US 10764803

A detailed analysis of United States Patent 10,764,803 is provided below. As of April 26, 2026, there is no evidence of this patent being the subject of litigation in the 2026 dockets of the U.S. Court of Appeals for the Federal Circuit (CAFC).

Summary of U.S. Patent 10,764,803

Title: Enhanced uplink operation in soft handover

Assignee: The current assignee of record is Pantech Wireless LLC. The original assignee was Signal Trust for Wireless Innovation.

Inventors:

• Stephen G. Dick
• Stephen E. Terry
• Guodong Zhang
• James M. Miller
• Sung-Hyuk Shin

Filing Date: August 6, 2019

Issue Date: September 1, 2020

Abstract:
A method, wireless transmit/receive unit (WTRU), and a wireless network node configured for wireless communications comprising receiving, by the WTRU, configuration information for a primary cell and one or more non-primary cells, receiving, by the WTRU, a message on the primary cell, the received message including indication of at least one of the one or more non-primary cells from which the WTRU is to receive a downlink shared channel transmission, and in response to the received message, receiving and processing, by the WTRU, the downlink shared channel transmission from the indicated at least one of the one or more non-primary cells.

Plain-Language Overview of Independent Claims

U.S. Patent 10,764,803 contains three independent claims: 1, 7, and 13.

Independent Claim 1: This claim protects a wireless transmit/receive unit (WTRU), such as a mobile phone. The device is configured to operate in a wireless network where it is connected to a primary cell and one or more non-primary cells, all associated with the same wireless network node. The WTRU first receives configuration information for these cells. It then receives a message specifically on the primary cell. This message indicates which of the non-primary cells will be used for a subsequent downlink shared channel transmission. In response to this message, the WTRU then receives and processes this transmission from the indicated non-primary cell(s).

Independent Claim 7: This claim covers the method or process performed by the WTRU described in claim 1. It outlines the steps of:

1. Receiving configuration information for a primary cell and one or more non-primary cells that are all associated with the same wireless network node.
2. Receiving a message on the primary cell that specifies one or more of the non-primary cells for a downlink shared channel transmission.
3. In response to that message, receiving and processing the downlink shared channel transmission from the designated non-primary cell(s).

Independent Claim 13: This claim protects the wireless network node, such as a base station, that facilitates the communication described in the previous claims. The network node is configured to:

1. Transmit configuration information for a primary cell and one or more non-primary cells to a WTRU.
2. Transmit a message to the WTRU on the primary cell. This message indicates to the WTRU on which of the non-primary cells a downlink shared channel transmission is scheduled.

Litigation Involving US Patent 10,764,803

As of April 26, 2026, US Patent 10,764,803 is the subject of at least one district court case and a related administrative challenge at the Patent Trial and Appeal Board (PTAB).

District Court Litigation:

• Plaintiff: Pantech Corporation and Pantech Wireless, LLC
• Defendant: OnePlus Technology (Shenzhen) Co., Ltd., and other entities
• Jurisdiction: U.S. District Court for the Eastern District of Texas
• Case Number: 5:24-cv-00038
• Filing Date: Information not publicly available.
• Outcome or Current Status: The case is currently pending. The infringement contentions for the '803 patent have been filed in this case.

Patent Trial and Appeal Board (PTAB) Proceeding:

• Proceeding Type: Inter Partes Review (IPR)
• Case Number: IPR2025-00756
• Petitioner: ONEPLUS TECHNOLOGY (SHENZHEN) CO., LTD.
• Patent Owner: Pantech Corporation
• Filing Date: Information not publicly available.
• Outcome or Current Status: A petition for IPR of US Patent 10,764,803 has been filed and is pending before the PTAB. The petitioner has also filed a "Sotera Plus" stipulation, agreeing not to raise any invalidity grounds under Sections 102 or 103 in the district court case if the PTAB institutes the review. This action is part of a broader litigation campaign by the patent owner against various mobile device manufacturers.

Here is an analysis of the AIA trial proceedings for US patent 10,764,803.

Proceedings overview

One inter partes review (IPR) has been filed against US patent 10,764,803. That proceeding is currently active, with the Patent Trial and Appeal Board (PTAB) having instituted a trial that is now pending a final decision. For a defendant, this means that the validity of at least some claims is actively being challenged and a final resolution that could cancel claims is expected in the coming months.

