Here's a concise summary of US Patent 10313077:

US Patent 10313077: Wireless communication method and wireless communication terminal for coexistence with legacy wireless communication terminal

• Title: Wireless communication method and wireless communication terminal for coexistence with legacy wireless communication terminal
• Assignee: Wilus Institute of Standards and Technology Inc.
• Inventors: Geonjung KO, Jinsam Kwak, Juhyung Son
• Filing Date: 2017-12-26
• Issue Date: 2019-06-04

Abstract:
A wireless communication terminal is disclosed for wireless communication. This terminal includes a transceiver and a processor. The processor is configured to transmit a non-legacy physical layer frame. This frame incorporates a legacy signaling field that contains information decipherable by an older, "legacy" wireless communication terminal, using the transceiver.

Plain-Language Overview of Independent Claims:

• Independent Claim 1 (Apparatus Claim): This claim describes a wireless communication device (terminal) that is designed to operate in an environment where both new ("non-legacy") and older ("legacy") wireless devices exist. The device has a transceiver for sending and receiving signals and a processor to handle communications. The processor is configured to receive a non-legacy data packet (physical layer frame) that includes a part understandable by legacy devices, called a "legacy signaling field." From this legacy field, the processor extracts "length information" indicating the total duration of the non-legacy frame. It also calculates additional information from a "remaining value" derived by dividing the length information by a standard data size (3 octets for a 6 Mbps legacy frame symbol). Finally, the processor uses a specific mathematical formula to determine the precise number of data symbols within the non-legacy physical layer frame.

• Independent Claim 9 (Method Claim): This claim outlines a method (a series of operational steps) for a wireless communication terminal to perform wireless communication. The method involves receiving a non-legacy physical layer frame that contains a legacy signaling field which can be decoded by a legacy wireless communication terminal. The method then proceeds to obtain "length information" from this legacy signaling field, which indicates the duration of the non-legacy physical layer frame. Subsequently, it involves obtaining other information by using a "remaining value" derived from dividing the length information by a specific data size (which is 3 octets for a legacy physical layer frame symbol at a 6 Mbps data rate). The final step is to determine the number of data symbols in the non-legacy physical layer frame using the same mathematical equation detailed in Claim 1.

Known litigation involving US patent 10313077 as of April 26, 2026, includes the following:

1. PTAB Case: IPR2025-01069

• Plaintiff(s) (Petitioner): [[Samsung Electronics Co Ltd](/litigations/by-plaintiff/Samsung%20Electronics%20Co%20Ltd).](/litigations/by-plaintiff/Samsung%20Electronics%20Co%20Ltd.)
• Defendant(s) (Patent Owner): Wilus Institute Of Standards & Technology Inc.
• Jurisdiction: Patent Trial and Appeal Board (PTAB).
• Case Number: IPR2025-01069.
• Filing Date: June 5, 2025.
• Current Status: Pending - Instituted.

2. US District Court Case: 2:24-cv-00753

• Jurisdiction: Texas Eastern District Court.
• Case Number: 2:24-cv-00753.
• Plaintiff(s): Not available from current search results.
• Defendant(s): Not available from current search results.
• Filing Date: Not explicitly available from current search results, but the case number implies a 2024 filing year.
• Current Status: Litigation.

3. US District Court Case: 2:24-cv-00752

• Jurisdiction: Texas Eastern District Court.
• Case Number: 2:24-cv-00752.
• Plaintiff(s): Not available from current search results.
• Defendant(s): Not available from current search results.
• Filing Date: Not explicitly available from current search results, but the case number implies a 2024 filing year.
• Current Status: Litigation.

4. US District Court Case: 2:24-cv-00746

• Jurisdiction: Texas Eastern District Court.
• Case Number: 2:24-cv-00746.
• Plaintiff(s): Not available from current search results.
• Defendant(s): Not available from current search results.
• Filing Date: Not explicitly available from current search results, but the case number implies a 2024 filing year.
• Current Status: Litigation.

Proceedings overview

There is currently one active Inter Partes Review (IPR) proceeding on US Patent 10,313,077, which has been instituted and is currently in the trial phase. This means that the patent's claims are actively being challenged, and no claims have been invalidated or sustained by a Final Written Decision yet, leaving the ultimate defensive posture uncertain.

IPR2025-01069 — [[[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) et al.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.%20et%20al.) v. Wilus Institute of Standards and Technology Inc.

• Type: Inter Partes Review
• Filed: 2025-06-05
• Status: Trial Instituted. The PTAB has decided to proceed with a trial on the merits of the challenges.
• Judge panel: The specific judge panel information for this IPR is not publicly available yet through the provided sources as of the latest update.
• Petition grounds: The petition was filed by Samsung Electronics Co., Ltd. et al. against claims of US10313077. The specific claims challenged, prior art references cited, and statutory bases (§ 102 for novelty and/or § 103 for obviousness) are typically detailed in the institution decision. This information is not explicitly provided in the initial prompt or readily available in a summary form without accessing the institution decision document.
• Institution decision: Instituted. The petition was granted a trial, indicating that Samsung Electronics Co., Ltd. et al. demonstrated a reasonable likelihood that at least one challenged claim is unpatentable. The institution decision would outline the specific claims and grounds for which trial was instituted. The exact date of institution is not provided in the prompt but occurred sometime before the "last modified" date of 2026-04-01.
• Final Written Decision: Not yet issued. The proceeding is still in the trial phase.
• Settlement / termination: No settlement or termination has been publicly reported; the IPR remains active.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This active IPR creates uncertainty regarding the validity of the challenged claims. A defendant facing assertion of this patent will need to monitor this proceeding closely, as an invalidation of claims would significantly weaken the patent owner's position. Conversely, if claims are sustained, it would strengthen the patent's validity against similar challenges.

Strategic summary

Currently, all claims of US 10,313,077 are "untested" by a final written decision from the PTAB. IPR2025-01069 is in the trial stage, meaning a decision on the merits of the challenged claims is pending. Until a Final Written Decision is issued, the full scope of which claims might be canceled or sustained remains unknown.

The estoppel landscape will only take effect after a Final Written Decision. If a Final Written Decision eventually issues and finds certain claims unpatentable, Samsung Electronics Co., Ltd. et al. (and their privies) would be estopped under § 315(e)(2) from asserting invalidity grounds they raised or reasonably could have raised in the IPR regarding those claims. For other potential defendants, the prior art grounds raised by Samsung in this IPR remain potentially available until a FWD is issued; however, they may be influenced by the outcome of this IPR.

Regarding pattern signals, only one IPR has been filed on this patent, and it is still active. Unified Patents, a defensive aggregator, is listed as having provided "Unified Patents PTAB Data" for this case, suggesting their involvement in tracking or potentially facilitating the challenge.

Recommended next steps

As IPR2025-01069 is active and instituted, a defendant should closely monitor the proceeding. Key upcoming milestones include the oral hearing (if requested) and, most importantly, the statutory one-year deadline for the Final Written Decision from the date of institution. While the exact institution date isn't provided in the prompt, the last modified date of 2026-04-01 indicates the trial is well underway. Accessing the publicly available documents for IPR2025-01069 on the USPTO PTAB E2E system (https://portal.unifiedpatents.com/ptab/case/IPR2025-01069) is crucial to determine the specific claims challenged, the prior art asserted, the institution decision date, and the PTAB's reasoning for instituting the trial. This information will inform any defensive strategy against US 10,313,077.

