{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:X4L55ZZH6SRUY5EKWA7O77C2AF","short_pith_number":"pith:X4L55ZZH","canonical_record":{"source":{"id":"1903.05928","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2019-03-14T11:56:31Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"0f189151d48595caba1229a4725327c1061d370187def2efc764c92af3d0d0f8","abstract_canon_sha256":"0a4177315d428ce67b4de08a69000e63d0cccc608cd7cf158191e31823e3e978"},"schema_version":"1.0"},"canonical_sha256":"bf17dee727f4a34c748ab03eeffc5a01638330b3f1f15533dff688707ffa13eb","source":{"kind":"arxiv","id":"1903.05928","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.05928","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"arxiv_version","alias_value":"1903.05928v2","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.05928","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_12","alias_value":"X4L55ZZH6SRU","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_16","alias_value":"X4L55ZZH6SRUY5EK","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_8","alias_value":"X4L55ZZH","created_at":"2026-07-05T01:28:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:X4L55ZZH6SRUY5EKWA7O77C2AF","target":"record","payload":{"canonical_record":{"source":{"id":"1903.05928","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2019-03-14T11:56:31Z","cross_cats_sorted":["math.IT"],"title_canon_sha256":"0f189151d48595caba1229a4725327c1061d370187def2efc764c92af3d0d0f8","abstract_canon_sha256":"0a4177315d428ce67b4de08a69000e63d0cccc608cd7cf158191e31823e3e978"},"schema_version":"1.0"},"canonical_sha256":"bf17dee727f4a34c748ab03eeffc5a01638330b3f1f15533dff688707ffa13eb","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T01:28:28.145001Z","signature_b64":"DuYrn7U9gSxoIt/O16VBkqKlRd9ZsoJ83Bz9tbaGMGc9SC71joFK0fLF2n24TmXsG7sLuy2zJHvInzIkZ10mAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"bf17dee727f4a34c748ab03eeffc5a01638330b3f1f15533dff688707ffa13eb","last_reissued_at":"2026-07-05T01:28:28.144486Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T01:28:28.144486Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1903.05928","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T01:28:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"FAb4WcEzv7x5YaakJXwr2D5rzSNyJbTPUfGb3+Fv2qDy0WYAPTQVMPIAloVQ7HrbV3tH+ul8xcAmr9akrp1wCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-17T07:35:32.629828Z"},"content_sha256":"b69212d597c124c877fe62bc7e341105cc77db4cfd537fb8bd2aa8d3e90a01bd","schema_version":"1.0","event_id":"sha256:b69212d597c124c877fe62bc7e341105cc77db4cfd537fb8bd2aa8d3e90a01bd"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:X4L55ZZH6SRUY5EKWA7O77C2AF","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Channel Estimation and Hybrid Precoding for Distributed Phased Arrays Based MIMO Wireless Communications","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.IT"],"primary_cat":"cs.IT","authors_text":"Dongming Wang, Xiaodai Dong, Xiaohu You, Yiming Huo, Yu Zhang","submitted_at":"2019-03-14T11:56:31Z","abstract_excerpt":"Distributed phased arrays based multiple-input multiple-output (DPA-MIMO) is a newly introduced architecture that enables both spatial multiplexing and beamforming while facilitating highly reconfigurable hardware implementation in millimeter-wave (mmWave) frequency bands. With a DPA-MIMO system, we focus on channel state information (CSI) acquisition and hybrid precoding. As benefited from a coordinated and open-loop pilot beam pattern design, all the sub-arrays can perform channel sounding with less training overhead compared with the traditional orthogonal operation of each sub-array. Furth"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.05928","kind":"arxiv","version":2},"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/1903.05928/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":"2026-07-05T01:28:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"tm+O4NTTSgY2GnvNLpJph7Y7AIQEqR/sQpO+VOS5NUoSfwwvy7fvAWOK1uOY1L9E9igbTNnwOElH8inGWGBuDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-17T07:35:32.630438Z"},"content_sha256":"998c45a7e0f431b44a8486bb4c2ee1639a9efff988e294fae39959e38fab26bb","schema_version":"1.0","event_id":"sha256:998c45a7e0f431b44a8486bb4c2ee1639a9efff988e294fae39959e38fab26bb"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/bundle.json","state_url":"https://pith.science/