{"artifact_id":"L1-100","layer":"L1","title":"Synthetic Aperture Radar (SAR) — range-Doppler coherent imaging","domain":"Remote Sensing","sub_domain":"Microwave coherent imaging","physics_fingerprint":{"L_DAG":4.0,"title":"Synthetic Aperture Radar (SAR) — range-Doppler coherent imaging","domain":"Remote Sensing","carrier":"radio_wave","primitives":["L.emit.chirp","S.scan.platform","L.pulse_compression","L.range_doppler","int.spatial"],"sub_domain":"Microwave coherent imaging","noise_model":"speckle","problem_class":"nonlinear_inverse","solution_space":"2D_complex_scattering","difficulty_delta":5,"integration_axis":"angular","sensing_mechanism":"sar_coherent_imaging"},"observable_profile":{"metric":"PSNR_dB","regime":"Existence of the recovered 2D complex scattering is guaranteed within the declared Omega bounds. Uniqueness is local rather than global (non-convex landscape); convergence depends on initialisation and priors. Stability is moderately conditioned (kappa_eff ~= 20); platform_motion_error dominates the stability cliff; ionospheric_phase and the remaining mismatch parameters contribute higher-order bias terms. Multiplicative speckle (rayleigh amplitude / exponential intensity) sets the irreducible data-fidelity floor, while TV / wavelet-sparsity / deep priors stabilise recovery at the ill-conditioned end of Omega.","secondary":"SSIM"},"size_tiers":{"center_spec":{"omega":{"H":8192,"W":8192,"SNR_dB":15.0,"pixel_m":3.0,"N_pulses":2048,"lambda_cm":5.6,"ionospheric_phase":0.0,"platform_motion_error":0.0,"speckle_coherence_loss":0.0},"input_format":"measurement_only","problem_class":"sar_range_doppler","forward_operator":"sar_range_doppler_forward","epsilon_fn_center":"18.0"},"omega_bounds":{"H":[1024,32768],"W":[1024,32768],"SNR_dB":[0.0,30.0],"pixel_m":[0.3,30],"N_pulses":[256,16384],"lambda_cm":[0.5,30],"layover_shadow":[0.0,0.3],"ionospheric_phase":[0.0,2.0],"platform_motion_error":[0.0,1.0],"speckle_coherence_loss":[0.0,0.5]},"epsilon_bounds":{"psnr_db":[5.0,40.0]},"allowed_problem_classes":["sar_range_doppler"],"allowed_omega_dimensions":["H","W","pixel_m","lambda_cm","N_pulses","platform_motion_error","ionospheric_phase","speckle_coherence_loss","SNR_dB","platform_motion_error","ionospheric_phase","speckle_coherence_loss","layover_shadow"],"allowed_forward_operators":["sar_range_doppler_forward"]},"hardness_fn":{"type":"epsilon_fn","delta":5,"kappa":400,"metric":"PSNR_dB"},"initiator_dataset":[{"name":"primary","weight":1.0,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":0.0,"chain_hash":"0x59a24287101a429839669a5b318a683ffd8aaf242c7128db57f8c0bf18118353","chain_tx_hash":"0xffd9dd8d05128c88c52d826e619483f4783881ab8ce004299ff20012cc655259","chain_block":41554185}