Inventors

• Geonjung KO (SK Telecom Co Ltd, Wilus Institute of Standards and Technology Inc.)
• Jinsam Kwak (SK Telecom Co Ltd, Wilus Institute of Standards and Technology Inc.)
• Juhyung Son (SK Telecom Co Ltd, Wilus Institute of Standards and Technology Inc.)

It is noted that all three inventors are listed with two affiliations (SK Telecom Co Ltd and Wilus Institute of Standards and Technology Inc.) at the time of filing, which suggests a collaborative effort or a transfer of employment/ IP rights occurred around the time of the invention. Generally, patent rights initially vest with the inventors, but are often assigned to the employer through employment agreements.

Original assignee

The entity named on the issued patent is SK Telecom Co Ltd and Wilus Institute of Standards and Technology Inc.

SK Telecom Co Ltd is a South Korean wireless telecommunications operator. It provides wireless voice and data transmission services, fixed-line telecommunication services (telephone, broadband internet, IPTV), and other businesses including IoT solutions. SK Telecom is an operating company, actively developing and deploying 5G core technologies and services. As of the current date, SK Telecom Co Ltd is an operating company.

Wilus Institute of Standards and Technology Inc. is a South Korea-based R&D company focused on developing next-generation wireless communications and multimedia technology standards, including 5G, Wi-Fi, and audio/video codecs. Wilus has made significant contributions to various standards bodies (e.g., 3GPP, IEEE 802.11, MPEG) and licenses its Standard Essential Patents (SEPs) through patent pools and bilateral agreements. They have also initiated litigation to enforce their Wi-Fi 6 SEPs. Wilus appears to be an operating R&D and licensing company.

Assignment timeline

• 2017-12-26 (executed) / recorded 2017-12-26 — Reel 043006/0598
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: KO, GEONJUNG; KWAK, JINSAM; SON, JUHYUNG
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GA RYONG RO, SEOCHO-GU, SEOUL, KOREA (REPUBLIC OF)
  • Context: Transfer of inventor's interest to a co-applicant/assignee.
• 2017-12-26 (executed) / recorded 2017-12-26 — Reel 043006/0598
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: SK TELECOM CO LTD
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GA RYONG RO, SEOCHO-GU, SEOUL, KOREA (REPUBLIC OF). This correspondent recurs in this chain.
  • Context: Transfer of original assignee's interest to a co-applicant/assignee.
• 2018-07-18 (executed) / recorded 2018-07-18 — Reel 044033/0849
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC., SK TELECOM CO., LTD.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GARYONG-RO, SEOCHO-GU, SEOUL, 06634 KOREA (REPUBLIC OF). This correspondent recurs in this chain.
  • Context: Reassignment to include SK Telecom Co., Ltd. as a co-assignee.
• 2022-12-18 (executed) / recorded 2022-12-19 — Reel 062152/0001
  • Conveyance: LICENSE
  • Assignor: SK TELECOM CO., LTD.
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GARYONG-RO, SEOCHO-GU, SEOUL, 06634 KOREA (REPUBLIC OF). This correspondent recurs in this chain.
  • Context: Exclusive license granted by SK Telecom to Wilus.
• 2024-06-20 (executed) / recorded 2024-06-20 — Reel 067098/0609
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: SK TELECOM CO., LTD.
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GARYONG-RO, SEOCHO-GU, SEOUL, 06634 KOREA (REPUBLIC OF). This correspondent recurs in this chain.
  • Context: Transfer of SK Telecom's interest to Wilus.
• 2020-08-31 (executed) / recorded 2025-02-26 — Reel 068695/0001
  • Conveyance: CORRECTIVE ASSIGNMENT
  • Assignor: SK TELECOM CO., LTD.
  • Assignee: WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC.
  • Correspondent: BAE, KIM & LEE IP, 11TH FLOOR, SOUTH BLDG., CENTERVILLE, 115, GARYONG-RO, SEOCHO-GU, SEOUL, 06634 KOREA (REPUBLIC OF). This correspondent recurs in this chain.
  • Context: Corrective assignment to amend agreement date of an exclusive license.

Timeline diagram

timeline
    title Ownership of US 10313077
    2015 : Priority date
    2017 : Application filed
         : Inventors assign to Wilus
         : SKT assigns to Wilus
    2018 : Wilus assigns to Wilus, SKT
    2019 : Patent granted
    2022 : SKT licenses to Wilus
    2024 : SKT assigns to Wilus
    2025 : Corrective assignment re: license

NPE / troll-pattern signals

1. Shell-entity transfer — not present. Both SK Telecom and Wilus Institute of Standards and Technology Inc. are identifiable operating companies with active R&D and product/licensing activities.
2. Known asserter in the chain — present. Wilus Institute of Standards and Technology Inc. has engaged in patent assertion, including initiating litigation in the Eastern District of Texas against companies like ASUS, HP, and Samsung for Wi-Fi 6 SEP infringement. Unified Patents has also filed challenges against Wilus's Wi-Fi patents.
3. Repeat correspondent across the chain — present. BAE, KIM & LEE IP is the correspondent of record for all recorded assignments related to this patent (Reel 043006/0598, Reel 044033/0849, Reel 062152/0001, Reel 067098/0609, Reel 068695/0001).
4. Cascading transfers — not present. The transfers, while multiple, are spread out over several years and primarily involve the two original entities, not a rapid succession of different LLCs.
5. Pre-litigation transfer — unclear. While Wilus has initiated litigation in 2024, the assignments involving SK Telecom to Wilus happened in 2022 and 2024, which could be related to preparing for assertion, but there isn't a tight "within 6 months" window to the initial suits on this specific patent.
6. Bankruptcy fire-sale — not present. There is no indication that either SK Telecom Co Ltd or Wilus Institute of Standards and Technology Inc. has undergone bankruptcy proceedings.
7. Privateering — unclear. While Wilus asserts patents and SK Telecom is an operating company, there's no public evidence to suggest that SK Telecom is using Wilus to assert patents on its behalf against competitors in a privateering arrangement.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at a known defensive aggregator.

Verdict

NPE — moderate confidence. Wilus Institute of Standards and Technology Inc., the current assignee, is identified as a patent asserter that actively licenses and litigates its SEP portfolio, as evidenced by its lawsuits against ASUS, HP, and Samsung for Wi-Fi 6 SEP infringement, and challenges by Unified Patents. The consistent use of the same correspondent firm, BAE, KIM & LEE IP, across multiple assignments further supports a pattern often associated with NPEs.

USPTO Assignment Center search for US10313077: https://assignmentcenter.uspto.gov/#!/assignment-view/US10313077/1

To identify the most relevant prior art for US patent 10313077, I need to search the USPTO database for the patent and examine its cited references. I will then analyze each cited patent for its publication/filing date, a brief description, and which claims of US10313077 it might anticipate under 35 U.S.C. § 102.

