{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2014:KJWOZYDNXZ35FHY2KGBJBPXJS2","short_pith_number":"pith:KJWOZYDN","canonical_record":{"source":{"id":"1403.4847","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2014-03-19T15:38:33Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"edf5241724a6b3f4e46306eecc5eba0aed0ddc57cacbe8b23a897f60a86af483","abstract_canon_sha256":"cbc6e304eb71f3a1b7b88db99a96c8c159e423591a6e33551cc15eab2712165c"},"schema_version":"1.0"},"canonical_sha256":"526cece06dbe77d29f1a518290bee996b3236fd6492716e5910e2683fc745a24","source":{"kind":"arxiv","id":"1403.4847","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.4847","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"arxiv_version","alias_value":"1403.4847v1","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.4847","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"pith_short_12","alias_value":"KJWOZYDNXZ35","created_at":"2026-05-18T12:28:35Z"},{"alias_kind":"pith_short_16","alias_value":"KJWOZYDNXZ35FHY2","created_at":"2026-05-18T12:28:35Z"},{"alias_kind":"pith_short_8","alias_value":"KJWOZYDN","created_at":"2026-05-18T12:28:35Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2014:KJWOZYDNXZ35FHY2KGBJBPXJS2","target":"record","payload":{"canonical_record":{"source":{"id":"1403.4847","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2014-03-19T15:38:33Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"edf5241724a6b3f4e46306eecc5eba0aed0ddc57cacbe8b23a897f60a86af483","abstract_canon_sha256":"cbc6e304eb71f3a1b7b88db99a96c8c159e423591a6e33551cc15eab2712165c"},"schema_version":"1.0"},"canonical_sha256":"526cece06dbe77d29f1a518290bee996b3236fd6492716e5910e2683fc745a24","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:56:04.332881Z","signature_b64":"4i28iblCQ7MfNwLtXEaynQ/biCrjTaYtqPm4jgL33KbWf2D+8nrqIW/0RA1HvJsMo9KjDnd91HzfxRT9GnaUCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"526cece06dbe77d29f1a518290bee996b3236fd6492716e5910e2683fc745a24","last_reissued_at":"2026-05-18T02:56:04.332414Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:56:04.332414Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1403.4847","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":"2026-05-18T02:56:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"HrAkdswZzFedNuzxHyYIpN17neWcx/ibdgkClwtbr85AhtAyiAyReJI6onWbteWKtKCtGsKVUl43Tlu5O/CSDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T16:31:26.109409Z"},"content_sha256":"d0dd5961447c7a04a508567bd7f0da35c1c0fe0c5c21b9607cfbd2147a8c0965","schema_version":"1.0","event_id":"sha256:d0dd5961447c7a04a508567bd7f0da35c1c0fe0c5c21b9607cfbd2147a8c0965"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2014:KJWOZYDNXZ35FHY2KGBJBPXJS2","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Massive MIMO Systems with Hardware-Constrained Base Stations","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.IT"],"primary_cat":"cs.IT","authors_text":"Emil Bj\\\"ornson, M\\'erouane Debbah, Michail Matthaiou","submitted_at":"2014-03-19T15:38:33Z","abstract_excerpt":"Massive multiple-input multiple-output (MIMO) systems are cellular networks where the base stations (BSs) are equipped with unconventionally many antennas. Such large antenna arrays offer huge spatial degrees-of-freedom for transmission optimization; in particular, great signal gains, resilience to imperfect channel knowledge, and small inter-user interference are all achievable without extensive inter-cell coordination. The key to cost-efficient deployment of large arrays is the use of hardware-constrained base stations with low-cost antenna elements, as compared to today's expensive and