{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:W23HSGIJ5AOTGHQXMCYZKMP2RM","short_pith_number":"pith:W23HSGIJ","canonical_record":{"source":{"id":"1905.00963","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"eess.SP","submitted_at":"2019-05-01T12:42:25Z","cross_cats_sorted":[],"title_canon_sha256":"db1920de177b77c8e2aa6a5708302a1fc6dd07df85d46de087ad2afe37111667","abstract_canon_sha256":"153c8fce7f3a2068ed76ccbc4984cf229d38cf23777c0b2ffb380b6b0a7344a3"},"schema_version":"1.0"},"canonical_sha256":"b6b6791909e81d331e1760b19531fa8b268b9f9330dac1f6871de844b379926c","source":{"kind":"arxiv","id":"1905.00963","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1905.00963","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"arxiv_version","alias_value":"1905.00963v1","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1905.00963","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"pith_short_12","alias_value":"W23HSGIJ5AOT","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_16","alias_value":"W23HSGIJ5AOTGHQX","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_8","alias_value":"W23HSGIJ","created_at":"2026-05-18T12:33:30Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:W23HSGIJ5AOTGHQXMCYZKMP2RM","target":"record","payload":{"canonical_record":{"source":{"id":"1905.00963","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"eess.SP","submitted_at":"2019-05-01T12:42:25Z","cross_cats_sorted":[],"title_canon_sha256":"db1920de177b77c8e2aa6a5708302a1fc6dd07df85d46de087ad2afe37111667","abstract_canon_sha256":"153c8fce7f3a2068ed76ccbc4984cf229d38cf23777c0b2ffb380b6b0a7344a3"},"schema_version":"1.0"},"canonical_sha256":"b6b6791909e81d331e1760b19531fa8b268b9f9330dac1f6871de844b379926c","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:47:08.118573Z","signature_b64":"5a/odZmq3qKAGAHkrCF0HKCFRg5jVdin8+VgaUT/6u4PcLwu7X0maIQunWmbPXllWmP+EjZu3imo/41NbfyLBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b6b6791909e81d331e1760b19531fa8b268b9f9330dac1f6871de844b379926c","last_reissued_at":"2026-05-17T23:47:08.118050Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:47:08.118050Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1905.00963","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:47:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ESvbDvLkhjTSce9zlyHaQ64LL7Xo0Z9PnCrwPbZJATkoFpDplGqfE3l4hocISlGPUpU5bTIFFW0YfhpY2V2mBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-25T20:04:05.551894Z"},"content_sha256":"f6e7c3181990287dde2a8929fa3fcb219646446a48fe6746cc2cb6949c4e4a75","schema_version":"1.0","event_id":"sha256:f6e7c3181990287dde2a8929fa3fcb219646446a48fe6746cc2cb6949c4e4a75"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:W23HSGIJ5AOTGHQXMCYZKMP2RM","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"S-parameter calibration procedure for multiport microwave imaging systems","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"eess.SP","authors_text":"Ferry Kienberger, Georg Gramse, Manuel Kasper, Mykolas Ragulskis","submitted_at":"2019-05-01T12:42:25Z","abstract_excerpt":"Multitude of antennas are typically used in microwave imaging systems. Here we outline a simple and effective calibration method for multiport imaging systems. By using only one additional component, an electronic calibration module (ECal), one port is calibrated and the calibration plane is thereby moved to the antenna connector. Assuming all antennas interact with the test phantom in the same way, the one-port calibration is transferred to all other antennas. For full calibration including the transmission path between antennas, the unknown thru technique is used. This calibration procedure "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1905.00963","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:47:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"eOvcNT5oD/Cy1N0QNVuFIZou+Bs8AzqASxfdcqpPiAecYOZatEa7oTdO7mj0RSlTIGYUQmI4gybvX2dqtAg0Cg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-25T20:04:05.552233Z"},"content_sha256":"e64ae3750068ab482d3237e8b220ade4706495d9879694c5adbc63f160b4385c","schema_version":"1.0","event_id":"sha256:e64ae3750068ab482d3237e8b220ade4706495d9879694c5adbc63f160b4385c"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/bundle.json","state_url":"https://pith.science/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-25T20:04:05Z","links":{"resolver":"https://pith.science/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM","bundle":"https://pith.science/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/bundle.json","state":"https://pith.science/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/state.json","well_known_bundle":"https://pith.science/.well-known/pith/W23HSGIJ5AOTGHQXMCYZKMP2RM/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:W23HSGIJ5AOTGHQXMCYZKMP2RM","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"153c8fce7f3a2068ed76ccbc4984cf229d38cf23777c0b2ffb380b6b0a7344a3","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"eess.SP","submitted_at":"2019-05-01T12:42:25Z","title_canon_sha256":"db1920de177b77c8e2aa6a5708302a1fc6dd07df85d46de087ad2afe37111667"},"schema_version":"1.0","source":{"id":"1905.00963","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1905.00963","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"arxiv_version","alias_value":"1905.00963v1","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1905.00963","created_at":"2026-05-17T23:47:08Z"},{"alias_kind":"pith_short_12","alias_value":"W23HSGIJ5AOT","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_16","alias_value":"W23HSGIJ5AOTGHQX","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_8","alias_value":"W23HSGIJ","created_at":"2026-05-18T12:33:30Z"}],"graph_snapshots":[{"event_id":"sha256:e64ae3750068ab482d3237e8b220ade4706495d9879694c5adbc63f160b4385c","target":"graph","created_at":"2026-05-17T23:47:08Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Multitude of antennas are typically used in microwave imaging systems. Here we outline a simple and effective calibration method for multiport imaging systems. By using only one additional component, an electronic calibration module (ECal), one port is calibrated and the calibration plane is thereby moved to the antenna connector. Assuming all antennas interact with the test phantom in the same way, the one-port calibration is transferred to all other antennas. For full calibration including the transmission path between antennas, the unknown thru technique is used. This calibration procedure ","authors_text":"Ferry Kienberger, Georg Gramse, Manuel Kasper, Mykolas Ragulskis","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"eess.SP","submitted_at":"2019-05-01T12:42:25Z","title":"S-parameter calibration procedure for multiport microwave imaging systems"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1905.00963","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:f6e7c3181990287dde2a8929fa3fcb219646446a48fe6746cc2cb6949c4e4a75","target":"record","created_at":"2026-05-17T23:47:08Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"153c8fce7f3a2068ed76ccbc4984cf229d38cf23777c0b2ffb380b6b0a7344a3","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"eess.SP","submitted_at":"2019-05-01T12:42:25Z","title_canon_sha256":"db1920de177b77c8e2aa6a5708302a1fc6dd07df85d46de087ad2afe37111667"},"schema_version":"1.0","source":{"id":"1905.00963","kind":"arxiv","version":1}},"canonical_sha256":"b6b6791909e81d331e1760b19531fa8b268b9f9330dac1f6871de844b379926c","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b6b6791909e81d331e1760b19531fa8b268b9f9330dac1f6871de844b379926c","first_computed_at":"2026-05-17T23:47:08.118050Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:47:08.118050Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"5a/odZmq3qKAGAHkrCF0HKCFRg5jVdin8+VgaUT/6u4PcLwu7X0maIQunWmbPXllWmP+EjZu3imo/41NbfyLBg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:47:08.118573Z","signed_message":"canonical_sha256_bytes"},"source_id":"1905.00963","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f6e7c3181990287dde2a8929fa3fcb219646446a48fe6746cc2cb6949c4e4a75","sha256:e64ae3750068ab482d3237e8b220ade4706495d9879694c5adbc63f160b4385c"],"state_sha256":"a1e847994d2f3f28b7c843441ba7e2454888d6334b0ef3378eb7d28c3167ab43"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"jI8kPAxjNdtc1W/W+po7xIdRch+4ijqy5wPUj/LTrGqiQBRiYotD2W6z3AJIThglG8Bkn2n+w+wvdeUY491GDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-25T20:04:05.554165Z","bundle_sha256":"196efe9dc5361d0233c1df4e52cbc11d896ad51a0542ff75190cae4f42213878"}}