Unfortunately, I cannot directly access or search the USPTO database in real-time to retrieve the full list of cited prior art for US10313077 and then analyze each one in detail. The provided search results mention "Patent Public Search" as a tool, but I don't have the capability to interact with it in that manner to extract all the specific citations and their content.

Therefore, I cannot provide a detailed analysis of the most relevant prior art for US patent 10313077 at this time. To do so would require access to the patent document itself and its complete list of references, along with the ability to review each referenced document.

Due to the absence of specific prior art references within the provided patent text or through the executed searches, a comprehensive obviousness analysis of US Patent 10313077 under 35 U.S.C. § 103 cannot be performed at this time.

To conduct such an analysis, it is necessary to identify concrete prior art documents (e.g., other patents, publications) that predate the patent's priority date (June 29, 2015). With these specific references, an analyst would then:

1. Delineate the scope and content of the prior art. This involves understanding what each prior art reference discloses.
2. Identify the differences between the claimed invention and the prior art. This pinpoints what aspects of the patent's claims are not explicitly taught by individual prior art references.
3. Determine the level of ordinary skill in the art. For US10313077, this would generally pertain to wireless communication engineers or experts working with IEEE 802.11 standards.
4. Ascertain whether the differences would have been obvious to a person having ordinary skill in the art (POSITA) at the time of the invention. This crucial step involves identifying a "teaching, suggestion, or motivation" (TSM) in the prior art that would have led a POSITA to combine the references to arrive at the claimed invention, with a reasonable expectation of success. This could be explicit suggestions, implicit motivations from the nature of the problem, or common knowledge in the field.

Without the actual list of cited prior art, it is impossible to identify specific combinations or articulate the motivations that would render the claims of US10313077 obvious.

Patent Term Adjustments (PTA) and Patent Term Extensions (PTE)

The provided patent text and search results do not explicitly state any Patent Term Adjustments (PTA) or Patent Term Extensions (PTE) for US Patent 10313077.

Patent Term Adjustment (PTA) is an extension to the patent term granted to compensate for certain delays caused by the USPTO during the prosecution of a utility or plant patent application. This was established by the American Inventors Protection Act of 1999 for applications filed on or after May 29, 2000. Delays typically fall into categories such as the USPTO failing to: issue a first office action within 14 months, respond to an applicant's reply within 4 months, issue a patent within 4 months of the issue fee payment, or issue a patent within 36 months from the filing date. However, any accrued PTA can be reduced if delays are caused by the applicant.

Patent Term Extension (PTE), under 35 U.S.C. § 156, is typically related to delays in the regulatory review process for products, most commonly pharmaceutical products, by agencies like the FDA. This extension is limited to a single patent covering the product and can be up to five years, but not beyond 14 years after FDA approval.

Since there's no mention of a pharmaceutical product or FDA approval in the patent text or search results, it's highly unlikely that US10313077 would be eligible for PTE. To definitively confirm PTA, access to the USPTO's Patent Center for this specific patent would be required, as PTA is calculated and recorded by the USPTO during prosecution.

Continuation, Divisional, and Related Family Members

US Patent 10313077 is identified as a continuation of International Patent Application No. PCT/KR2016/006976, filed on June 29, 2016. The international application claims priority to:

• Korean Patent Application No. 10-2015-0092525, filed on June 29, 2015.
• Korean Patent Application No. 10-2015-0117434, filed on August 20, 2015.

The patent also lists other versions/family members:

• US20180123757A1 (publication of the US application).

Additionally, the Google Patents page for US10313077 indicates priority claims to:

• US16/396,635 (which resulted in US10651992B2), prioritized on April 27, 2019.
• US16/835,305 (which resulted in US11128421B2), prioritized on March 31, 2020.
• US17/408,296 (which resulted in US11700084B2), prioritized on August 20, 2021.
• US18/206,081 (which resulted in US12149354B2), prioritized on June 6, 2023.
• US18/913,806 (which resulted in US20250119240A1), prioritized on October 11, 2024.

A continuation application is a second application for the same invention disclosed in a prior, co-pending parent application, without introducing new subject matter, and aims to pursue additional claims or different claim scope. A divisional application also shares the same disclosure and priority date as the parent but is filed when the USPTO determines that the parent application contains claims directed to multiple inventions, requiring the applicant to restrict the claims in the parent. There is no explicit mention of divisional applications in the provided text.

Projected Expiration Date

The statutory patent term for U.S. patents filed on or after June 8, 1995, is 20 years from the earliest filing date of the application or any application for which a benefit is claimed under 35 U.S.C. §§ 120, 121, or 365(c).

US Patent 10313077 claims priority to Korean Patent Application No. 10-2015-0092525, filed on June 29, 2015.

Therefore, the anticipated expiration date for US Patent 10313077, absent any patent term adjustments or extensions, would be June 29, 2035.

The Google Patents page for US10313077 lists an "Anticipated expiration" date of 2036-06-29. This suggests that there might be a patent term adjustment (PTA) of approximately one year, or a different earliest priority date being considered for the patent term calculation. Without access to the official USPTO patent prosecution history for US10313077, the exact reason for this discrepancy cannot be definitively determined.

Defensive Disclosure Document for US Patent 10,313,077

This document outlines various derivative concepts and potential prior art combinations related to US Patent 10,313,077, titled "Wireless communication method and wireless communication terminal for coexistence with legacy wireless communication terminal." The objective is to proactively define and disclose modifications and applications that could render future incremental improvements in this domain obvious or non-novel, thereby establishing defensive prior art.

Analysis of Core Claims

The core of US Patent 10,313,077 revolves around enabling efficient coexistence between non-legacy and legacy wireless communication terminals, particularly within IEEE 802.11 environments. This is achieved by embedding length information (decodable by legacy terminals) in a non-legacy physical layer frame's legacy signaling field (L-SIG) and extracting additional non-legacy specific information from the remaining value of the length information, as well as by using specific modulation patterns and symbols for auto-detection.

Independent Claim 1 (Apparatus) and Independent Claim 9 (Method)

Both independent claims focus on a wireless communication terminal (Claim 1) or an operation method thereof (Claim 9) that receives a non-legacy physical layer frame, obtains a legacy signaling field and its length information, extracts additional information from a "remaining value" derived from the length information, and uses a specific equation to determine the number of data symbols in the non-legacy frame. The PE Disambiguity field is also highlighted as being set based on symbol durations and duration increments.

The derivatives below apply to the fundamental mechanism of encoding/decoding coexistence information within a shared physical layer structure, and the logic of deriving non-legacy frame parameters from legacy-interpretable fields.

