{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:MML6PNNAODE7FXERNXTIE6KA3O","short_pith_number":"pith:MML6PNNA","canonical_record":{"source":{"id":"1302.1351","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2013-02-06T13:03:11Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"a53c9af84d239f4a1b3af92d3ad606847e8c8c97d400c621e5d930548e0d2e83","abstract_canon_sha256":"b43500902e75c89eee154bd5c2e4247032d5fb54fd2984cf5b059f307685a606"},"schema_version":"1.0"},"canonical_sha256":"6317e7b5a070c9f2dc916de6827940dbb2f9eff7ec6b03430651c69eb1333db6","source":{"kind":"arxiv","id":"1302.1351","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1302.1351","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"arxiv_version","alias_value":"1302.1351v1","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1302.1351","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"pith_short_12","alias_value":"MML6PNNAODE7","created_at":"2026-05-18T12:27:52Z"},{"alias_kind":"pith_short_16","alias_value":"MML6PNNAODE7FXER","created_at":"2026-05-18T12:27:52Z"},{"alias_kind":"pith_short_8","alias_value":"MML6PNNA","created_at":"2026-05-18T12:27:52Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:MML6PNNAODE7FXERNXTIE6KA3O","target":"record","payload":{"canonical_record":{"source":{"id":"1302.1351","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2013-02-06T13:03:11Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"a53c9af84d239f4a1b3af92d3ad606847e8c8c97d400c621e5d930548e0d2e83","abstract_canon_sha256":"b43500902e75c89eee154bd5c2e4247032d5fb54fd2984cf5b059f307685a606"},"schema_version":"1.0"},"canonical_sha256":"6317e7b5a070c9f2dc916de6827940dbb2f9eff7ec6b03430651c69eb1333db6","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:34:24.491514Z","signature_b64":"Q4PLmOQrdkVh5JCKwi1LBjS9FHen0zRp0Wq/f4Kk4DT5OPCFxi4YnSJKDUI8BPptoSuFdfLk0Utr3ZOoVPCQBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6317e7b5a070c9f2dc916de6827940dbb2f9eff7ec6b03430651c69eb1333db6","last_reissued_at":"2026-05-18T03:34:24.490968Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:34:24.490968Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1302.1351","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":"2026-05-18T03:34:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"gJnxpPU9tFDzEZY0rW7PKAPS5sHb12WTxiWPzFPedzOXyy71wrbH+aJSXMzD0qxBd1D+a+qZaPF3UocnqifXAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T00:56:19.523989Z"},"content_sha256":"462c8ca056c9e187db004868b962ba8fe9cd9a78e6ac5d22acf1d7f6e5e2197b","schema_version":"1.0","event_id":"sha256:462c8ca056c9e187db004868b962ba8fe9cd9a78e6ac5d22acf1d7f6e5e2197b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:MML6PNNAODE7FXERNXTIE6KA3O","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Adaptive Sparse Channel Estimation for Time-Variant MIMO-OFDM Systems","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.IT"],"primary_cat":"cs.IT","authors_text":"Fumiyuki Adachi, Guan Gui, Wei Peng","submitted_at":"2013-02-06T13:03:11Z","abstract_excerpt":"Accurate channel state information (CSI) is required for coherent detection in time-variant multiple-input multipleoutput (MIMO) communication systems using orthogonal frequency division multiplexing (OFDM) modulation. One of low-complexity and stable adaptive channel estimation (ACE) approaches is the normalized least mean square (NLMS)-based ACE. However, it cannot exploit the inherent sparsity of MIMO channel which is characterized by a few dominant channel taps. In this paper, we propose two adaptive sparse channel estimation (ASCE) methods to take advantage of such sparse structure inform"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1302.1351","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":"2026-05-18T03:34:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"uxTqICNx+oRMEtjE9H8ddYij6mTKMnti9YvpeWTJzAIgfnL4TRxwwLg2l0pjABqepGQ8+stnxaoqtFQuHHGZCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T00:56:19.524354Z"},"content_sha256":"8e030f6134c85c301b836f5dba7f2c83c172d62d600295c26f02bfd7aa911232","schema_version":"1.0","event_id":"sha256:8e030f6134c85c301b836f5dba7f2c83c172d62d600295c26f02bfd7aa911232"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/MML6PNNAODE7FXERNXTIE6KA3O/bundle.json","state_url":"https://pith.science