Invalidity dossier
US 7539463
Techniques to enhance diversity for a wireless system
Current assignee: Apple Inc
Added 9/23/2026, 11:13:05 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US7539463B2
Title: Techniques to enhance diversity for a wireless system
Patent number / application: US7539463B2; Application US11/095,207
Inventors: Nageen Himayat; Sumeet Sandhu
Original assignee: Intel Corp. Current assignee (as listed): Apple Inc.
Dates: Priority/filing date 2005-03-30; publication (grant) date 2009-05-26; legal status Active, with adjusted expiration listed as 2026-07-26. The source notes legal status and assignee listings are assumptions, not legal conclusions.
Purpose: The patent addresses limits on available spatial and frequency diversity in wireless systems and proposes techniques to improve spatial and/or frequency diversity to increase system performance. It situates the work in MIMO and multicarrier contexts: MIMO systems use multiple transmit/receive antennas and can transmit multiple data streams to provide spatial diversity, while multicarrier systems (e.g., OFDM, DMT) divide a channel into subcarriers and can interleave symbols across subcarriers for frequency diversity.
Plain-language scope (from the excerpt): The disclosed subject matter concerns transmitting a wireless signal using multiple antennas and multiple subcarriers, applying diversity across spatial streams and/or subcarrier blocks. Classification entries point to space-frequency diversity, space-frequency coding, transmit-side diversity with delayed versions of the same signal, differing channel coding between antennas, and interleaving under forward error control. The excerpt lists figures covering a system, a component, a "diversity architecture," a logic flow, two example diversity agents, and a graphical representation—but gives no figure text, claims, or detailed embodiments.
What the excerpt does not establish: It provides no claim language, no detailed description of the diversity agents or architecture, no specific algorithms, and no named prior-art references. Therefore no precise claim scope, novelty, or validity conclusion can be drawn from this material alone. Per instructions, no litigation, ownership-transfer, validity, or prior-art research is included.
Source: https://patents.google.com/patent/[US7539463](/patent/US7539463)/en
Generated 10/1/2026, 9:54:01 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.