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Derivative Variations

1. Material & Component Substitution

Derivative 1.1: Reconfigurable Intelligent Surface (RIS) Integrated Transceiver

Enabling Description:
A wireless communication terminal integrates a reconfigurable intelligent surface (RIS) with its transceiver and processor. The RIS dynamically alters the propagation environment to enhance signal quality or steer beams. The processor, in conjunction with the RIS control unit, adjusts the power spectral density (PSD) of the L-SIG and subsequent HE-SIG fields to ensure reliable reception by legacy terminals within the RIS-modified coverage area, while simultaneously encoding additional non-legacy configuration bits into unused subcarriers or phase shifts of the L-SIG pilot tones. For instance, the 'm' parameter in the N_SYM calculation could be dynamically adjusted based on RIS configuration, signaling optimal subcarrier allocation or spatial stream mapping. The RIS elements themselves could be composed of liquid crystal metamaterials, offering agile reconfigurability at sub-millisecond latencies. The processor would use an embedded field-programmable gate array (FPGA) to implement real-time RIS control and the complex decoding logic for the modified L-SIG/HE-SIG.

graph TD
    A[Non-Legacy Terminal] --> B{Transceiver};
    B --> C[RIS Control Unit];
    C --> D[Reconfigurable Intelligent Surface];
    D -- Modified Channel --> E[Legacy Terminal];
    B -- L-SIG/HE-SIG TX --> F[Legacy/Non-Legacy Receiver];
    F --> G[Processor (FPGA-based)];
    G -- Decodes L-LENGTH, m, b_PE_Disambiguity --> H[Determine N_SYM];
    C -- RIS State Info --> G;

Derivative 1.2: GaN-based Millimeter-Wave Transceiver with Optical Interconnect

Enabling Description:
The wireless communication terminal employs Gallium Nitride (GaN) high-electron-mobility transistors (HEMTs) in its millimeter-wave (mmWave) transceiver front-end to achieve high power efficiency and linearity at frequencies above 60 GHz. This allows for very high data rates in the non-legacy physical layer frame. Data paths within the terminal, including between the transceiver and the processor, utilize optical interconnects (e.g., silicon photonics) to reduce latency and electromagnetic interference, critical for precise timing synchronization and rapid preamble processing in mmWave scenarios. The processor, implemented as a custom Application-Specific Integrated Circuit (ASIC) with integrated digital signal processors (DSPs), handles the extremely fast symbol rates and the complex algorithms for deriving N_SYM from the L-LENGTH, including adapting the T_HE_PREAMBLE and T_SYM values based on the specific mmWave numerology and channel bandwidth. The fixed 3 octet legacy data size assumption (from 6 Mbps legacy frame) would be re-interpreted as a scaling factor for mmWave equivalent legacy bandwidth.

graph TD
    A[Non-Legacy Terminal] --> B(GaN mmWave Transceiver);
    B -- Optical Interconnect --> C[ASIC Processor w/ DSPs];
    C -- High-Speed Decoding --> D{Extract L-LENGTH};
    D --> E{Calculate Remaining Value};
    E --> F{Determine N_SYM via Equation};
    B -- TX/RX mmWave Frames --> G[Wireless Medium];
    G -- Coexistence --> H[Legacy/Non-Legacy Terminals];

Derivative 1.3: Ferroelectric RAM (FeRAM) Assisted Processor for Dynamic Parameter Storage

Enabling Description:
A low-power wireless communication terminal utilizes a processor augmented with integrated ferroelectric RAM (FeRAM) for non-volatile, high-speed storage of dynamic communication parameters. This FeRAM stores frequently updated values such as T_HE_PREAMBLE and T_SYM for various operating modes, as well as previously observed b_PE_Disambiguity values and corresponding channel conditions. This allows for rapid recall and application of these parameters without relying on slower flash memory or re-calculation, thereby accelerating the determination of N_SYM and the overall frame decoding process upon receiving the L-SIG. The FeRAM's low-power consumption is particularly advantageous for battery-operated IoT devices that need to quickly switch between legacy-compatible listening modes and non-legacy reception.

graph TD
    A[Non-Legacy Terminal] --> B[Low-Power Processor];
    B -- Read/Write --> C[Integrated FeRAM];
    C -- Stores Parameters --> D{T_HE_PREAMBLE, T_SYM, b_PE_Disambiguity Cache};
    B -- Receives L-SIG --> E[Decoding Module];
    E -- Accesses C --> F{Calculate N_SYM};
    F --> G[Frame Processing];

Derivative 1.4: Photonic Crystal Antenna Array with Software-Defined Radio (SDR)

Enabling Description:
The wireless communication terminal incorporates a photonic crystal antenna array for highly directional beamforming and multi-band operation, controlled by a software-defined radio (SDR) unit. The SDR reconfigures the antenna characteristics and the baseband processing chain in real-time. This enables the transceiver to synthesize arbitrary L-SIG signal characteristics for enhanced information encoding beyond standard BPSK/QBPSK, such as specific subcarrier phase rotations or amplitude shifts on non-pilot subcarriers within the L-SIG, while maintaining legacy decodability through the dominant signal components. The processor, integrated within the SDR, dynamically adjusts the decoding algorithm for the L_LENGTH and the 'remaining value' extraction based on the current SDR configuration and photonic antenna state, effectively using the fine-grained signal modifications within the L-SIG as an additional data channel for m or b_PE_Disambiguity or other non-legacy signaling field format indicators.

graph TD
    A[Non-Legacy Terminal] --> B[SDR Unit];
    B -- Control Signals --> C[Photonic Crystal Antenna Array];
    C -- Dynamic Beamforming --> D[Wireless Medium];
    B -- Programmable DSP --> E[Processor];
    E -- L-SIG/HE-SIG Processing --> F{Adaptive Decoding Logic};
    F -- N_SYM Calculation --> G[Frame Recovery];

Derivative 1.5: Graphene-based Terahertz Transceiver

Enabling Description:
A next-generation wireless communication terminal employs a graphene-based terahertz (THz) transceiver for ultra-high bandwidth, short-range communication. Graphene's exceptional electronic and optical properties allow for compact, high-frequency antenna structures and rapid modulation. The processor, comprising specialized THz signal processing units, is configured to receive non-legacy physical layer frames transmitted at THz frequencies. The legacy signaling field (L-SIG equivalent, perhaps a scaled-down version or a specific THz control burst) would still convey fundamental length information in a format decodable by simpler THz legacy devices (e.g., early THz communication standards). The processor would then extract the L_LENGTH and calculate the remaining value against a THz-specific legacy data size (e.g., 3 femto-octets for a 6 Tbps legacy THz frame symbol). The N_SYM equation would be adapted with T_HE_PREAMBLE and T_SYM values appropriate for femtosecond-duration THz symbols. The PE Disambiguity field would be interpreted in the context of THz pulse shaping and propagation characteristics.

graph TD
    A[Non-Legacy Terminal] --> B(Graphene THz Transceiver);
    B -- THz Pulses --> C[Wireless Medium (Short-Range)];
    B -- THz Signal Processing --> D[Processor (THz SPUs)];
    D -- Decodes THz L-SIG --> E{Extract THz L-LENGTH};
    E --> F{Calculate THz Remaining Value};
    F --> G{Determine N_SYM (THz) via Equation};
    G --> H[THz Frame Processing];

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2. Operational Parameter Expansion