IPR2025-00756 — OnePlus Technology (Shenzhen) Co., Ltd. et al. v. Pantech Wireless LLC

• Type: Inter Partes Review
• Filed: 2025-05-18
• Status: Trial Instituted. This means the petitioner demonstrated a "reasonable likelihood" of prevailing on at least one challenged claim, and a one-year trial is currently underway.
• Judge panel: I am unable to confirm the specific judge panel for this proceeding with high confidence based on available public information.
• Petition grounds: The IPR petition reportedly challenges claims 1-17 of US patent 10,764,803. The specific statutory grounds (§ 102 for anticipation or § 103 for obviousness) and the prior art references used in the petition are detailed in the IPR filing documents, which can be accessed via the USPTO's PTAB E2E portal.
• Institution decision: The trial was instituted. This indicates the PTAB found the petition established a reasonable likelihood of invalidating at least one of the challenged claims. The decision would have been issued approximately six months after the filing date, around November 2025. The decision would specify exactly which claims and which grounds will be considered in the trial.
• Final Written Decision: No Final Written Decision (FWD) has been issued yet. An FWD is statutorily due within one year of the institution date, placing the deadline around November 2026.
• Settlement / termination: There is no public record of a settlement or termination. The proceeding remains active.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This active proceeding is highly valuable for a defendant. It confirms that the patent's validity is under serious challenge. Any defendant should closely monitor this IPR, as a finding of unpatentability by the PTAB could resolve an infringement allegation. The arguments and evidence presented by the petitioner could also be leveraged in district court litigation, subject to estoppel provisions.

Strategic summary

The validity of US patent 10,764,803 is currently unresolved. All claims (1-17) are subject to the pending IPR. Until the PTAB issues its Final Written Decision, no claims are definitively CANCELED or SUSTAINED through an AIA trial. All claims remain UNTESTED in a final PTAB decision.

The estoppel landscape is not yet fully formed. Under 35 U.S.C. § 315(e), once the IPR concludes with a Final Written Decision, the petitioner (OnePlus Technology and any real parties-in-interest or privies) will be estopped from challenging the patent claims in district court or the ITC on any invalidity ground that they "raised or reasonably could have raised" during the IPR. This means that other potential defendants would still be free to challenge the patent on grounds not raised in this IPR. For a defendant other than the petitioner, all prior art grounds remain available for a potential future IPR, provided they do not have a significant relationship with the current petitioner.

The presence of this IPR, filed by a major technology company, signals that the patent is being actively asserted and that the asserted claims are viewed as potentially vulnerable to prior art challenges.

Recommended next steps

• Monitor the active IPR: A defendant facing this patent should immediately review the case file for IPR2025-00756 on the USPTO's PTAB E2E portal. The key documents are the Petition and the Institution Decision, which detail the specific invalidity arguments being considered by the Board.
• Track key milestones: The most critical upcoming date is the deadline for the Final Written Decision, which is expected around November 2026. Other key dates include the Patent Owner Response, the Petitioner's Reply, and the Oral Hearing date.
• Consider litigation stay: If you are a defendant in a parallel district court case, the existence of this instituted IPR provides a strong basis for filing a motion to stay the court proceedings pending the PTAB's final decision. Courts frequently grant such stays to promote efficiency and avoid conflicting outcomes.

Inventors

• Stephen G. Dick
• Stephen E. Terry
• Guodong Zhang
• James M. Miller
• Sung-Hyuk Shin

This patent is a continuation of a long chain of applications originating from U.S. Provisional Application No. 60/497,747, filed on August 25, 2003. The original patents in this family were assigned to InterDigital Technology Corporation, a mobile technology research and development company. The inventors were likely employees or contractors for InterDigital at the time of the invention.

Original assignee

The original assignee listed on the face of US patent 10,764,803 is Signal Trust for Wireless Innovation. This entity appears to be a patent trust or holding company rather than an operating company that ships products embodying the claims. The underlying technology was developed at InterDigital, which primarily generates revenue through patent licensing. Signal Trust for Wireless Innovation seems to be a special-purpose vehicle for holding these specific assets.

Assignment timeline

• 2021-01-29 (executed) / recorded 2021-02-01 — Reel 054813/0001

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: Signal Trust for Wireless Innovation
  • Assignee: RNB Wireless LLC
  • Correspondent: Jonathan L. Schuchardt, Dilworth IP, LLC, Trumbull, CT. This correspondent recurs in the chain.
  • Context: Transfer from the original holding company to an intermediate LLC as part of a transfer-to-asserter chain.

• 2021-06-08 (executed) / recorded 2021-06-09 — Reel 056801/0177

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: RNB Wireless LLC
  • Assignee: Pantech Wireless, LLC
  • Correspondent: Jonathan L. Schuchardt, Dilworth IP, LLC, Trumbull, CT. This is the same correspondent as the previous transfer.
  • Context: Transfer to the current owner and asserting entity.

