{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2025:6OW42EF5ZITP2R4SFIJMQIYDMK","short_pith_number":"pith:6OW42EF5","canonical_record":{"source":{"id":"2505.08267","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2025-05-13T06:32:24Z","cross_cats_sorted":[],"title_canon_sha256":"b529a84f25f6ec90b429b4624f1e8b07da67ce075caf42c1fad9e8fddbc0a3cb","abstract_canon_sha256":"8f6a7cf010054959c41dcd262b9fd034a0a3cb9a8b228c5afd9d89c6f51763af"},"schema_version":"1.0"},"canonical_sha256":"f3adcd10bdca26fd47922a12c82303629c9dbb6df1d4d8369021dd5b4baf8005","source":{"kind":"arxiv","id":"2505.08267","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2505.08267","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"arxiv_version","alias_value":"2505.08267v1","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2505.08267","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_12","alias_value":"6OW42EF5ZITP","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_16","alias_value":"6OW42EF5ZITP2R4S","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_8","alias_value":"6OW42EF5","created_at":"2026-07-05T11:02:27Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2025:6OW42EF5ZITP2R4SFIJMQIYDMK","target":"record","payload":{"canonical_record":{"source":{"id":"2505.08267","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2025-05-13T06:32:24Z","cross_cats_sorted":[],"title_canon_sha256":"b529a84f25f6ec90b429b4624f1e8b07da67ce075caf42c1fad9e8fddbc0a3cb","abstract_canon_sha256":"8f6a7cf010054959c41dcd262b9fd034a0a3cb9a8b228c5afd9d89c6f51763af"},"schema_version":"1.0"},"canonical_sha256":"f3adcd10bdca26fd47922a12c82303629c9dbb6df1d4d8369021dd5b4baf8005","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T11:02:27.476882Z","signature_b64":"eXOXUydbqgOgjgVzNYrzpYM1VTf4byIE3H5LBOzE15xUjNPsQ1c6/mjQTuLkAfSAKY4wnwJ4LmUU5MYfRSrECA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f3adcd10bdca26fd47922a12c82303629c9dbb6df1d4d8369021dd5b4baf8005","last_reissued_at":"2026-07-05T11:02:27.476298Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T11:02:27.476298Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2505.08267","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":"2026-07-05T11:02:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9mR2L0g9QT+nIJhF3x01st8yMxI3zqNREN2nGPjLg2Y2fbG0fdDsBO3hgSc8OgK5d6TcvWJTclGOunJxaJgaDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-22T20:18:27.332928Z"},"content_sha256":"041cb211c21f4d98a3d5e533d6533fcf51d98a65e8eb112ca50b78a5d7bb656f","schema_version":"1.0","event_id":"sha256:041cb211c21f4d98a3d5e533d6533fcf51d98a65e8eb112ca50b78a5d7bb656f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2025:6OW42EF5ZITP2R4SFIJMQIYDMK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Sparsity-Aware Near-Field Beam Training via Multi-Beam Combination","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"eess.SP","authors_text":"Chien-Hua Chen, Jinesh Nair, Rama Kiran, Rui Zhang, Shawn Tsai, Tzu-Han Chou, Zijun Wang","submitted_at":"2025-05-13T06:32:24Z","abstract_excerpt":"This paper proposes an adaptive near-field beam training method to enhance performance in multi-user and multipath environments. The approach identifies multiple strongest beams through beam sweeping and linearly combines their received signals - capturing both amplitude and phase - for improved channel estimation. Two codebooks are considered: the conventional DFT codebook and a near-field codebook that samples both angular and distance domains. As the near-field basis functions are generally non-orthogonal and often over-complete, we exploit sparsity in the solution using LASSO-based linear "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2505.08267","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2505.08267/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T11:02:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AyuPHRZ0/dhRGZRaBoOLCjnGO3FCzFOO1I8TXhu4bII5A4jXIUHx/il11idOvRjrEf61gLlr/e2BnywybXLbCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-22T20:18:27.333420Z"},"content_sha256":"522ad1daf498cf612238c4e9df4b224a195b888756e37dba21cd179123cfdf92","schema_version":"1.0","event_id":"sha256:522ad1daf498cf612238c4e9df4b224a195b888756e37dba21cd179123cfdf92"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/bundle.json","state