Derivative 2.1: Ultra-Low-Power Wide Area Network (LPWAN) Coexistence

Enabling Description:
The wireless communication method is adapted for LPWAN scenarios, where non-legacy nodes (e.g., future 802.11ah derivatives) coexist with legacy 802.11 devices in unlicensed bands. The non-legacy physical layer frame would be significantly longer in duration (e.g., hundreds of milliseconds to seconds) due to lower data rates and higher coding gains. The L_LENGTH field, typically expressed in microseconds, would be reinterpreted as indicating a multiple of a much larger time unit (e.g., 100 microseconds or 1 millisecond per unit). The m value and b_PE_Disambiguity would be designed to compensate for the significant difference in symbol durations between the legacy (e.g., 4 µs) and LPWAN non-legacy (e.g., 320 µs) symbols, allowing for correct N_SYM calculation for extended LPWAN packets. The data size transmittable by a legacy symbol (3 octets for 6 Mbps) would be scaled down proportionally for the LPWAN context, while maintaining the same arithmetic for the remaining value calculation.

graph TD
    A[LPWAN Non-Legacy Node] --> B{Transmit LPWAN Frame};
    B -- Includes Scaled L-SIG --> C[Legacy 802.11 Terminal];
    C -- Decodes Scaled L-LENGTH --> D[Defers Access];
    B -- LPWAN Preamble (Longer T_HE_PREAMBLE) --> E[LPWAN Non-Legacy Receiver];
    E -- Extracts Scaled L-LENGTH --> F{Calculates N_SYM (LPWAN)};
    F --> G[Decodes LPWAN Data];
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#ccf,stroke:#333,stroke-width:2px

Derivative 2.2: Extreme High-Density Multi-User Environment

Enabling Description:
In an environment with extremely high density of co-located non-legacy and legacy wireless communication terminals (e.g., stadium, concert venue, dense urban IoT deployment), the non-legacy physical layer frame is highly optimized for multi-user (MU) MIMO and Orthogonal Frequency Division Multiple Access (OFDMA). The b_PE_Disambiguity field or an extended 'remaining value' is used to signal the number of concurrent users, OFDMA resource unit (RU) allocation, and MU-MIMO stream assignments. The T_HE_PREAMBLE is made highly compact, and T_SYM is varied dynamically across users or RUs. The specific equation for N_SYM would be executed per-user, with T_SYM being specific to that user's assigned modulation and coding scheme (MCS) and RU size. The m value could also encode a pointer to a pre-defined MU-MIMO configuration table.

graph TD
    A[Non-Legacy AP] --> B{Transmit High-Density Frame};
    B -- L-SIG/HE-SIG --> C[Legacy/Non-Legacy Terminals (Dense)];
    C -- Non-Legacy Decodes --> D{Extract L-LENGTH};
    D --> E{Calculate Remaining Value (incl. MU-MIMO/OFDMA info)};
    E --> F{Determine N_SYM (Per User) via Equation};
    F --> G[Per-User Data Decoding];
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#ccf,stroke:#333,stroke-width:2px

Derivative 2.3: Underwater Acoustic Communication

Enabling Description:
The coexistence method is adapted for underwater acoustic communication, where legacy sonar or basic acoustic modems coexist with advanced acoustic communication systems. The "physical layer frame" becomes an acoustic burst. The "legacy signaling field" would be an initial acoustic pulse sequence decodable by simple hydrophones, conveying a basic "length information" (e.g., duration of the entire acoustic transmission in milliseconds). The data size transmittable by a "symbol of a legacy acoustic physical layer frame" would be defined for a low-rate acoustic modulation scheme. The non-legacy acoustic frame would use complex modulations (e.g., OFDM with dynamic subcarrier allocation). The 'remaining value' from the length information, combined with a 'PE Disambiguity field' embedded in the non-legacy acoustic preamble, would inform the advanced receiver about the specific acoustic data symbol duration (T_SYM) and preamble structure (T_HE_PREAMBLE) used in the non-legacy part of the acoustic burst. The N_SYM equation would then calculate the number of acoustic data symbols.

graph TD
    A[Acoustic Transmitter] --> B{Transmit Acoustic Burst};
    B -- Legacy Acoustic Pulse --> C[Legacy Hydrophone/Modem];
    C -- Decodes Duration --> D[Acoustic Channel Clear];
    B -- Non-Legacy Acoustic Preamble/Data --> E[Advanced Acoustic Receiver];
    E -- Extracts L-LENGTH (Acoustic) --> F{Calculates Remaining Value (Acoustic)};
    F --> G{Determines N_SYM (Acoustic) via Equation};
    G --> H[Decodes Acoustic Data];
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#ccf,stroke:#333,stroke-width:2px

Derivative 2.4: Quantum Communication Link with Classical Control Channel

Enabling Description:
In a quantum communication system, where quantum states are transmitted for secure key distribution or quantum entanglement, a classical wireless control channel (e.g., a low-power 802.11 variant) coexists with a non-legacy quantum state transmission channel. The wireless communication terminal manages this hybrid link. The legacy signaling field in a classical wireless frame would convey the duration of a specific quantum transmission sequence to classical receivers, allowing them to defer. The processor, responsible for managing the quantum link, would utilize this L_LENGTH and derive N_SYM for the classical control data that might be multiplexed within the classical frame to coordinate quantum operations. The 'remaining value' and b_PE_Disambiguity could encode quantum channel parameters (e.g., qubit encoding scheme, error correction type) or the actual duration of the quantum part of the frame, which is signaled indirectly via the classical L-SIG.

graph TD
    A[Quantum Transmitter] --> B{Classical Wireless Control Frame};
    B -- L-SIG --> C[Legacy Classical Receiver];
    C -- Decodes L-LENGTH --> D[Defers Classical Access];
    B -- Non-Legacy HE-SIG (Classical) --> E[Quantum Receiver (Classical Processor)];
    E -- Extracts L-LENGTH, m, b_PE_Disambiguity --> F{Determine N_SYM (Classical) via Equation};
    F --> G[Classical Control Data for Quantum Link];
    A -- Quantum Channel --> H[Quantum Receiver (Qubit Processor)];
    G -- Coordinate --> H;

Derivative 2.5: High-Frequency Trading (HFT) Network with Coexisting Protocols

Enabling Description:
The wireless communication method is applied to high-frequency trading (HFT) networks operating on dedicated, low-latency wireless links (e.g., microwave, millimeter-wave point-to-point). Legacy trading systems might use older, slightly slower wireless protocols, while non-legacy systems demand microsecond-level latency and custom high-speed framing. The non-legacy physical layer frame, containing HFT data, would transmit a very short "legacy signaling field" to alert the older systems. The L_LENGTH would be interpreted with extreme precision (e.g., nanoseconds per unit), and the 'remaining value' and b_PE_Disambiguity would be utilized to encode extremely fine-grained timing information (e.g., sub-nanosecond synchronization offsets) for the non-legacy HFT data symbols. The N_SYM equation would calculate the number of HFT-specific data symbols, which might be extremely large due to the short symbol durations (T_SYM) in such ultra-low-latency environments.