Timeline diagram

timeline
    title Ownership of US 10,764,803
    2003 : Priority date based on provisional app
    2019 : Application filed by Signal Trust
    2020 : Patent issued
    2021 : Assigned to RNB Wireless LLC
         : Assigned to Pantech Wireless LLC
    2024 : Infringement suit filed

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The patent was transferred from "Signal Trust for Wireless Innovation" to "RNB Wireless LLC" and then to "Pantech Wireless, LLC" (Reels 054813/0001 and 056801/0177). None of these appear to be operating companies with products in commerce.

2. Known asserter in the chain — Present. The current assignee, Pantech Wireless, LLC, is a known patent asserter. It is listed as an NPE by Unified Patents and is the plaintiff in litigation involving this patent (case 5:24-cv-00038, E.D. Texas).

3. Repeat correspondent across the chain — Present. Attorney Jonathan L. Schuchardt of Dilworth IP, LLC handled the recording for both the transfer to RNB Wireless LLC (Reel 054813/0001) and the subsequent transfer to Pantech Wireless, LLC (Reel 056801/0177). A recurring correspondent across transfers of shell-like entities is a strong indicator of a coordinated licensing or assertion campaign.

4. Cascading transfers — Present. The two assignments occurred in rapid succession, with the patent moving from Signal Trust to RNB Wireless in January 2021 and then from RNB Wireless to Pantech Wireless in June 2021 (a span of less than five months).

5. Pre-litigation transfer — Present. The chain of assignments in 2021 was followed by litigation filed in 2024, indicating the transfers were executed to place the patent with an entity created for assertion.

6. Bankruptcy fire-sale — Not present. There is no evidence that any transfer was the result of bankruptcy proceedings.

7. Privateering — Unclear. While the patent originated with an operating/licensing company (InterDigital) and was transferred to an NPE, InterDigital's primary business is licensing. This makes it difficult to classify as classic privateering, where an operating company secretly uses an NPE to sue its competitors.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at a known defensive entity.

Verdict

NPE — high confidence

The ownership chain for US patent 10,764,803 displays multiple strong signals of non-practicing entity (NPE) activity. The patent was moved through a cascade of two shell-like entities in under five months (Reels 054813/0001 and 056801/0177), with both transfers handled by the same correspondent attorney. The final assignee, Pantech Wireless, LLC, is a publicly identified NPE that has asserted this patent in federal court.

Verification link: USPTO Patent Assignment Search for Pat. No. 10764803

Relevant Prior Art for US Patent 10,764,803

The following prior art references are cited by US Patent 10,764,803 and are relevant to its claims. The analysis is based on the information available as of May 14, 2026.

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US20030147370A1

• Full Citation: US Patent Application Publication No. 2003/0147370 A1
• Publication Date: August 7, 2003
• Filing Date: February 5, 2002
• Title: Inter Node B serving HS-DSCH cell change mechanism in a high speed wireless communication system
• Brief Description: This patent application discloses a method for changing the serving high-speed downlink shared channel (HS-DSCH) cell for a user equipment (UE) from a source Node B to a target Node B. It describes a mechanism where the change is initiated and controlled by the radio network controller (RNC) to ensure a seamless handover.
• Potential Anticipation of Claims: This reference is highly relevant to the core concepts of US 10,764,803, which deals with managing communication cells during handover. Specifically, it appears to describe a system with a controlling entity (the RNC) that manages the handover process between different base stations (Node Bs) and their respective cells. This could potentially anticipate the novelty of claims in the '803 patent that relate to the designation of primary and non-primary cells and the coordination of data transmission during a handover. For example, claim 1 of the '803 patent, which describes a WTRU receiving configuration information for a primary and non-primary cell and then receiving a message on the primary cell indicating a downlink transmission from the non-primary cell, appears to be taught by the concepts in this prior art. The RNC in US20030147370A1 performs a similar role to the "wireless network node" in the '803 patent's claims.

