Invalidity dossier
US 5729571
Non-coherent digital receiver of a spread spectrum communication system
Current assignee: Samsung Electronics Co Ltd
Added 9/23/2026, 6:19:46 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,729,571 A
Title: Non-coherent digital receiver of a spread spectrum communication system
Assignee/Inventor: Original assignee Samsung Electronics Co., Ltd. (a Corp. of Korea); inventors Jong-Hyeon Park and Je-woo Kim. The excerpt lists the current assignee as [[Samsung Electronics Co Ltd](/litigations/by-plaintiff/Samsung%20Electronics%20Co%20Ltd).](/litigations/by-plaintiff/Samsung%20Electronics%20Co%20Ltd.)
Key dates (as listed): Priority date 1994-06-29; application No. US08/496,473 filed 1995-06-29; granted and published 1998-03-17. Status shown as "Expired – Fee Related," with anticipated expiration 2015-06-29. The source notes legal status and priority/publication dates are assumptions, not legal conclusions.
Purpose: The invention relates to a spread spectrum communication system using a pseudo-random noise (PN) code — specifically a digital receiver for demodulating received data into original data through digital processing, non-coherent detection, synchronization tracking, and initial synchronization of a received spread spectrum signal. The stated aim is to deliver error-free information in a noisy signal environment, where narrow-band modulation systems are weak and susceptible to multipath fading and narrow-band noise. The phase synchronization process is described as two steps: initial synchronization (finding a synchronous phase) and tracking the detected phase.
Plain-language scope: The receiver translates the spread spectrum signal into in-phase and quadrature-phase signals; a PN code generator produces a reference sequence comprising early, punctual, and late PN codes; a correlator unit correlates I and Q signals with that reference to produce early, punctual, and late correlation signals with I and Q components; an adaptive threshold control unit adaptively generates a variable threshold in response to the punctual PN code and the I/Q signals; and a synchronization detecting and tracking unit detects initial synchronization and phase difference between the received and reference PN code sequences, controlling PN code generation. Corresponding signals are squared, added, and square-rooted to compensate for the non-coherent effect. Correlators generally take correlation every data symbol. FIGS. 2A–2B show the inventive construction; FIGS. 3A–3B show synchronization detection states.
What the excerpt does not establish: It does not set out the full claims, the complete detailed description or omitted figures, any independent validity assessment, ownership transfers, litigation, or comparison against specific prior art beyond named technologies. It also does not establish legal status conclusively.
Generated 10/1/2026, 9:42:50 PM
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Assignment history
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Prior art
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