel Requirement 7.2-14.

ICALSW shall estimate antenna RF paths internal calibration constants for each polarimetric channel

Requirement 7.2-12.

ICALSW shall be able of providing nominal outputs based only on partial information. Requirement 7.2-13.

ICALSW tool shall provide a log for execution flow tracking including unique identifiers such as execution date and time.

Requirement 7.2-14.

ICALSW log file maximum size shall be configurable and controlled by ICALSW.

7.3 PERFORMANCE

Requirement 7.3-5: Agreement to SAOCOM SAR ICAL System Level Accuracy

ICALSW results shall be in agreement with [AD 28] so that ICAL system level accuracy requirements are obtained.

Requirement 7.3-1. Execution time

ICALSW execution time to deliver the required antenna patterns for calibrating any SAOCOM acquisition mode product shall be less than 10 minutes.

7.4 SOFTWARE DESIGN

ICALSW software tool shall be developed using open source libraries. Requirement 7.4-2. Modularity and maintainability

ICALSW software architecture shall be modular to allow progressive development and maintainability.

7.5 SOFTWARE CONFIGURATION

Requirement 7.5-1. ICALSW parameters shall be configurable to permit modification of any input data, procedure and thresholds.

Requirement: each instrument ICAL acquisition mode shall be fully supported by the ICALSW.

7.6 SOFTWARE TOOL PLATFORM AND RESOURCES

ICALSW tool shall be able to run on Intel x-86 32bit and 64bit based platforms with one or more microprocessor cores.

Requirement 7.6-2. RAM

ICALSW shall need no more than 4GB of memory. Requirement 7.6-3. Operative system

ICALSW OS target shall be Ubuntu Linux LTS (version >10).

7.7 SOFTWARE TOOL INTERFACE

Requirement 7.7-1. ICALSW software shall provide means to be included in SAOCOM automatic image processing chain without requiring operators.

Requirement 7.7-2. ICALSW software shall be delivered with three execution interfaces:

1. A linux command line set of executable for integration to the automatic image processing chain. 2. A graphic user interface for model parameters configuration and outputs visualization

3. A library with a clearly defined API to be embedded in other calibration/validation, diagnostic and simulation front-end tools in order to get access to in-flight measurements, pre-launch

characterization data, sensor configuration, sensor temperatures components.

Requirement 7.7-3. All ICALSW software interfaces shall be able to accept the inputs and provide the outputs defined in the functionality requirements segment.

Requirement 7.7-4. I/O Products Structure

ICALSW software input and output products shall be defined based on XML format and agreed with the corresponding users and providers, ensuring compatibility to GS according to GS-USS-DSN-AN-00100 (CUSS Products General Structure) .

Requirement 7.7-5. Command line executable control interfaces

ICALSW software control interfaces used for command line execution shall be defined based on XML format, ensuring compatibility to GS and according to GS-USS-DSN-IC-00200 (User Segment Service ICD For Applications and Processors).

Requirement 7.7-6. All configuration parameters used shall be stored in XML files and date/time tagged for model configuration traceability and repeatability.

Requirement 7.7-6. Input and output products in production chain

ICALSW working as an unattended executable in the processing chain shall support input and output products and their relationship with source and consumer processors described in the Table 1.

Requirement 7.7-6. Configuration file

ICALSW configuration file (according to CUSS ICD for processors and applications) shall include as a minimum all the processing parameters, pre-Launch characterization ICALSW internal DB pointers, threshold values.

Processing parameters shall include the selection of antenna phase and gain matrix product data level (at int. cal. RF path level, TRM level, antenna RF Tx or Rx level, etc).

Requirement 7.7-6. Simulators interface

The ICALSW API will be used as interface for Mission, Satellite and Instrument simulators.

7.8 SOFTWARE TOOL DOCUMENTATION

The software documentation to be delivered shall be in accordance with the applicable standard ECSS-E-40.

Requirement 7.8-2. Programming language

For individual processors, the software shall be written in a single language to be chosen by the Contractor and agreed with the Agency.