Invalidity dossier
US 9357424
Efficient use of reference symbol resources in a hierarchical heterogeneous cell deployment
Current assignee: Telefonaktiebolaget LM Ericsson AB
Added 9/23/2026, 12:16:24 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US9357424B2
Title: "Efficient use of reference symbol resources in a hierarchical heterogeneous cell deployment"
Patent number / application: US9357424B2; Application US14/629,547; pre-grant publication US20150237520A1.
Assignee: Telefonaktiebolaget LM Ericsson AB (original assignee; also recorded as TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)).
Inventors: George Jöngren, Lars Lindbom, Stefan Parkvall.
Key dates (as listed): Priority date 2011-02-09; filing date 2015-02-24; publication of US20150237520A1 on 2015-08-20; grant/publication of US9357424B2 on 2016-05-31. Anticipated expiration listed as 2031-11-02. Legal status listed as Active (the source notes this status is an assumption, not a legal conclusion).
Purpose (per the description excerpt): The invention "relates generally to the control of devices in wireless communication networks, and more particularly relates to techniques for allocating and using reference signals in networks having heterogeneous cell deployments." The excerpt explains heterogeneous deployments—pico-cells within a macro-cell coverage area—and describes approaches to operating them: frequency separation between layers, and sharing radio resources via inter-cell interference coordination (ICIC), including resource splits over time, use of the X2 interface between base stations, and time synchronization requirements. LTE (Long-Term Evolution) is defined in the text's terminology list.
Plain-language scope from the supplied text: The patent concerns managing how reference symbols (pilot-type signals) are allocated and used when a network mixes large "macro" cells with smaller, lower-power nodes ("points") such as pico base stations, home base stations, and relays. Prior-art keywords given are csi (channel-state information), transmission points, resources, subset, and mobile station. Classifications include H04L5/0035 (resource allocation in a cooperative multipoint environment), H04L5/0051 (dedicated pilots destined for a single user/terminal), H04W24/10 (measurement reports), H04B7/024 (coordinated multipoint/MIMO), and H04W72/542 (scheduling based on measured or perceived quality).
Limitations of this excerpt: The supplied text is partial; it does not include the claims, abstract, or full description, so the exact claimed scope, limitations, and preferred embodiments are not established here. It also does not establish figures' content, any measurements or performance results, or the precise signaling details.
Source: https://patents.google.com/patent/[US9357424](/patent/US9357424)/en
Generated 10/1/2026, 9:53:43 PM
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Assignment history
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Prior art
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Derivative works
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