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/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":"2026-08-17T07:35:32Z","links":{"resolver":"https://pith.science/pith/X4L55ZZH6SRUY5EKWA7O77C2AF","bundle":"https://pith.science/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/bundle.json","state":"https://pith.science/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/state.json","well_known_bundle":"https://pith.science/.well-known/pith/X4L55ZZH6SRUY5EKWA7O77C2AF/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:X4L55ZZH6SRUY5EKWA7O77C2AF","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":"0a4177315d428ce67b4de08a69000e63d0cccc608cd7cf158191e31823e3e978","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2019-03-14T11:56:31Z","title_canon_sha256":"0f189151d48595caba1229a4725327c1061d370187def2efc764c92af3d0d0f8"},"schema_version":"1.0","source":{"id":"1903.05928","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.05928","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"arxiv_version","alias_value":"1903.05928v2","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.05928","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_12","alias_value":"X4L55ZZH6SRU","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_16","alias_value":"X4L55ZZH6SRUY5EK","created_at":"2026-07-05T01:28:28Z"},{"alias_kind":"pith_short_8","alias_value":"X4L55ZZH","created_at":"2026-07-05T01:28:28Z"}],"graph_snapshots":[{"event_id":"sha256:998c45a7e0f431b44a8486bb4c2ee1639a9efff988e294fae39959e38fab26bb","target":"graph","created_at":"2026-07-05T01:28:28Z","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/1903.05928/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Distributed phased arrays based multiple-input multiple-output (DPA-MIMO) is a newly introduced architecture that enables both spatial multiplexing and beamforming while facilitating highly reconfigurable hardware implementation in millimeter-wave (mmWave) frequency bands. With a DPA-MIMO system, we focus on channel state information (CSI) acquisition and hybrid precoding. As benefited from a coordinated and open-loop pilot beam pattern design, all the sub-arrays can perform channel sounding with less training overhead compared with the traditional orthogonal operation of each sub-array. Furth","authors_text":"Dongming Wang, Xiaodai Dong, Xiaohu You, Yiming Huo, Yu Zhang","cross_cats":["math.IT"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2019-03-14T11:56:31Z","title":"Channel Estimation and Hybrid Precoding for Distributed Phased Arrays Based MIMO Wireless Communications"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.05928","kind":"arxiv","version":2},"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:b69212d597c124c877fe62bc7e341105cc77db4cfd537fb8bd2aa8d3e90a01bd","target":"record","created_at":"2026-07-05T01:28:28Z","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":"0a4177315d428ce67b4de08a69000e63d0cccc608cd7cf158191e31823e3e978","cross_cats_sorted":["math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.IT","submitted_at":"2019-03-14T11:56:31Z","title_canon_sha256":"0f189151d48595caba1229a4725327c1061d370187def2efc764c92af3d0d0f8"},"schema_version":"1.0","source":{"id":"1903.05928","kind":"arxiv","version":2}},"canonical_sha256":"bf17dee727f4a34c748ab03eeffc5a01638330b3f1f15533dff688707ffa13eb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"bf17dee727f4a34c748ab03eeffc5a01638330b3f1f15533dff688707ffa13eb","first_computed_at":"2026-07-05T01:28:28.144486Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T01:28:28.144486Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"DuYrn7U9gSxoIt/O16VBkqKlRd9ZsoJ83Bz9tbaGMGc9SC71joFK0fLF2n24TmXsG7sLuy2zJHvInzIkZ10mAQ==","signature_status":"signed_v1","signed_at":"2026-07-05T01:28:28.145001Z","signed_message":"canonical_sha256_bytes"},"source_id":"1903.05928","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b69212d597c124c877fe62bc7e341105cc77db4cfd537fb8bd2aa8d3e90a01bd","sha256:998c45a7e0f431b44a8486bb4c2ee1639a9efff988e294fae39959e38fab26bb"],"state_sha256":"309d4052da56647d6ae60a4b68d9bf7c76eac470b562a148315602943b5dd23c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"BzyWWkRqdljFLOh2//lVN1kusL2JIZ8DdeX38P4OKT0HwdxTrRlgK7hZJFQvwO+QHzFOtJCkprFor5Z0jnLuCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-17T07:35:32.634175Z","bundle_sha256":"7f637e2a1d721b38153ea2866efb5ca5d575d2e976228833a1996f3c0f76ada2"}}