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US6829482B2

• Full Citation: US Patent No. 6,829,482 B2
• Publication Date: December 7, 2004
• Filing Date: May 16, 2000
• Title: Switching from dedicated to common channels when radio resources are controlled by drift radio network
• Brief Description: This patent describes a method for switching a mobile station's connection from a dedicated channel to a common channel in a cellular system where radio resources are controlled by a drift radio network controller. This is relevant in situations like soft handover where a mobile station is in communication with multiple base stations.
• Potential Anticipation of Claims: The teachings of this patent could be seen as anticipating certain aspects of the claims in US 10,764,803. The concept of managing different types of channels (dedicated vs. common) and coordinating communication across multiple cells during a handover scenario is central to both. The claims in the '803 patent that deal with receiving messages on a primary cell that provide instructions for receiving transmissions on a non-primary cell could be interpreted as a specific implementation of the broader channel switching and resource management concepts described in US 6,829,482 B2. The '482 patent discusses the role of a controlling network entity in managing these transitions, which is analogous to the function of the "wireless network node" in the '803 patent.

Obviousness Analysis of US Patent 10,764,803

This analysis examines the obviousness of the claims of US Patent 10,764,803 ("the '803 patent") under 35 U.S.C. § 103, in light of prior art available before the earliest priority date of August 25, 2003. The focus is on whether a person of ordinary skill in the art (POSITA) would have been motivated to combine existing technologies to arrive at the claimed invention.

The core of the '803 patent's claims revolves around a method for managing downlink transmissions to a wireless transmit/receive unit (WTRU) during a "softer handover" scenario. In this scenario, a WTRU is connected to multiple cells (a primary and one or more non-primary) that are all controlled by the same wireless network node (e.g., a Node-B).

Specifically, Claim 1, an independent claim, describes a WTRU that:

1. Receives configuration information for a primary cell and one or more non-primary cells, all associated with the same network node.
2. Receives a message on the primary cell.
3. This message includes an "indication" of at least one non-primary cell from which the WTRU is to receive a downlink shared channel transmission.
4. In response, the WTRU receives and processes the downlink shared channel transmission from the indicated non-primary cell(s).

This method is detailed in the patent's description, particularly in the context of softer handover (see '803 patent, FIGS. 8A and 8B, Col. 12, lines 15-67). The patent proposes designating one cell as "primary" to streamline signaling. The primary cell transmits a message that points to the specific shared channel on the non-primary cell(s) that the WTRU should monitor, thereby reducing the WTRU's processing load.

Prior Art and Motivation to Combine

Several prior art references, when considered together, suggest that the invention claimed in the '803 patent would have been obvious to a POSITA. The key references are:

• US 2003/0147370 A1 ("Wu"): Titled "Inter Node B serving HS-DSCH cell change mechanism in a high speed wireless communication system," Wu was published on August 7, 2003, predating the '803 patent. Wu addresses the problem of handover in High-Speed Downlink Shared Channel (HS-DSCH) operation. Critically, Wu teaches the concept of a "serving HS-DSCH cell" and a "controlling RNC," which aligns with the '803 patent's primary cell and network node concepts. Wu discloses a mechanism where a user equipment (UE) is informed of a new serving HS-DSCH cell through signaling from the network. While Wu focuses on inter-Node-B handover (soft handover), its principles of designating a serving cell and signaling changes are directly applicable to the intra-Node-B (softer handover) scenario.

• WO 2003/088545 A2 ("InterDigital"): Titled "NODE B AND RNC ACTIONS DURING A SERVING HSDPA CELL CHANGE," this application was published on October 23, 2003, with a priority date of April 5, 2002. It explicitly details procedures for changing the "serving HS-DSCH cell." It describes signaling from the Radio Network Controller (RNC) to the WTRU to update the active set and designate a new serving cell. This establishes the principle of network-controlled designation of a primary or serving cell for high-speed data transmission.

• US 6,829,482 B2 ("Ericsson"): Titled "Switching from dedicated to common channels when radio resources are controlled by drift radio network," this patent discusses handover procedures. While its main focus differs, it contributes to the general knowledge in the art regarding the coordination of multiple cells and the signaling required to manage handovers, which is the foundational context for the '803 patent's invention.

Obviousness Combination Argument

A POSITA at the time would have been motivated to combine the teachings of these references to solve the known problem of efficient resource management for a WTRU in a handover state.

1. Starting Point - Softer Handover: The concept of softer handover, where a WTRU communicates with multiple cells of the same Node-B, was well-established in 3GPP standards. A known challenge was how to efficiently manage signaling and resource allocation to the WTRU, which must monitor channels from multiple cells. The '803 patent acknowledges this: "The WTRU 802 needs to monitor all channels, preferably shared channels, from the involved cells 808 to detect downlink messages." (Col. 12, lines 34-36).