powe"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.4847","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":"2026-05-18T02:56:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ULNWcqwUZzvM/pdFfQltks3vqQw8u8L79M5QiCPurBuSF2QQUvDVdgUhYpLgHpcgohErn8gTrDLJHL2LbS9MDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T16:31:26.109780Z"},"content_sha256":"7bff8640c01a5f0d8c5eb9b5c28087f1cde26151db1bd9b7bcc7e16198c90ae0","schema_version":"1.0","event_id":"sha256:7bff8640c01a5f0d8c5eb9b5c28087f1cde26151db1bd9b7bcc7e16198c90ae0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/bundle.json","state_url":"https://pith.science/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/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":"2026-06-02T16:31:26Z","links":{"resolver":"https://pith.science/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2","bundle":"https://pith.science/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/bundle.json","state":"https://pith.science/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/state.json","well_known_bundle":"https://pith.science/.well-known/pith/KJWOZYDNXZ35FHY2KGBJBPXJS2/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:KJWOZYDNXZ35FHY2KGBJBPXJS2","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":"cbc6e304eb71f3a1b7b88db99a96c8c159e423591a6e33551cc15eab2712165c","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2014-03-19T15:38:33Z","title_canon_sha256":"edf5241724a6b3f4e46306eecc5eba0aed0ddc57cacbe8b23a897f60a86af483"},"schema_version":"1.0","source":{"id":"1403.4847","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.4847","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"arxiv_version","alias_value":"1403.4847v1","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.4847","created_at":"2026-05-18T02:56:04Z"},{"alias_kind":"pith_short_12","alias_value":"KJWOZYDNXZ35","created_at":"2026-05-18T12:28:35Z"},{"alias_kind":"pith_short_16","alias_value":"KJWOZYDNXZ35FHY2","created_at":"2026-05-18T12:28:35Z"},{"alias_kind":"pith_short_8","alias_value":"KJWOZYDN","created_at":"2026-05-18T12:28:35Z"}],"graph_snapshots":[{"event_id":"sha256:7bff8640c01a5f0d8c5eb9b5c28087f1cde26151db1bd9b7bcc7e16198c90ae0","target":"graph","created_at":"2026-05-18T02:56:04Z","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":"Massive multiple-input multiple-output (MIMO) systems are cellular networks where the base stations (BSs) are equipped with unconventionally many antennas. Such large antenna arrays offer huge spatial degrees-of-freedom for transmission optimization; in particular, great signal gains, resilience to imperfect channel knowledge, and small inter-user interference are all achievable without extensive inter-cell coordination. The key to cost-efficient deployment of large arrays is the use of hardware-constrained base stations with low-cost antenna elements, as compared to today's expensive and powe","authors_text":"Emil Bj\\\"ornson, M\\'erouane Debbah, Michail Matthaiou","cross_cats":["math.IT"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2014-03-19T15:38:33Z","title":"Massive MIMO Systems with Hardware-Constrained Base Stations"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.4847","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:d0dd5961447c7a04a508567bd7f0da35c1c0fe0c5c21b9607cfbd2147a8c0965","target":"record","created_at":"2026-05-18T02:56:04Z","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":"cbc6e304eb71f3a1b7b88db99a96c8c159e423591a6e33551cc15eab2712165c","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2014-03-19T15:38:33Z","title_canon_sha256":"edf5241724a6b3f4e46306eecc5eba0aed0ddc57cacbe8b23a897f60a86af483"},"schema_version":"1.0","source":{"id":"1403.4847","kind":"arxiv","version":1}},"canonical_sha256":"526cece06dbe77d29f1a518290bee996b3236fd6492716e5910e2683fc745a24","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"526cece06dbe77d29f1a518290bee996b3236fd6492716e5910e2683fc745a24","first_computed_at":"2026-05-18T02:56:04.332414Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:56:04.332414Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4i28iblCQ7MfNwLtXEaynQ/biCrjTaYtqPm4jgL33KbWf2D+8nrqIW/0RA1HvJsMo9KjDnd91HzfxRT9GnaUCg==","signature_status":"signed_v1","signed_at":"2026-05-18T02:56:04.332881Z","signed_message":"canonical_sha256_bytes"},"source_id":"1403.4847","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d0dd5961447c7a04a508567bd7f0da35c1c0fe0c5c21b9607cfbd2147a8c0965","sha256:7bff8640c01a5f0d8c5eb9b5c28087f1cde26151db1bd9b7bcc7e16198c90ae0"],"state_sha256":"6e4223a2e79f038f2fbda17fcb6e510041770854190f8cbe64d949c14fc9f86c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vGGPnyUORwuGS4hzIxRBAZ4l39lK9zRx7i+ZwSRWxulQ6POBsV0GJ8mcwm6IVeBioFOv6o/SV0uCEczEhQ6iAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-02T16:31:26.111845Z","bundle_sha256":"f38c47058de26f3ee5b721acf681c3954be956e4f64bcb60a2e23732d3c56ceb"}}