/pith/MML6PNNAODE7FXERNXTIE6KA3O/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/MML6PNNAODE7FXERNXTIE6KA3O/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":"2026-06-03T00:56:19Z","links":{"resolver":"https://pith.science/pith/MML6PNNAODE7FXERNXTIE6KA3O","bundle":"https://pith.science/pith/MML6PNNAODE7FXERNXTIE6KA3O/bundle.json","state":"https://pith.science/pith/MML6PNNAODE7FXERNXTIE6KA3O/state.json","well_known_bundle":"https://pith.science/.well-known/pith/MML6PNNAODE7FXERNXTIE6KA3O/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:MML6PNNAODE7FXERNXTIE6KA3O","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":"b43500902e75c89eee154bd5c2e4247032d5fb54fd2984cf5b059f307685a606","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2013-02-06T13:03:11Z","title_canon_sha256":"a53c9af84d239f4a1b3af92d3ad606847e8c8c97d400c621e5d930548e0d2e83"},"schema_version":"1.0","source":{"id":"1302.1351","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1302.1351","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"arxiv_version","alias_value":"1302.1351v1","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1302.1351","created_at":"2026-05-18T03:34:24Z"},{"alias_kind":"pith_short_12","alias_value":"MML6PNNAODE7","created_at":"2026-05-18T12:27:52Z"},{"alias_kind":"pith_short_16","alias_value":"MML6PNNAODE7FXER","created_at":"2026-05-18T12:27:52Z"},{"alias_kind":"pith_short_8","alias_value":"MML6PNNA","created_at":"2026-05-18T12:27:52Z"}],"graph_snapshots":[{"event_id":"sha256:8e030f6134c85c301b836f5dba7f2c83c172d62d600295c26f02bfd7aa911232","target":"graph","created_at":"2026-05-18T03:34:24Z","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":"Accurate channel state information (CSI) is required for coherent detection in time-variant multiple-input multipleoutput (MIMO) communication systems using orthogonal frequency division multiplexing (OFDM) modulation. One of low-complexity and stable adaptive channel estimation (ACE) approaches is the normalized least mean square (NLMS)-based ACE. However, it cannot exploit the inherent sparsity of MIMO channel which is characterized by a few dominant channel taps. In this paper, we propose two adaptive sparse channel estimation (ASCE) methods to take advantage of such sparse structure inform","authors_text":"Fumiyuki Adachi, Guan Gui, Wei Peng","cross_cats":["math.IT"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2013-02-06T13:03:11Z","title":"Adaptive Sparse Channel Estimation for Time-Variant MIMO-OFDM Systems"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1302.1351","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":"sha256:462c8ca056c9e187db004868b962ba8fe9cd9a78e6ac5d22acf1d7f6e5e2197b","target":"record","created_at":"2026-05-18T03:34:24Z","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":"b43500902e75c89eee154bd5c2e4247032d5fb54fd2984cf5b059f307685a606","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2013-02-06T13:03:11Z","title_canon_sha256":"a53c9af84d239f4a1b3af92d3ad606847e8c8c97d400c621e5d930548e0d2e83"},"schema_version":"1.0","source":{"id":"1302.1351","kind":"arxiv","version":1}},"canonical_sha256":"6317e7b5a070c9f2dc916de6827940dbb2f9eff7ec6b03430651c69eb1333db6","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6317e7b5a070c9f2dc916de6827940dbb2f9eff7ec6b03430651c69eb1333db6","first_computed_at":"2026-05-18T03:34:24.490968Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:34:24.490968Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Q4PLmOQrdkVh5JCKwi1LBjS9FHen0zRp0Wq/f4Kk4DT5OPCFxi4YnSJKDUI8BPptoSuFdfLk0Utr3ZOoVPCQBQ==","signature_status":"signed_v1","signed_at":"2026-05-18T03:34:24.491514Z","signed_message":"canonical_sha256_bytes"},"source_id":"1302.1351","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:462c8ca056c9e187db004868b962ba8fe9cd9a78e6ac5d22acf1d7f6e5e2197b","sha256:8e030f6134c85c301b836f5dba7f2c83c172d62d600295c26f02bfd7aa911232"],"state_sha256":"601506243f7a7bdbf482da5a1efa178126b124151a51824064e00e4b5c11d1af"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qYhUIO+Ftntr8K18R5lUfUUlJH58rPoscgrNq0bBXQk5LgS/LmYMP3fTBwP6eAJUBHwDqo6gEAHjz1VyzcceDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-03T00:56:19.526340Z","bundle_sha256":"bf94de99be36c3ce5582f7565a5bd8343e6190f58b1fe1a76aa5505ce7798a3e"}}