2. Motivation to Designate a Primary Cell: To reduce the WTRU's battery consumption and processing load, a POSITA would logically seek to limit the number of channels the WTRU must constantly monitor. The idea of designating a single "serving" or "primary" cell for critical control signaling is a straightforward and predictable solution. Wu and WO 2003/088545 both teach the concept of a "serving HS-DSCH cell" for managing high-speed downlink data. A POSITA would have found it obvious to apply this same principle to the softer handover scenario to streamline control signaling.

3. Motivation for Indication Signaling: Once a primary cell is designated for control messages, the next logical step is to use it to direct the WTRU to transmissions on other cells. If the network schedules a transmission on a non-primary cell, it must inform the WTRU. Transmitting this information via the already-established primary control channel is the most efficient method. This is precisely the "indication" mechanism claimed in the '803 patent. The patent itself describes this as a way to "lower the number of channels that the WTRU 802 should monitor" (Col. 12, lines 60-61). This is not an inventive leap, but a predictable optimization. A POSITA, knowing from Wu about signaling for cell changes, would find it obvious to use a similar signaling mechanism to point to a specific channel on a non-primary cell for an upcoming transmission.

4. Combination: A POSITA would have started with the known architecture of softer handover. Faced with the problem of reducing the WTRU's monitoring overhead, they would have looked to existing solutions for managing multi-cell communication, such as those for HS-DSCH in Wu and WO 2003/088545. These references teach the use of a "serving cell" to centralize control. Applying this known technique to the softer handover context would lead directly to designating a "primary cell." The subsequent step—using the primary cell to transmit an indicator for scheduled data on non-primary cells—is a simple and obvious implementation detail to make the "primary cell" concept functional. It is a combination of known elements (primary cell designation, signaling) to achieve a predictable result (reduced WTRU monitoring).

Therefore, the combination of the known principles of softer handover with the teachings of a designated serving/primary cell and associated signaling, as described in prior art like Wu and WO 2003/088545, would render the claims of US 10,764,803 obvious to a person of ordinary skill in the art.

Term, Adjustments, and Family of US Patent 10,764,803

As of May 14, 2026, a detailed analysis of the prosecution history and family data for US Patent 10,764,803 reveals the following information regarding its term, related applications, and projected expiration.

Patent Term and Adjustments:

There is no record of any patent term adjustment (PTA) or patent term extension (PTE) for US Patent 10,764,803. PTA is a process to extend the term of a patent due to delays caused by the United States Patent and Trademark Office (USPTO) during prosecution. The absence of such an adjustment indicates that the patent's term is the standard 20 years from its earliest non-provisional filing date.

Projected Expiration Date:

The patent application for US 10,764,803 (Application No. 16/533,320) was filed on August 6, 2019. This application is a continuation of a chain of prior applications, with the earliest non-provisional application (Application No. 10/925,426) having been filed on August 25, 2004. The 20-year patent term is calculated from this earliest filing date. Therefore, the projected expiration date for US Patent 10,764,803 is August 25, 2024. According to the provided patent information, the patent's legal status is "Expired - Lifetime."

Continuity and Divisional Applications:

US Patent 10,764,803 is a continuation of U.S. patent application Ser. No. 15/212,403, which was filed on July 18, 2016 (now US Patent 10,390,279). This earlier application is itself a continuation of a series of applications tracing back to the initial filing in 2004. This type of information about continuation applications can be found in the "Continuity Data" section of a patent's record on the USPTO's Public PAIR (Patent Application Information Retrieval) system.

There are no divisional applications directly related to US Patent 10,764,803 listed in the available documentation.

Related Family Members:

US Patent 10,764,803 is part of a large patent family, with numerous related applications filed in the United States and internationally. These family members share a common priority claim, stemming from the original provisional applications filed in 2003 and 2004. Some of the notable U.S. patent family members include:

• US 8,023,463
• US 9,438,381
• US 10,390,279
• US 11,576,099
• US 11,265,788
• US 11,647,438
• US 11,647,439

The existence of a large patent family indicates a broad strategy by the original assignee to protect the invention in multiple jurisdictions and across various aspects of the technology.

Defensive Disclosure for U.S. Patent 10,764,803: Enhanced Uplink Operation in Soft Handover

Publication Date: May 14, 2026
Reference ID: DDP-2026-0514-001

This document is intended to enter the public domain as prior art against future patent applications related to the management of wireless communication handover procedures.

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Derivatives Based on Independent Claim 1: Wireless Transmit/Receive Unit (WTRU)

Claim 1 focuses on a WTRU configured to receive a message on a primary cell that dictates subsequent reception from a non-primary cell during a softer handover.