graph TD
    A[HFT Non-Legacy Terminal] --> B{Transmit Ultra-Low-Latency Frame};
    B -- Short L-SIG (precise duration) --> C[Legacy HFT System];
    C -- Decodes L-LENGTH (ns) --> D[Defers Access (Critical)];
    B -- Non-Legacy HE-SIG (HFT) --> E[HFT Non-Legacy Receiver];
    E -- Extracts L-LENGTH, m, b_PE_Disambiguity --> F{Determine N_SYM (HFT) via Equation};
    F --> G[Process HFT Data (Microsecond Precision)];

---

3. Cross-Domain Application

Derivative 3.1: Autonomous Vehicle Platooning (Automotive)

Enabling Description:
In an autonomous vehicle platooning system, a lead vehicle transmits a non-legacy physical layer frame (e.g., V2X communication based on IEEE 802.11bd or newer). This frame includes a legacy signaling field (e.g., an older 802.11p-compatible message) that indicates the total duration of the platooning data burst. This allows older, non-platooning-capable vehicles or roadside units (RSUs) to detect the channel occupation and avoid interference. The following autonomous vehicles, acting as non-legacy terminals, receive this frame. Their processors obtain the L_LENGTH from the legacy field and extract additional platooning-specific information (e.g., platoon size, inter-vehicle distance parameters, lane change intent) from the 'remaining value' or b_PE_Disambiguity of the length information. The N_SYM equation calculates the number of non-legacy platooning data symbols, allowing precise synchronization and data decoding for cooperative driving maneuvers.

sequenceDiagram
    Lead_Vehicle->>Platoon_Vehicle: Transmit V2X Frame (L-SIG + HE-SIG + Data)
    Platoon_Vehicle->>Platoon_Vehicle: Receive V2X Frame
    Platoon_Vehicle->>Processor: Obtain L-SIG, L-LENGTH
    Processor->>Processor: Calculate Remaining Value (Platooning Info)
    Processor->>Processor: Determine N_SYM (Platooning Data)
    Processor->>Platoon_Vehicle: Decode Platooning Data
    Platoon_Vehicle->>Other_Vehicles: Cooperative Driving Actions
    Lead_Vehicle->>Legacy_Vehicle: Transmit V2X Frame (L-SIG)
    Legacy_Vehicle->>Legacy_Vehicle: Decode L-LENGTH
    Legacy_Vehicle->>Legacy_Vehicle: Defer Channel Access (Collision Avoidance)

Derivative 3.2: Precision Agriculture (AgriTech)

Enabling Description:
In a precision agriculture system, a central base station (or a lead autonomous tractor) transmits non-legacy physical layer frames containing high-resolution sensor data (soil moisture, nutrient levels, drone imagery) or control commands for robotic farm equipment. These frames include a legacy signaling field (e.g., compatible with older industrial Wi-Fi or proprietary agricultural telemetry systems) conveying the overall transmission duration. This allows older farm equipment or legacy IoT sensors to defer their transmissions. Newer, non-legacy robotic equipment (e.g., autonomous sprayers, harvesters) acting as wireless communication terminals receive these frames. Their processors obtain the L_LENGTH and use the 'remaining value' or b_PE_Disambiguity to decode specific agricultural parameters, such as the type of crop treatment, the spatial coordinates for targeted irrigation, or sensor calibration data. The N_SYM equation determines the count of non-legacy data symbols, enabling efficient and precise execution of farming tasks.

graph LR
    BS[Agricultural Base Station] -- Transmit Non-Legacy Frame --> A(Legacy Farm Sensor);
    BS -- Transmit Non-Legacy Frame --> B(Non-Legacy Robotic Sprayer);
    A -- Decodes L-LENGTH --> C{Defer Transmission};
    B -- Obtain L-SIG --> D{Extract L-LENGTH};
    D -- Calculate Remaining Value (Agri-specific Info) --> E{Determine N_SYM (Agri-Data)};
    E --> F[Decode Agri-Data & Execute Task];

Derivative 3.3: Smart City Infrastructure Management (Urban Planning)

Enabling Description:
Within a smart city infrastructure, intelligent traffic lights, environmental sensors, and public safety cameras form a heterogeneous wireless network. A central city management node or a smart traffic intersection controller transmits non-legacy physical layer frames containing real-time traffic flow optimization data, emergency alerts, or sensor aggregation requests. These frames incorporate a legacy signaling field that older, simpler city sensors or legacy public Wi-Fi access points can decode to understand the channel occupation. Non-legacy smart sensors or autonomous utility vehicles receive these frames. Their processors obtain the L_LENGTH from the legacy field and extract fine-grained city management information (e.g., precise timing for traffic signal phase changes, specific environmental anomaly thresholds, geo-fencing coordinates for public safety drone patrols) from the 'remaining value' or b_PE_Disambiguity. The N_SYM equation calculates the number of non-legacy urban data symbols, facilitating dynamic and responsive city management.

stateDiagram
    state "Start Transmission" as TX_START
    state "Legacy L-SIG Generation" as L_SIG_GEN
    state "Encode Length Information" as ENC_LEN_INFO
    state "Encode Remaining Value (City Data)" as ENC_REM_VAL
    state "Non-Legacy HE-SIG/Data Generation" as HE_DATA_GEN
    state "Transmit Frame" as TX_FRAME

    state "Receive Frame" as RX_FRAME
    state "Legacy Decoding" as LEG_DEC
    state "Non-Legacy Decoding" as NON_LEG_DEC
    state "Extract L-LENGTH" as EXT_LEN
    state "Calculate Remaining Value (City Data)" as CALC_REM_VAL
    state "Determine N_SYM (City Data)" as DET_N_SYM
    state "Process City Data" as PROC_CITY_DATA

    TX_START --> L_SIG_GEN : Initiate Non-Legacy Frame
    L_SIG_GEN --> ENC_LEN_INFO : Basic Frame Duration
    ENC_LEN_INFO --> ENC_REM_VAL : City-Specific Parameters
    ENC_REM_VAL --> HE_DATA_GEN : Full Frame Construction
    HE_DATA_GEN --> TX_FRAME : Send
    TX_FRAME --> RX_FRAME : Over Wireless Medium

    RX_FRAME --> LEG_DEC : Legacy Terminal path
    LEG_DEC --> EXT_LEN : Legacy L-LENGTH decode
    EXT_LEN --> LEG_DEC_COMPLETE : Defer or basic action
    
    RX_FRAME --> NON_LEG_DEC : Non-Legacy Terminal path
    NON_LEG_DEC --> EXT_LEN : Non-Legacy L-LENGTH decode
    EXT_LEN --> CALC_REM_VAL : Decode City Data from Remaining Value
    CALC_REM_VAL --> DET_N_SYM : Calculate Number of Symbols
    DET_N_SYM --> PROC_CITY_DATA : Utilize City Data

---

4. Integration with Emerging Tech

Derivative 4.1: AI-Driven Adaptive L-SIG Encoding/Decoding

Enabling Description:
The wireless communication terminal's processor is augmented with an embedded Artificial Intelligence (AI) module, specifically a deep reinforcement learning agent. This AI continuously monitors channel conditions, detected legacy traffic patterns, and the performance of L_LENGTH interpretation by various legacy devices in the vicinity. Based on this real-time data, the AI module dynamically optimizes the encoding of the 'remaining value' within the L-SIG and the b_PE_Disambiguity field. For instance, in noisy environments, it might select a more robust encoding scheme for the 'remaining value' (e.g., BPSK on specific subcarriers, even if it reduces the amount of information) or dynamically adjust m to provide clearer disambiguation. Conversely, in clean channels, it might maximize information density. The AI also adaptively tunes the receiver's decoding thresholds and parameters for N_SYM calculation, learning from past successful and failed decodes to improve robustness and speed.

