Software Requirements Specification (SRS)#

Field	Value
Document	SRS — Software Requirements Specification
DRD ref	ECSS-E-ST-40C Rev.1, Annex D
Container	Technical Specification (TS) — `compliance/drd/` (source), published subset in `docs/`
Project	`sar-processor` (gitlab.eopf.copernicus.eu/ipf/sar-processor)
Software criticality	Category C (ECSS-Q-ST-80C Rev.2 / ECSS-E-ST-40C Annex R)
Baselined at	PDR (Preliminary Design Review)
Status	Draft for SRR — skeleton

This SRS is a major constituent of the Technical Specification of sar-processor. It decomposes the system requirements (SYS-*, SSS) and the interface requirements (REQ-IF-*, IRD) into uniquely identified software requirements (REQ-*), each bound to a verification method (T Test / A Analysis / I Inspection / R Review of design). The processing-algorithm mathematical basis is not (re)specified here: it is the subject of the DPM and ATBD. The footprint is tailored to a Category C, single-developer ground-segment processor. Requirements content is TBD (PDR).

<1> Introduction#

Purpose. Specify the software requirements for sar-processor, a generic spaceborne SAR ground-segment forward processor that transforms downlinked raw Level-0 SAR instrument source packets into focused L1 SLC and detected/projected L1 GRD products (L2 ocean TBC). TBD (PDR).

Objective. Parent specification for the design (SDD) and the V&V activities (V&V Plan). Every REQ-* traces upward to SYS-* and/or REQ-IF-*, and downward to a verification method (clause <6>) and, at CDR, to a design element and a test case (traceability matrix).

<2> Applicable and reference documents#

Per SDP <2>. TBD (PDR).

<3> Terms, definitions and abbreviated terms#

See SSS <3>. TBD (PDR).

<4> Software overview#

<4.1> Function. Sensor-agnostic SAR forward chain driven by a per-sensor profile (first profile: C-band, Sentinel-1 C-SAR reference data). <4.2> Environment. EOPF CPM (eopf == 2.8.1), Python 3.11, Zarr outputs. <4.3> Relations. Sibling of ipf/msi-processor (platform reuse, SRF); shared ipf/data-store. TBD (PDR).

<5> Requirements#

ID scheme (mirrors msi-processor):

REQ-F-<STAGE>-NN — functional, per processing stage (stage set fixed at PDR from the ATBD chain: L0 decode, Doppler-centroid estimation, range compression, azimuth focusing, radiometric calibration, multilook/detection, geocoding);
REQ-P-* performance, REQ-D-* design & implementation constraints, REQ-AD-* adaptation data (per-sensor profile / ADFs), REQ-S-* security, REQ-DAT-* data/product requirements.

All TBD (PDR — pending SentiWiki S1 ingest).

ID	Requirement	Trace	Ver.
REQ-F-TBD-01	`TBD (PDR)`	SYS-TBD	—

<6> Validation approach#

Per requirement group; delegated to the V&V Plan. TBD (PDR).

<7> Traceability#

SYS-*/REQ-IF-* → REQ-* in compliance/traceability/traceability-matrix.md. TBD (PDR).

<8> Logical model#

Top-level logical model of the forward chain (mermaid diagram). TBD (PDR).