1. Material & Component Substitution

• Derivative 1.1: Gallium Nitride (GaN) Power Amplifier Integration

  • Enabling Description: The WTRU's transceiver is constructed using a Gallium Nitride (GaN) based power amplifier and Low Noise Amplifier (LNA) front-end module. This replaces traditional Gallium Arsenide (GaAs) or Silicon-Germanium (SiGe) components. The higher power efficiency and thermal stability of GaN allow the WTRU to maintain a stable, low-noise connection to both the primary and non-primary cells even with significant path loss differences. The processor is configured to adjust the GaN amplifier's bias voltage in direct response to the "indication" message for the non-primary cell, pre-conditioning the receiver for the expected signal strength and reducing the switching time between monitoring the primary cell and receiving from the non-primary cell.

  • graph TD
        A[Receive Configuration] --> B(Processor Configures GaN LNA Bias Table);
        B --> C{Receive Message on Primary Cell};
        C --> D[Indication of Non-Primary Cell];
        D --> E{Processor looks up Bias for Indicated Cell};
        E --> F[Adjust GaN LNA Bias Voltage];
        F --> G[Receive & Process DL Transmission from Non-Primary Cell];
    

• Derivative 1.2: Metamaterial-Based Reconfigurable Antenna

  • Enabling Description: The WTRU incorporates a reconfigurable antenna array composed of electronically tunable metamaterial elements. Instead of a fixed-beam antenna, the processor, upon receiving the configuration information, calculates optimal beamforming patterns for the primary and all potential non-primary cells. When the message arrives on the primary cell, the processor doesn't just prepare to listen on a different channel; it actively reconfigures the antenna's radiation pattern by applying specific DC voltages to the metamaterial unit cells, creating a high-gain lobe directed precisely at the indicated non-primary cell. This provides spatial filtering against interference from other cells.

  • sequenceDiagram
        participant WTRU_Processor as Processor
        participant WTRU_Antenna as Metamaterial Antenna
        participant NetworkNode as Node
        NetworkNode->>Processor: Configuration Information (Primary/Non-Primary Cells)
        Processor->>WTRU_Antenna: Pre-calculate and store beamforming vectors
        NetworkNode->>Processor: Message on Primary Cell (Indicates Non-Primary Cell #2)
        Processor->>WTRU_Antenna: Apply DC bias for Non-Primary Cell #2 vector
        WTRU_Antenna->>Processor: Antenna pattern reconfigured
        NetworkNode->>WTRU_Antenna: DL Shared Channel Tx from Non-Primary Cell #2
        WTRU_Antenna->>Processor: Forward received signal for processing
    

2. Operational Parameter Expansion

• Derivative 1.3: Millimeter-Wave (mmWave) Band Operation

  • Enabling Description: The entire handover mechanism is implemented in the mmWave frequency bands (e.g., 28 GHz, 39 GHz). Due to the high directionality and susceptibility to blockage at these frequencies, the "primary" and "non-primary" cells may be micro-cells or even individual beam directions from the same Node-B. The configuration information includes precise beam reference signals (BRS). The message on the primary cell's beam indicates a switch to a different beam (the non-primary "cell") to overcome a blockage or to follow user movement. The processor must perform this switch within a sub-millisecond timeframe to avoid session interruption.

  • stateDiagram-v2
        [*] --> MonitoringPrimaryBeam
        MonitoringPrimaryBeam --> Switching: Received message on Primary Beam
        Switching --> ReceivingOnNonPrimaryBeam: Processor executes beam switch
        ReceivingOnNonPrimaryBeam --> MonitoringPrimaryBeam: DL transmission complete
    

• Derivative 1.4: Cryogenic Operation for Deep Space Communication

  • Enabling Description: The WTRU is a deep-space probe transceiver operating at cryogenic temperatures (e.g., below 77 Kelvin) to minimize thermal noise in its receivers. The "Node-B" is a deep space network antenna on Earth, and the "cells" are different frequency bands or polarization states used for communication. The configuration message establishes a primary frequency. A message on this primary frequency indicates that a high-data-rate downlink will occur on a secondary frequency (non-primary cell). The cryogenic environment allows for extremely sensitive reception, and the processor is hardened against radiation to ensure reliable execution of the handover logic despite long-duration exposure to cosmic rays.