graph TD
    A[Wireless Terminal] --> B{Transceiver};
    B -- RX/TX Frames --> C[Processor w/ AI Module];
    C -- Feedback (Channel, Legacy Activity) --> D(Reinforcement Learning Agent);
    D -- Optimized Encoding/Decoding Params --> C;
    C -- Encodes L-SIG/HE-SIG --> E[L-SIG Encoder];
    E -- Decodes L-LENGTH, m, b_PE_Disambiguity --> F[N_SYM Calculator];
    F --> G[Frame Management];

Derivative 4.2: IoT Sensor Network with Real-time Channel Monitoring

Enabling Description:
In a large-scale Internet of Things (IoT) sensor network, each non-legacy IoT gateway or sensor node incorporates local IoT sensors for real-time channel monitoring (e.g., spectrum occupancy, interference levels, received signal strength of legacy beacons). The raw data from these IoT sensors is fed into the communication terminal's processor. This processor uses the real-time monitoring data to infer the presence and activity of legacy devices. It can then dynamically adjust the 'increment of duration' when setting the L_LENGTH value in its transmitted non-legacy physical layer frames, ensuring that legacy devices accurately defer for the correct duration, even in highly congested and dynamic environments. The b_PE_Disambiguity field could be used to signal the observed channel conditions to other non-legacy nodes, or even indicate a recommended clear channel assessment (CCA) threshold for future transmissions.

graph TD
    A[IoT Non-Legacy Node] --> B{Transceiver};
    A --> C[Local IoT Sensors (Channel Monitoring)];
    C -- Real-time Data --> D[Processor];
    D -- Adapts L-SIG Parameters --> E[L-SIG Generator];
    E --> B;
    B -- TX Non-Legacy Frame --> F[Legacy IoT Sensor];
    F -- Decodes L-LENGTH --> G[Defers TX];

Derivative 4.3: Blockchain-Verified Coexistence Signaling

Enabling Description:
To enhance trust and prevent malicious interference in shared spectrum, the wireless communication terminal integrates blockchain technology for verifying coexistence signaling. The 'remaining value' obtained from dividing L_LENGTH by the legacy data size, or the b_PE_Disambiguity field, would include a cryptographic hash or a signature of critical non-legacy frame parameters (e.g., T_HE_PREAMBLE, T_SYM, and a unique frame identifier). Before transmitting, the processor would generate this hash and embed it. Upon reception, a non-legacy terminal's processor would re-calculate the expected hash from the received non-legacy frame parameters and compare it with the embedded hash. This comparison, validated against a distributed ledger (blockchain) accessible to all network participants, ensures the integrity and authenticity of the coexistence signaling, preventing rogue devices from misrepresenting frame durations or attempting to hijack channel access.

sequenceDiagram
    participant NT as Non-Legacy Terminal
    participant P as Processor
    participant BC as Blockchain Network
    participant LE as L-SIG Encoder
    participant T as Transceiver
    participant LR as Legacy Receiver
    participant NR as Non-Legacy Receiver
    participant VD as Verification Daemon

    NT->>P: Prepare Non-Legacy Frame
    P->>P: Calculate Frame Parameters (T_HE_PREAMBLE, T_SYM)
    P->>P: Generate Cryptographic Hash of Parameters
    P->>LE: Encode L-LENGTH, m, b_PE_Disambiguity (incl. Hash)
    LE->>T: Transmit Non-Legacy Frame
    T->>LR: L-SIG (Legacy Path)
    LR->>LR: Decode L-LENGTH -> Defer
    T->>NR: HE-SIG/Data (Non-Legacy Path)
    NR->>P: Receive HE-SIG/Data
    P->>P: Extract L-LENGTH, m, b_PE_Disambiguity (and Hash)
    P->>P: Re-calculate Hash from HE-SIG/Data
    P->>VD: Verify Hashes (Local vs. Re-calculated)
    VD->>BC: Query Blockchain for Hash Verification
    BC-->>VD: Verification Result
    VD-->>P: Integrity Confirmed / Denied
    P->>P: Determine N_SYM (if confirmed)

---

5. The "Inverse" or Failure Mode

Derivative 5.1: Graceful Degradation to Legacy-Only Mode

Enabling Description:
The wireless communication terminal is designed to automatically detect severe interference or link degradation conditions that prevent reliable non-legacy frame decoding. Upon detecting a predefined error rate in the HE-SIG or repeated failures in N_SYM calculation (e.g., CRC errors on the HE-SIG, or b_PE_Disambiguity field corruption), the processor initiates a graceful degradation mode. In this mode, the non-legacy terminal ceases to transmit HE-SIG and non-legacy data, instead transmitting only legacy-compatible physical layer frames. If it must send data, it encodes the entire payload within a standard legacy data frame, or uses a series of legacy-compatible short frames. When receiving, it switches to a legacy-only decoding path, ignoring the HE-SIG portion of incoming frames and only acting on the L_LENGTH from the L-SIG to defer access, effectively operating as a purely legacy device until channel conditions improve.

stateDiagram
    state "Normal Non-Legacy Operation" as NORMAL
    state "Degradation Detected" as DEGRADE
    state "Legacy-Only Transmission" as LEGACY_TX
    state "Legacy-Only Reception" as LEGACY_RX
    state "Channel Recovery Detected" as RECOVERY

    NORMAL --> DEGRADE : High Error Rate / N_SYM Calc Failure
    DEGRADE --> LEGACY_TX : Initiate Graceful Degradation
    DEGRADE --> LEGACY_RX : Switch RX Mode
    LEGACY_TX --> RECOVERY : Channel Status Check
    LEGACY_RX --> RECOVERY : Channel Status Check
    RECOVERY --> NORMAL : Channel Conditions Improve

Derivative 5.2: Emergency Low-Power Broadcast (Sentry Mode)

Enabling Description:
For battery-constrained non-legacy wireless communication terminals (e.g., remote environmental sensors, emergency beacons), an "emergency low-power broadcast" or "sentry mode" is implemented. In this mode, the terminal only transmits the absolute minimum necessary information to assert channel presence for a predetermined duration. It transmits a non-legacy physical layer frame where the L_SIG contains the maximum permissible L_LENGTH value for a minimal broadcast, and the HE_SIG is either entirely omitted or reduced to a single symbol with a highly robust modulation (e.g., BPSK) encoding only a critical "emergency signal" bit. The m value and b_PE_Disambiguity would be set to predefined constants to signal this specific low-power mode, indicating that the N_SYM calculation should resolve to zero data symbols, or a single symbolic emergency message. This allows the terminal to consume minimal power while still informing both legacy and non-legacy devices of its urgent channel occupation.

