{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2015:Y6HQSLJLAFFS4QFH4IFJSEBUML","short_pith_number":"pith:Y6HQSLJL","schema_version":"1.0","canonical_sha256":"c78f092d2b014b2e40a7e20a99103462eb721bd861c859aa86383e44cfc8ae48","source":{"kind":"arxiv","id":"1510.04122","version":1},"attestation_state":"computed","paper":{"title":"Eigenfunctions of Underspread Linear Communication Systems","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.IT"],"primary_cat":"cs.IT","authors_text":"Mikhail Tsitsvero, Sergio Barbarossa","submitted_at":"2015-10-14T14:42:00Z","abstract_excerpt":"In this paper we show that the eigenfunctions can be found exactly for systems whose delay-Doppler spread function is concentrated along a straight line and they can be found in approximate sense for systems having a spread function maximally concentrated in regions of the Doppler-delay plane whose area is smaller than one. The interesting results are that: i) the instantaneous frequency of the eigenfunctions is dictated by the contour level of the time-varying transfer function; ii) the eigenvalues are restricted between the minimum and maximum value of the system time-varying transfer functi"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1510.04122","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2015-10-14T14:42:00Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"0ee27b264ce905ec435e82c429a64fb66c37c06936d70d5a05e362411c3ad134","abstract_canon_sha256":"8d8b61f18eb4d060f4a9c4c3f1817a385756f6d00a29003d301aa86c4ee08590"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:30:09.161459Z","signature_b64":"rOHXHZbYQnftNJdyScNw/vICcOVB8+FDSsMUyhwKNkJdABJxGZpy96JVS8pj41AOwnmEJSCycF7nqobufMQEBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c78f092d2b014b2e40a7e20a99103462eb721bd861c859aa86383e44cfc8ae48","last_reissued_at":"2026-05-18T01:30:09.160858Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:30:09.160858Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Eigenfunctions of Underspread Linear Communication Systems","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.IT"],"primary_cat":"cs.IT","authors_text":"Mikhail Tsitsvero, Sergio Barbarossa","submitted_at":"2015-10-14T14:42:00Z","abstract_excerpt":"In this paper we show that the eigenfunctions can be found exactly for systems whose delay-Doppler spread function is concentrated along a straight line and they can be found in approximate sense for systems having a spread function maximally concentrated in regions of the Doppler-delay plane whose area is smaller than one. The interesting results are that: i) the instantaneous frequency of the eigenfunctions is dictated by the contour level of the time-varying transfer function; ii) the eigenvalues are restricted between the minimum and maximum value of the system time-varying transfer functi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1510.04122","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1510.04122","created_at":"2026-05-18T01:30:09.160940+00:00"},{"alias_kind":"arxiv_version","alias_value":"1510.04122v1","created_at":"2026-05-18T01:30:09.160940+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1510.04122","created_at":"2026-05-18T01:30:09.160940+00:00"},{"alias_kind":"pith_short_12","alias_value":"Y6HQSLJLAFFS","created_at":"2026-05-18T12:29:50.041715+00:00"},{"alias_kind":"pith_short_16","alias_value":"Y6HQSLJLAFFS4QFH","created_at":"2026-05-18T12:29:50.041715+00:00"},{"alias_kind":"pith_short_8","alias_value":"Y6HQSLJL","created_at":"2026-05-18T12:29:50.041715+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML","json":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML.json","graph_json":"https://pith.science/api/pith-number/Y6HQSLJLAFFS4QFH4IFJSEBUML/graph.json","events_json":"https://pith.science/api/pith-number/Y6HQSLJLAFFS4QFH4IFJSEBUML/events.json","paper":"https://pith.science/paper/Y6HQSLJL"},"agent_actions":{"view_html":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML","download_json":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML.json","view_paper":"https://pith.science/paper/Y6HQSLJL","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1510.04122&json=true","fetch_graph":"https://pith.science/api/pith-number/Y6HQSLJLAFFS4QFH4IFJSEBUML/graph.json","fetch_events":"https://pith.science/api/pith-number/Y6HQSLJLAFFS4QFH4IFJSEBUML/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML/action/timestamp_anchor","attest_storage":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML/action/storage_attestation","attest_author":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML/action/author_attestation","sign_citation":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML/action/citation_signature","submit_replication":"https://pith.science/pith/Y6HQSLJLAFFS4QFH4IFJSEBUML/action/replication_record"}},"created_at":"2026-05-18T01:30:09.160940+00:00","updated_at":"2026-05-18T01:30:09.160940+00:00"}