Design Justification File (DJF) — Design Justification

Design Justification File (DJF) — Design Justification#

Field

Value

Document

DJF — Design Justification (design rationale, trade-offs, make-or-buy and feasibility record)

DRD ref

ECSS-E-ST-40C Rev.1 §4.2.4 / §4.2.5 (DJF concept); ECSS-M-ST-10-01C (review/justification concept); design-level summary of Annex F <6>

Container

Design Justification File (DJF) — compliance/drd/

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

CDR

Status

Draft for SRR — skeleton

Per ECSS-E-ST-40C Rev.1 §4.2.4/§4.2.5 the Design Justification File records the result of all significant trade-offs, feasibility analyses and make-or-buy decisions. For sar-processor the anticipated headline trade-offs are listed below; each is recorded here when decided.


<1> Introduction#

TBD (PDR/CDR).

<2> Trade-off register#

ID

Trade-off

Decided at

Record

DJF-01

Azimuth focusing algorithm: range-Doppler vs chirp scaling vs ω-k

PDR

TBD (PDR)

DJF-02

L0 decompression handling (FDBAQ/BAQ decode scope)

PDR

TBD (PDR)

DJF-03

FFT backend / numerical toolchain addition beyond eopf-provided numpy

PDR

TBD (PDR)

DJF-04

L2 ocean products in or out of scope

SRR

TBC (SRR)

DJF-05

Reuse boundary with msi-processor platform machinery (see SRF)

SRR

committed at skeleton: CI, doc toolchain, package layout, driver convention reused

<3> Feasibility and make-or-buy#

TBD (PDR).

<4> Traceability#

Decisions trace into SDD components and SRS constraints (REQ-D-*). TBD (CDR).