_url":"https://pith.science/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/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":"2026-08-22T20:18:27Z","links":{"resolver":"https://pith.science/pith/6OW42EF5ZITP2R4SFIJMQIYDMK","bundle":"https://pith.science/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/bundle.json","state":"https://pith.science/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/6OW42EF5ZITP2R4SFIJMQIYDMK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:6OW42EF5ZITP2R4SFIJMQIYDMK","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":"8f6a7cf010054959c41dcd262b9fd034a0a3cb9a8b228c5afd9d89c6f51763af","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2025-05-13T06:32:24Z","title_canon_sha256":"b529a84f25f6ec90b429b4624f1e8b07da67ce075caf42c1fad9e8fddbc0a3cb"},"schema_version":"1.0","source":{"id":"2505.08267","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2505.08267","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"arxiv_version","alias_value":"2505.08267v1","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2505.08267","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_12","alias_value":"6OW42EF5ZITP","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_16","alias_value":"6OW42EF5ZITP2R4S","created_at":"2026-07-05T11:02:27Z"},{"alias_kind":"pith_short_8","alias_value":"6OW42EF5","created_at":"2026-07-05T11:02:27Z"}],"graph_snapshots":[{"event_id":"sha256:522ad1daf498cf612238c4e9df4b224a195b888756e37dba21cd179123cfdf92","target":"graph","created_at":"2026-07-05T11:02:27Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2505.08267/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"This paper proposes an adaptive near-field beam training method to enhance performance in multi-user and multipath environments. The approach identifies multiple strongest beams through beam sweeping and linearly combines their received signals - capturing both amplitude and phase - for improved channel estimation. Two codebooks are considered: the conventional DFT codebook and a near-field codebook that samples both angular and distance domains. As the near-field basis functions are generally non-orthogonal and often over-complete, we exploit sparsity in the solution using LASSO-based linear ","authors_text":"Chien-Hua Chen, Jinesh Nair, Rama Kiran, Rui Zhang, Shawn Tsai, Tzu-Han Chou, Zijun Wang","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2025-05-13T06:32:24Z","title":"Sparsity-Aware Near-Field Beam Training via Multi-Beam Combination"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2505.08267","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":"sha256:041cb211c21f4d98a3d5e533d6533fcf51d98a65e8eb112ca50b78a5d7bb656f","target":"record","created_at":"2026-07-05T11:02:27Z","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":"8f6a7cf010054959c41dcd262b9fd034a0a3cb9a8b228c5afd9d89c6f51763af","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2025-05-13T06:32:24Z","title_canon_sha256":"b529a84f25f6ec90b429b4624f1e8b07da67ce075caf42c1fad9e8fddbc0a3cb"},"schema_version":"1.0","source":{"id":"2505.08267","kind":"arxiv","version":1}},"canonical_sha256":"f3adcd10bdca26fd47922a12c82303629c9dbb6df1d4d8369021dd5b4baf8005","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f3adcd10bdca26fd47922a12c82303629c9dbb6df1d4d8369021dd5b4baf8005","first_computed_at":"2026-07-05T11:02:27.476298Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T11:02:27.476298Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"eXOXUydbqgOgjgVzNYrzpYM1VTf4byIE3H5LBOzE15xUjNPsQ1c6/mjQTuLkAfSAKY4wnwJ4LmUU5MYfRSrECA==","signature_status":"signed_v1","signed_at":"2026-07-05T11:02:27.476882Z","signed_message":"canonical_sha256_bytes"},"source_id":"2505.08267","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:041cb211c21f4d98a3d5e533d6533fcf51d98a65e8eb112ca50b78a5d7bb656f","sha256:522ad1daf498cf612238c4e9df4b224a195b888756e37dba21cd179123cfdf92"],"state_sha256":"bd743f9c0b3ef71fda23db958cdf0324f210085acdafc8c7788a199bd828bd10"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"gtc72l7cSkdABI6Rb6bLJRIVirWeT8jXmqhclV3OS+sAy0JNFEV49qVeWeyilEbV6DXSfe+jHFIdMV2w7HAkCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-22T20:18:27.337805Z","bundle_sha256":"095063c1f821201179b11d2d62475729fdcde000865031848a077b5cc5d83246"}}