# 📐 L2 Spec — Inverse Synthetic Aperture Radar (ISAR) — rotating-target imaging Mismatch-Only Spec
**ID:** `L2-252-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-252`](/artifact/l1/L1-252)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41554002
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| Prf hz | Hz | 10 – 100000 |
| Snr db | dB | -10 – 40 |
| N pulses | — | 32 – 4096 |
| Phase error | — | 0.0 – 0.2 |
| N range bins | — | 64 – 4096 |
| Motion error | — | 0.0 – 0.3 |
| Cross range aberration | — | 0.0 – 0.3 |
| Doppler ambiguity error | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
15.0 + 0.25*SNR_dB - 10.0*motion_error - 15.0*phase_error - 8.0*doppler_ambiguity_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`d7643afd9f69dc2ff4339acd52a77b0c7625dc8d7977f19303bd0d732d071cf1`
## 5. On-chain Registration
- **Chain hash:** `0xda0739dc6a4fbac596070e83e5f07c0508c0ecf13c259b00f8adf551ab1d6180`
- **Chain tx hash:** `0x07adbc73427f8d12295690afe03c351e5177d9630f604777ea0e22a399126d5a`
- **Chain block:** `41554002`
---
## File Mapping
This bundle consists of: `L2-252-001.md`, `L2-252-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-252-001.md` | Source of truth — edit this | Human or LLM |
| `L2-252-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-252-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._