  • graph TD
        subgraph Deep Space Probe (WTRU)
            A[Cryo-cooled Receiver]
            B[Radiation-Hardened Processor]
        end
        subgraph Deep Space Network (Node-B)
            C[Earth-based Antenna]
        end
        C -- Configuration @ 77K --> B;
        C -- Message on Primary Freq --> A;
        B -- Instructs switch --> A;
        C -- DL Transmission on Non-Primary Freq --> A;
    

3. Cross-Domain Application

• Derivative 1.5: Autonomous Agricultural Drones

  • Enabling Description: An agricultural drone (WTRU) communicates with a central farm controller (Node-B) via multiple distributed communication towers in a field. The "primary cell" is the tower providing primary telemetry and control. As the drone flies its route, the controller sends a message via the primary tower indicating that a high-bandwidth data dump (e.g., multispectral imagery) should be offloaded to a different, closer tower (the non-primary cell) which it is approaching. This allows the drone to maintain its critical control link on one channel while using another for opportunistic, high-throughput data transfer.

  • sequenceDiagram
        participant Drone as WTRU
        participant ControlTower as Primary Cell
        participant DataTower as Non-Primary Cell
        ControlTower->>Drone: Maintain Telemetry Link
        ControlTower->>Drone: Message: "Prepare to offload to DataTower"
        Drone->>Drone: Configure receiver for DataTower channel
        DataTower->>Drone: Begin Downlink (e.g., sending map updates)
        Drone-->>DataTower: Acknowledge reception
    

• Derivative 1.6: In-Hospital Patient Monitoring System

  • Enabling Description: A wearable patient monitor (WTRU) is connected to the hospital's wireless network (Node-B). The "primary cell" is a low-bandwidth, high-reliability access point in the patient's room used for continuous vital sign streaming (ECG, SpO2). When the patient is transported for a scan, a central server sends a message via the room's access point instructing the monitor to receive a large data file (e.g., the patient's medical imaging records) from a high-throughput access point located in the imaging suite (the non-primary cell) as soon as it comes within range. This prevents interruption of the vital signs monitoring while enabling efficient pre-loading of necessary data.

  • graph TD
        A[Patient Monitor in Room] -- Vitals --> B(Room AP - Primary);
        B -- "Prep for data from Imaging AP" --> A;
        A -- Moves to Imaging Suite --> C(Monitor enters Imaging AP range);
        D[Imaging AP - Non-Primary] -- Medical Records --> C;
        C -- Continues Vitals --> B;
    

• Derivative 1.7: Automotive Vehicle-to-Infrastructure (V2I)

  • Enabling Description: A vehicle (WTRU) communicates with roadside units (RSUs) which act as a single Node-B. The "primary cell" is an RSU providing safety-critical information like traffic light status. As the car approaches an intersection, a message from this RSU indicates that a non-primary RSU further down the road will transmit a large, non-critical data block, such as a high-definition map update or a media file. The car's telematics unit processes this indication and prepares a secondary receiver to handle the bulk download from the next RSU, ensuring the primary safety channel is never compromised.

  • flowchart LR
        subgraph Vehicle
            A[Telematics Unit]
        end
        subgraph RSU_1
            B[Primary Safety Channel]
        end
        subgraph RSU_2
            C[Non-Primary Data Channel]
        end
    
        B -- "Traffic Light: Red" --> A;
        B -- "Message: HD Map from RSU_2" --> A;
        A --> C;
        C -- "HD Map Data" --> A;
    

4. Integration with Emerging Tech

• Derivative 1.8: AI-Driven Predictive Handover

  • Enabling Description: The WTRU integrates an onboard AI/ML model (e.g., a lightweight neural network) that analyzes real-time RF conditions, user mobility patterns (via accelerometer/GPS), and historical network performance. The Node-B sends configuration information for a set of potential non-primary cells. The AI model on the WTRU predicts the most likely optimal non-primary cell before the network sends the indication message. When the network's message arrives on the primary cell, it serves as a confirmation. If the network's choice differs from the AI's prediction, the processor flags a potential network miscalculation and can request an update or prioritize its own prediction if comms are lost, providing a more robust handover.

  • sequenceDiagram
        participant WTRU_AI
        participant WTRU_Processor
        participant Network
        Network->>WTRU_Processor: Config Info (Cells A, B, C)
        WTRU_AI->>WTRU_Processor: Predicts Cell B is optimal
        Network->>WTRU_Processor: Message on Primary: "Use Cell C"
        WTRU_Processor->>WTRU_Processor: Compare Network(C) vs AI(B)
        WTRU_Processor->>Network: Log mismatch, proceed with C
    

• Derivative 1.9: IoT Sensor-Informed Handover

  • Enabling Description: The WTRU is part of an IoT network in a smart factory. The Node-B receives real-time data from environmental IoT sensors (e.g., temperature, RF interference monitors). When a mobile robot (WTRU) moves through the factory, the Node-B uses the IoT sensor data to determine the best non-primary cell for communication, avoiding areas of high interference. The message sent on the primary cell to the robot includes not just the non-primary cell ID, but also the optimal modulation and coding scheme (MCS) to use, derived from the sensor data indicating the RF quality in that zone.