graph TD
    A[Emergency Non-Legacy Terminal] --> B{Low-Power TX Module};
    B -- Transmits Minimal L-SIG --> C[Legacy/Non-Legacy Receiver];
    C -- Decodes Max L-LENGTH --> D[Defers Access (Long Duration)];
    B -- Optional HE-SIG (Emergency Bit) --> E[Non-Legacy Receiver];
    E -- Extracts L-LENGTH, m, b_PE_Disambiguity --> F{Determine N_SYM (Zero/One)};
    F --> G[Recognize Emergency Mode];

Derivative 5.3: Limited-Functionality Debug Mode

Enabling Description:
A non-legacy wireless communication terminal includes a limited-functionality debug mode for diagnostic purposes or initial deployment. In this mode, the processor intentionally simplifies the non-legacy physical layer frame structure. For example, it might always set the b_PE_Disambiguity field to a specific value that forces the N_SYM equation to resolve to a fixed, minimal number of symbols, regardless of the actual data length, implying a debug-specific frame structure. The 'remaining value' in the L_LENGTH calculation would then be used to encode simple debug flags or status indicators (e.g., error codes, device ID). This allows basic communication and debugging information exchange with other non-legacy terminals without requiring full non-legacy decoding capabilities, especially useful during firmware updates or system recovery.

graph TD
    A[Non-Legacy Terminal] --> B{Processor (Debug Mode)};
    B -- Sets Fixed b_PE_Disambiguity --> C[L-SIG/HE-SIG Generator];
    C -- Encodes Debug Flags in Remaining Value --> C;
    C --> D[Transceiver];
    D -- Transmits Debug Frame --> E[Non-Legacy Receiver (Debug Tool)];
    E -- Extracts L-LENGTH, m, b_PE_Disambiguity --> F{Determines N_SYM (Fixed Debug Value)};
    F --> G[Decodes Debug Data/Flags];

---

Combination Prior Art Scenarios

Here are at least three scenarios where US Patent 10,313,077, or its core principles, can be combined with existing open-source standards to demonstrate obviousness or lack of novelty for future inventions.

Combination Prior Art Scenario 1: IEEE 802.11ax and OpenWRT (Open-source Router Firmware)

• Description: The IEEE 802.11ax (Wi-Fi 6) standard already defines mechanisms for efficient coexistence with legacy 802.11 devices, including the structure of its physical layer frames (e.g., HE-SIG fields) and how legacy devices interpret the L-SIG. US Patent 10,313,077's method of deriving non-legacy frame parameters (N_SYM) from the L_LENGTH and a 'remaining value' within the legacy-decodable portion aligns with the objectives of 802.11ax.
• Combination: Integrating the specific N_SYM equation and the use of the b_PE_Disambiguity field (as defined in US10313077) into an open-source 802.11ax driver implementation within OpenWRT. A person skilled in the art, when implementing 802.11ax features on a standard OpenWRT-enabled router (which uses standard hardware like Qualcomm Atheros chipsets), would find it obvious to apply known techniques for conveying additional information in legacy-compatible fields to optimize channel access and frame decoding, especially given the explicit need for backward compatibility in Wi-Fi standards. The mathematical derivation provided in the patent would be a straightforward implementation detail for such an advanced driver.
• Significance: This combination shows that the explicit method for calculating N_SYM and leveraging 'remaining value' for additional signaling could be seen as an obvious optimization within the established 802.11ax framework, especially when considering the need for efficient use of existing L-SIG fields to convey non-legacy information.

Combination Prior Art Scenario 2: LoRaWAN (LPWAN Standard) and Zephyr RTOS (Open-source IoT OS)

• Description: LoRaWAN is an open-source specification for LPWAN communication, primarily operating in unlicensed sub-GHz spectrum. It uses chirp spread spectrum (CSS) modulation. While not directly 802.11, LoRaWAN faces similar coexistence challenges in unlicensed bands with other technologies. The core concept of a preamble containing length information (equivalent to L-SIG) and a subsequent data payload is fundamental to LoRaWAN. Zephyr RTOS is a widely adopted open-source real-time operating system for IoT devices.
• Combination: Applying the principles of US 10,313,077 to a LoRaWAN-enabled device running Zephyr RTOS. A LoRaWAN preamble (which can be detected by simpler LoRa devices) could be used to convey a basic 'length information' for the overall LoRa frame. The "remaining value" derived from this length, or specific bits within a LoRaWAN-defined PHY header, could be used to encode advanced LoRaWAN parameters (e.g., dynamic spreading factor changes, specific coding rates, multi-channel allocation) that are not immediately decodable by simpler LoRa devices but are needed by newer, more capable LoRaWAN terminals. The N_SYM calculation would then be adapted to determine the number of LoRa symbols based on varying spreading factors and coding rates within the non-legacy part of the frame. Given the strong emphasis on power efficiency and long range in LoRaWAN, and the need for efficient spectrum usage, such a method for embedding additional data in the existing preamble structure would be an obvious design choice for a skilled LoRaWAN developer.
• Significance: This extends the patent's core concept beyond 802.11 to other wireless standards facing coexistence issues, particularly in LPWAN, demonstrating the generic applicability and thus potential obviousness of deriving non-legacy parameters from legacy-compatible length information.

Combination Prior Art Scenario 3: Bluetooth Low Energy (BLE) 5.0 and ESP-IDF (Espressif IoT Development Framework)

• Description: Bluetooth Low Energy (BLE) 5.0 introduced extended advertising and other features to improve throughput and range. BLE advertising packets have a well-defined structure, including a preamble and access address (akin to L-STF/L-LTF) and a PDU (Protocol Data Unit) that includes length information. Coexistence between older BLE devices (e.g., BLE 4.x) and newer BLE 5.x devices is a known challenge. The ESP-IDF is an open-source development framework for Espressif's popular Wi-Fi and Bluetooth-enabled microcontrollers, widely used in IoT.
• Combination: Implementing a coexistence scheme on an ESP32 microcontroller using ESP-IDF, leveraging the principles of US 10,313,077 for BLE. A BLE 5.0 device (non-legacy) transmits an extended advertising packet. The initial part of this packet (e.g., the PDU header containing the Length field) is structured to be decodable by older BLE 4.x devices (legacy). This Length field serves as the L_LENGTH. The 'remaining value' obtained from this Length (by dividing by a hypothetical 'data size transmittable by a symbol of a legacy BLE advertising channel') could then be used to embed additional BLE 5.0-specific advertising parameters (e.g., secondary advertising channel index, sync info for periodic advertising) that are not directly interpreted by BLE 4.x devices. The N_SYM calculation, adapted for BLE's GFSK modulation and symbol durations, would then determine the actual number of BLE 5.0 data symbols in the extended advertising payload. This would be an obvious way for a developer to convey more information efficiently within existing BLE frame structures, given the continuous evolution of the standard and the need for backward compatibility.
• Significance: This demonstrates how the patent's methodology for deriving non-legacy details from legacy-compatible length fields can be readily applied to other short-range wireless communication standards like BLE, highlighting its general applicability and therefore the potential for obviousness to a person skilled in the art in similar domains.