Invalidity dossier
US 5537410
Subsequent frame variable data rate indication method
Current assignee: ELECSYS Inc
Added 9/21/2026, 9:35:19 AM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,537,410
Title: Subsequent frame variable data rate indication method
Patent number: US 5,537,410 A
Application number: US 08/306,777
Inventor: Kaiping Li
Original assignee: Oki Telecom Inc.
Current assignee (as listed by the source): ELECSYS Inc; Canon Inc
Prior art date / filing date: 1994-09-15
Publication (grant) date: 1996-07-16
Legal status: Expired – Lifetime (anticipated expiration 2014-09-15), per the source's legal-status listing
Source: https://patents.google.com/patent/US5537410/en
Field and purpose. The patent relates generally to data communications, and more specifically to synchronous, fixed-boundary, variable-data-rate communication systems such as code division multiple access (CDMA) North American digital cellular telephone systems. In such systems, data rates can change at each frame boundary, so a receiver must determine the data rate of every frame before processing it. According to the excerpt, the conventional approach processes each frame separately at every possible data rate, including convolutional decoding, before deciding which rate was used — a source of wasted time and processing energy.
Plain-language scope. The described invention is a "subsequent frame" (or "next frame") variable data rate indication method: a transmitter inserts into the frame structure of a current frame an indication of the data rate of the next frame. The receiving station modem then learns each frame's data rate by analyzing information in the immediately preceding frame, so subsequent frame rates are known before processing, reducing processing load. Because the indication is embedded in the frame, it receives the same error protection as other frame information — stated to give high reliability with low overhead and complexity. The excerpt notes that with four possible rates, two bits suffice, and that the rate selection process is continually examined (e.g., frame quality indicators, symbol error rates), with fallback processing at remaining rates if checking fails.
What the excerpt does not establish. It does not identify claims, claim scope, or claim language; does not list or discuss prior-art references; and does not address litigation, validity, enforceability, or the accuracy of the listed assignments or legal status.
Generated 10/1/2026, 10:02:06 PM
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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
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