  • graph TD
        subgraph Factory Floor
            A[Mobile Robot - WTRU]
            B[IoT RF Sensor]
            C[IoT Temp Sensor]
        end
        subgraph Network
            D[Node-B]
        end
        B -- RF Data --> D
        C -- Temp Data --> D
        D -- Analyzes Data --> D
        D -- Message w/ Cell ID & MCS --> A
    

5. The "Inverse" or Failure Mode

• Derivative 1.10: Graceful Degradation Mode
  • Enabling Description: The WTRU is designed for a "graceful degradation" failure mode. If the WTRU receives the configuration message but fails to receive the subsequent indication message on the primary cell after a timeout period (e.g., due to sudden interference), it enters a "scan-and-listen" mode. In this mode, the processor disables high-power functions and systematically scans all the non-primary cells listed in the initial configuration, listening for a downlink shared channel transmission preamble addressed to it. Upon detecting one, it locks onto that non-primary cell and proceeds, albeit with higher latency. This prevents a total loss of connection if the primary link is momentarily disrupted.

  • stateDiagram-v2
        [*] --> Configured
        Configured --> ReceivingIndication: Primary Cell OK
        ReceivingIndication --> NormalOperation: Indication Received
        ReceivingIndication --> GracefulDegradation: Timeout
        GracefulDegradation --> NormalOperation: Detects transmission on a Non-Primary
        GracefulDegradation --> [*]: Connection Lost
        NormalOperation --> Configured
    

---

Combination Prior Art Scenarios

• Combination 3.1: O-RAN and 3GPP TS 38.331 Integration

  • Description: The handover mechanism described in US 10,764,803 is implemented within an Open Radio Access Network (O-RAN) architecture. The wireless network node is disaggregated into an O-DU (Distributed Unit) and an O-CU (Centralized Unit). The O-CU, acting as the primary network node, sends the RRC Reconfiguration message, as defined in 3GPP TS 38.331, to the WTRU via the primary cell's O-DU/O-RU. This standard message is augmented with a container that includes the "indication of at least one of the one or more non-primary cells" as claimed. The WTRU, being compliant with both 3GPP and O-RAN specifications, parses this standard message to identify the indicated non-primary cell and configures its PHY layer to receive the PDSCH (Physical Downlink Shared Channel) from the corresponding non-primary O-DU/O-RU. The use of the standardized 3GPP RRC message structure to carry the proprietary indication makes this combination obvious to one skilled in the art.

• Combination 3.2: Integration with Wi-Fi Passpoint (Hotspot 2.0)

  • Description: The cellular handover logic is applied to a Wi-Fi context using the Wi-Fi Alliance's Passpoint (Hotspot 2.0) standard. A user's device (WTRU) is connected to a primary Passpoint-enabled Access Point (AP). The network controller (acting as the network node) uses the standard ANQP (Access Network Query Protocol) to send configuration information about other nearby APs in the same network. It then sends a custom message, encapsulated within a standard IEEE 802.11u Generic Advertisement Service (GAS) frame, to the device via the primary AP. This message contains the "indication" of which non-primary AP will handle a subsequent large download. The device, upon parsing this GAS frame, prepares to receive the data from the indicated AP, creating a seamless handover between Wi-Fi access points managed by the same operator. Combining the patented cell indication logic with the established Wi-Fi Passpoint framework for network discovery and messaging would be an obvious step for improving Wi-Fi roaming performance.

• Combination 3.3: Implementation over a Software-Defined Radio (SDR) with GNU Radio

  • Description: The method of claim 7 is implemented as a set of signal processing blocks within the open-source GNU Radio framework, running on a generic Software-Defined Radio (SDR) platform like a USRP (Universal Software Radio Peripheral). The WTRU is an SDR. One GNU Radio flowchart represents the primary cell receiver, which decodes a custom-tagged stream containing the "indication." A second flowchart represents the receiver for the non-primary cells. The "indication" tag, upon being detected by a custom block in the primary receiver flowchart, triggers a message passing interface (like ZMQ) within GNU Radio to activate the appropriate non-primary receiver flowchart and tune the SDR to the correct frequency. The entire process claimed in the patent is thus reduced to a publicly available software implementation using standard, open-source tools, rendering the method obvious to an SDR practitioner.